concretizer: rework spack solve output to handle reuse better

3 files changed, 137 insertions, 75 deletions

diff --git a/lib/spack/spack/cmd/solve.py b/lib/spack/spack/cmd/solve.py
index 123c68862d..897eebfa4b 100644
--- a/lib/spack/spack/cmd/solve.py
+++ b/lib/spack/spack/cmd/solve.py
@@ -122,13 +122,21 @@ def solve(parser, args):
             tty.msg("Best of %d considered solutions." % result.nmodels)
             tty.msg("Optimization Criteria:")
 
-            maxlen = max(len(s) for s in result.criteria)
+            maxlen = max(len(s[2]) for s in result.criteria)
             color.cprint(
-                "@*{  Priority  Criterion %sValue}" % ((maxlen - 10) * " ")
+                "@*{  Priority  Criterion %sInstalled  ToBuild}" % ((maxlen - 10) * " ")
             )
-            for i, (name, val) in enumerate(zip(result.criteria, opt)):
-                fmt = "  @K{%%-8d}  %%-%ds%%5d" % maxlen
-                color.cprint(fmt % (i + 1, name, val))
+
+            fmt = "  @K{%%-8d}  %%-%ds%%9s  %%7s" % maxlen
+            for i, (idx, build_idx, name) in enumerate(result.criteria, 1):
+                color.cprint(
+                    fmt % (
+                        i,
+                        name,
+                        "-" if build_idx is None else opt[idx],
+                        opt[idx] if build_idx is None else opt[build_idx],
+                    )
+                )
             print()
 
         for spec in result.specs:
diff --git a/lib/spack/spack/solver/asp.py b/lib/spack/spack/solver/asp.py
index 5fed553080..69f25b39b9 100644
--- a/lib/spack/spack/solver/asp.py
+++ b/lib/spack/spack/solver/asp.py
@@ -2,7 +2,7 @@
 # Spack Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
-from __future__ import print_function
+from __future__ import division, print_function
 
 import collections
 import copy
@@ -92,6 +92,67 @@ DeclaredVersion = collections.namedtuple(
     'DeclaredVersion', ['version', 'idx', 'origin']
 )
 
+# Below numbers are used to map names of criteria to the order
+# they appear in the solution. See concretize.lp
+
+#: Priority offset for "build" criteria (regular criterio shifted to
+#: higher priority for specs we have to build)
+build_priority_offset = 200
+
+#: Priority offset of "fixed" criteria (those w/o build criteria)
+fixed_priority_offset = 100
+
+
+def build_criteria_names(costs, tuples):
+    """Construct an ordered mapping from criteria names to indices in the cost list."""
+    # pull optimization criteria names out of the solution
+    priorities_names = []
+
+    num_fixed = 0
+    for pred, args in tuples:
+        if pred != "opt_criterion":
+            continue
+
+        priority, name = args[:2]
+        priority = int(priority)
+
+        # add the priority of this opt criterion and its name
+        priorities_names.append((priority, name))
+
+        # if the priority is less than fixed_priority_offset, then it
+        # has an associated build priority -- the same criterion but for
+        # nodes that we have to build.
+        if priority < fixed_priority_offset:
+            build_priority = priority + build_priority_offset
+            priorities_names.append((build_priority, name))
+        else:
+            num_fixed += 1
+
+    # sort the criteria by priority
+    priorities_names = sorted(priorities_names, reverse=True)
+
+    assert len(priorities_names) == len(costs), "Wrong number of optimization criteria!"
+
+    # split list into three parts: build criteria, fixed criteria, non-build criteria
+    num_criteria = len(priorities_names)
+    num_build = (num_criteria - num_fixed) // 2
+
+    build = priorities_names[:num_build]
+    fixed = priorities_names[num_build:num_build + num_fixed]
+    installed = priorities_names[num_build + num_fixed:]
+
+    # mapping from priority to index in cost list
+    indices = dict((p, i) for i, (p, n) in enumerate(priorities_names))
+
+    # make a list that has each name with its build and non-build priority
+    criteria = [
+        (p - fixed_priority_offset + num_build, None, name) for p, name in fixed
+    ]
+    for (i, name), (b, _) in zip(installed, build):
+        criteria.append((indices[i], indices[b], name))
+
+    return criteria
+
 
 def issequence(obj):
     if isinstance(obj, string_types):
@@ -531,13 +592,7 @@ class PyclingoDriver(object):
 
             # add best spec to the results
             result.answers.append((list(min_cost), 0, answers))
-
-            # pull optimization criteria names out of the solution
-            criteria = [
-                (int(args[0]), args[1]) for name, args in tuples
-                if name == "opt_criterion"
-            ]
-            result.criteria = [t[1] for t in sorted(criteria, reverse=True)]
+            result.criteria = build_criteria_names(min_cost, tuples)
 
             # record the number of models the solver considered
             result.nmodels = len(models)
@@ -1635,6 +1690,9 @@ class SpackSolverSetup(object):
 
 class SpecBuilder(object):
     """Class with actions to rebuild a spec from ASP results."""
+    #: Attributes that don't need actions
+    ignored_attributes = ["opt_criterion"]
+
     def __init__(self, specs):
         self._result = None
         self._command_line_specs = specs
@@ -1797,6 +1855,9 @@ class SpecBuilder(object):
 
         self._specs = {}
         for name, args in function_tuples:
+            if name in SpecBuilder.ignored_attributes:
+                continue
+
             action = getattr(self, name, None)
 
             # print out unknown actions so we can display them for debugging
diff --git a/lib/spack/spack/solver/concretize.lp b/lib/spack/spack/solver/concretize.lp
index cab54b9bd0..430f1c81c8 100644
--- a/lib/spack/spack/solver/concretize.lp
+++ b/lib/spack/spack/solver/concretize.lp
@@ -793,7 +793,12 @@ build(Package) :- not hash(Package, _), node(Package).
 % defaults and preferences.  This is implemented by bumping the priority of optimization
 % criteria for built specs -- so that they take precedence over the otherwise
 % topmost-priority criterion to reuse what is installed.
-build_priority(Package, 100) :- build(Package), node(Package).
+%
+% The priority ranges are:
+%   200+        Shifted priorities for build nodes; correspond to priorities 0 - 99.
+%   100 - 199   Unshifted priorities. Currently only includes minimizing #builds.
+%   0   -  99   Priorities for non-built nodes.
+build_priority(Package, 200) :- build(Package), node(Package).
 build_priority(Package, 0)   :- not build(Package), node(Package).
 
 #defined installed_hash/2.
@@ -807,18 +812,17 @@ build_priority(Package, 0)   :- not build(Package), node(Package).
 %      is displayed (clingo doesn't display sums over empty sets by default)
 
 % Try hard to reuse installed packages (i.e., minimize the number built)
-opt_criterion(17, "number of packages to build (vs. reuse)").
-#minimize { 0@17: #true }.
-#minimize { 1@17,Package : build(Package), optimize_for_reuse() }.
+opt_criterion(100, "number of packages to build (vs. reuse)").
+#minimize { 0@100: #true }.
+#minimize { 1@100,Package : build(Package), optimize_for_reuse() }.
 #defined optimize_for_reuse/0.
 
 % Minimize the number of deprecated versions being used
-opt_criterion(116, "(build) deprecated versions used").
-opt_criterion(16, "deprecated versions used").
-#minimize{ 0@116: #true }.
-#minimize{ 0@16: #true }.
+opt_criterion(14, "deprecated versions used").
+#minimize{ 0@214: #true }.
+#minimize{ 0@14: #true }.
 #minimize{
-    1@16+Priority,Package
+    1@14+Priority,Package
     : deprecated(Package, _),
       build_priority(Package, Priority)
 }.
@@ -827,33 +831,30 @@ opt_criterion(16, "deprecated versions used").
 % 1. Version weight
 % 2. Number of variants with a non default value, if not set
 % for the root(Package)
-opt_criterion(115, "(build) version weight").
-opt_criterion(15, "version weight").
-#minimize{ 0@115: #true }.
-#minimize{ 0@15: #true }.
+opt_criterion(13, "version weight").
+#minimize{ 0@213: #true }.
+#minimize{ 0@13: #true }.
 #minimize {
-    Weight@15+Priority
+    Weight@13+Priority
     : root(Package),version_weight(Package, Weight),
       build_priority(Package, Priority)
 }.
 
-opt_criterion(114, "(build) number of non-default variants (roots)").
-opt_criterion(14, "number of non-default variants (roots)").
-#minimize{ 0@114: #true }.
-#minimize{ 0@14: #true }.
+opt_criterion(12, "number of non-default variants (roots)").
+#minimize{ 0@212: #true }.
+#minimize{ 0@12: #true }.
 #minimize {
-    Weight@14+Priority,Package,Variant,Value
+    Weight@12+Priority,Package,Variant,Value
     : variant_not_default(Package, Variant, Value, Weight),
       root(Package),
       build_priority(Package, Priority)
 }.
 
-opt_criterion(112, "(build) preferred providers for roots").
-opt_criterion(12, "preferred providers for roots").
-#minimize{ 0@112 : #true }.
-#minimize{ 0@12: #true }.
+opt_criterion(11, "preferred providers for roots").
+#minimize{ 0@211 : #true }.
+#minimize{ 0@11: #true }.
 #minimize{
-    Weight@12+Priority,Provider,Virtual
+    Weight@11+Priority,Provider,Virtual
     : provider_weight(Provider, Virtual, Weight),
       root(Provider),
       build_priority(Provider, Priority)
@@ -862,12 +863,11 @@ opt_criterion(12, "preferred providers for roots").
 % If the value is a multivalued variant there could be multiple
 % values set as default. Since a default value has a weight of 0 we
 % need to maximize their number below to ensure they're all set
-opt_criterion(111, "(build) number of values in multi-valued variants (root)").
-opt_criterion(11, "number of values in multi-valued variants (root)").
-#minimize{ 0@111 : #true }.
-#minimize{ 0@11 : #true }.
+opt_criterion(10, "number of values in multi-valued variants (root)").
+#minimize{ 0@210 : #true }.
+#minimize{ 0@10 : #true }.
 #maximize {
-    1@11+Priority,Package,Variant,Value
+    1@10+Priority,Package,Variant,Value
     : variant_not_default(Package, Variant, Value, Weight),
       not variant_single_value(Package, Variant),
       root(Package),
@@ -875,11 +875,11 @@ opt_criterion(11, "number of values in multi-valued variants (root)").
 }.
 
 % Try to use default variants or variants that have been set
-opt_criterion(110, "(build) number of non-default variants (non-roots)").
-opt_criterion(10, "number of non-default variants (non-roots)").
-#minimize{ 0@10: #true }.
+opt_criterion(9, "number of non-default variants (non-roots)").
+#minimize{ 0@209: #true }.
+#minimize{ 0@9: #true }.
 #minimize {
-    Weight@10+Priority,Package,Variant,Value
+    Weight@9+Priority,Package,Variant,Value
     : variant_not_default(Package, Variant, Value, Weight),
       not root(Package),
       build_priority(Package, Priority)
@@ -887,62 +887,57 @@ opt_criterion(10, "number of non-default variants (non-roots)").
 
 % Minimize the weights of the providers, i.e. use as much as
 % possible the most preferred providers
-opt_criterion(109, "(build) preferred providers (non-roots)").
-opt_criterion(9, "preferred providers (non-roots)").
-#minimize{ 0@109: #true }.
-#minimize{ 0@9: #true }.
+opt_criterion(8, "preferred providers (non-roots)").
+#minimize{ 0@208: #true }.
+#minimize{ 0@8: #true }.
 #minimize{
-    Weight@9+Priority,Provider,Virtual
+    Weight@8+Priority,Provider,Virtual
     : provider_weight(Provider, Virtual, Weight), not root(Provider),
       build_priority(Provider, Priority)
 }.
 
 % Try to minimize the number of compiler mismatches in the DAG.
-opt_criterion(108, "(build) compiler mismatches").
-opt_criterion(8, "compiler mismatches").
-#minimize{ 0@108: #true }.
-#minimize{ 0@8: #true }.
+opt_criterion(7, "compiler mismatches").
+#minimize{ 0@207: #true }.
+#minimize{ 0@7: #true }.
 #minimize{
-    1@8+Priority,Package,Dependency
+    1@7+Priority,Package,Dependency
     : compiler_mismatch(Package, Dependency),
       build_priority(Package, Priority)
 }.
 
 % Try to minimize the number of compiler mismatches in the DAG.
-opt_criterion(107, "(build) OS mismatches").
-opt_criterion(7, "OS mismatches").
-#minimize{ 0@107: #true }.
-#minimize{ 0@7: #true }.
+opt_criterion(6, "OS mismatches").
+#minimize{ 0@206: #true }.
+#minimize{ 0@6: #true }.
 #minimize{
-    1@7+Priority,Package,Dependency
+    1@6+Priority,Package,Dependency
     : node_os_mismatch(Package, Dependency),
       build_priority(Package, Priority)
 }.
 
-opt_criterion(106, "(build) non-preferred OSes").
-#minimize{ 0@106: #true }.
-#minimize{ 0@6: #true }.
+opt_criterion(5, "non-preferred OS's").
+#minimize{ 0@205: #true }.
+#minimize{ 0@5: #true }.
 #minimize{
-    Weight@6+Priority,Package
+    Weight@5+Priority,Package
     : node_os_weight(Package, Weight),
       build_priority(Package, Priority)
 }.
 
 % Choose more recent versions for nodes
-opt_criterion(105, "(build) version badness").
 opt_criterion(5, "version badness").
-#minimize{ 0@105: #true }.
-#minimize{ 0@5: #true }.
+#minimize{ 0@204: #true }.
+#minimize{ 0@4: #true }.
 #minimize{
-    Weight@5+Priority,Package
+    Weight@4+Priority,Package
     : version_weight(Package, Weight),
       build_priority(Package, Priority)
 }.
 
 % Try to use preferred compilers
-opt_criterion(103, "(build) non-preferred compilers").
 opt_criterion(3, "non-preferred compilers").
-#minimize{ 0@103: #true }.
+#minimize{ 0@203: #true }.
 #minimize{ 0@3: #true }.
 #minimize{
     Weight@3+Priority,Package
@@ -952,9 +947,8 @@ opt_criterion(3, "non-preferred compilers").
 
 % Minimize the number of mismatches for targets in the DAG, try
 % to select the preferred target.
-opt_criterion(102, "(build) target mismatches").
 opt_criterion(2, "target mismatches").
-#minimize{ 0@102: #true }.
+#minimize{ 0@202: #true }.
 #minimize{ 0@2: #true }.
 #minimize{
     1@2+Priority,Package,Dependency
@@ -962,9 +956,8 @@ opt_criterion(2, "target mismatches").
       build_priority(Package, Priority)
 }.
 
-opt_criterion(101, "(build) non-preferred targets").
 opt_criterion(1, "non-preferred targets").
-#minimize{ 0@101: #true }.
+#minimize{ 0@201: #true }.
 #minimize{ 0@1: #true }.
 #minimize{
     Weight@1+Priority,Package