petsc: add variant +sycl (#40562)

* petsc: add variant +sycl

* petsc: add in gmake as dependency - so that consistent make gets used between petsc and slepc builds [that can have different env for each of the builds]

1 files changed, 16 insertions, 0 deletions

diff --git a/var/spack/repos/builtin/packages/petsc/package.py b/var/spack/repos/builtin/packages/petsc/package.py
index 9d0d3a9016..2f258edc17 100644
--- a/var/spack/repos/builtin/packages/petsc/package.py
+++ b/var/spack/repos/builtin/packages/petsc/package.py
@@ -87,6 +87,7 @@ class Petsc(Package, CudaPackage, ROCmPackage):
     variant("double", default=True, description="Switches between single and double precision")
     variant("complex", default=False, description="Build with complex numbers")
     variant("debug", default=False, description="Compile in debug mode")
+    variant("sycl", default=False, description="Enable sycl build")
 
     variant("metis", default=True, description="Activates support for metis and parmetis")
     variant(
@@ -207,6 +208,8 @@ class Petsc(Package, CudaPackage, ROCmPackage):
     patch("revert-3.18.0-ver-format-for-dealii.patch", when="@3.18.0")
 
     depends_on("diffutils", type="build")
+    # not listed as a "build" dependency - so that slepc build gets the same dependency
+    depends_on("gmake")
 
     # Virtual dependencies
     # Git repository needs sowing to build Fortran interface
@@ -338,6 +341,9 @@ class Petsc(Package, CudaPackage, ROCmPackage):
             when="+kokkos +rocm amdgpu_target=%s" % rocm_arch,
         )
 
+    conflicts("~kokkos", when="+sycl", msg="+sycl requires +kokkos")
+    depends_on("kokkos+sycl", when="+sycl +kokkos")
+
     phases = ["configure", "build", "install"]
 
     # Using the following tarballs
@@ -434,6 +440,16 @@ class Petsc(Package, CudaPackage, ROCmPackage):
         else:
             options.append("--with-x=0")
 
+        if "+sycl" in spec:
+            sycl_compatible_compilers = ["icpx"]
+            if not (os.path.basename(self.compiler.cxx) in sycl_compatible_compilers):
+                raise InstallError("PETSc's SYCL GPU Backend requires oneAPI CXX (icpx) compiler.")
+            options.append("--with-sycl=1")
+            options.append("--with-syclc=" + self.compiler.cxx)
+            options.append("SYCLPPFLAGS=-Wno-tautological-constant-compare")
+        else:
+            options.append("--with-sycl=0")
+
         if "trilinos" in spec:
             if spec.satisfies("^trilinos+boost"):
                 options.append("--with-boost=1")