[MLIR][DebugInfo] Enable the use of DILocalVariable DIFlags

This patch enables the use of flags for local variables in debug info. They were defaulted as always zero, but allowing them is pretty trivial.

Author: walter erquinigo

flang/lib/Optimizer/Transforms/AddDebugInfo.cpp

@@ -129,7 +129,7 @@ void AddDebugInfoPass::handleDeclareOp(fir::cg::XDeclareOp declOp,
   auto localVarAttr = mlir::LLVM::DILocalVariableAttr::get(
       context, scopeAttr, mlir::StringAttr::get(context, result.second.name),
       fileAttr, getLineFromLoc(declOp.getLoc()), argNo, /* alignInBits*/ 0,
-      tyAttr);
+      tyAttr, mlir::LLVM::DIFlags::Zero);
   declOp->setLoc(builder.getFusedLoc({declOp->getLoc()}, localVarAttr));
 }
 

mlir/include/mlir-c/Dialect/LLVM.h

@@ -309,7 +309,7 @@ MLIR_CAPI_EXPORTED MlirAttribute mlirLLVMDILexicalBlockFileAttrGet(
 MLIR_CAPI_EXPORTED MlirAttribute mlirLLVMDILocalVariableAttrGet(
     MlirContext ctx, MlirAttribute scope, MlirAttribute name,
     MlirAttribute diFile, unsigned int line, unsigned int arg,
-    unsigned int alignInBits, MlirAttribute diType);
+    unsigned int alignInBits, MlirAttribute diType, int64_t flags);
 
 /// Creates a LLVM DISubprogramAttr attribute.
 MLIR_CAPI_EXPORTED MlirAttribute mlirLLVMDISubprogramAttrGet(

mlir/include/mlir/Dialect/LLVMIR/LLVMAttrDefs.td

@@ -532,17 +532,18 @@ def LLVM_DILocalVariableAttr : LLVM_Attr<"DILocalVariable", "di_local_variable",
     OptionalParameter<"unsigned">:$line,
     OptionalParameter<"unsigned">:$arg,
     OptionalParameter<"unsigned">:$alignInBits,
-    OptionalParameter<"DITypeAttr">:$type
+    OptionalParameter<"DITypeAttr">:$type,
+    OptionalParameter<"DIFlags", "DIFlags::Zero">:$flags
   );
   let builders = [
     AttrBuilderWithInferredContext<(ins
       "DIScopeAttr":$scope, "StringRef":$name, "DIFileAttr":$file,
       "unsigned":$line, "unsigned":$arg, "unsigned":$alignInBits,
-      "DITypeAttr":$type
+      "DITypeAttr":$type, "DIFlags":$flags
     ), [{
       MLIRContext *ctx = scope.getContext();
       return $_get(ctx, scope, StringAttr::get(ctx, name), file, line,
-                   arg, alignInBits, type);
+                   arg, alignInBits, type, flags);
     }]>
   ];
   let assemblyFormat = "`<` struct(params) `>`";

mlir/lib/CAPI/Dialect/LLVM.cpp

@@ -266,15 +266,14 @@ MlirAttribute mlirLLVMDILexicalBlockFileAttrGet(MlirContext ctx,
       cast<DIFileAttr>(unwrap(file)), discriminator));
 }
 
-MlirAttribute
-mlirLLVMDILocalVariableAttrGet(MlirContext ctx, MlirAttribute scope,
-                               MlirAttribute name, MlirAttribute diFile,
-                               unsigned int line, unsigned int arg,
-                               unsigned int alignInBits, MlirAttribute diType) {
+MlirAttribute mlirLLVMDILocalVariableAttrGet(
+    MlirContext ctx, MlirAttribute scope, MlirAttribute name,
+    MlirAttribute diFile, unsigned int line, unsigned int arg,
+    unsigned int alignInBits, MlirAttribute diType, int64_t flags) {
   return wrap(DILocalVariableAttr::get(
       unwrap(ctx), cast<DIScopeAttr>(unwrap(scope)),
       cast<StringAttr>(unwrap(name)), cast<DIFileAttr>(unwrap(diFile)), line,
-      arg, alignInBits, cast<DITypeAttr>(unwrap(diType))));
+      arg, alignInBits, cast<DITypeAttr>(unwrap(diType)), DIFlags(flags)));
 }
 
 MlirAttribute mlirLLVMDISubroutineTypeAttrGet(MlirContext ctx,

mlir/lib/Target/LLVMIR/DebugImporter.cpp

@@ -180,7 +180,8 @@ DILocalVariableAttr DebugImporter::translateImpl(llvm::DILocalVariable *node) {
   return DILocalVariableAttr::get(
       context, scope, getStringAttrOrNull(node->getRawName()),
       translate(node->getFile()), node->getLine(), node->getArg(),
-      node->getAlignInBits(), translate(node->getType()));
+      node->getAlignInBits(), translate(node->getType()),
+      symbolizeDIFlags(node->getFlags()).value_or(DIFlags::Zero));
 }
 
 DIVariableAttr DebugImporter::translateImpl(llvm::DIVariable *node) {

mlir/lib/Target/LLVMIR/DebugTranslation.cpp

@@ -228,8 +228,8 @@ DebugTranslation::translateImpl(DILocalVariableAttr attr) {
   return llvm::DILocalVariable::get(
       llvmCtx, translate(attr.getScope()), getMDStringOrNull(attr.getName()),
       translate(attr.getFile()), attr.getLine(), translate(attr.getType()),
-      attr.getArg(),
-      /*Flags=*/llvm::DINode::FlagZero, attr.getAlignInBits(),
+      attr.getArg(), static_cast<llvm::DINode::DIFlags>(attr.getFlags()),
+      attr.getAlignInBits(),
       /*Annotations=*/nullptr);
 }
 

mlir/test/CAPI/llvm.c

@@ -294,7 +294,7 @@ static void testDebugInfoAttributes(MlirContext ctx) {
 
   // CHECK: #llvm.di_local_variable<{{.*}}>
   MlirAttribute local_var = mlirLLVMDILocalVariableAttrGet(
-      ctx, compile_unit, foo, file, 1, 0, 8, di_type);
+      ctx, compile_unit, foo, file, 1, 0, 8, di_type, 0);
   mlirAttributeDump(local_var);
   // CHECK: #llvm.di_derived_type<{{.*}}>
   // CHECK-NOT: dwarfAddressSpace

mlir/test/Target/LLVMIR/Import/debug-info.ll

@@ -781,7 +781,7 @@ define void @string_type(ptr %arg1) {
 !6 = !DIStringType(name: "character(*)", stringLength: !4, size: 32, align: 8, stringLengthExpression: !8, stringLocationExpression: !7)
 !7 = !DIExpression(DW_OP_push_object_address, DW_OP_deref)
 !8 = !DIExpression(DW_OP_push_object_address, DW_OP_plus_uconst, 8)
-!9 = !DILocalVariable(scope: !5, name: "str", file: !2, type: !6);
+!9 = !DILocalVariable(scope: !5, name: "str", file: !2, type: !6, flags: 64);
 !10 = !DILocation(line: 1, column: 2, scope: !5)
 
 ; CHECK: #[[VAR:.+]] = #llvm.di_local_variable<{{.*}}name = "string_size"{{.*}}>
@@ -791,3 +791,4 @@ define void @string_type(ptr %arg1) {
 ; CHECK-SAME: stringLength = #[[VAR]]
 ; CHECK-SAME: stringLengthExp = <[DW_OP_push_object_address, DW_OP_plus_uconst(8)]>
 ; CHECK-SAME: stringLocationExp = <[DW_OP_push_object_address, DW_OP_deref]>>
+; CHECK: #di_local_variable1 = #llvm.di_local_variable<scope = #di_subprogram, name = "str", file = #di_file, type = #di_string_type, flags = Artificial>

mlir/test/Target/LLVMIR/llvmir-debug.mlir

@@ -603,7 +603,7 @@ llvm.func @subranges(%arg: !llvm.ptr) {
  file = #file, isOptimized = false, emissionKind = Full>
 #sp = #llvm.di_subprogram<compileUnit = #cu, scope = #file, name = "test",
  file = #file, subprogramFlags = Definition>
-#var = #llvm.di_local_variable<scope = #sp, name = "string_size", type = #bt>
+#var = #llvm.di_local_variable<scope = #sp, name = "string_size", type = #bt, flags = Artificial>
 #ty = #llvm.di_string_type<tag = DW_TAG_string_type, name = "character(*)",
  sizeInBits = 32, alignInBits = 8, stringLength = #var,
  stringLengthExp = <[DW_OP_push_object_address, DW_OP_plus_uconst(8)]>,
@@ -620,4 +620,4 @@ llvm.func @string_ty(%arg0: !llvm.ptr) {
 #loc2 = loc(fused<#sp>[#loc1])
 
 // CHECK-DAG: !DIStringType(name: "character(*)", stringLength: ![[VAR:[0-9]+]], stringLengthExpression: !DIExpression(DW_OP_push_object_address, DW_OP_plus_uconst, 8), stringLocationExpression: !DIExpression(DW_OP_push_object_address, DW_OP_deref), size: 32, align: 8)
-// CHECK-DAG: ![[VAR]] = !DILocalVariable(name: "string_size"{{.*}})
+// CHECK-DAG: ![[VAR]] = !DILocalVariable(name: "string_size"{{.*}} flags: DIFlagArtificial)