[mlir][llvm] Add debug label intrinsic

This revision adds support for the llvm.dbg.label.intrinsic
and the corresponding DILabel metadata.

Reviewed By: Dinistro

Differential Revision: https://reviews.llvm.org/D153975

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

@@ -518,6 +518,31 @@ def LLVM_DISubroutineTypeAttr : LLVM_Attr<"DISubroutineType", "di_subroutine_typ
   let assemblyFormat = "`<` struct(params) `>`";
 }
 
+//===----------------------------------------------------------------------===//
+// DILabelAttr
+//===----------------------------------------------------------------------===//
+
+def LLVM_DILabelAttr : LLVM_Attr<"DILabel", "di_label",
+                                 /*traits=*/[], "DINodeAttr"> {
+  let parameters = (ins
+    "DIScopeAttr":$scope,
+    OptionalParameter<"StringAttr">:$name,
+    OptionalParameter<"DIFileAttr">:$file,
+    OptionalParameter<"unsigned">:$line
+  );
+  let builders = [
+    AttrBuilderWithInferredContext<(ins
+      "DIScopeAttr":$scope, "StringRef":$name, "DIFileAttr":$file,
+      "unsigned":$line
+    ), [{
+      MLIRContext *ctx = scope.getContext();
+      return $_get(ctx, scope, StringAttr::get(ctx, name), file, line);
+    }]>
+  ];
+
+  let assemblyFormat = "`<` struct(params) `>`";
+}
+
 //===----------------------------------------------------------------------===//
 // MemoryEffectsAttr
 //===----------------------------------------------------------------------===//

mlir/include/mlir/Dialect/LLVMIR/LLVMIntrinsicOps.td

@@ -559,15 +559,33 @@ class LLVM_DbgIntrOp<string name, string argName, list<Trait> traits = []>
 
 def LLVM_DbgDeclareOp : LLVM_DbgIntrOp<"dbg.declare", "addr",
     [DeclareOpInterfaceMethods<PromotableOpInterface>]> {
-  let summary = "Declare the address of a local debug info variable.";
+  let summary = "Describes how the address relates to a source language variable.";
   let arguments = (ins LLVM_AnyPointer:$addr, LLVM_DILocalVariableAttr:$varInfo);
 }
 
 def LLVM_DbgValueOp : LLVM_DbgIntrOp<"dbg.value", "value"> {
-  let summary = "Describe the current value of a local debug info variable.";
+  let summary = "Describes how the value relates to a source language variable.";
   let arguments = (ins LLVM_Type:$value, LLVM_DILocalVariableAttr:$varInfo);
 }
 
+def LLVM_DbgLabelOp : LLVM_IntrOp<"dbg.label", [], [], [], 0> {
+  let summary = "Relates the program to a debug information label.";
+  let arguments = (ins LLVM_DILabelAttr:$label);
+  let llvmBuilder = [{
+    llvm::Module *module = builder.GetInsertBlock()->getModule();
+    llvm::LLVMContext &ctx = module->getContext();
+    llvm::Function *fn =
+      llvm::Intrinsic::getDeclaration(module, llvm::Intrinsic::dbg_label);
+    builder.CreateCall(fn, {
+        llvm::MetadataAsValue::get(ctx, moduleTranslation.translateDebugInfo($label))
+      });
+  }];
+  let mlirBuilder = [{
+    $_op = $_builder.create<$_qualCppClassName>($_location, $_label_attr($label));
+  }];
+  let assemblyFormat = "$label attr-dict";
+}
+
 //
 // Variadic function intrinsics.
 //

mlir/include/mlir/Dialect/LLVMIR/LLVMOpBase.td

@@ -174,6 +174,7 @@ class LLVM_OpBase<Dialect dialect, string mnemonic, list<Trait> traits = []> :
   //   - $_int_attr - substituted by a call to an integer attribute matcher;
   //   - $_float_attr - substituted by a call to a float attribute matcher;
   //   - $_var_attr - substituted by a call to a variable attribute matcher;
+  //   - $_label_attr - substituted by a call to a label attribute matcher;
   //   - $_resultType - substituted with the MLIR result type;
   //   - $_location - substituted with the MLIR location;
   //   - $_builder - substituted with the MLIR builder;

mlir/include/mlir/Target/LLVMIR/ModuleImport.h

@@ -148,6 +148,9 @@ public:
   /// fails.
   DILocalVariableAttr matchLocalVariableAttr(llvm::Value *value);
 
+  /// Converts `value` to a label attribute. Asserts if the matching fails.
+  DILabelAttr matchLabelAttr(llvm::Value *value);
+
   /// Converts `value` to an array of symbol references pointing to alias scope
   /// operations, or returns failure if the conversion fails.
   FailureOr<SmallVector<SymbolRefAttr>>

mlir/lib/Dialect/LLVMIR/IR/LLVMAttrs.cpp

@@ -43,10 +43,11 @@ void LLVMDialect::registerAttributes() {
 
 bool DINodeAttr::classof(Attribute attr) {
   return llvm::isa<DIBasicTypeAttr, DICompileUnitAttr, DICompositeTypeAttr,
-                   DIDerivedTypeAttr, DIFileAttr, DILexicalBlockAttr,
+                   DIDerivedTypeAttr, DIFileAttr, DILabelAttr,
-                   DILexicalBlockFileAttr, DILocalVariableAttr, DINamespaceAttr,
+                   DILexicalBlockAttr, DILexicalBlockFileAttr,
-                   DINullTypeAttr, DISubprogramAttr, DISubrangeAttr,
+                   DILocalVariableAttr, DINamespaceAttr, DINullTypeAttr,
-                   DISubroutineTypeAttr>(attr);
+                   DISubprogramAttr, DISubrangeAttr, DISubroutineTypeAttr>(
+      attr);
 }
 
 //===----------------------------------------------------------------------===//

mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp

@@ -3063,7 +3063,7 @@ struct LLVMOpAsmDialectInterface : public OpAsmDialectInterface {
   AliasResult getAlias(Attribute attr, raw_ostream &os) const override {
     return TypeSwitch<Attribute, AliasResult>(attr)
         .Case<DIBasicTypeAttr, DICompileUnitAttr, DICompositeTypeAttr,
-              DIDerivedTypeAttr, DIFileAttr, DILexicalBlockAttr,
+              DIDerivedTypeAttr, DIFileAttr, DILabelAttr, DILexicalBlockAttr,
               DILexicalBlockFileAttr, DILocalVariableAttr, DINamespaceAttr,
               DINullTypeAttr, DISubprogramAttr, DISubroutineTypeAttr,
               LoopAnnotationAttr, LoopVectorizeAttr, LoopInterleaveAttr,

mlir/lib/Target/LLVMIR/DebugImporter.cpp

@@ -87,6 +87,12 @@ DIFileAttr DebugImporter::translateImpl(llvm::DIFile *node) {
   return DIFileAttr::get(context, node->getFilename(), node->getDirectory());
 }
 
+DILabelAttr DebugImporter::translateImpl(llvm::DILabel *node) {
+  return DILabelAttr::get(context, translate(node->getScope()),
+                          getStringAttrOrNull(node->getRawName()),
+                          translate(node->getFile()), node->getLine());
+}
+
 DILexicalBlockAttr DebugImporter::translateImpl(llvm::DILexicalBlock *node) {
   return DILexicalBlockAttr::get(context, translate(node->getScope()),
                                  translate(node->getFile()), node->getLine(),
@@ -200,6 +206,8 @@ DINodeAttr DebugImporter::translate(llvm::DINode *node) {
       return translateImpl(casted);
     if (auto *casted = dyn_cast<llvm::DIFile>(node))
       return translateImpl(casted);
+    if (auto *casted = dyn_cast<llvm::DILabel>(node))
+      return translateImpl(casted);
     if (auto *casted = dyn_cast<llvm::DILexicalBlock>(node))
       return translateImpl(casted);
     if (auto *casted = dyn_cast<llvm::DILexicalBlockFile>(node))

mlir/lib/Target/LLVMIR/DebugImporter.h

@@ -57,6 +57,7 @@ private:
   DICompositeTypeAttr translateImpl(llvm::DICompositeType *node);
   DIDerivedTypeAttr translateImpl(llvm::DIDerivedType *node);
   DIFileAttr translateImpl(llvm::DIFile *node);
+  DILabelAttr translateImpl(llvm::DILabel *node);
   DILexicalBlockAttr translateImpl(llvm::DILexicalBlock *node);
   DILexicalBlockFileAttr translateImpl(llvm::DILexicalBlockFile *node);
   DILocalVariableAttr translateImpl(llvm::DILocalVariable *node);

mlir/lib/Target/LLVMIR/DebugTranslation.cpp

@@ -149,6 +149,12 @@ llvm::DIFile *DebugTranslation::translateImpl(DIFileAttr attr) {
                            getMDStringOrNull(attr.getDirectory()));
 }
 
+llvm::DILabel *DebugTranslation::translateImpl(DILabelAttr attr) {
+  return llvm::DILabel::get(llvmCtx, translate(attr.getScope()),
+                            getMDStringOrNull(attr.getName()),
+                            translate(attr.getFile()), attr.getLine());
+}
+
 llvm::DILexicalBlock *DebugTranslation::translateImpl(DILexicalBlockAttr attr) {
   return llvm::DILexicalBlock::getDistinct(llvmCtx, translate(attr.getScope()),
                                            translate(attr.getFile()),
@@ -247,7 +253,7 @@ llvm::DINode *DebugTranslation::translate(DINodeAttr attr) {
   llvm::DINode *node =
       TypeSwitch<DINodeAttr, llvm::DINode *>(attr)
           .Case<DIBasicTypeAttr, DICompileUnitAttr, DICompositeTypeAttr,
-                DIDerivedTypeAttr, DIFileAttr, DILexicalBlockAttr,
+                DIDerivedTypeAttr, DIFileAttr, DILabelAttr, DILexicalBlockAttr,
                 DILexicalBlockFileAttr, DILocalVariableAttr, DINamespaceAttr,
                 DINullTypeAttr, DISubprogramAttr, DISubrangeAttr,
                 DISubroutineTypeAttr>(

mlir/lib/Target/LLVMIR/DebugTranslation.h

@@ -67,6 +67,7 @@ private:
   llvm::DICompositeType *translateImpl(DICompositeTypeAttr attr);
   llvm::DIDerivedType *translateImpl(DIDerivedTypeAttr attr);
   llvm::DIFile *translateImpl(DIFileAttr attr);
+  llvm::DILabel *translateImpl(DILabelAttr attr);
   llvm::DILexicalBlock *translateImpl(DILexicalBlockAttr attr);
   llvm::DILexicalBlockFile *translateImpl(DILexicalBlockFileAttr attr);
   llvm::DILocalScope *translateImpl(DILocalScopeAttr attr);

mlir/lib/Target/LLVMIR/ModuleImport.cpp

@@ -1255,6 +1255,12 @@ DILocalVariableAttr ModuleImport::matchLocalVariableAttr(llvm::Value *value) {
   return debugImporter->translate(node);
 }
 
+DILabelAttr ModuleImport::matchLabelAttr(llvm::Value *value) {
+  auto *nodeAsVal = cast<llvm::MetadataAsValue>(value);
+  auto *node = cast<llvm::DILabel>(nodeAsVal->getMetadata());
+  return debugImporter->translate(node);
+}
+
 FailureOr<SmallVector<SymbolRefAttr>>
 ModuleImport::matchAliasScopeAttrs(llvm::Value *value) {
   auto *nodeAsVal = cast<llvm::MetadataAsValue>(value);

mlir/test/Dialect/LLVMIR/debuginfo.mlir

@@ -136,6 +136,12 @@
   scope = #block2, name = "arg2"
 >
 
+// CHECK-DAG: #[[LABEL1:.*]] =  #llvm.di_label<scope = #[[BLOCK1]], name = "label", file = #[[FILE]], line = 42>
+#label1 = #llvm.di_label<scope = #block1, name = "label", file = #file, line = 42>
+
+// CHECK-DAG: #[[LABEL2:.*]] =  #llvm.di_label<scope = #[[BLOCK2]]>
+#label2 = #llvm.di_label<scope = #block2>
+
 // CHECK: llvm.func @addr(%[[ARG:.*]]: i64)
 llvm.func @addr(%arg: i64) {
   // CHECK: %[[ALLOC:.*]] = llvm.alloca
@@ -153,5 +159,9 @@ llvm.func @value(%arg1: i32, %arg2: i32) {
   llvm.intr.dbg.value #var1 = %arg1 : i32
   // CHECK: llvm.intr.dbg.value #[[VAR2]] = %[[ARG2]]
   llvm.intr.dbg.value #var2 = %arg2 : i32
+  // CHECK: llvm.intr.dbg.label #[[LABEL1]]
+  llvm.intr.dbg.label #label1
+  // CHECK: llvm.intr.dbg.label #[[LABEL2]]
+  llvm.intr.dbg.label #label2
   llvm.return
 }

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

@@ -233,8 +233,10 @@ source_filename = "debug-info.ll"
 
 ; // -----
 
+; CHECK: #[[FILE:.+]] = #llvm.di_file<
 ; CHECK: #[[$SP:.+]] = #llvm.di_subprogram<
-; CHECK: #[[$VAR0:.+]] = #llvm.di_local_variable<scope = #[[$SP]], name = "arg", file = #{{.*}}, line = 1, arg = 1, alignInBits = 32, type = #{{.*}}>
+; CHECK: #[[$LABEL:.+]] = #llvm.di_label<scope = #[[$SP]], name = "label", file = #[[FILE]], line = 42>
+; CHECK: #[[$VAR0:.+]] = #llvm.di_local_variable<scope = #[[$SP]], name = "arg", file = #[[FILE]], line = 1, arg = 1, alignInBits = 32, type = #{{.*}}>
 ; CHECK: #[[$VAR1:.+]] = #llvm.di_local_variable<scope = #[[$SP]], name = "arg">
 
 ; CHECK-LABEL: @intrinsic
@@ -245,6 +247,8 @@ define void @intrinsic(i64 %0, ptr %1) {
   call void @llvm.dbg.value(metadata i64 %0, metadata !5, metadata !DIExpression()), !dbg !7
   ; CHECK: llvm.intr.dbg.declare #[[$VAR1]] = %[[ARG1]] : !llvm.ptr loc(#[[LOC1:.+]])
   call void @llvm.dbg.declare(metadata ptr %1, metadata !6, metadata !DIExpression()), !dbg !9
+  ; CHECK: llvm.intr.dbg.label #[[$LABEL]] loc(#[[LOC1:.+]])
+  call void @llvm.dbg.label(metadata !10), !dbg !9
   ret void
 }
 
@@ -253,6 +257,7 @@ define void @intrinsic(i64 %0, ptr %1) {
 
 declare void @llvm.dbg.value(metadata, metadata, metadata)
 declare void @llvm.dbg.declare(metadata, metadata, metadata)
+declare void @llvm.dbg.label(metadata)
 
 !llvm.dbg.cu = !{!1}
 !llvm.module.flags = !{!0}
@@ -266,6 +271,7 @@ declare void @llvm.dbg.declare(metadata, metadata, metadata)
 !7 = !DILocation(line: 1, column: 2, scope: !3)
 !8 = !DILocation(line: 2, column: 2, scope: !3)
 !9 = !DILocation(line: 3, column: 2, scope: !3)
+!10 = !DILabel(scope: !3, name: "label", file: !2, line: 42)
 
 ; // -----
 

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

@@ -176,6 +176,7 @@ llvm.func @empty_types() {
 #di_local_variable0 = #llvm.di_local_variable<scope = #di_subprogram, name = "a", file = #di_file, type = #di_basic_type>
 #di_lexical_block_file = #llvm.di_lexical_block_file<scope = #di_subprogram1, file = #di_file, discriminator = 0>
 #di_local_variable1 = #llvm.di_local_variable<scope = #di_lexical_block_file, name = "b", file = #di_file, type = #di_basic_type>
+#di_label = #llvm.di_label<scope = #di_lexical_block_file, name = "label", file = #di_file, line = 42>
 
 #loc0 = loc("foo.mlir":0:0)
 #loc1 = loc(callsite(#loc0 at fused<#di_subprogram>["foo.mlir":4:2]))
@@ -187,6 +188,8 @@ llvm.func @func_with_inlined_dbg_value(%arg0: i32) -> (i32) {
   llvm.intr.dbg.value #di_local_variable0 = %arg0 : i32 loc(fused<#di_subprogram>[#loc0])
   // CHECK: call void @llvm.dbg.value(metadata i32 %[[ARG]], metadata ![[VAR_LOC1:[0-9]+]], metadata !DIExpression()), !dbg ![[DBG_LOC1:.*]]
   llvm.intr.dbg.value #di_local_variable1 = %arg0 : i32 loc(fused<#di_lexical_block_file>[#loc1])
+  // CHECK: call void @llvm.dbg.label(metadata ![[LABEL:[0-9]+]]), !dbg ![[DBG_LOC1:.*]]
+  llvm.intr.dbg.label #di_label loc(fused<#di_lexical_block_file>[#loc1])
   llvm.return %arg0 : i32
 } loc(fused<#di_subprogram>["caller"])
 
@@ -196,3 +199,4 @@ llvm.func @func_with_inlined_dbg_value(%arg0: i32) -> (i32) {
 // CHECK-DAG: ![[LEXICAL_BLOCK_FILE:.*]] = distinct !DILexicalBlockFile(scope: ![[INNER_FUNC]], file: ![[FILE]], discriminator: 0)
 // CHECK-DAG: ![[VAR_LOC0]] = !DILocalVariable(name: "a", scope: ![[OUTER_FUNC]], file: ![[FILE]]
 // CHECK-DAG: ![[VAR_LOC1]] = !DILocalVariable(name: "b", scope: ![[LEXICAL_BLOCK_FILE]], file: ![[FILE]]
+// CHECK-DAG  ![[LABEL]] = !DILabel(scope: ![[LEXICAL_BLOCK_FILE]], name: "label", file: ![[FILE]], line: 42)

mlir/tools/mlir-tblgen/LLVMIRConversionGen.cpp

@@ -270,6 +270,8 @@ static LogicalResult emitOneMLIRBuilder(const Record &record, raw_ostream &os,
       bs << "moduleImport.matchFloatAttr";
     } else if (name == "_var_attr") {
       bs << "moduleImport.matchLocalVariableAttr";
+    } else if (name == "_label_attr") {
+      bs << "moduleImport.matchLabelAttr";
     } else if (name == "_resultType") {
       bs << "moduleImport.convertType(inst->getType())";
     } else if (name == "_location") {