Make archspec a vendored dependency (#19600)

- Added archspec to the list of vendored dependencies
- Removed every reference to llnl.util.cpu
- Removed tests from Spack code base

50 files changed, 1887 insertions, 1565 deletions

diff --git a/lib/spack/external/__init__.py b/lib/spack/external/__init__.py
index 230ec170b2..ffe3d0d9d7 100644
--- a/lib/spack/external/__init__.py
+++ b/lib/spack/external/__init__.py
@@ -6,6 +6,13 @@
 """This module contains the following external, potentially separately
 licensed, packages that are included in Spack:
 
+archspec
+--------
+
+* Homepage: https://pypi.python.org/pypi/archspec
+* Usage: Labeling, comparison and detection of microarchitectures
+* Version: 0.1.2 (commit 6e1b6502bb0a743d44a5eed7cfbbb84b4b817c43)
+
 argparse
 --------
 
diff --git a/lib/spack/external/archspec/COPYRIGHT b/lib/spack/external/archspec/COPYRIGHT
new file mode 100644
index 0000000000..4164e98de7
--- /dev/null
+++ b/lib/spack/external/archspec/COPYRIGHT
@@ -0,0 +1,22 @@
+Intellectual Property Notice
+------------------------------
+
+Archspec is licensed under the Apache License, Version 2.0 (LICENSE-APACHE
+or http://www.apache.org/licenses/LICENSE-2.0) or the MIT license,
+(LICENSE-MIT or http://opensource.org/licenses/MIT), at your option.
+
+Copyrights and patents in the Archspec project are retained by contributors.
+No copyright assignment is required to contribute to Archspec.
+
+
+SPDX usage
+------------
+
+Individual files contain SPDX tags instead of the full license text.
+This enables machine processing of license information based on the SPDX
+License Identifiers that are available here: https://spdx.org/licenses/
+
+Files that are dual-licensed as Apache-2.0 OR MIT contain the following
+text in the license header:
+
+    SPDX-License-Identifier: (Apache-2.0 OR MIT)
diff --git a/lib/spack/external/archspec/LICENSE-APACHE b/lib/spack/external/archspec/LICENSE-APACHE
new file mode 100644
index 0000000000..d645695673
--- /dev/null
+++ b/lib/spack/external/archspec/LICENSE-APACHE
@@ -0,0 +1,202 @@
+
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diff --git a/lib/spack/external/archspec/LICENSE-MIT b/lib/spack/external/archspec/LICENSE-MIT
new file mode 100644
index 0000000000..03be635ad5
--- /dev/null
+++ b/lib/spack/external/archspec/LICENSE-MIT
@@ -0,0 +1,20 @@
+Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+Archspec Project Developers. See the top-level COPYRIGHT file for details.
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
diff --git a/lib/spack/external/archspec/README.md b/lib/spack/external/archspec/README.md
new file mode 100644
index 0000000000..015eb684b5
--- /dev/null
+++ b/lib/spack/external/archspec/README.md
@@ -0,0 +1,68 @@
+[![](https://github.com/archspec/archspec/workflows/Unit%20tests/badge.svg)](https://github.com/archspec/archspec/actions)
+[![codecov](https://codecov.io/gh/archspec/archspec/branch/master/graph/badge.svg)](https://codecov.io/gh/archspec/archspec)
+[![Documentation Status](https://readthedocs.org/projects/archspec/badge/?version=latest)](https://archspec.readthedocs.io/en/latest/?badge=latest)
+
+
+# Archspec (Python bindings)
+
+Archspec aims at providing a standard set of human-understandable labels for
+various aspects of a system architecture  like CPU, network fabrics, etc. and
+APIs to detect, query and compare them.
+
+This project grew out of [Spack](https://spack.io/) and is currently under
+active development. At present it supports APIs to detect and model
+compatibility relationships among different CPU microarchitectures.
+
+## Getting started with development
+
+The `archspec` Python package needs [poetry](https://python-poetry.org/) to
+be installed from VCS sources. The preferred method to install it is via
+its custom installer outside of any virtual environment:
+```console
+$ curl -sSL https://raw.githubusercontent.com/python-poetry/poetry/master/get-poetry.py | python
+```
+You can refer to [Poetry's documentation](https://python-poetry.org/docs/#installation)
+for further details or for other methods to install this tool. You'll also need `tox`
+to run unit test:
+```console
+$ pip install --user tox
+```
+Finally you'll need to clone the repository:
+```console
+$ git clone --recursive https://github.com/archspec/archspec.git
+```
+
+### Running unit tests
+Once you have your environment ready you can run `archspec` unit tests
+using ``tox`` from the root of the repository:
+```console
+$ tox
+  [ ... ]
+  py27: commands succeeded
+  py35: commands succeeded
+  py36: commands succeeded
+  py37: commands succeeded
+  py38: commands succeeded
+  pylint: commands succeeded
+  flake8: commands succeeded
+  black: commands succeeded
+  congratulations :)
+```
+
+## License
+
+Archspec is distributed under the terms of both the MIT license and the
+Apache License (Version 2.0). Users may choose either license, at their
+option.
+
+All new contributions must be made under both the MIT and Apache-2.0
+licenses.
+
+See [LICENSE-MIT](https://github.com/archspec/archspec/blob/master/LICENSE-MIT),
+[LICENSE-APACHE](https://github.com/archspec/archspec/blob/master/LICENSE-APACHE),
+[COPYRIGHT](https://github.com/archspec/archspec/blob/master/COPYRIGHT), and
+[NOTICE](https://github.com/archspec/archspec/blob/master/NOTICE) for details.
+
+SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+LLNL-CODE-811653
diff --git a/lib/spack/external/archspec/__init__.py b/lib/spack/external/archspec/__init__.py
new file mode 100644
index 0000000000..1349425634
--- /dev/null
+++ b/lib/spack/external/archspec/__init__.py
@@ -0,0 +1,2 @@
+"""Init file to avoid namespace packages"""
+__version__ = "0.1.1"
diff --git a/lib/spack/external/archspec/cli.py b/lib/spack/external/archspec/cli.py
new file mode 100755
index 0000000000..4338b84fed
--- /dev/null
+++ b/lib/spack/external/archspec/cli.py
@@ -0,0 +1,24 @@
+# Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+# Archspec Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+"""
+archspec command line interface
+"""
+
+import click
+
+import archspec
+import archspec.cpu
+
+
+@click.group(name="archspec")
+@click.version_option(version=archspec.__version__)
+def main():
+    """archspec command line interface"""
+
+
+@main.command()
+def cpu():
+    """archspec command line interface for CPU"""
+    click.echo(archspec.cpu.host())
diff --git a/lib/spack/external/archspec/cpu/__init__.py b/lib/spack/external/archspec/cpu/__init__.py
new file mode 100644
index 0000000000..b3ea025732
--- /dev/null
+++ b/lib/spack/external/archspec/cpu/__init__.py
@@ -0,0 +1,20 @@
+# Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+# Archspec Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+"""The "cpu" package permits to query and compare different
+CPU microarchitectures.
+"""
+from .microarchitecture import Microarchitecture, UnsupportedMicroarchitecture
+from .microarchitecture import TARGETS, generic_microarchitecture
+from .microarchitecture import version_components
+from .detect import host
+
+__all__ = [
+    "Microarchitecture",
+    "UnsupportedMicroarchitecture",
+    "TARGETS",
+    "generic_microarchitecture",
+    "host",
+    "version_components",
+]
diff --git a/lib/spack/external/archspec/cpu/alias.py b/lib/spack/external/archspec/cpu/alias.py
new file mode 100644
index 0000000000..b93972fe81
--- /dev/null
+++ b/lib/spack/external/archspec/cpu/alias.py
@@ -0,0 +1,88 @@
+# Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+# Archspec Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+"""Aliases for microarchitecture features."""
+# pylint: disable=useless-object-inheritance
+from .schema import TARGETS_JSON, LazyDictionary
+
+_FEATURE_ALIAS_PREDICATE = {}
+
+
+class FeatureAliasTest(object):
+    """A test that must be passed for a feature alias to succeed.
+
+    Args:
+        rules (dict): dictionary of rules to be met. Each key must be a
+            valid alias predicate
+    """
+
+    # pylint: disable=too-few-public-methods
+    def __init__(self, rules):
+        self.rules = rules
+        self.predicates = []
+        for name, args in rules.items():
+            self.predicates.append(_FEATURE_ALIAS_PREDICATE[name](args))
+
+    def __call__(self, microarchitecture):
+        return all(feature_test(microarchitecture) for feature_test in self.predicates)
+
+
+def _feature_aliases():
+    """Returns the dictionary of all defined feature aliases."""
+    json_data = TARGETS_JSON["feature_aliases"]
+    aliases = {}
+    for alias, rules in json_data.items():
+        aliases[alias] = FeatureAliasTest(rules)
+    return aliases
+
+
+FEATURE_ALIASES = LazyDictionary(_feature_aliases)
+
+
+def alias_predicate(func):
+    """Decorator to register a predicate that can be used to evaluate
+    feature aliases.
+    """
+    name = func.__name__
+
+    # Check we didn't register anything else with the same name
+    if name in _FEATURE_ALIAS_PREDICATE:
+        msg = 'the alias predicate "{0}" already exists'.format(name)
+        raise KeyError(msg)
+
+    _FEATURE_ALIAS_PREDICATE[name] = func
+
+    return func
+
+
+@alias_predicate
+def reason(_):
+    """This predicate returns always True and it's there to allow writing
+    a documentation string in the JSON file to explain why an alias is needed.
+    """
+    return lambda x: True
+
+
+@alias_predicate
+def any_of(list_of_features):
+    """Returns a predicate that is True if any of the feature in the
+    list is in the microarchitecture being tested, False otherwise.
+    """
+
+    def _impl(microarchitecture):
+        return any(x in microarchitecture for x in list_of_features)
+
+    return _impl
+
+
+@alias_predicate
+def families(list_of_families):
+    """Returns a predicate that is True if the architecture family of
+    the microarchitecture being tested is in the list, False otherwise.
+    """
+
+    def _impl(microarchitecture):
+        return str(microarchitecture.family) in list_of_families
+
+    return _impl
diff --git a/lib/spack/llnl/util/cpu/detect.py b/lib/spack/external/archspec/cpu/detect.py
index 66b09f5e9e..e65076c788 100644
--- a/lib/spack/llnl/util/cpu/detect.py
+++ b/lib/spack/external/archspec/cpu/detect.py
@@ -1,7 +1,8 @@
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
-# Spack Project Developers. See the top-level COPYRIGHT file for details.
+# Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+# Archspec Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
+"""Detection of CPU microarchitectures"""
 import collections
 import functools
 import os
@@ -12,16 +13,16 @@ import warnings
 
 import six
 
-from .microarchitecture import generic_microarchitecture, targets
-from .schema import targets_json
+from .microarchitecture import generic_microarchitecture, TARGETS
+from .schema import TARGETS_JSON
 
 #: Mapping from operating systems to chain of commands
 #: to obtain a dictionary of raw info on the current cpu
-info_factory = collections.defaultdict(list)
+INFO_FACTORY = collections.defaultdict(list)
 
 #: Mapping from micro-architecture families (x86_64, ppc64le, etc.) to
 #: functions checking the compatibility of the host with a given target
-compatibility_checks = {}
+COMPATIBILITY_CHECKS = {}
 
 
 def info_dict(operating_system):
@@ -32,8 +33,9 @@ def info_dict(operating_system):
         operating_system (str or tuple): operating system for which the marked
             function is a viable factory of raw info dictionaries.
     """
+
     def decorator(factory):
-        info_factory[operating_system].append(factory)
+        INFO_FACTORY[operating_system].append(factory)
 
         @functools.wraps(factory)
         def _impl():
@@ -41,10 +43,10 @@ def info_dict(operating_system):
 
             # Check that info contains a few mandatory fields
             msg = 'field "{0}" is missing from raw info dictionary'
-            assert 'vendor_id' in info, msg.format('vendor_id')
-            assert 'flags' in info, msg.format('flags')
-            assert 'model' in info, msg.format('model')
-            assert 'model_name' in info, msg.format('model_name')
+            assert "vendor_id" in info, msg.format("vendor_id")
+            assert "flags" in info, msg.format("flags")
+            assert "model" in info, msg.format("model")
+            assert "model_name" in info, msg.format("model_name")
 
             return info
 
@@ -53,15 +55,15 @@ def info_dict(operating_system):
     return decorator
 
 
-@info_dict(operating_system='Linux')
+@info_dict(operating_system="Linux")
 def proc_cpuinfo():
     """Returns a raw info dictionary by parsing the first entry of
     ``/proc/cpuinfo``
     """
     info = {}
-    with open('/proc/cpuinfo') as file:
+    with open("/proc/cpuinfo") as file:
         for line in file:
-            key, separator, value = line.partition(':')
+            key, separator, value = line.partition(":")
 
             # If there's no separator and info was already populated
             # according to what's written here:
@@ -70,44 +72,43 @@ def proc_cpuinfo():
             #
             # we are on a blank line separating two cpus. Exit early as
             # we want to read just the first entry in /proc/cpuinfo
-            if separator != ':' and info:
+            if separator != ":" and info:
                 break
 
             info[key.strip()] = value.strip()
     return info
 
 
-def check_output(args, env):
-    output = subprocess.Popen(
-        args, stdout=subprocess.PIPE, env=env
-    ).communicate()[0]
-    return six.text_type(output.decode('utf-8'))
+def _check_output(args, env):
+    output = subprocess.Popen(args, stdout=subprocess.PIPE, env=env).communicate()[0]
+    return six.text_type(output.decode("utf-8"))
 
 
-@info_dict(operating_system='Darwin')
+@info_dict(operating_system="Darwin")
 def sysctl_info_dict():
     """Returns a raw info dictionary parsing the output of sysctl."""
     # Make sure that /sbin and /usr/sbin are in PATH as sysctl is
     # usually found there
     child_environment = dict(os.environ.items())
-    search_paths = child_environment.get('PATH', '').split(os.pathsep)
-    for additional_path in ('/sbin', '/usr/sbin'):
+    search_paths = child_environment.get("PATH", "").split(os.pathsep)
+    for additional_path in ("/sbin", "/usr/sbin"):
         if additional_path not in search_paths:
             search_paths.append(additional_path)
-    child_environment['PATH'] = os.pathsep.join(search_paths)
+    child_environment["PATH"] = os.pathsep.join(search_paths)
 
     def sysctl(*args):
-        return check_output(
-            ['sysctl'] + list(args), env=child_environment
-        ).strip()
+        return _check_output(["sysctl"] + list(args), env=child_environment).strip()
 
-    flags = (sysctl('-n', 'machdep.cpu.features').lower() + ' '
-             + sysctl('-n', 'machdep.cpu.leaf7_features').lower())
+    flags = (
+        sysctl("-n", "machdep.cpu.features").lower()
+        + " "
+        + sysctl("-n", "machdep.cpu.leaf7_features").lower()
+    )
     info = {
-        'vendor_id': sysctl('-n', 'machdep.cpu.vendor'),
-        'flags': flags,
-        'model': sysctl('-n', 'machdep.cpu.model'),
-        'model name': sysctl('-n', 'machdep.cpu.brand_string')
+        "vendor_id": sysctl("-n", "machdep.cpu.vendor"),
+        "flags": flags,
+        "model": sysctl("-n", "machdep.cpu.model"),
+        "model name": sysctl("-n", "machdep.cpu.brand_string"),
     }
     return info
 
@@ -117,16 +118,16 @@ def adjust_raw_flags(info):
     slightly different representations.
     """
     # Flags detected on Darwin turned to their linux counterpart
-    flags = info.get('flags', [])
-    d2l = targets_json['conversions']['darwin_flags']
+    flags = info.get("flags", [])
+    d2l = TARGETS_JSON["conversions"]["darwin_flags"]
     for darwin_flag, linux_flag in d2l.items():
         if darwin_flag in flags:
-            info['flags'] += ' ' + linux_flag
+            info["flags"] += " " + linux_flag
 
 
 def adjust_raw_vendor(info):
     """Adjust the vendor field to make it human readable"""
-    if 'CPU implementer' not in info:
+    if "CPU implementer" not in info:
         return
 
     # Mapping numeric codes to vendor (ARM). This list is a merge from
@@ -136,10 +137,10 @@ def adjust_raw_vendor(info):
     # https://developer.arm.com/docs/ddi0487/latest/arm-architecture-reference-manual-armv8-for-armv8-a-architecture-profile
     # https://github.com/gcc-mirror/gcc/blob/master/gcc/config/aarch64/aarch64-cores.def
     # https://patchwork.kernel.org/patch/10524949/
-    arm_vendors = targets_json['conversions']['arm_vendors']
-    arm_code = info['CPU implementer']
+    arm_vendors = TARGETS_JSON["conversions"]["arm_vendors"]
+    arm_code = info["CPU implementer"]
     if arm_code in arm_vendors:
-        info['CPU implementer'] = arm_vendors[arm_code]
+        info["CPU implementer"] = arm_vendors[arm_code]
 
 
 def raw_info_dictionary():
@@ -148,12 +149,13 @@ def raw_info_dictionary():
     This function calls all the viable factories one after the other until
     there's one that is able to produce the requested information.
     """
+    # pylint: disable=broad-except
     info = {}
-    for factory in info_factory[platform.system()]:
+    for factory in INFO_FACTORY[platform.system()]:
         try:
             info = factory()
-        except Exception as e:
-            warnings.warn(str(e))
+        except Exception as exc:
+            warnings.warn(str(exc))
 
         if info:
             adjust_raw_flags(info)
@@ -173,9 +175,10 @@ def compatible_microarchitectures(info):
     architecture_family = platform.machine()
     # If a tester is not registered, be conservative and assume no known
     # target is compatible with the host
-    tester = compatibility_checks.get(architecture_family, lambda x, y: False)
-    return [x for x in targets.values() if tester(info, x)] or \
-           [generic_microarchitecture(architecture_family)]
+    tester = COMPATIBILITY_CHECKS.get(architecture_family, lambda x, y: False)
+    return [x for x in TARGETS.values() if tester(info, x)] or [
+        generic_microarchitecture(architecture_family)
+    ]
 
 
 def host():
@@ -188,7 +191,9 @@ def host():
 
     # Reverse sort of the depth for the inheritance tree among only targets we
     # can use. This gets the newest target we satisfy.
-    return sorted(candidates, key=lambda t: len(t.ancestors), reverse=True)[0]
+    return sorted(
+        candidates, key=lambda t: (len(t.ancestors), len(t.features)), reverse=True
+    )[0]
 
 
 def compatibility_check(architecture_family):
@@ -207,50 +212,59 @@ def compatibility_check(architecture_family):
         architecture_family = (architecture_family,)
 
     def decorator(func):
+        # pylint: disable=fixme
         # TODO: on removal of Python 2.6 support this can be re-written as
         # TODO: an update +  a dict comprehension
         for arch_family in architecture_family:
-            compatibility_checks[arch_family] = func
+            COMPATIBILITY_CHECKS[arch_family] = func
 
         return func
 
     return decorator
 
 
-@compatibility_check(architecture_family=('ppc64le', 'ppc64'))
+@compatibility_check(architecture_family=("ppc64le", "ppc64"))
 def compatibility_check_for_power(info, target):
+    """Compatibility check for PPC64 and PPC64LE architectures."""
     basename = platform.machine()
-    generation_match = re.search(r'POWER(\d+)', info.get('cpu', ''))
+    generation_match = re.search(r"POWER(\d+)", info.get("cpu", ""))
     generation = int(generation_match.group(1))
 
     # We can use a target if it descends from our machine type and our
     # generation (9 for POWER9, etc) is at least its generation.
-    arch_root = targets[basename]
-    return (target == arch_root or arch_root in target.ancestors) \
-        and target.generation <= generation
+    arch_root = TARGETS[basename]
+    return (
+        target == arch_root or arch_root in target.ancestors
+    ) and target.generation <= generation
 
 
-@compatibility_check(architecture_family='x86_64')
+@compatibility_check(architecture_family="x86_64")
 def compatibility_check_for_x86_64(info, target):
-    basename = 'x86_64'
-    vendor = info.get('vendor_id', 'generic')
-    features = set(info.get('flags', '').split())
+    """Compatibility check for x86_64 architectures."""
+    basename = "x86_64"
+    vendor = info.get("vendor_id", "generic")
+    features = set(info.get("flags", "").split())
 
     # We can use a target if it descends from our machine type, is from our
     # vendor, and we have all of its features
-    arch_root = targets[basename]
-    return (target == arch_root or arch_root in target.ancestors) \
-        and (target.vendor == vendor or target.vendor == 'generic') \
+    arch_root = TARGETS[basename]
+    return (
+        (target == arch_root or arch_root in target.ancestors)
+        and (target.vendor == vendor or target.vendor == "generic")
         and target.features.issubset(features)
+    )
 
 
-@compatibility_check(architecture_family='aarch64')
+@compatibility_check(architecture_family="aarch64")
 def compatibility_check_for_aarch64(info, target):
-    basename = 'aarch64'
-    features = set(info.get('Features', '').split())
-    vendor = info.get('CPU implementer', 'generic')
-
-    arch_root = targets[basename]
-    return (target == arch_root or arch_root in target.ancestors) \
-        and (target.vendor == vendor or target.vendor == 'generic') \
+    """Compatibility check for AARCH64 architectures."""
+    basename = "aarch64"
+    features = set(info.get("Features", "").split())
+    vendor = info.get("CPU implementer", "generic")
+
+    arch_root = TARGETS[basename]
+    return (
+        (target == arch_root or arch_root in target.ancestors)
+        and (target.vendor == vendor or target.vendor == "generic")
         and target.features.issubset(features)
+    )
diff --git a/lib/spack/llnl/util/cpu/microarchitecture.py b/lib/spack/external/archspec/cpu/microarchitecture.py
index 284bfebb7e..1b4f6485d5 100644
--- a/lib/spack/llnl/util/cpu/microarchitecture.py
+++ b/lib/spack/external/archspec/cpu/microarchitecture.py
@@ -1,81 +1,81 @@
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
-# Spack Project Developers. See the top-level COPYRIGHT file for details.
+# Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+# Archspec Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
+"""Types and functions to manage information
+on CPU microarchitectures.
+"""
+# pylint: disable=useless-object-inheritance
 import functools
 import platform
 import re
 import warnings
 
-try:
-    from collections.abc import Sequence  # novm
-except ImportError:
-    from collections import Sequence
-
 import six
 
-import llnl.util
-import llnl.util.cpu.alias
-import llnl.util.cpu.schema
-
+import archspec
+import archspec.cpu.alias
+import archspec.cpu.schema
+from .alias import FEATURE_ALIASES
 from .schema import LazyDictionary
-from .alias import feature_aliases
 
 
 def coerce_target_names(func):
     """Decorator that automatically converts a known target name to a proper
     Microarchitecture object.
     """
+
     @functools.wraps(func)
     def _impl(self, other):
         if isinstance(other, six.string_types):
-            if other not in targets:
+            if other not in TARGETS:
                 msg = '"{0}" is not a valid target name'
                 raise ValueError(msg.format(other))
-            other = targets[other]
+            other = TARGETS[other]
 
         return func(self, other)
+
     return _impl
 
 
 class Microarchitecture(object):
-    #: Aliases for micro-architecture's features
-    feature_aliases = feature_aliases
+    """Represents a specific CPU micro-architecture.
 
-    def __init__(
-            self, name, parents, vendor, features, compilers, generation=0
-    ):
-        """Represents a specific CPU micro-architecture.
+    Args:
+        name (str): name of the micro-architecture (e.g. skylake).
+        parents (list): list of parents micro-architectures, if any.
+            Parenthood is considered by cpu features and not
+            chronologically. As such each micro-architecture is
+            compatible with its ancestors. For example "skylake",
+            which has "broadwell" as a parent, supports running binaries
+            optimized for "broadwell".
+        vendor (str): vendor of the micro-architecture
+        features (list of str): supported CPU flags. Note that the semantic
+            of the flags in this field might vary among architectures, if
+            at all present. For instance x86_64 processors will list all
+            the flags supported by a given CPU while Arm processors will
+            list instead only the flags that have been added on top of the
+            base model for the current micro-architecture.
+        compilers (dict): compiler support to generate tuned code for this
+            micro-architecture. This dictionary has as keys names of
+            supported compilers, while values are list of dictionaries
+            with fields:
+
+            * name: name of the micro-architecture according to the
+                compiler. This is the name passed to the ``-march`` option
+                or similar. Not needed if the name is the same as that
+                passed in as argument above.
+            * versions: versions that support this micro-architecture.
+
+        generation (int): generation of the micro-architecture, if
+            relevant.
+    """
 
-        Args:
-            name (str): name of the micro-architecture (e.g. skylake).
-            parents (list): list of parents micro-architectures, if any.
-                Parenthood is considered by cpu features and not
-                chronologically. As such each micro-architecture is
-                compatible with its ancestors. For example "skylake",
-                which has "broadwell" as a parent, supports running binaries
-                optimized for "broadwell".
-            vendor (str): vendor of the micro-architecture
-            features (list of str): supported CPU flags. Note that the semantic
-                of the flags in this field might vary among architectures, if
-                at all present. For instance x86_64 processors will list all
-                the flags supported by a given CPU while Arm processors will
-                list instead only the flags that have been added on top of the
-                base model for the current micro-architecture.
-            compilers (dict): compiler support to generate tuned code for this
-                micro-architecture. This dictionary has as keys names of
-                supported compilers, while values are list of dictionaries
-                with fields:
-
-                * name: name of the micro-architecture according to the
-                    compiler. This is the name passed to the ``-march`` option
-                    or similar. Not needed if the name is the same as that
-                    passed in as argument above.
-                * versions: versions that support this micro-architecture.
-
-            generation (int): generation of the micro-architecture, if
-                relevant.
-        """
+    # pylint: disable=too-many-arguments
+    #: Aliases for micro-architecture's features
+    feature_aliases = FEATURE_ALIASES
+
+    def __init__(self, name, parents, vendor, features, compilers, generation=0):
         self.name = name
         self.parents = parents
         self.vendor = vendor
@@ -85,6 +85,7 @@ class Microarchitecture(object):
 
     @property
     def ancestors(self):
+        """All the ancestors of this microarchitecture."""
         value = self.parents[:]
         for parent in self.parents:
             value.extend(a for a in parent.ancestors if a not in value)
@@ -101,12 +102,14 @@ class Microarchitecture(object):
         if not isinstance(other, Microarchitecture):
             return NotImplemented
 
-        return (self.name == other.name and
-                self.vendor == other.vendor and
-                self.features == other.features and
-                self.ancestors == other.ancestors and
-                self.compilers == other.compilers and
-                self.generation == other.generation)
+        return (
+            self.name == other.name
+            and self.vendor == other.vendor
+            and self.features == other.features
+            and self.ancestors == other.ancestors
+            and self.compilers == other.compilers
+            and self.generation == other.generation
+        )
 
     @coerce_target_names
     def __ne__(self, other):
@@ -136,8 +139,10 @@ class Microarchitecture(object):
 
     def __repr__(self):
         cls_name = self.__class__.__name__
-        fmt = cls_name + '({0.name!r}, {0.parents!r}, {0.vendor!r}, ' \
-                         '{0.features!r}, {0.compilers!r}, {0.generation!r})'
+        fmt = (
+            cls_name + "({0.name!r}, {0.parents!r}, {0.vendor!r}, "
+            "{0.features!r}, {0.compilers!r}, {0.generation!r})"
+        )
         return fmt.format(self)
 
     def __str__(self):
@@ -146,7 +151,7 @@ class Microarchitecture(object):
     def __contains__(self, feature):
         # Feature must be of a string type, so be defensive about that
         if not isinstance(feature, six.string_types):
-            msg = 'only objects of string types are accepted [got {0}]'
+            msg = "only objects of string types are accepted [got {0}]"
             raise TypeError(msg.format(str(type(feature))))
 
         # Here we look first in the raw features, and fall-back to
@@ -155,9 +160,7 @@ class Microarchitecture(object):
             return True
 
         # Check if the alias is defined, if not it will return False
-        match_alias = Microarchitecture.feature_aliases.get(
-            feature, lambda x: False
-        )
+        match_alias = Microarchitecture.feature_aliases.get(feature, lambda x: False)
         return match_alias(self)
 
     @property
@@ -165,7 +168,7 @@ class Microarchitecture(object):
         """Returns the architecture family a given target belongs to"""
         roots = [x for x in [self] + self.ancestors if not x.ancestors]
         msg = "a target is expected to belong to just one architecture family"
-        msg += "[found {0}]".format(', '.join(str(x) for x in roots))
+        msg += "[found {0}]".format(", ".join(str(x) for x in roots))
         assert len(roots) == 1, msg
 
         return roots.pop()
@@ -178,13 +181,11 @@ class Microarchitecture(object):
                 items instead of the dictionary
         """
         list_of_items = [
-            ('name', str(self.name)),
-            ('vendor', str(self.vendor)),
-            ('features', sorted(
-                str(x) for x in self.features
-            )),
-            ('generation', self.generation),
-            ('parents', [str(x) for x in self.parents])
+            ("name", str(self.name)),
+            ("vendor", str(self.vendor)),
+            ("features", sorted(str(x) for x in self.features)),
+            ("generation", self.generation),
+            ("parents", [str(x) for x in self.parents]),
         ]
         if return_list_of_items:
             return list_of_items
@@ -204,19 +205,18 @@ class Microarchitecture(object):
             compiler (str): name of the compiler to be used
             version (str): version of the compiler to be used
         """
-        # If we don't have information on compiler at all
-        # return an empty string
+        # If we don't have information on compiler at all return an empty string
         if compiler not in self.family.compilers:
-            return ''
+            return ""
 
         # If we have information but it stops before this
         # microarchitecture, fall back to the best known target
         if compiler not in self.compilers:
-            best_target = [
-                x for x in self.ancestors if compiler in x.compilers
-            ][0]
-            msg = ("'{0}' compiler is known to optimize up to the '{1}'"
-                   " microarchitecture in the '{2}' architecture family")
+            best_target = [x for x in self.ancestors if compiler in x.compilers][0]
+            msg = (
+                "'{0}' compiler is known to optimize up to the '{1}'"
+                " microarchitecture in the '{2}' architecture family"
+            )
             msg = msg.format(compiler, best_target, best_target.family)
             raise UnsupportedMicroarchitecture(msg)
 
@@ -224,20 +224,17 @@ class Microarchitecture(object):
         # version being used
         compiler_info = self.compilers[compiler]
 
-        # Normalize the entries to have a uniform treatment in the code below
-        if not isinstance(compiler_info, Sequence):
-            compiler_info = [compiler_info]
-
         def satisfies_constraint(entry, version):
-            min_version, max_version = entry['versions'].split(':')
+            min_version, max_version = entry["versions"].split(":")
 
-            # Extract numeric part of the version
+            # Check version suffixes
             min_version, _ = version_components(min_version)
             max_version, _ = version_components(max_version)
             version, _ = version_components(version)
 
             # Assume compiler versions fit into semver
-            tuplify = lambda x: tuple(int(y) for y in x.split('.'))
+            def tuplify(ver):
+                return tuple(int(y) for y in ver.split("."))
 
             version = tuplify(version)
             if min_version:
@@ -254,23 +251,29 @@ class Microarchitecture(object):
 
         for compiler_entry in compiler_info:
             if satisfies_constraint(compiler_entry, version):
-                flags_fmt = compiler_entry['flags']
+                flags_fmt = compiler_entry["flags"]
                 # If there's no field name, use the name of the
                 # micro-architecture
-                compiler_entry.setdefault('name', self.name)
+                compiler_entry.setdefault("name", self.name)
 
                 # Check if we need to emit a warning
-                warning_message = compiler_entry.get('warnings', None)
+                warning_message = compiler_entry.get("warnings", None)
                 if warning_message:
                     warnings.warn(warning_message)
 
                 flags = flags_fmt.format(**compiler_entry)
                 return flags
 
-        msg = ("cannot produce optimized binary for micro-architecture '{0}'"
-               " with {1}@{2} [supported compiler versions are {3}]")
-        msg = msg.format(self.name, compiler, version,
-                         ', '.join([x['versions'] for x in compiler_info]))
+        msg = (
+            "cannot produce optimized binary for micro-architecture '{0}'"
+            " with {1}@{2} [supported compiler versions are {3}]"
+        )
+        msg = msg.format(
+            self.name,
+            compiler,
+            version,
+            ", ".join([x["versions"] for x in compiler_info]),
+        )
         raise UnsupportedMicroarchitecture(msg)
 
 
@@ -281,7 +284,7 @@ def generic_microarchitecture(name):
         name (str): name of the micro-architecture
     """
     return Microarchitecture(
-        name, parents=[], vendor='generic', features=[], compilers={}
+        name, parents=[], vendor="generic", features=[], compilers={}
     )
 
 
@@ -289,15 +292,15 @@ def version_components(version):
     """Decomposes the version passed as input in version number and
     suffix and returns them.
 
-    If the version number of the suffix are not present, an empty
+    If the version number or the suffix are not present, an empty
     string is returned.
 
     Args:
         version (str): version to be decomposed into its components
     """
-    match = re.match(r'([\d.]*)(-?)(.*)', str(version))
+    match = re.match(r"([\d.]*)(-?)(.*)", str(version))
     if not match:
-        return '', ''
+        return "", ""
 
     version_number = match.group(1)
     suffix = match.group(3)
@@ -309,7 +312,7 @@ def _known_microarchitectures():
     """Returns a dictionary of the known micro-architectures. If the
     current host platform is unknown adds it too as a generic target.
     """
-
+    # pylint: disable=fixme
     # TODO: Simplify this logic using object_pairs_hook to OrderedDict
     # TODO: when we stop supporting python2.6
 
@@ -326,44 +329,40 @@ def _known_microarchitectures():
         values = data[name]
 
         # Get direct parents of target
-        parent_names = values['from']
-        if isinstance(parent_names, six.string_types):
-            parent_names = [parent_names]
-        if parent_names is None:
-            parent_names = []
-        for p in parent_names:
+        parent_names = values["from"]
+        for parent in parent_names:
             # Recursively fill parents so they exist before we add them
-            if p in targets:
+            if parent in targets:
                 continue
-            fill_target_from_dict(p, data, targets)
-        parents = [targets.get(p) for p in parent_names]
+            fill_target_from_dict(parent, data, targets)
+        parents = [targets.get(parent) for parent in parent_names]
 
-        vendor = values['vendor']
-        features = set(values['features'])
-        compilers = values.get('compilers', {})
-        generation = values.get('generation', 0)
+        vendor = values["vendor"]
+        features = set(values["features"])
+        compilers = values.get("compilers", {})
+        generation = values.get("generation", 0)
 
         targets[name] = Microarchitecture(
             name, parents, vendor, features, compilers, generation
         )
 
-    targets = {}
-    data = llnl.util.cpu.schema.targets_json['microarchitectures']
+    known_targets = {}
+    data = archspec.cpu.schema.TARGETS_JSON["microarchitectures"]
     for name in data:
-        if name in targets:
+        if name in known_targets:
             # name was already brought in as ancestor to a target
             continue
-        fill_target_from_dict(name, data, targets)
+        fill_target_from_dict(name, data, known_targets)
 
     # Add the host platform if not present
     host_platform = platform.machine()
-    targets.setdefault(host_platform, generic_microarchitecture(host_platform))
+    known_targets.setdefault(host_platform, generic_microarchitecture(host_platform))
 
-    return targets
+    return known_targets
 
 
 #: Dictionary of known micro-architectures
-targets = LazyDictionary(_known_microarchitectures)
+TARGETS = LazyDictionary(_known_microarchitectures)
 
 
 class UnsupportedMicroarchitecture(ValueError):
diff --git a/lib/spack/external/archspec/cpu/schema.py b/lib/spack/external/archspec/cpu/schema.py
new file mode 100644
index 0000000000..4a9299271b
--- /dev/null
+++ b/lib/spack/external/archspec/cpu/schema.py
@@ -0,0 +1,70 @@
+# Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+# Archspec Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+"""Global objects with the content of the microarchitecture
+JSON file and its schema
+"""
+import json
+import os.path
+
+try:
+    from collections.abc import MutableMapping  # novm
+except ImportError:
+    from collections import MutableMapping
+
+
+class LazyDictionary(MutableMapping):
+    """Lazy dictionary that gets constructed on first access to any object key
+
+    Args:
+        factory (callable): factory function to construct the dictionary
+    """
+
+    def __init__(self, factory, *args, **kwargs):
+        self.factory = factory
+        self.args = args
+        self.kwargs = kwargs
+        self._data = None
+
+    @property
+    def data(self):
+        """Returns the lazily constructed dictionary"""
+        if self._data is None:
+            self._data = self.factory(*self.args, **self.kwargs)
+        return self._data
+
+    def __getitem__(self, key):
+        return self.data[key]
+
+    def __setitem__(self, key, value):
+        self.data[key] = value
+
+    def __delitem__(self, key):
+        del self.data[key]
+
+    def __iter__(self):
+        return iter(self.data)
+
+    def __len__(self):
+        return len(self.data)
+
+
+def _load_json_file(json_file):
+    json_dir = os.path.join(os.path.dirname(__file__), "..", "json", "cpu")
+    json_dir = os.path.abspath(json_dir)
+
+    def _factory():
+        filename = os.path.join(json_dir, json_file)
+        with open(filename, "r") as file:
+            return json.load(file)
+
+    return _factory
+
+
+#: In memory representation of the data in microarchitectures.json,
+#: loaded on first access
+TARGETS_JSON = LazyDictionary(_load_json_file("microarchitectures.json"))
+
+#: JSON schema for microarchitectures.json, loaded on first access
+SCHEMA = LazyDictionary(_load_json_file("microarchitectures_schema.json"))
diff --git a/lib/spack/external/archspec/json/COPYRIGHT b/lib/spack/external/archspec/json/COPYRIGHT
new file mode 100644
index 0000000000..4164e98de7
--- /dev/null
+++ b/lib/spack/external/archspec/json/COPYRIGHT
@@ -0,0 +1,22 @@
+Intellectual Property Notice
+------------------------------
+
+Archspec is licensed under the Apache License, Version 2.0 (LICENSE-APACHE
+or http://www.apache.org/licenses/LICENSE-2.0) or the MIT license,
+(LICENSE-MIT or http://opensource.org/licenses/MIT), at your option.
+
+Copyrights and patents in the Archspec project are retained by contributors.
+No copyright assignment is required to contribute to Archspec.
+
+
+SPDX usage
+------------
+
+Individual files contain SPDX tags instead of the full license text.
+This enables machine processing of license information based on the SPDX
+License Identifiers that are available here: https://spdx.org/licenses/
+
+Files that are dual-licensed as Apache-2.0 OR MIT contain the following
+text in the license header:
+
+    SPDX-License-Identifier: (Apache-2.0 OR MIT)
diff --git a/lib/spack/external/archspec/json/LICENSE-APACHE b/lib/spack/external/archspec/json/LICENSE-APACHE
new file mode 100644
index 0000000000..d645695673
--- /dev/null
+++ b/lib/spack/external/archspec/json/LICENSE-APACHE
@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
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+
+      "Legal Entity" shall mean the union of the acting entity and all
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+      direction or management of such entity, whether by contract or
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+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
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+
+      "Object" form shall mean any form resulting from mechanical
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+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
diff --git a/lib/spack/external/archspec/json/LICENSE-MIT b/lib/spack/external/archspec/json/LICENSE-MIT
new file mode 100644
index 0000000000..03be635ad5
--- /dev/null
+++ b/lib/spack/external/archspec/json/LICENSE-MIT
@@ -0,0 +1,20 @@
+Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+Archspec Project Developers. See the top-level COPYRIGHT file for details.
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
diff --git a/lib/spack/external/archspec/json/NOTICE b/lib/spack/external/archspec/json/NOTICE
new file mode 100644
index 0000000000..3737d5a86d
--- /dev/null
+++ b/lib/spack/external/archspec/json/NOTICE
@@ -0,0 +1,21 @@
+This work was produced under the auspices of the U.S. Department of
+Energy by Lawrence Livermore National Laboratory under Contract
+DE-AC52-07NA27344.
+
+This work was prepared as an account of work sponsored by an agency of
+the United States Government. Neither the United States Government nor
+Lawrence Livermore National Security, LLC, nor any of their employees
+makes any warranty, expressed or implied, or assumes any legal liability
+or responsibility for the accuracy, completeness, or usefulness of any
+information, apparatus, product, or process disclosed, or represents that
+its use would not infringe privately owned rights.
+
+Reference herein to any specific commercial product, process, or service
+by trade name, trademark, manufacturer, or otherwise does not necessarily
+constitute or imply its endorsement, recommendation, or favoring by the
+United States Government or Lawrence Livermore National Security, LLC.
+
+The views and opinions of authors expressed herein do not necessarily
+state or reflect those of the United States Government or Lawrence
+Livermore National Security, LLC, and shall not be used for advertising
+or product endorsement purposes.
diff --git a/lib/spack/external/archspec/json/README.md b/lib/spack/external/archspec/json/README.md
new file mode 100644
index 0000000000..e01b75f31a
--- /dev/null
+++ b/lib/spack/external/archspec/json/README.md
@@ -0,0 +1,36 @@
+[![](https://github.com/archspec/archspec-json/workflows/JSON%20Validation/badge.svg)](https://github.com/archspec/archspec-json/actions)
+
+# Archspec-json
+
+The [archspec-json](https://github.com/archspec/archspec-json) repository is part of the
+[Archspec](https://github.com/archspec) project. It contains data on various architectural
+aspects of a platform stored in JSON format and is meant to be used as a base to develop
+language specific APIs.
+
+Currently the repository contains the following JSON files:
+```console
+.
+├── COPYRIGHT
+└── cpu
+    ├── microarchitectures.json         # Contains information on CPU microarchitectures
+    └── microarchitectures_schema.json  # Schema for the file above
+ ```
+
+
+## License
+
+Archspec is distributed under the terms of both the MIT license and the
+Apache License (Version 2.0). Users may choose either license, at their
+option.
+
+All new contributions must be made under both the MIT and Apache-2.0
+licenses.
+
+See [LICENSE-MIT](https://github.com/archspec/archspec-json/blob/master/LICENSE-MIT),
+[LICENSE-APACHE](https://github.com/archspec/archspec-json/blob/master/LICENSE-APACHE),
+[COPYRIGHT](https://github.com/archspec/archspec-json/blob/master/COPYRIGHT), and
+[NOTICE](https://github.com/archspec/archspec-json/blob/master/NOTICE) for details.
+
+SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+LLNL-CODE-811653
diff --git a/lib/spack/llnl/util/cpu/microarchitectures.json b/lib/spack/external/archspec/json/cpu/microarchitectures.json
index 3742d122e9..b957f6c5b3 100644
--- a/lib/spack/llnl/util/cpu/microarchitectures.json
+++ b/lib/spack/external/archspec/json/cpu/microarchitectures.json
@@ -1,24 +1,24 @@
 {
   "microarchitectures": {
     "x86": {
-      "from": null,
+      "from": [],
       "vendor": "generic",
       "features": []
     },
     "i686": {
-      "from": "x86",
+      "from": ["x86"],
       "vendor": "GenuineIntel",
       "features": []
     },
     "pentium2": {
-      "from": "i686",
+      "from": ["i686"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx"
       ]
     },
     "pentium3": {
-      "from": "pentium2",
+      "from": ["pentium2"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -26,7 +26,7 @@
       ]
     },
     "pentium4": {
-      "from": "pentium3",
+      "from": ["pentium3"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -35,7 +35,7 @@
       ]
     },
     "prescott": {
-      "from": "pentium4",
+      "from": ["pentium4"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -45,7 +45,7 @@
       ]
     },
     "x86_64": {
-      "from": null,
+      "from": [],
       "vendor": "generic",
       "features": [],
       "compilers": {
@@ -75,15 +75,17 @@
             "flags": "-march={name} -mtune=generic"
           }
         ],
-        "intel": {
-          "versions": ":",
-          "name": "pentium4",
-          "flags": "-march={name} -mtune=generic"
-        }
+        "intel": [
+          {
+            "versions": ":",
+            "name": "pentium4",
+            "flags": "-march={name} -mtune=generic"
+          }
+        ]
       }
     },
     "nocona": {
-      "from": "x86_64",
+      "from": ["x86_64"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -92,23 +94,35 @@
         "sse3"
       ],
       "compilers": {
-        "gcc": {
-          "versions": "4.0.4:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "16.0:",
-          "name": "pentium4",
-          "flags": "-march={name} -mtune=generic"
-        }
+        "gcc": [
+          {
+            "versions": "4.0.4:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "16.0:",
+            "name": "pentium4",
+            "flags": "-march={name} -mtune=generic"
+          }
+        ]
       }
     },
     "core2": {
-      "from": "nocona",
+      "from": ["nocona"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -117,22 +131,34 @@
         "ssse3"
       ],
       "compilers": {
-        "gcc": {
-          "versions": "4.3.0:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "16.0:",
-          "flags": "-march={name} -mtune={name}}"
-        }
+        "gcc": [
+          {
+            "versions": "4.3.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "16.0:",
+            "flags": "-march={name} -mtune={name}}"
+          }
+        ]
       }
     },
     "nehalem": {
-      "from": "core2",
+      "from": ["core2"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -155,19 +181,29 @@
             "flags": "-march={name} -mtune={name}"
           }
         ],
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "16.0:",
-          "name": "corei7",
-          "flags": "-march={name} -mtune={name}"
-        }
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "16.0:",
+            "name": "corei7",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ]
       }
     },
     "westmere": {
-      "from": "nehalem",
+      "from": ["nehalem"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -181,23 +217,35 @@
         "pclmulqdq"
       ],
       "compilers": {
-        "gcc": {
-          "versions": "4.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "16.0:",
-          "name": "corei7",
-          "flags": "-march={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "versions": "4.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "16.0:",
+            "name": "corei7",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ]
       }
     },
     "sandybridge": {
-      "from": "westmere",
+      "from": ["westmere"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -223,10 +271,18 @@
             "flags": "-march={name} -mtune={name}"
           }
         ],
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
         "intel": [
           {
             "versions": "16.0:17.9.0",
@@ -241,7 +297,7 @@
       }
     },
     "ivybridge": {
-      "from": "sandybridge",
+      "from": ["sandybridge"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -269,10 +325,18 @@
             "flags": "-march={name} -mtune={name}"
           }
         ],
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
         "intel": [
           {
             "versions": "16.0:17.9.0",
@@ -287,7 +351,7 @@
       }
     },
     "haswell": {
-      "from": "ivybridge",
+      "from": ["ivybridge"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -320,10 +384,18 @@
             "flags": "-march={name} -mtune={name}"
           }
         ],
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
         "intel": [
           {
             "versions": "16.0:17.9.0",
@@ -338,7 +410,7 @@
       }
     },
     "broadwell": {
-      "from": "haswell",
+      "from": ["haswell"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -362,22 +434,34 @@
         "adx"
       ],
       "compilers": {
-        "gcc": {
-          "versions": "4.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "18.0:",
-          "flags": "-march={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "versions": "4.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "18.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ]
       }
     },
     "skylake": {
-      "from": "broadwell",
+      "from": ["broadwell"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -404,22 +488,34 @@
         "xsaveopt"
       ],
       "compilers": {
-        "gcc": {
-          "versions": "6.0:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "18.0:",
-          "flags": "-march={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "versions": "6.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "18.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ]
       }
     },
     "mic_knl": {
-      "from": "broadwell",
+      "from": ["broadwell"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -448,25 +544,37 @@
         "avx512cd"
       ],
       "compilers": {
-        "gcc": {
-          "versions": "5.1:",
-          "name": "knl",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "name": "knl",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "18.0:",
-          "name": "knl",
-          "flags": "-march={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "versions": "5.1:",
+            "name": "knl",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "name": "knl",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "18.0:",
+            "name": "knl",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ]
       }
     },
     "skylake_avx512": {
-      "from": "skylake",
+      "from": ["skylake"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -499,25 +607,37 @@
         "avx512cd"
       ],
       "compilers": {
-        "gcc": {
-          "name": "skylake-avx512",
-          "versions": "6.0:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "name": "skylake-avx512",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "18.0:",
-          "name": "skylake-avx512",
-          "flags": "-march={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "name": "skylake-avx512",
+            "versions": "6.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "name": "skylake-avx512",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "18.0:",
+            "name": "skylake-avx512",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ]
       }
     },
     "cannonlake": {
-      "from": "skylake",
+      "from": ["skylake"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -553,22 +673,34 @@
         "umip"
       ],
       "compilers": {
-        "gcc": {
-          "versions": "8.0:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "18.0:",
-          "flags": "-march={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "18.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ]
       }
     },
     "cascadelake": {
-      "from": "skylake_avx512",
+      "from": ["skylake_avx512"],
       "vendor": "GenuineIntel",
       "features": [
         "mmx",
@@ -602,18 +734,30 @@
         "avx512_vnni"
       ],
       "compilers": {
-        "gcc": {
-          "versions": "9.0:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "8.0:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "19.0:",
-          "flags": "-march={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "versions": "9.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "apple-clang": [
+          {
+            "versions": "11.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "19.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ]
       }
     },
     "icelake": {
@@ -654,6 +798,7 @@
         "avx512ifma",
         "sha_ni",
         "umip",
+        "clwb",
         "rdpid",
         "gfni",
         "avx512_vbmi2",
@@ -664,11 +809,13 @@
         "vaes"
       ],
       "compilers": {
-        "gcc": {
-          "name": "icelake-client",
-          "versions": "8.0:",
-          "flags": "-march={name} -mtune={name}"
-        },
+        "gcc": [
+          {
+            "name": "icelake-client",
+            "versions": "8.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
         "clang": [
           {
             "versions": "7.0:",
@@ -680,15 +827,28 @@
             "flags": "-march={name} -mtune={name}"
           }
         ],
-        "intel": {
-          "versions": "18.0:",
-          "name": "icelake-client",
-          "flags": "-march={name} -mtune={name}"
-        }
+        "apple-clang": [
+          {
+            "versions": "10.0.1:",
+            "name": "icelake-client",
+            "flags": "-march={name} -mtune={name}"
+          },
+          {
+            "versions": "10.0.0:10.0.99",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "18.0:",
+            "name": "icelake-client",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ]
       }
     },
     "k10": {
-      "from": "x86_64",
+      "from": ["x86_64"],
       "vendor": "AuthenticAMD",
       "features": [
         "mmx",
@@ -701,25 +861,31 @@
         "3dnowext"
       ],
       "compilers": {
-        "gcc": {
-          "name": "amdfam10",
-          "versions": "4.3:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "name": "amdfam10",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "16.0:",
-          "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
-          "flags": "-msse2"
-        }
+        "gcc": [
+          {
+            "name": "amdfam10",
+            "versions": "4.3:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "name": "amdfam10",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "16.0:",
+            "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
+            "flags": "-msse2"
+          }
+        ]
       }
     },
     "bulldozer": {
-      "from": "x86_64",
+      "from": ["x86_64"],
       "vendor": "AuthenticAMD",
       "features": [
         "mmx",
@@ -738,25 +904,31 @@
         "sse4_2"
       ],
       "compilers": {
-        "gcc": {
-          "name": "bdver1",
-          "versions": "4.7:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "name": "bdver1",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "16.0:",
-          "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
-          "flags": "-msse3"
-        }
+        "gcc": [
+          {
+            "name": "bdver1",
+            "versions": "4.7:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "name": "bdver1",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "16.0:",
+            "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
+            "flags": "-msse3"
+          }
+        ]
       }
     },
     "piledriver": {
-      "from": "bulldozer",
+      "from": ["bulldozer"],
       "vendor": "AuthenticAMD",
       "features": [
         "mmx",
@@ -779,25 +951,31 @@
         "tbm"
       ],
       "compilers": {
-        "gcc": {
-          "name": "bdver2",
-          "versions": "4.7:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "name": "bdver2",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "16.0:",
-          "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
-          "flags": "-msse3"
-        }
+        "gcc": [
+          {
+            "name": "bdver2",
+            "versions": "4.7:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "name": "bdver2",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "16.0:",
+            "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
+            "flags": "-msse3"
+          }
+        ]
       }
     },
     "steamroller": {
-      "from": "piledriver",
+      "from": ["piledriver"],
       "vendor": "AuthenticAMD",
       "features": [
         "mmx",
@@ -821,25 +999,31 @@
         "tbm"
       ],
       "compilers": {
-        "gcc": {
-          "name": "bdver3",
-          "versions": "4.8:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "name": "bdver3",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "16.0:",
-          "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
-          "flags": "-msse4.2"
-        }
+        "gcc": [
+          {
+            "name": "bdver3",
+            "versions": "4.8:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "name": "bdver3",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "16.0:",
+            "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
+            "flags": "-msse4.2"
+          }
+        ]
       }
     },
     "excavator": {
-      "from": "steamroller",
+      "from": ["steamroller"],
       "vendor": "AuthenticAMD",
       "features": [
         "mmx",
@@ -866,26 +1050,32 @@
         "tbm"
       ],
       "compilers": {
-        "gcc": {
-          "name": "bdver4",
-          "versions": "4.9:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "name": "bdver4",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "16.0:",
-          "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
-          "name": "core-avx2",
-          "flags": "-march={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "name": "bdver4",
+            "versions": "4.9:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "name": "bdver4",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "16.0:",
+            "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
+            "name": "core-avx2",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ]
       }
     },
     "zen": {
-      "from": "x86_64",
+      "from": ["x86_64"],
       "vendor": "AuthenticAMD",
       "features": [
         "bmi1",
@@ -915,26 +1105,32 @@
         "popcnt"
       ],
       "compilers": {
-        "gcc": {
-          "name": "znver1",
-          "versions": "6.0:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "4.0:",
-          "name": "znver1",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "16.0:",
-          "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
-          "name": "core-avx2",
-          "flags": "-march={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "name": "znver1",
+            "versions": "6.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "4.0:",
+            "name": "znver1",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "16.0:",
+            "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
+            "name": "core-avx2",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ]
       }
     },
     "zen2": {
-      "from": "zen",
+      "from": ["zen"],
       "vendor": "AuthenticAMD",
       "features": [
         "bmi1",
@@ -965,58 +1161,72 @@
         "clwb"
       ],
       "compilers": {
-        "gcc": {
-          "name": "znver2",
-          "versions": "9.0:",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "9.0:",
-          "name": "znver2",
-          "flags": "-march={name} -mtune={name}"
-        },
-        "intel": {
-          "versions": "16.0:",
-          "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
-          "name": "core-avx2",
-          "flags": "-march={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "name": "znver2",
+            "versions": "9.0:",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "9.0:",
+            "name": "znver2",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ],
+        "intel": [
+          {
+            "versions": "16.0:",
+            "warnings": "Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors",
+            "name": "core-avx2",
+            "flags": "-march={name} -mtune={name}"
+          }
+        ]
       }
     },
     "ppc64": {
-      "from": null,
+      "from": [],
       "vendor": "generic",
       "features": [],
       "compilers": {
-        "gcc": {
-          "name": "powerpc64",
-          "versions": ":",
-          "flags": "-mcpu={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": ":",
-          "flags": "-mcpu={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "name": "powerpc64",
+            "versions": ":",
+            "flags": "-mcpu={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": ":",
+            "flags": "-mcpu={name} -mtune={name}"
+          }
+        ]
       }
     },
     "power7": {
-      "from": "ppc64",
+      "from": ["ppc64"],
       "vendor": "IBM",
       "generation": 7,
       "features": [],
       "compilers": {
-        "gcc": {
-          "versions": "4.4:",
-          "flags": "-mcpu={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-mcpu={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "versions": "4.4:",
+            "flags": "-mcpu={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-mcpu={name} -mtune={name}"
+          }
+        ]
       }
     },
     "power8": {
-      "from": "power7",
+      "from": ["power7"],
       "vendor": "IBM",
       "generation": 8,
       "features": [],
@@ -1032,46 +1242,56 @@
             "flags": "-mcpu={name} -mtune={name}"
           }
         ],
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-mcpu={name} -mtune={name}"
-        }
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-mcpu={name} -mtune={name}"
+          }
+        ]
       }
     },
     "power9": {
-      "from": "power8",
+      "from": ["power8"],
       "vendor": "IBM",
       "generation": 9,
       "features": [],
       "compilers": {
-        "gcc": {
-          "versions": "6.0:",
-          "flags": "-mcpu={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "flags": "-mcpu={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "versions": "6.0:",
+            "flags": "-mcpu={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "flags": "-mcpu={name} -mtune={name}"
+          }
+        ]
       }
     },
     "ppc64le": {
-      "from": null,
+      "from": [],
       "vendor": "generic",
       "features": [],
       "compilers": {
-        "gcc": {
-          "name": "powerpc64le",
-          "versions": "4.8:",
-          "flags": "-mcpu={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": ":",
-          "flags": "-mcpu={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "name": "powerpc64le",
+            "versions": "4.8:",
+            "flags": "-mcpu={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": ":",
+            "flags": "-mcpu={name} -mtune={name}"
+          }
+        ]
       }
     },
     "power8le": {
-      "from": "ppc64le",
+      "from": ["ppc64le"],
       "vendor": "IBM",
       "generation": 8,
       "features": [],
@@ -1089,50 +1309,60 @@
             "flags": "-mcpu={name} -mtune={name}"
           }
         ],
-        "clang": {
-          "versions": "3.9:",
-          "family": "ppc64le",
-          "name": "power8",
-          "flags": "-mcpu={name} -mtune={name}"
-        }
+        "clang": [
+          {
+            "versions": "3.9:",
+            "family": "ppc64le",
+            "name": "power8",
+            "flags": "-mcpu={name} -mtune={name}"
+          }
+        ]
       }
     },
     "power9le": {
-      "from": "power8le",
+      "from": ["power8le"],
       "vendor": "IBM",
       "generation": 9,
       "features": [],
       "compilers": {
-        "gcc": {
-          "name": "power9",
-          "versions": "6.0:",
-          "flags": "-mcpu={name} -mtune={name}"
-        },
-        "clang": {
-          "versions": "3.9:",
-          "family": "ppc64le",
-          "name": "power9",
-          "flags": "-mcpu={name} -mtune={name}"
-        }
+        "gcc": [
+          {
+            "name": "power9",
+            "versions": "6.0:",
+            "flags": "-mcpu={name} -mtune={name}"
+          }
+        ],
+        "clang": [
+          {
+            "versions": "3.9:",
+            "family": "ppc64le",
+            "name": "power9",
+            "flags": "-mcpu={name} -mtune={name}"
+          }
+        ]
       }
     },
     "aarch64": {
-      "from": null,
+      "from": [],
       "vendor": "generic",
       "features": [],
       "compilers": {
-        "gcc": {
-          "versions": "4.8.0:",
-          "flags": "-march=armv8-a -mtune=generic"
-        },
-        "clang": {
-          "versions": ":",
-          "flags": "-march=armv8-a -mtune=generic"
-        }
+        "gcc": [
+          {
+            "versions": "4.8.0:",
+            "flags": "-march=armv8-a -mtune=generic"
+          }
+        ],
+        "clang": [
+          {
+            "versions": ":",
+            "flags": "-march=armv8-a -mtune=generic"
+          }
+        ]
       }
     },
     "thunderx2": {
-      "from": "aarch64",
+      "from": ["aarch64"],
       "vendor": "Cavium",
       "features": [
         "fp",
@@ -1179,7 +1409,7 @@
       }
     },
     "a64fx": {
-      "from": "aarch64",
+      "from": ["aarch64"],
       "vendor": "Fujitsu",
       "features": [
         "fp",
@@ -1234,41 +1464,145 @@
         ]
       }
     },
+    "graviton": {
+      "from": ["aarch64"],
+      "vendor": "ARM",
+      "features": [
+          "fp",
+          "asimd",
+          "evtstrm",
+          "aes",
+          "pmull",
+          "sha1",
+          "sha2",
+          "crc32",
+          "cpuid"
+      ],
+      "compilers" : {
+          "gcc": [
+              {
+                  "versions": "4.8:4.8.9",
+                  "flags" : "-march=armv8-a"
+              },
+              {
+                  "versions": "4.9:5.9",
+                  "flags" : "-march=armv8-a+crc+crypto"
+              },
+              {
+                  "versions": "6:",
+                  "flags" : "-march==armv8-a+crc+crypto -mtune=cortex-a72"
+              }
+          ],
+          "clang" : [
+              {
+                  "versions": "3.9:",
+                  "flags" : "-march=armv8-a+crc+crypto"
+              }
+          ]
+      }
+    },
+    "graviton2": {
+      "from": ["aarch64"],
+      "vendor": "ARM",
+      "features": [
+          "fp",
+          "asimd",
+          "evtstrm",
+          "aes",
+          "pmull",
+          "sha1",
+          "sha2",
+          "crc32",
+          "atomics",
+          "fphp",
+          "asimdhp",
+          "cpuid",
+          "asimdrdm",
+          "lrcpc",
+          "dcpop",
+          "asimddp",
+          "ssbs"
+      ],
+      "compilers" : {
+          "gcc": [
+              {
+                  "versions": "4.8:4.8.9",
+                  "flags": "-march=armv8-a"
+              },
+              {
+                  "versions": "4.9:5.9",
+                  "flags": "-march=armv8-a+crc+crypto"
+              },
+              {
+                  "versions": "6:6.9",
+                  "flags" : "-march=armv8.1-a"
+              },
+              {
+                  "versions": "7:7.9",
+                  "flags" : "-march=armv8.2-a+fp16 -mtune=cortex-a72"
+              },
+              {
+                  "versions": "8.0:8.0",
+                  "flags" : "-march=armv8.2-a+fp16+dotprod+crypto -mtune=cortex-a72"
+              },
+              {
+                  "versions": "8.1:8.9",
+                  "flags" : "-march=armv8.2-a+fp16+rcpc+dotprod+crypto -mtune=cortex-a72"
+              },
+              {
+                  "versions": "9.0:",
+                  "flags" : "-march=armv8.2-a+fp16+rcpc+dotprod+crypto -mtune=neoverse-n1"
+              }
+          ],
+          "clang" : [
+              {
+                  "versions": "3.9:4.9",
+                  "flags" : "-march=armv8.2-a+fp16+crc+crypto"
+              },
+              {
+                  "versions": "5:",
+                  "flags" : "-march=armv8.2-a+fp16+rcpc+dotprod+crypto"
+              }
+          ]
+      }
+    },
     "arm": {
-      "from": null,
+      "from": [],
       "vendor": "generic",
       "features": [],
       "compilers": {
-        "clang": {
-          "versions": ":",
-          "family": "arm",
-          "flags": "-march={family} -mcpu=generic"
-        }
+        "clang": [
+          {
+            "versions": ":",
+            "family": "arm",
+            "flags": "-march={family} -mcpu=generic"
+          }
+        ]
       }
     },
     "ppc": {
-      "from": null,
+      "from": [],
       "vendor": "generic",
       "features": [],
       "compilers": {
       }
     },
     "ppcle": {
-      "from": null,
+      "from": [],
       "vendor": "generic",
       "features": [],
       "compilers": {
       }
     },
     "sparc": {
-      "from": null,
+      "from": [],
       "vendor": "generic",
       "features": [],
       "compilers": {
       }
     },
     "sparc64": {
-      "from": null,
+      "from": [],
       "vendor": "generic",
       "features": [],
       "compilers": {
diff --git a/lib/spack/external/archspec/json/cpu/microarchitectures_schema.json b/lib/spack/external/archspec/json/cpu/microarchitectures_schema.json
new file mode 100644
index 0000000000..c21a3a1b37
--- /dev/null
+++ b/lib/spack/external/archspec/json/cpu/microarchitectures_schema.json
@@ -0,0 +1,110 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "Schema for microarchitecture definitions and feature aliases",
+  "type": "object",
+  "additionalProperties": false,
+  "properties": {
+    "microarchitectures": {
+      "type": "object",
+      "patternProperties": {
+        "([\\w]*)": {
+          "type": "object",
+          "properties": {
+            "from": {
+              "$comment": "More than one parent",
+              "type": "array",
+              "items": {
+                "type": "string"
+              }
+            },
+            "vendor": {
+              "type": "string"
+            },
+            "features": {
+              "type": "array",
+              "items": {
+                "type": "string"
+              }
+            },
+            "compilers": {
+              "type": "object",
+              "patternProperties": {
+                "([\\w]*)": {
+                  "$comment": "Permit multiple entries since compilers change options across versions",
+                  "type": "array",
+                  "items": {
+                    "type": "object",
+                    "properties": {
+                      "versions": {
+                        "type": "string"
+                      },
+                      "name": {
+                        "type": "string"
+                      },
+                      "flags": {
+                        "type": "string"
+                      }
+                    },
+                    "required": [
+                      "versions",
+                      "flags"
+                    ]
+                  }
+                }
+              }
+            }
+          },
+          "required": [
+            "from",
+            "vendor",
+            "features"
+          ]
+        }
+      }
+    },
+    "feature_aliases": {
+      "type": "object",
+      "patternProperties": {
+        "([\\w]*)": {
+          "type": "object",
+          "properties": {
+            "reason": {
+              "$comment": "Comment containing the reason why an alias is there",
+              "type": "string"
+            },
+            "any_of": {
+              "$comment": "The alias is true if any of the items is a feature of the target",
+              "type": "array",
+              "items": {
+                "type": "string"
+              }
+            },
+            "families": {
+              "$comment": "The alias is true if the family of the target is in this list",
+              "type": "array",
+              "items": {
+                "type": "string"
+              }
+            }
+          },
+          "additionalProperties": false
+        }
+      }
+    },
+    "conversions": {
+      "type": "object",
+      "properties": {
+        "description": {
+          "type": "string"
+        },
+        "arm_vendors": {
+          "type": "object"
+        },
+        "darwin_flags": {
+          "type": "object"
+        }
+      },
+      "additionalProperties": false
+    }
+  }
+}
diff --git a/lib/spack/llnl/util/cpu/__init__.py b/lib/spack/llnl/util/cpu/__init__.py
deleted file mode 100644
index 5a4943c965..0000000000
--- a/lib/spack/llnl/util/cpu/__init__.py
+++ /dev/null
@@ -1,18 +0,0 @@
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
-# Spack Project Developers. See the top-level COPYRIGHT file for details.
-#
-# SPDX-License-Identifier: (Apache-2.0 OR MIT)
-
-from .microarchitecture import Microarchitecture, UnsupportedMicroarchitecture
-from .microarchitecture import targets, generic_microarchitecture
-from .microarchitecture import version_components
-from .detect import host
-
-__all__ = [
-    'Microarchitecture',
-    'UnsupportedMicroarchitecture',
-    'targets',
-    'generic_microarchitecture',
-    'host',
-    'version_components'
-]
diff --git a/lib/spack/llnl/util/cpu/alias.py b/lib/spack/llnl/util/cpu/alias.py
deleted file mode 100644
index abb4ea22f5..0000000000
--- a/lib/spack/llnl/util/cpu/alias.py
+++ /dev/null
@@ -1,102 +0,0 @@
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
-# Spack Project Developers. See the top-level COPYRIGHT file for details.
-#
-# SPDX-License-Identifier: (Apache-2.0 OR MIT)
-#: Known predicates that can be used to construct feature aliases
-
-from .schema import targets_json, LazyDictionary, properties
-
-_feature_alias_predicate = {}
-
-
-class FeatureAliasTest(object):
-    """A test that must be passed for a feature alias to succeed.
-
-    Args:
-        rules (dict): dictionary of rules to be met. Each key must be a
-            valid alias predicate
-    """
-    def __init__(self, rules):
-        self.rules = rules
-        self.predicates = []
-        for name, args in rules.items():
-            self.predicates.append(_feature_alias_predicate[name](args))
-
-    def __call__(self, microarchitecture):
-        return all(
-            feature_test(microarchitecture) for feature_test in self.predicates
-        )
-
-
-def _feature_aliases():
-    """Returns the dictionary of all defined feature aliases."""
-    json_data = targets_json['feature_aliases']
-    aliases = {}
-    for alias, rules in json_data.items():
-        aliases[alias] = FeatureAliasTest(rules)
-    return aliases
-
-
-feature_aliases = LazyDictionary(_feature_aliases)
-
-
-def alias_predicate(predicate_schema):
-    """Decorator to register a predicate that can be used to define
-    feature aliases.
-
-    Args:
-        predicate_schema (dict): schema to be enforced in
-            microarchitectures.json for the predicate
-    """
-    def decorator(func):
-        name = func.__name__
-
-        # Check we didn't register anything else with the same name
-        if name in _feature_alias_predicate:
-            msg = 'the alias predicate "{0}" already exists'.format(name)
-            raise KeyError(msg)
-
-        # Update the overall schema
-        alias_schema = properties['feature_aliases']['patternProperties']
-        alias_schema[r'([\w]*)']['properties'].update(
-            {name: predicate_schema}
-        )
-        # Register the predicate
-        _feature_alias_predicate[name] = func
-
-        return func
-    return decorator
-
-
-@alias_predicate(predicate_schema={'type': 'string'})
-def reason(motivation_for_the_alias):
-    """This predicate returns always True and it's there to allow writing
-    a documentation string in the JSON file to explain why an alias is needed.
-    """
-    return lambda x: True
-
-
-@alias_predicate(predicate_schema={
-    'type': 'array',
-    'items': {'type': 'string'}
-})
-def any_of(list_of_features):
-    """Returns a predicate that is True if any of the feature in the
-    list is in the microarchitecture being tested, False otherwise.
-    """
-    def _impl(microarchitecture):
-        return any(x in microarchitecture for x in list_of_features)
-    return _impl
-
-
-@alias_predicate(predicate_schema={
-    'type': 'array',
-    'items': {'type': 'string'}
-})
-def families(list_of_families):
-    """Returns a predicate that is True if the architecture family of
-    the microarchitecture being tested is in the list, False otherwise.
-    """
-    def _impl(microarchitecture):
-        return str(microarchitecture.family) in list_of_families
-    return _impl
diff --git a/lib/spack/llnl/util/cpu/schema.py b/lib/spack/llnl/util/cpu/schema.py
deleted file mode 100644
index 2cb456730e..0000000000
--- a/lib/spack/llnl/util/cpu/schema.py
+++ /dev/null
@@ -1,147 +0,0 @@
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
-# Spack Project Developers. See the top-level COPYRIGHT file for details.
-#
-# SPDX-License-Identifier: (Apache-2.0 OR MIT)
-import json
-import os.path
-
-try:
-    from collections.abc import MutableMapping  # novm
-except ImportError:
-    from collections import MutableMapping
-
-compilers_schema = {
-    'type': 'object',
-    'properties': {
-        'versions': {'type': 'string'},
-        'name': {'type': 'string'},
-        'flags': {'type': 'string'}
-    },
-    'required': ['versions', 'flags']
-}
-
-properties = {
-    'microarchitectures': {
-        'type': 'object',
-        'patternProperties': {
-            r'([\w]*)': {
-                'type': 'object',
-                'properties': {
-                    'from': {
-                        'anyOf': [
-                            # More than one parent
-                            {'type': 'array', 'items': {'type': 'string'}},
-                            # Exactly one parent
-                            {'type': 'string'},
-                            # No parent
-                            {'type': 'null'}
-                        ]
-                    },
-                    'vendor': {
-                        'type': 'string'
-                    },
-                    'features': {
-                        'type': 'array',
-                        'items': {'type': 'string'}
-                    },
-                    'compilers': {
-                        'type': 'object',
-                        'patternProperties': {
-                            r'([\w]*)': {
-                                'anyOf': [
-                                    compilers_schema,
-                                    {
-                                        'type': 'array',
-                                        'items': compilers_schema
-                                    }
-                                ]
-                            }
-                        }
-                    }
-                },
-                'required': ['from', 'vendor', 'features']
-            }
-        }
-    },
-    'feature_aliases': {
-        'type': 'object',
-        'patternProperties': {
-            r'([\w]*)': {
-                'type': 'object',
-                'properties': {},
-                'additionalProperties': False
-            }
-        },
-    },
-    'conversions': {
-        'type': 'object',
-        'properties': {
-            'description': {
-                'type': 'string'
-            },
-            'arm_vendors': {
-                'type': 'object',
-            },
-            'darwin_flags': {
-                'type': 'object'
-            }
-        },
-        'additionalProperties': False
-    }
-}
-
-schema = {
-    '$schema': 'http://json-schema.org/schema#',
-    'title': 'Schema for microarchitecture definitions and feature aliases',
-    'type': 'object',
-    'additionalProperties': False,
-    'properties': properties,
-}
-
-
-class LazyDictionary(MutableMapping):
-    """Lazy dictionary that gets constructed on first access to any object key
-
-    Args:
-        factory (callable): factory function to construct the dictionary
-    """
-
-    def __init__(self, factory, *args, **kwargs):
-        self.factory = factory
-        self.args = args
-        self.kwargs = kwargs
-        self._data = None
-
-    @property
-    def data(self):
-        if self._data is None:
-            self._data = self.factory(*self.args, **self.kwargs)
-        return self._data
-
-    def __getitem__(self, key):
-        return self.data[key]
-
-    def __setitem__(self, key, value):
-        self.data[key] = value
-
-    def __delitem__(self, key):
-        del self.data[key]
-
-    def __iter__(self):
-        return iter(self.data)
-
-    def __len__(self):
-        return len(self.data)
-
-
-def _load_targets_json():
-    """Loads ``microarchitectures.json`` in memory."""
-    directory_name = os.path.dirname(os.path.abspath(__file__))
-    filename = os.path.join(directory_name, 'microarchitectures.json')
-    with open(filename, 'r') as f:
-        return json.load(f)
-
-
-#: In memory representation of the data in microarchitectures.json,
-#: loaded on first access
-targets_json = LazyDictionary(_load_targets_json)
diff --git a/lib/spack/spack/architecture.py b/lib/spack/spack/architecture.py
index 15561d436c..ceb188064f 100644
--- a/lib/spack/spack/architecture.py
+++ b/lib/spack/spack/architecture.py
@@ -60,9 +60,9 @@ import functools
 import inspect
 import warnings
 
+import archspec.cpu
 import six
 
-import llnl.util.cpu as cpu
 import llnl.util.tty as tty
 from llnl.util.lang import memoized, list_modules, key_ordering
 
@@ -109,9 +109,9 @@ class Target(object):
                 current target. This is typically used on machines
                 like Cray (e.g. craype-compiler)
         """
-        if not isinstance(name, cpu.Microarchitecture):
-            name = cpu.targets.get(
-                name, cpu.generic_microarchitecture(name)
+        if not isinstance(name, archspec.cpu.Microarchitecture):
+            name = archspec.cpu.TARGETS.get(
+                name, archspec.cpu.generic_microarchitecture(name)
             )
         self.microarchitecture = name
         self.module_name = module_name
@@ -207,7 +207,9 @@ class Target(object):
         # has an unexpected suffix. If so, treat it as a compiler with a
         # custom spec.
         compiler_version = compiler.version
-        version_number, suffix = cpu.version_components(compiler.version)
+        version_number, suffix = archspec.cpu.version_components(
+            compiler.version
+        )
         if not version_number or suffix not in ('', 'apple'):
             # Try to deduce the underlying version of the compiler, regardless
             # of its name in compilers.yaml. Depending on where this function
@@ -555,7 +557,7 @@ def sys_type():
 def compatible_sys_types():
     """Returns a list of all the systypes compatible with the current host."""
     compatible_archs = []
-    current_host = cpu.host()
+    current_host = archspec.cpu.host()
     compatible_targets = [current_host] + current_host.ancestors
     for target in compatible_targets:
         arch = Arch(platform(), 'default_os', target)
diff --git a/lib/spack/spack/cmd/arch.py b/lib/spack/spack/cmd/arch.py
index 6f5dad758f..9751599b10 100644
--- a/lib/spack/spack/cmd/arch.py
+++ b/lib/spack/spack/cmd/arch.py
@@ -7,7 +7,7 @@ from __future__ import print_function
 
 import collections
 
-import llnl.util.cpu
+import archspec.cpu
 import llnl.util.tty.colify as colify
 import llnl.util.tty.color as color
 import spack.architecture as architecture
@@ -73,7 +73,7 @@ def display_targets(targets):
 
 def arch(parser, args):
     if args.known_targets:
-        display_targets(llnl.util.cpu.targets)
+        display_targets(archspec.cpu.TARGETS)
         return
 
     if args.frontend:
diff --git a/lib/spack/spack/compilers/__init__.py b/lib/spack/spack/compilers/__init__.py
index 452dc384a5..44a0f90371 100644
--- a/lib/spack/spack/compilers/__init__.py
+++ b/lib/spack/spack/compilers/__init__.py
@@ -15,7 +15,7 @@ import six
 import llnl.util.lang
 import llnl.util.filesystem as fs
 import llnl.util.tty as tty
-import llnl.util.cpu as cpu
+import archspec.cpu
 
 import spack.paths
 import spack.error
@@ -405,7 +405,7 @@ def get_compilers(config, cspec=None, arch_spec=None):
         target = items.get('target', None)
 
         try:
-            current_target = llnl.util.cpu.targets[str(arch_spec.target)]
+            current_target = archspec.cpu.TARGETS[str(arch_spec.target)]
             family = str(current_target.family)
         except KeyError:
             # TODO: Check if this exception handling makes sense, or if we
@@ -417,7 +417,7 @@ def get_compilers(config, cspec=None, arch_spec=None):
         if arch_spec and target and (target != family and target != 'any'):
             # If the family of the target is the family we are seeking,
             # there's an error in the underlying configuration
-            if llnl.util.cpu.targets[target].family == family:
+            if archspec.cpu.TARGETS[target].family == family:
                 msg = ('the "target" field in compilers.yaml accepts only '
                        'target families [replace "{0}" with "{1}"'
                        ' in "{2}" specification]')
@@ -664,7 +664,7 @@ def make_compiler_list(detected_versions):
         compiler_cls = spack.compilers.class_for_compiler_name(compiler_name)
         spec = spack.spec.CompilerSpec(compiler_cls.name, version)
         paths = [paths.get(x, None) for x in ('cc', 'cxx', 'f77', 'fc')]
-        target = cpu.host()
+        target = archspec.cpu.host()
         compiler = compiler_cls(
             spec, operating_system, str(target.family), paths
         )
diff --git a/lib/spack/spack/concretize.py b/lib/spack/spack/concretize.py
index eb09cce3a7..85c8022760 100644
--- a/lib/spack/spack/concretize.py
+++ b/lib/spack/spack/concretize.py
@@ -19,6 +19,9 @@ from __future__ import print_function
 import platform
 import os.path
 import tempfile
+
+import archspec.cpu
+
 import llnl.util.filesystem as fs
 import llnl.util.tty as tty
 
@@ -27,7 +30,6 @@ from functools_backport import reverse_order
 from contextlib import contextmanager
 
 import llnl.util.lang
-import llnl.util.cpu as cpu
 
 import spack.repo
 import spack.abi
@@ -325,7 +327,7 @@ class Concretizer(object):
         """
         target_prefs = PackagePrefs(spec.name, 'target')
         target_specs = [spack.spec.Spec('target=%s' % tname)
-                        for tname in cpu.targets]
+                        for tname in archspec.cpu.TARGETS]
 
         def tspec_filter(s):
             # Filter target specs by whether the architecture
@@ -333,7 +335,7 @@ class Concretizer(object):
             # we only consider x86_64 targets when on an
             # x86_64 machine, etc. This may need to change to
             # enable setting cross compiling as a default
-            target = cpu.targets[str(s.architecture.target)]
+            target = archspec.cpu.TARGETS[str(s.architecture.target)]
             arch_family_name = target.family.name
             return arch_family_name == platform.machine()
 
@@ -569,7 +571,7 @@ class Concretizer(object):
         Returns:
             True if any modification happened, False otherwise
         """
-        import llnl.util.cpu
+        import archspec.cpu
 
         # Try to adjust the target only if it is the default
         # target for this platform
@@ -589,14 +591,14 @@ class Concretizer(object):
 
         try:
             current_target.optimization_flags(spec.compiler)
-        except llnl.util.cpu.UnsupportedMicroarchitecture:
+        except archspec.cpu.UnsupportedMicroarchitecture:
             microarchitecture = current_target.microarchitecture
             for ancestor in microarchitecture.ancestors:
                 candidate = None
                 try:
                     candidate = spack.architecture.Target(ancestor)
                     candidate.optimization_flags(spec.compiler)
-                except llnl.util.cpu.UnsupportedMicroarchitecture:
+                except archspec.cpu.UnsupportedMicroarchitecture:
                     continue
 
                 if candidate is not None:
diff --git a/lib/spack/spack/main.py b/lib/spack/spack/main.py
index 3d60f5b4eb..f4265a5d68 100644
--- a/lib/spack/spack/main.py
+++ b/lib/spack/spack/main.py
@@ -21,7 +21,7 @@ import traceback
 import warnings
 from six import StringIO
 
-import llnl.util.cpu
+import archspec.cpu
 import llnl.util.filesystem as fs
 import llnl.util.tty as tty
 import llnl.util.tty.color as color
@@ -664,7 +664,7 @@ def print_setup_info(*info):
     # print environment module system if available. This can be expensive
     # on clusters, so skip it if not needed.
     if 'modules' in info:
-        generic_arch = llnl.util.cpu.host().family
+        generic_arch = archspec.cpu.host().family
         module_spec = 'environment-modules target={0}'.format(generic_arch)
         specs = spack.store.db.query(module_spec)
         if specs:
diff --git a/lib/spack/spack/platforms/cray.py b/lib/spack/spack/platforms/cray.py
index 684109f3e0..091f8d3ffb 100644
--- a/lib/spack/spack/platforms/cray.py
+++ b/lib/spack/spack/platforms/cray.py
@@ -2,12 +2,13 @@
 # Spack Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
-
 import os
 import os.path
 import re
 import platform
-import llnl.util.cpu as cpu
+
+import archspec.cpu
+
 import llnl.util.tty as tty
 from spack.paths import build_env_path
 from spack.util.executable import Executable
@@ -60,10 +61,12 @@ class Cray(Platform):
             raise NoPlatformError()
 
         # Setup frontend targets
-        for name in cpu.targets:
+        for name in archspec.cpu.TARGETS:
             if name not in self.targets:
                 self.add_target(name, Target(name))
-        self.front_end = os.environ.get('SPACK_FRONT_END', cpu.host().name)
+        self.front_end = os.environ.get(
+            'SPACK_FRONT_END', archspec.cpu.host().name
+        )
         if self.front_end not in self.targets:
             self.add_target(self.front_end, Target(self.front_end))
 
@@ -143,13 +146,13 @@ class Cray(Platform):
                 tty.debug("Found default module:%s" % default_from_module)
                 return default_from_module
             else:
-                front_end = cpu.host().name
+                front_end = archspec.cpu.host().name
                 if front_end in list(
                         map(lambda x: _target_name_from_craype_target_name(x),
                             self._avail_targets())
                 ):
                     tty.debug("default to front-end architecture")
-                    return cpu.host().name
+                    return archspec.cpu.host().name
                 else:
                     return platform.machine()
 
@@ -167,7 +170,8 @@ class Cray(Platform):
                 if 'craype-' in mod:
                     name = mod[7:]
                     _n = name.replace('-', '_')  # test for mic-knl/mic_knl
-                    is_target_name = name in cpu.targets or _n in cpu.targets
+                    is_target_name = (name in archspec.cpu.TARGETS or
+                                      _n in archspec.cpu.TARGETS)
                     is_cray_target_name = name in _craype_name_to_target_name
                     if is_target_name or is_cray_target_name:
                         targets.append(name)
diff --git a/lib/spack/spack/platforms/darwin.py b/lib/spack/spack/platforms/darwin.py
index 99a28cec9f..e36722723b 100644
--- a/lib/spack/spack/platforms/darwin.py
+++ b/lib/spack/spack/platforms/darwin.py
@@ -4,7 +4,9 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
 import platform
-import llnl.util.cpu as cpu
+
+import archspec.cpu
+
 from spack.architecture import Platform, Target
 from spack.operating_systems.mac_os import MacOs
 
@@ -17,10 +19,10 @@ class Darwin(Platform):
     def __init__(self):
         super(Darwin, self).__init__('darwin')
 
-        for name in cpu.targets:
+        for name in archspec.cpu.TARGETS:
             self.add_target(name, Target(name))
 
-        self.default = cpu.host().name
+        self.default = archspec.cpu.host().name
         self.front_end = self.default
         self.back_end = self.default
 
diff --git a/lib/spack/spack/platforms/linux.py b/lib/spack/spack/platforms/linux.py
index 4ffd7ad8e9..c7e1def2d9 100644
--- a/lib/spack/spack/platforms/linux.py
+++ b/lib/spack/spack/platforms/linux.py
@@ -2,11 +2,12 @@
 # Spack Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
-
 import platform
+
+import archspec.cpu
+
 from spack.architecture import Platform, Target
 from spack.operating_systems.linux_distro import LinuxDistro
-import llnl.util.cpu as cpu
 
 
 class Linux(Platform):
@@ -15,11 +16,11 @@ class Linux(Platform):
     def __init__(self):
         super(Linux, self).__init__('linux')
 
-        for name in cpu.targets:
+        for name in archspec.cpu.TARGETS:
             self.add_target(name, Target(name))
 
         # Get specific default
-        self.default = cpu.host().name
+        self.default = archspec.cpu.host().name
         self.front_end = self.default
         self.back_end = self.default
 
diff --git a/lib/spack/spack/test/concretize.py b/lib/spack/spack/test/concretize.py
index 65ac93105a..02305d84b5 100644
--- a/lib/spack/spack/test/concretize.py
+++ b/lib/spack/spack/test/concretize.py
@@ -2,8 +2,10 @@
 # Spack Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
-
 import pytest
+
+import archspec.cpu
+
 import llnl.util.lang
 
 import spack.architecture
@@ -92,13 +94,13 @@ def current_host(request, monkeypatch):
     # is_preference is not empty if we want to supply the
     # preferred target via packages.yaml
     cpu, _, is_preference = request.param.partition('-')
-    target = llnl.util.cpu.targets[cpu]
+    target = archspec.cpu.TARGETS[cpu]
 
     # this function is memoized, so clear its state for testing
     spack.architecture.get_platform.cache.clear()
 
     if not is_preference:
-        monkeypatch.setattr(llnl.util.cpu, 'host', lambda: target)
+        monkeypatch.setattr(archspec.cpu, 'host', lambda: target)
         monkeypatch.setattr(spack.platforms.test.Test, 'default', cpu)
         yield target
     else:
@@ -613,14 +615,13 @@ class TestConcretize(object):
         ('mpileaks%gcc@4.4.7', 'core2'),
         ('mpileaks%gcc@4.8', 'haswell'),
         ('mpileaks%gcc@5.3.0', 'broadwell'),
-        # Apple's clang always falls back to x86-64 for now
-        ('mpileaks%apple-clang@9.1.0', 'x86_64')
+        ('mpileaks%apple-clang@5.1.0', 'x86_64')
     ])
     @pytest.mark.regression('13361')
     def test_adjusting_default_target_based_on_compiler(
             self, spec, best_achievable, current_host
     ):
-        best_achievable = llnl.util.cpu.targets[best_achievable]
+        best_achievable = archspec.cpu.TARGETS[best_achievable]
         expected = best_achievable if best_achievable < current_host \
             else current_host
         with spack.concretize.disable_compiler_existence_check():
diff --git a/lib/spack/spack/test/data/targets/darwin-mojave-haswell b/lib/spack/spack/test/data/targets/darwin-mojave-haswell
deleted file mode 100644
index 45054c5676..0000000000
--- a/lib/spack/spack/test/data/targets/darwin-mojave-haswell
+++ /dev/null
@@ -1,5 +0,0 @@
-machdep.cpu.vendor: GenuineIntel
-machdep.cpu.model: 70
-machdep.cpu.brand_string: Intel(R) Core(TM) i7-4980HQ CPU @ 2.80GHz
-machdep.cpu.features: FPU VME DE PSE TSC MSR PAE MCE CX8 APIC SEP MTRR PGE MCA CMOV PAT PSE36 CLFSH DS ACPI MMX FXSR SSE SSE2 SS HTT TM PBE SSE3 PCLMULQDQ DTES64 MON DSCPL VMX SMX EST TM2 SSSE3 FMA CX16 TPR PDCM SSE4.1 SSE4.2 x2APIC MOVBE POPCNT AES PCID XSAVE OSXSAVE SEGLIM64 TSCTMR AVX1.0 RDRAND F16C
-machdep.cpu.leaf7_features: RDWRFSGS TSC_THREAD_OFFSET BMI1 AVX2 SMEP BMI2 ERMS INVPCID FPU_CSDS MDCLEAR IBRS STIBP L1DF SSBD
diff --git a/lib/spack/spack/test/data/targets/darwin-mojave-ivybridge b/lib/spack/spack/test/data/targets/darwin-mojave-ivybridge
deleted file mode 100644
index 6a52d6c19d..0000000000
--- a/lib/spack/spack/test/data/targets/darwin-mojave-ivybridge
+++ /dev/null
@@ -1,59 +0,0 @@
-machdep.cpu.max_basic: 13
-machdep.cpu.max_ext: 2147483656
-machdep.cpu.vendor: GenuineIntel
-machdep.cpu.brand_string: Intel(R) Core(TM) i5-3230M CPU @ 2.60GHz
-machdep.cpu.family: 6
-machdep.cpu.model: 58
-machdep.cpu.extmodel: 3
-machdep.cpu.extfamily: 0
-machdep.cpu.stepping: 9
-machdep.cpu.feature_bits: 9203919201183202303
-machdep.cpu.leaf7_feature_bits: 641 0
-machdep.cpu.leaf7_feature_bits_edx: 2617246720
-machdep.cpu.extfeature_bits: 4967106816
-machdep.cpu.signature: 198313
-machdep.cpu.brand: 0
-machdep.cpu.features: FPU VME DE PSE TSC MSR PAE MCE CX8 APIC SEP MTRR PGE MCA CMOV PAT PSE36 CLFSH DS ACPI MMX FXSR SSE SSE2 SS HTT TM PBE SSE3 PCLMULQDQ DTES64 MON DSCPL VMX EST TM2 SSSE3 CX16 TPR PDCM SSE4.1 SSE4.2 x2APIC POPCNT AES PCID XSAVE OSXSAVE TSCTMR AVX1.0 RDRAND F16C
-machdep.cpu.leaf7_features: RDWRFSGS SMEP ERMS MDCLEAR IBRS STIBP L1DF SSBD
-machdep.cpu.extfeatures: SYSCALL XD EM64T LAHF RDTSCP TSCI
-machdep.cpu.logical_per_package: 16
-machdep.cpu.cores_per_package: 8
-machdep.cpu.microcode_version: 33
-machdep.cpu.processor_flag: 4
-machdep.cpu.mwait.linesize_min: 64
-machdep.cpu.mwait.linesize_max: 64
-machdep.cpu.mwait.extensions: 3
-machdep.cpu.mwait.sub_Cstates: 135456
-machdep.cpu.thermal.sensor: 1
-machdep.cpu.thermal.dynamic_acceleration: 1
-machdep.cpu.thermal.invariant_APIC_timer: 1
-machdep.cpu.thermal.thresholds: 2
-machdep.cpu.thermal.ACNT_MCNT: 1
-machdep.cpu.thermal.core_power_limits: 1
-machdep.cpu.thermal.fine_grain_clock_mod: 1
-machdep.cpu.thermal.package_thermal_intr: 1
-machdep.cpu.thermal.hardware_feedback: 0
-machdep.cpu.thermal.energy_policy: 0
-machdep.cpu.xsave.extended_state: 7 832 832 0
-machdep.cpu.xsave.extended_state1: 1 0 0 0
-machdep.cpu.arch_perf.version: 3
-machdep.cpu.arch_perf.number: 4
-machdep.cpu.arch_perf.width: 48
-machdep.cpu.arch_perf.events_number: 7
-machdep.cpu.arch_perf.events: 0
-machdep.cpu.arch_perf.fixed_number: 3
-machdep.cpu.arch_perf.fixed_width: 48
-machdep.cpu.cache.linesize: 64
-machdep.cpu.cache.L2_associativity: 8
-machdep.cpu.cache.size: 256
-machdep.cpu.tlb.inst.small: 64
-machdep.cpu.tlb.inst.large: 8
-machdep.cpu.tlb.data.small: 64
-machdep.cpu.tlb.data.large: 32
-machdep.cpu.tlb.shared: 512
-machdep.cpu.address_bits.physical: 36
-machdep.cpu.address_bits.virtual: 48
-machdep.cpu.core_count: 2
-machdep.cpu.thread_count: 4
-machdep.cpu.tsc_ccc.numerator: 0
-machdep.cpu.tsc_ccc.denominator: 0
diff --git a/lib/spack/spack/test/data/targets/darwin-mojave-skylake b/lib/spack/spack/test/data/targets/darwin-mojave-skylake
deleted file mode 100644
index 67dc28a966..0000000000
--- a/lib/spack/spack/test/data/targets/darwin-mojave-skylake
+++ /dev/null
@@ -1,5 +0,0 @@
-machdep.cpu.vendor: GenuineIntel
-machdep.cpu.features: FPU VME DE PSE TSC MSR PAE MCE CX8 APIC SEP MTRR PGE MCA CMOV PAT PSE36 CLFSH DS ACPI MMX FXSR SSE SSE2 SS HTT TM PBE SSE3 PCLMULQDQ DTES64 MON DSCPL VMX EST TM2 SSSE3 FMA CX16 TPR PDCM SSE4.1 SSE4.2 x2APIC MOVBE POPCNT AES PCID XSAVE OSXSAVE SEGLIM64 TSCTMR AVX1.0 RDRAND F16C
-machdep.cpu.leaf7_features: RDWRFSGS TSC_THREAD_OFFSET SGX BMI1 HLE AVX2 SMEP BMI2 ERMS INVPCID RTM FPU_CSDS MPX RDSEED ADX SMAP CLFSOPT IPT MDCLEAR TSXFA IBRS STIBP L1DF SSBD
-machdep.cpu.model: 94
-machdep.cpu.brand_string: Intel(R) Core(TM) i7-6700K CPU @ 4.00GHz
diff --git a/lib/spack/spack/test/data/targets/linux-centos7-cascadelake b/lib/spack/spack/test/data/targets/linux-centos7-cascadelake
deleted file mode 100644
index e409c3d07a..0000000000
--- a/lib/spack/spack/test/data/targets/linux-centos7-cascadelake
+++ /dev/null
@@ -1,20 +0,0 @@
-processor       : 0
-vendor_id       : GenuineIntel
-cpu family      : 6
-model           : 85
-model name      : Intel(R) Xeon(R) Platinum 8260M CPU @ 2.40GHz
-stepping        : 7
-microcode       : 0x5000024
-cpu MHz         : 2400.000
-cache size      : 36608 KB
-physical id     : 0
-siblings        : 48
-core id         : 0
-cpu cores       : 24
-apicid          : 0
-initial apicid  : 0
-fpu             : yes
-fpu_exception   : yes
-cpuid level     : 22
-wp              : yes
-flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch epb cat_l3 cdp_l3 intel_ppin intel_pt ssbd mba ibrs ibpb stibp ibrs_enhanced tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm mpx rdt_a avx512f avx512dq rdseed adx smap clflushopt clwb avx512cd avx512bw avx512vl xsaveopt xsavec xgetbv1 cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local dtherm ida arat pln pts hwp hwp_act_window hwp_epp hwp_pkg_req pku ospke avx512_vnni md_clear spec_ctrl intel_stibp flush_l1d arch_capabilities
\ No newline at end of file
diff --git a/lib/spack/spack/test/data/targets/linux-centos7-power8le b/lib/spack/spack/test/data/targets/linux-centos7-power8le
deleted file mode 100644
index f21ca85323..0000000000
--- a/lib/spack/spack/test/data/targets/linux-centos7-power8le
+++ /dev/null
@@ -1,4 +0,0 @@
-processor	: 0
-cpu		: POWER8NVL (raw), altivec supported
-clock		: 2061.000000MHz
-revision	: 1.0 (pvr 004c 0100)
diff --git a/lib/spack/spack/test/data/targets/linux-centos7-thunderx2 b/lib/spack/spack/test/data/targets/linux-centos7-thunderx2
deleted file mode 100644
index 2447306bac..0000000000
--- a/lib/spack/spack/test/data/targets/linux-centos7-thunderx2
+++ /dev/null
@@ -1,8 +0,0 @@
-processor       : 0
-BogoMIPS        : 400.00
-Features        : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics cpuid asimdrdm
-CPU implementer : 0x43
-CPU architecture: 8
-CPU variant     : 0x1
-CPU part        : 0x0af
-CPU revision    : 1
diff --git a/lib/spack/spack/test/data/targets/linux-fedora32-icelake b/lib/spack/spack/test/data/targets/linux-fedora32-icelake
deleted file mode 100644
index 2dcf1b9c5b..0000000000
--- a/lib/spack/spack/test/data/targets/linux-fedora32-icelake
+++ /dev/null
@@ -1,27 +0,0 @@
-processor	: 0
-vendor_id	: GenuineIntel
-cpu family	: 6
-model		: 126
-model name	: Intel(R) Core(TM) i7-1065G7 CPU @ 1.30GHz
-stepping	: 5
-microcode	: 0x78
-cpu MHz		: 1091.701
-cache size	: 8192 KB
-physical id	: 0
-siblings	: 8
-core id		: 0
-cpu cores	: 4
-apicid		: 0
-initial apicid	: 0
-fpu		: yes
-fpu_exception	: yes
-cpuid level	: 27
-wp		: yes
-flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb invpcid_single ssbd ibrs ibpb stibp ibrs_enhanced tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid avx512f avx512dq rdseed adx smap avx512ifma clflushopt intel_pt avx512cd sha_ni avx512bw avx512vl xsaveopt xsavec xgetbv1 xsaves split_lock_detect dtherm ida arat pln pts hwp hwp_act_window hwp_epp hwp_pkg_req avx512vbmi umip pku ospke avx512_vbmi2 gfni vaes vpclmulqdq avx512_vnni avx512_bitalg avx512_vpopcntdq rdpid fsrm md_clear flush_l1d arch_capabilities
-vmx flags	: vnmi preemption_timer posted_intr invvpid ept_x_only ept_ad ept_1gb flexpriority apicv tsc_offset vtpr mtf vapic ept vpid unrestricted_guest vapic_reg vid ple pml ept_mode_based_exec tsc_scaling
-bugs		: spectre_v1 spectre_v2 spec_store_bypass swapgs itlb_multihit
-bogomips	: 2995.20
-clflush size	: 64
-cache_alignment	: 64
-address sizes	: 39 bits physical, 48 bits virtual
-power management:
diff --git a/lib/spack/spack/test/data/targets/linux-rhel6-piledriver b/lib/spack/spack/test/data/targets/linux-rhel6-piledriver
deleted file mode 100644
index 599d0c6fe7..0000000000
--- a/lib/spack/spack/test/data/targets/linux-rhel6-piledriver
+++ /dev/null
@@ -1,29 +0,0 @@
-processor       : 0
-vendor_id       : AuthenticAMD
-cpu family      : 21
-model           : 2
-model name      : AMD FX(tm)-8350 Eight-Core Processor
-stepping        : 0
-microcode       : 0x6000832
-cpu MHz         : 4013.832
-cache size      : 2048 KB
-physical id     : 0
-siblings        : 8
-core id         : 0
-cpu cores       : 4
-apicid          : 16
-initial apicid  : 0
-fpu             : yes
-fpu_exception   : yes
-cpuid level     : 13
-wp              : yes
-flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt lwp fma4 tce nodeid_msr tbm topoext perfctr_core perfctr_nb arat cpb hw_pstate npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold vmmcall bmi1
-bugs            : fxsave_leak sysret_ss_attrs
-bogomips        : 8030.15
-TLB size        : 1536 4K pages
-clflush size    : 64
-cache_alignment : 64
-address sizes   : 48 bits physical, 48 bits virtual
-power management: ts ttp tm 100mhzsteps hwpstate cpb eff_freq_ro
-
-# /proc/cpuinfo taken from https://www.redhat.com/archives/vfio-users/2015-August/msg00111.html
\ No newline at end of file
diff --git a/lib/spack/spack/test/data/targets/linux-rhel7-broadwell b/lib/spack/spack/test/data/targets/linux-rhel7-broadwell
deleted file mode 100644
index 427cd85bf2..0000000000
--- a/lib/spack/spack/test/data/targets/linux-rhel7-broadwell
+++ /dev/null
@@ -1,25 +0,0 @@
-processor	: 0
-vendor_id	: GenuineIntel
-cpu family	: 6
-model		: 79
-model name	: Intel(R) Xeon(R) CPU E5-2690 v4 @ 2.60GHz
-stepping	: 1
-microcode	: 0xb00002a
-cpu MHz		: 2600.000
-cache size	: 35840 KB
-physical id	: 0
-siblings	: 14
-core id		: 0
-cpu cores	: 14
-apicid		: 0
-initial apicid	: 0
-fpu		: yes
-fpu_exception	: yes
-cpuid level	: 20
-wp		: yes
-flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 ds_cpl vmx smx est tm2 ssse3 fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch epb cat_l3 cdp_l3 invpcid_single intel_pt tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm rdt_a rdseed adx smap xsaveopt cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local ibpb ibrs stibp dtherm arat pln pts spec_ctrl intel_stibp
-bogomips	: 5188.06
-clflush size	: 64
-cache_alignment	: 64
-address sizes	: 46 bits physical, 48 bits virtual
-power management:
diff --git a/lib/spack/spack/test/data/targets/linux-rhel7-haswell b/lib/spack/spack/test/data/targets/linux-rhel7-haswell
deleted file mode 100644
index 7bb5aa958f..0000000000
--- a/lib/spack/spack/test/data/targets/linux-rhel7-haswell
+++ /dev/null
@@ -1,25 +0,0 @@
-processor	: 0
-vendor_id	: GenuineIntel
-cpu family	: 6
-model		: 63
-model name	: Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz
-stepping	: 2
-microcode	: 0x3c
-cpu MHz		: 1757.910
-cache size	: 30720 KB
-physical id	: 0
-siblings	: 12
-core id		: 0
-cpu cores	: 12
-apicid		: 0
-initial apicid	: 0
-fpu		: yes
-fpu_exception	: yes
-cpuid level	: 15
-wp		: yes
-flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm epb invpcid_single tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid cqm xsaveopt cqm_llc cqm_occup_llc ibpb ibrs stibp dtherm arat pln pts spec_ctrl intel_stibp
-bogomips	: 4987.97
-clflush size	: 64
-cache_alignment	: 64
-address sizes	: 46 bits physical, 48 bits virtual
-power management:
diff --git a/lib/spack/spack/test/data/targets/linux-rhel7-ivybridge b/lib/spack/spack/test/data/targets/linux-rhel7-ivybridge
deleted file mode 100644
index 7d6cfe4daa..0000000000
--- a/lib/spack/spack/test/data/targets/linux-rhel7-ivybridge
+++ /dev/null
@@ -1,25 +0,0 @@
-processor	: 0
-vendor_id	: GenuineIntel
-cpu family	: 6
-model		: 62
-model name	: Intel(R) Xeon(R) CPU E5-2650 v2 @ 2.60GHz
-stepping	: 4
-microcode	: 0x42c
-cpu MHz		: 1862.554
-cache size	: 20480 KB
-physical id	: 0
-siblings	: 8
-core id		: 0
-cpu cores	: 8
-apicid		: 0
-initial apicid	: 0
-fpu		: yes
-fpu_exception	: yes
-cpuid level	: 13
-wp		: yes
-flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm epb tpr_shadow vnmi flexpriority ept vpid fsgsbase smep erms xsaveopt ibpb ibrs stibp dtherm ida arat pln pts spec_ctrl intel_stibp
-bogomips	: 5200.15
-clflush size	: 64
-cache_alignment	: 64
-address sizes	: 46 bits physical, 48 bits virtual
-power management:
diff --git a/lib/spack/spack/test/data/targets/linux-rhel7-skylake_avx512 b/lib/spack/spack/test/data/targets/linux-rhel7-skylake_avx512
deleted file mode 100644
index e9ab1987dd..0000000000
--- a/lib/spack/spack/test/data/targets/linux-rhel7-skylake_avx512
+++ /dev/null
@@ -1,25 +0,0 @@
-processor	: 0
-vendor_id	: GenuineIntel
-cpu family	: 6
-model		: 85
-model name	: Intel(R) Xeon(R) Gold 6132 CPU @ 2.60GHz
-stepping	: 4
-microcode	: 0x200004d
-cpu MHz		: 2600.000
-cache size	: 19712 KB
-physical id	: 0
-siblings	: 14
-core id		: 0
-cpu cores	: 14
-apicid		: 0
-initial apicid	: 0
-fpu		: yes
-fpu_exception	: yes
-cpuid level	: 22
-wp		: yes
-flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch epb cat_l3 cdp_l3 invpcid_single intel_pt tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm mpx rdt_a avx512f avx512dq rdseed adx smap clflushopt clwb avx512cd avx512bw avx512vl xsaveopt xsavec xgetbv1 cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local ibpb ibrs stibp dtherm ida arat pln pts spec_ctrl intel_stibp ssbd
-bogomips	: 5200.00
-clflush size	: 64
-cache_alignment	: 64
-address sizes	: 46 bits physical, 48 bits virtual
-power management:
diff --git a/lib/spack/spack/test/data/targets/linux-rhel7-zen b/lib/spack/spack/test/data/targets/linux-rhel7-zen
deleted file mode 100644
index 014dec3359..0000000000
--- a/lib/spack/spack/test/data/targets/linux-rhel7-zen
+++ /dev/null
@@ -1,26 +0,0 @@
-processor	: 0
-vendor_id	: AuthenticAMD
-cpu family	: 23
-model		: 1
-model name	: AMD EPYC 7301 16-Core Processor
-stepping	: 2
-microcode	: 0x8001227
-cpu MHz		: 2200.000
-cache size	: 512 KB
-physical id	: 0
-siblings	: 32
-core id		: 0
-cpu cores	: 16
-apicid		: 0
-initial apicid	: 0
-fpu		: yes
-fpu_exception	: yes
-cpuid level	: 13
-wp		: yes
-flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc art rep_good nopl nonstop_tsc extd_apicid amd_dcm aperfmperf eagerfpu pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c rdrand lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw skinit wdt tce topoext perfctr_core perfctr_nb bpext perfctr_l2 cpb hw_pstate retpoline_amd ssbd ibpb vmmcall fsgsbase bmi1 avx2 smep bmi2 rdseed adx smap clflushopt sha_ni xsaveopt xsavec xgetbv1 clzero irperf xsaveerptr arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold avic v_vmsave_vmload vgif overflow_recov succor smca
-bogomips	: 4399.40
-TLB size	: 2560 4K pages
-clflush size	: 64
-cache_alignment	: 64
-address sizes	: 48 bits physical, 48 bits virtual
-power management: ts ttp tm hwpstate cpb eff_freq_ro [13] [14]
diff --git a/lib/spack/spack/test/data/targets/linux-scientific7-k10 b/lib/spack/spack/test/data/targets/linux-scientific7-k10
deleted file mode 100644
index 1522b17480..0000000000
--- a/lib/spack/spack/test/data/targets/linux-scientific7-k10
+++ /dev/null
@@ -1,26 +0,0 @@
-processor       : 0
-vendor_id       : AuthenticAMD
-cpu family      : 16
-model           : 9
-model name      : AMD Opteron(tm) Processor 6136
-stepping        : 1
-microcode       : 0x10000d9
-cpu MHz         : 800.000
-cache size      : 512 KB
-physical id     : 0
-siblings        : 8
-core id         : 0
-cpu cores       : 8
-apicid          : 16
-initial apicid  : 0
-fpu             : yes
-fpu_exception   : yes
-cpuid level     : 5
-wp              : yes
-flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc art rep_good nopl nonstop_tsc extd_apicid amd_dcm pni monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt nodeid_msr hw_pstate retpoline_amd ibp_disable vmmcall npt lbrv svm_lock nrip_save pausefilter
-bogomips        : 4800.19
-TLB size        : 1024 4K pages
-clflush size    : 64
-cache_alignment : 64
-address sizes   : 48 bits physical, 48 bits virtual
-power management: ts ttp tm stc 100mhzsteps hwpstate
diff --git a/lib/spack/spack/test/data/targets/linux-scientific7-piledriver b/lib/spack/spack/test/data/targets/linux-scientific7-piledriver
deleted file mode 100644
index 4c823f6e46..0000000000
--- a/lib/spack/spack/test/data/targets/linux-scientific7-piledriver
+++ /dev/null
@@ -1,26 +0,0 @@
-processor	: 0
-vendor_id	: AuthenticAMD
-cpu family	: 21
-model		: 2
-model name	: AMD Opteron(tm) Processor 6320
-stepping	: 0
-microcode	: 0x6000852
-cpu MHz		: 1400.000
-cache size	: 2048 KB
-physical id	: 0
-siblings	: 8
-core id		: 0
-cpu cores	: 4
-apicid		: 32
-initial apicid	: 0
-fpu		: yes
-fpu_exception	: yes
-cpuid level	: 13
-wp		: yes
-flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc art rep_good nopl nonstop_tsc extd_apicid amd_dcm aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt fma4 tce nodeid_msr tbm topoext perfctr_core perfctr_nb cpb hw_pstate retpoline_amd ssbd ibpb vmmcall bmi1 arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold
-bogomips	: 5600.11
-TLB size	: 1536 4K pages
-clflush size	: 64
-cache_alignment	: 64
-address sizes	: 48 bits physical, 48 bits virtual
-power management: ts ttp tm 100mhzsteps hwpstate cpb eff_freq_ro
diff --git a/lib/spack/spack/test/data/targets/linux-scientificfermi6-bulldozer b/lib/spack/spack/test/data/targets/linux-scientificfermi6-bulldozer
deleted file mode 100644
index c240cfc6ce..0000000000
--- a/lib/spack/spack/test/data/targets/linux-scientificfermi6-bulldozer
+++ /dev/null
@@ -1,25 +0,0 @@
-processor       : 0
-vendor_id       : AuthenticAMD
-cpu family      : 21
-model           : 1
-model name      : AMD Opteron(TM) Processor 6212
-stepping        : 2
-cpu MHz         : 2600.188
-cache size      : 2048 KB
-physical id     : 0
-siblings        : 8
-core id         : 0
-cpu cores       : 4
-apicid          : 32
-initial apicid  : 0
-fpu             : yes
-fpu_exception   : yes
-cpuid level     : 13
-wp              : yes
-flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nonstop_tsc extd_apicid amd_dcm aperfmperf pni pclmulqdq monitor ssse3 cx16 sse4_1 sse4_2 popcnt aes xsave avx lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt lwp fma4 nodeid_msr topoext perfctr_core perfctr_nb cpb ssbd retpoline ibpb npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold
-bogomips        : 5200.37
-TLB size        : 1536 4K pages
-clflush size    : 64
-cache_alignment : 64
-address sizes   : 48 bits physical, 48 bits virtual
-power management: ts ttp tm 100mhzsteps hwpstate cpb
diff --git a/lib/spack/spack/test/data/targets/linux-scientificfermi6-piledriver b/lib/spack/spack/test/data/targets/linux-scientificfermi6-piledriver
deleted file mode 100644
index a87afeee61..0000000000
--- a/lib/spack/spack/test/data/targets/linux-scientificfermi6-piledriver
+++ /dev/null
@@ -1,25 +0,0 @@
-processor	: 31
-vendor_id	: AuthenticAMD
-cpu family	: 21
-model		: 2
-model name	: AMD Opteron(tm) Processor 6320
-stepping	: 0
-cpu MHz		: 2800.154
-cache size	: 2048 KB
-physical id	: 3
-siblings	: 8
-core id		: 3
-cpu cores	: 4
-apicid		: 135
-initial apicid	: 103
-fpu		: yes
-fpu_exception	: yes
-cpuid level	: 13
-wp		: yes
-flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nonstop_tsc extd_apicid amd_dcm aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt lwp fma4 tce nodeid_msr tbm topoext perfctr_core perfctr_nb cpb ssbd retpoline ibpb npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold bmi1
-bogomips	: 5599.22
-TLB size	: 1536 4K pages
-clflush size	: 64
-cache_alignment	: 64
-address sizes	: 48 bits physical, 48 bits virtual
-power management: ts ttp tm 100mhzsteps hwpstate cpb eff_freq_ro
diff --git a/lib/spack/spack/test/data/targets/linux-ubuntu18.04-broadwell b/lib/spack/spack/test/data/targets/linux-ubuntu18.04-broadwell
deleted file mode 100644
index bbe287ebf1..0000000000
--- a/lib/spack/spack/test/data/targets/linux-ubuntu18.04-broadwell
+++ /dev/null
@@ -1,26 +0,0 @@
-processor	: 0
-vendor_id	: GenuineIntel
-cpu family	: 6
-model		: 61
-model name	: Intel(R) Core(TM) i5-5200U CPU @ 2.20GHz
-stepping	: 4
-microcode	: 0x2d
-cpu MHz		: 1944.124
-cache size	: 3072 KB
-physical id	: 0
-siblings	: 4
-core id		: 0
-cpu cores	: 2
-apicid		: 0
-initial apicid	: 0
-fpu		: yes
-fpu_exception	: yes
-cpuid level	: 20
-wp		: yes
-flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb invpcid_single pti ssbd ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid rdseed adx smap intel_pt xsaveopt dtherm ida arat pln pts md_clear flush_l1d
-bugs		: cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds
-bogomips	: 4389.80
-clflush size	: 64
-cache_alignment	: 64
-address sizes	: 39 bits physical, 48 bits virtual
-power management:
diff --git a/lib/spack/spack/test/llnl/util/cpu.py b/lib/spack/spack/test/llnl/util/cpu.py
deleted file mode 100644
index f1d5ac06de..0000000000
--- a/lib/spack/spack/test/llnl/util/cpu.py
+++ /dev/null
@@ -1,293 +0,0 @@
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
-# Spack Project Developers. See the top-level COPYRIGHT file for details.
-#
-# SPDX-License-Identifier: (Apache-2.0 OR MIT)
-
-import pytest
-
-import contextlib
-import os.path
-
-import jsonschema
-
-import llnl.util.cpu
-import llnl.util.cpu.detect
-
-import spack.paths
-
-# This is needed to check that with repr we could create equivalent objects
-from llnl.util.cpu import Microarchitecture  # noqa
-
-
-@pytest.fixture(params=[
-    'linux-ubuntu18.04-broadwell',
-    'linux-rhel7-broadwell',
-    'linux-rhel7-skylake_avx512',
-    'linux-rhel7-ivybridge',
-    'linux-rhel7-haswell',
-    'linux-rhel7-zen',
-    'linux-scientific7-k10',
-    'linux-scientificfermi6-bulldozer',
-    'linux-scientificfermi6-piledriver',
-    'linux-scientific7-piledriver',
-    'linux-rhel6-piledriver',
-    'linux-centos7-power8le',
-    'linux-centos7-thunderx2',
-    'linux-centos7-cascadelake',
-    'linux-fedora32-icelake',
-    'darwin-mojave-ivybridge',
-    'darwin-mojave-haswell',
-    'darwin-mojave-skylake',
-])
-def expected_target(request, monkeypatch):
-    cpu = llnl.util.cpu
-    platform, operating_system, target = request.param.split('-')
-
-    architecture_family = llnl.util.cpu.targets[target].family
-    monkeypatch.setattr(
-        cpu.detect.platform, 'machine', lambda: str(architecture_family)
-    )
-
-    # Monkeypatch for linux
-    if platform == 'linux':
-        monkeypatch.setattr(cpu.detect.platform, 'system', lambda: 'Linux')
-
-        @contextlib.contextmanager
-        def _open(not_used_arg):
-            filename = os.path.join(
-                spack.paths.test_path, 'data', 'targets', request.param
-            )
-            with open(filename) as f:
-                yield f
-
-        monkeypatch.setattr(cpu.detect, 'open', _open, raising=False)
-
-    elif platform == 'darwin':
-        monkeypatch.setattr(cpu.detect.platform, 'system', lambda: 'Darwin')
-
-        filename = os.path.join(
-            spack.paths.test_path, 'data', 'targets', request.param
-        )
-        info = {}
-        with open(filename) as f:
-            for line in f:
-                key, value = line.split(':')
-                info[key.strip()] = value.strip()
-
-        def _check_output(args, env):
-            current_key = args[-1]
-            return info[current_key]
-
-        monkeypatch.setattr(cpu.detect, 'check_output', _check_output)
-
-    return llnl.util.cpu.targets[target]
-
-
-@pytest.fixture(params=[x for x in llnl.util.cpu.targets])
-def supported_target(request):
-    return request.param
-
-
-@pytest.mark.regression('13803')
-def test_target_detection(expected_target):
-    detected_target = llnl.util.cpu.host()
-    assert detected_target == expected_target
-
-
-def test_no_dashes_in_target_names(supported_target):
-    assert '-' not in supported_target
-
-
-def test_str_conversion(supported_target):
-    assert supported_target == str(llnl.util.cpu.targets[supported_target])
-
-
-def test_repr_conversion(supported_target):
-    target = llnl.util.cpu.targets[supported_target]
-    assert eval(repr(target)) == target
-
-
-def test_equality(supported_target):
-    target = llnl.util.cpu.targets[supported_target]
-
-    for name, other_target in llnl.util.cpu.targets.items():
-        if name == supported_target:
-            assert other_target == target
-        else:
-            assert other_target != target
-
-
-@pytest.mark.parametrize('operation,expected_result', [
-    # Test microarchitectures that are ordered with respect to each other
-    ('x86_64 < skylake', True),
-    ('icelake > skylake', True),
-    ('piledriver <= steamroller', True),
-    ('zen2 >= zen', True),
-    ('zen >= zen', True),
-    ('aarch64 <= thunderx2', True),
-    ('aarch64 <= a64fx', True),
-    # Test unrelated microarchitectures
-    ('power8 < skylake', False),
-    ('power8 <= skylake', False),
-    ('skylake < power8', False),
-    ('skylake <= power8', False),
-    # Test microarchitectures of the same family that are not a "subset"
-    # of each other
-    ('cascadelake > cannonlake', False),
-    ('cascadelake < cannonlake', False),
-    ('cascadelake <= cannonlake', False),
-    ('cascadelake >= cannonlake', False),
-    ('cascadelake == cannonlake', False),
-    ('cascadelake != cannonlake', True)
-])
-def test_partial_ordering(operation, expected_result):
-    target, operator, other_target = operation.split()
-    target = llnl.util.cpu.targets[target]
-    other_target = llnl.util.cpu.targets[other_target]
-    code = 'target ' + operator + 'other_target'
-    assert eval(code) is expected_result
-
-
-@pytest.mark.parametrize('target_name,expected_family', [
-    ('skylake', 'x86_64'),
-    ('zen', 'x86_64'),
-    ('pentium2', 'x86'),
-])
-def test_architecture_family(target_name, expected_family):
-    target = llnl.util.cpu.targets[target_name]
-    assert str(target.family) == expected_family
-
-
-@pytest.mark.parametrize('target_name,feature', [
-    ('skylake', 'avx2'),
-    ('icelake', 'avx512f'),
-    # Test feature aliases
-    ('icelake', 'avx512'),
-    ('skylake', 'sse3'),
-    ('power8', 'altivec'),
-    ('broadwell', 'sse4.1'),
-    ('skylake', 'clflushopt'),
-    ('aarch64', 'neon')
-])
-def test_features_query(target_name, feature):
-    target = llnl.util.cpu.targets[target_name]
-    assert feature in target
-
-
-@pytest.mark.parametrize('target_name,wrong_feature', [
-    ('skylake', 1),
-    ('bulldozer', llnl.util.cpu.targets['x86_64'])
-])
-def test_wrong_types_for_features_query(target_name, wrong_feature):
-    target = llnl.util.cpu.targets[target_name]
-    with pytest.raises(TypeError, match='only objects of string types'):
-        assert wrong_feature in target
-
-
-def test_generic_microarchitecture():
-    generic_march = llnl.util.cpu.generic_microarchitecture('foo')
-
-    assert generic_march.name == 'foo'
-    assert not generic_march.features
-    assert not generic_march.ancestors
-    assert generic_march.vendor == 'generic'
-
-
-def test_target_json_schema():
-    # The file microarchitectures.json contains static data i.e. data that is
-    # not meant to be modified by users directly. It is thus sufficient to
-    # validate it only once during unit tests.
-    json_data = llnl.util.cpu.schema.targets_json.data
-    jsonschema.validate(json_data, llnl.util.cpu.schema.schema)
-
-
-@pytest.mark.parametrize('target_name,compiler,version,expected_flags', [
-    # Test GCC
-    ('x86_64', 'gcc', '4.9.3', '-march=x86-64 -mtune=generic'),
-    ('x86_64', 'gcc', '4.2.0', '-march=x86-64 -mtune=generic'),
-    ('x86_64', 'gcc', '4.1.1', '-march=x86-64 -mtune=x86-64'),
-    ('nocona', 'gcc', '4.9.3', '-march=nocona -mtune=nocona'),
-    ('nehalem', 'gcc', '4.9.3', '-march=nehalem -mtune=nehalem'),
-    ('nehalem', 'gcc', '4.8.5', '-march=corei7 -mtune=corei7'),
-    ('sandybridge', 'gcc', '4.8.5', '-march=corei7-avx -mtune=corei7-avx'),
-    ('thunderx2', 'gcc', '4.8.5', '-march=armv8-a'),
-    ('thunderx2', 'gcc', '4.9.3', '-march=armv8-a+crc+crypto'),
-    # Test Clang / LLVM
-    ('sandybridge', 'clang', '3.9.0', '-march=sandybridge -mtune=sandybridge'),
-    ('icelake', 'clang', '6.0.0', '-march=icelake -mtune=icelake'),
-    ('icelake', 'clang', '8.0.0',
-     '-march=icelake-client -mtune=icelake-client'),
-    ('icelake', 'gcc', '8.1.0',
-     '-march=icelake-client -mtune=icelake-client'),
-    ('zen2', 'clang', '9.0.0', '-march=znver2 -mtune=znver2'),
-    ('power9le', 'clang', '8.0.0', '-mcpu=power9 -mtune=power9'),
-    ('thunderx2', 'clang', '6.0.0', '-mcpu=thunderx2t99'),
-    # Test Intel on Intel CPUs
-    ('sandybridge', 'intel', '17.0.2', '-march=corei7-avx -mtune=corei7-avx'),
-    ('sandybridge', 'intel', '18.0.5',
-     '-march=sandybridge -mtune=sandybridge'),
-    # Test Intel on AMD CPUs
-    pytest.param('steamroller', 'intel', '17.0.2', '-msse4.2',
-                 marks=pytest.mark.filterwarnings('ignore::UserWarning')),
-    pytest.param('zen', 'intel', '17.0.2', '-march=core-avx2 -mtune=core-avx2',
-                 marks=pytest.mark.filterwarnings('ignore::UserWarning')),
-    # Test that an unknown compiler returns an empty string
-    ('sandybridge', 'unknown', '4.8.5', ''),
-])
-def test_optimization_flags(target_name, compiler, version, expected_flags):
-    target = llnl.util.cpu.targets[target_name]
-    flags = target.optimization_flags(compiler, version)
-    assert flags == expected_flags
-
-
-@pytest.mark.parametrize('target_name,compiler,version', [
-    ('excavator', 'gcc', '4.8.5')
-])
-def test_unsupported_optimization_flags(target_name, compiler, version):
-    target = llnl.util.cpu.targets[target_name]
-    with pytest.raises(
-            llnl.util.cpu.UnsupportedMicroarchitecture,
-            match='cannot produce optimized binary'
-    ):
-        target.optimization_flags(compiler, version)
-
-
-@pytest.mark.parametrize('operation,expected_result', [
-    # In the tests below we won't convert the right hand side to
-    # Microarchitecture, so that automatic conversion from a known
-    # target name will be tested
-    ('cascadelake > cannonlake', False),
-    ('cascadelake < cannonlake', False),
-    ('cascadelake <= cannonlake', False),
-    ('cascadelake >= cannonlake', False),
-    ('cascadelake == cannonlake', False),
-    ('cascadelake != cannonlake', True)
-])
-def test_automatic_conversion_on_comparisons(operation, expected_result):
-    target, operator, other_target = operation.split()
-    target = llnl.util.cpu.targets[target]
-    code = 'target ' + operator + 'other_target'
-    assert eval(code) is expected_result
-
-
-@pytest.mark.parametrize('version,expected_number,expected_suffix', [
-    ('4.2.0', '4.2.0', ''),
-    ('4.2.0-apple', '4.2.0', 'apple'),
-    ('my-funny-name-with-dashes', '', 'my-funny-name-with-dashes'),
-    ('10.3.56~svnr64537', '10.3.56', '~svnr64537')
-])
-def test_version_components(version, expected_number, expected_suffix):
-    number, suffix = llnl.util.cpu.version_components(version)
-    assert number == expected_number
-    assert suffix == expected_suffix
-
-
-def test_invalid_family():
-    targets = llnl.util.cpu.targets
-    multi_parents = Microarchitecture(
-        name='chimera', parents=[targets['pentium4'], targets['power7']],
-        vendor='Imagination', features=[], compilers={}, generation=0
-    )
-    with pytest.raises(AssertionError,
-                       match='a target is expected to belong'):
-        multi_parents.family