[MLIR][OpenMP][OMPIRBuilder] Use target triple to initialize `IsGPU` flag

This patch modifies the construction of the `OpenMPIRBuilder` in MLIR to
initialize the `IsGPU` flag using target triple information passed down from
the Flang frontend. If not present, it will default to `false`.

This replicates the behavior currently implemented in Clang, where the
`CodeGenModule::createOpenMPRuntime()` method creates a different
`CGOpenMPRuntime` instance depending on the target triple, which in turn has an
effect on the `IsGPU` flag of the `OpenMPIRBuilderConfig` object.

Differential Revision: https://reviews.llvm.org/D151903

1 files changed, 17 insertions, 0 deletions

diff --git a/flang/lib/Frontend/CompilerInvocation.cpp b/flang/lib/Frontend/CompilerInvocation.cpp
index e76b67a..43fecca 100644
--- a/flang/lib/Frontend/CompilerInvocation.cpp
+++ b/flang/lib/Frontend/CompilerInvocation.cpp
@@ -782,6 +782,23 @@ static bool parseDialectArgs(CompilerInvocation &res, llvm::opt::ArgList &args,
           res.getLangOpts().OpenMPTargetDebug = 1;
       }
     }
+
+    switch (llvm::Triple(res.getTargetOpts().triple).getArch()) {
+    case llvm::Triple::nvptx:
+    case llvm::Triple::nvptx64:
+    case llvm::Triple::amdgcn:
+      if (!res.getLangOpts().OpenMPIsTargetDevice) {
+        const unsigned diagID = diags.getCustomDiagID(
+            clang::DiagnosticsEngine::Error,
+            "OpenMP AMDGPU/NVPTX is only prepared to deal with device code.");
+        diags.Report(diagID);
+      }
+      res.getLangOpts().OpenMPIsGPU = 1;
+      break;
+    default:
+      res.getLangOpts().OpenMPIsGPU = 0;
+      break;
+    }
   }
 
   // -pedantic