[MLIR][LLVM] Fix the import of LLVM IR metadata (llvm#170631)

Change `getSupportedMetadata` to return `SmallVector<unsigned>` instead
of `ArrayRef<unsigned>` and make the list non-static. This ensures
metadata identifiers are correctly obtained per LLVM context, preventing
incorrect import when multiple contexts are used (for metadata like
vector hints or work group sizes which have non-static IDs).

Author: gysit

mlir/include/mlir/Target/LLVMIR/LLVMImportInterface.h

@@ -84,10 +84,14 @@ class LLVMImportDialectInterface
 
   /// Hook for derived dialect interfaces to publish the supported metadata
   /// kinds. As every metadata kind has a unique integer identifier, the
-  /// function returns the list of supported metadata identifiers. `ctx` can be
-  /// used to obtain IDs of metadata kinds that do not have a fixed static one.
-  virtual ArrayRef<unsigned>
-  getSupportedMetadata(llvm::LLVMContext &ctx) const {
+  /// function returns the list of supported metadata identifiers. The
+  /// `llvmContext` parameter is used to obtain identifiers for metadata kinds
+  /// that do not have a fixed static identifier. Since different LLVM contexts
+  /// can assign different identifiers to these non-static metadata kinds, the
+  /// function must recompute the list of supported metadata identifiers on each
+  /// call.
+  virtual SmallVector<unsigned>
+  getSupportedMetadata(llvm::LLVMContext &llvmContext) const {
     return {};
   }
 };

mlir/lib/Target/LLVMIR/Dialect/LLVMIR/LLVMIRToLLVMTranslation.cpp

@@ -80,8 +80,9 @@ static LogicalResult convertIntrinsicImpl(OpBuilder &odsBuilder,
 
 /// Returns the list of LLVM IR metadata kinds that are convertible to MLIR LLVM
 /// dialect attributes.
-static ArrayRef<unsigned> getSupportedMetadataImpl(llvm::LLVMContext &context) {
-  static const SmallVector<unsigned> convertibleMetadata = {
+static SmallVector<unsigned>
+getSupportedMetadataImpl(llvm::LLVMContext &llvmContext) {
+  SmallVector<unsigned> convertibleMetadata = {
       llvm::LLVMContext::MD_prof,
       llvm::LLVMContext::MD_tbaa,
       llvm::LLVMContext::MD_access_group,
@@ -91,10 +92,10 @@ static ArrayRef<unsigned> getSupportedMetadataImpl(llvm::LLVMContext &context) {
       llvm::LLVMContext::MD_dereferenceable,
       llvm::LLVMContext::MD_dereferenceable_or_null,
       llvm::LLVMContext::MD_mmra,
-      context.getMDKindID(vecTypeHintMDName),
-      context.getMDKindID(workGroupSizeHintMDName),
-      context.getMDKindID(reqdWorkGroupSizeMDName),
-      context.getMDKindID(intelReqdSubGroupSizeMDName)};
+      llvmContext.getMDKindID(vecTypeHintMDName),
+      llvmContext.getMDKindID(workGroupSizeHintMDName),
+      llvmContext.getMDKindID(reqdWorkGroupSizeMDName),
+      llvmContext.getMDKindID(intelReqdSubGroupSizeMDName)};
   return convertibleMetadata;
 }
 
@@ -505,9 +506,9 @@ class LLVMDialectLLVMIRImportInterface : public LLVMImportDialectInterface {
 
   /// Returns the list of LLVM IR metadata kinds that are convertible to MLIR
   /// LLVM dialect attributes.
-  ArrayRef<unsigned>
-  getSupportedMetadata(llvm::LLVMContext &context) const final {
-    return getSupportedMetadataImpl(context);
+  SmallVector<unsigned>
+  getSupportedMetadata(llvm::LLVMContext &llvmContext) const final {
+    return getSupportedMetadataImpl(llvmContext);
   }
 };
 } // namespace