[DebugInfo] Generate debug information for labels. (Fix PR37395)

Generate DILabel metadata and call llvm.dbg.label after label
statement to associate the metadata with the label.

After fixing PR37395.
After fixing problems in LiveDebugVariables.

Differential Revision: https://reviews.llvm.org/D45045

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@341519 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index ac22dde9f96ec04cc1c600f3fceef3ddd5bb6716..17a242585489c8f33d1f9c433f43abc3220fa1e4 100644 (file)
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -3769,6 +3769,32 @@ CGDebugInfo::EmitDeclareOfAutoVariable(const VarDecl *VD, llvm::Value *Storage,
   return EmitDeclare(VD, Storage, llvm::None, Builder);
 }
 
+void CGDebugInfo::EmitLabel(const LabelDecl *D, CGBuilderTy &Builder) {
+  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
+
+  if (D->hasAttr<NoDebugAttr>())
+    return;
+
+  auto *Scope = cast<llvm::DIScope>(LexicalBlockStack.back());
+  llvm::DIFile *Unit = getOrCreateFile(D->getLocation());
+
+  // Get location information.
+  unsigned Line = getLineNumber(D->getLocation());
+  unsigned Column = getColumnNumber(D->getLocation());
+
+  StringRef Name = D->getName();
+
+  // Create the descriptor for the label.
+  auto *L =
+      DBuilder.createLabel(Scope, Name, Unit, Line, CGM.getLangOpts().Optimize);
+
+  // Insert an llvm.dbg.label into the current block.
+  DBuilder.insertLabel(L,
+                       llvm::DebugLoc::get(Line, Column, Scope, CurInlinedAt),
+                       Builder.GetInsertBlock());
+}
+
 llvm::DIType *CGDebugInfo::CreateSelfType(const QualType &QualTy,
                                           llvm::DIType *Ty) {
   llvm::DIType *CachedTy = getTypeOrNull(QualTy);

diff --git a/lib/CodeGen/CGDebugInfo.h b/lib/CodeGen/CGDebugInfo.h
index 95cba9d3ba78939126cf1cbe6992236a2b14dbc1..01ec8789435c75fbd489e7176b4b0c8f88b7b43c 100644 (file)
--- a/lib/CodeGen/CGDebugInfo.h
+++ b/lib/CodeGen/CGDebugInfo.h
@@ -415,6 +415,9 @@ public:
                                                    llvm::Value *AI,
                                                    CGBuilderTy &Builder);
 
+  /// Emit call to \c llvm.dbg.label for an label.
+  void EmitLabel(const LabelDecl *D, CGBuilderTy &Builder);
+
   /// Emit call to \c llvm.dbg.declare for an imported variable
   /// declaration in a block.
   void EmitDeclareOfBlockDeclRefVariable(

diff --git a/lib/CodeGen/CGStmt.cpp b/lib/CodeGen/CGStmt.cpp
index 09c322a8529d5e684c8ec20e972ea0ad4903d884..0bcf3554dc8f56a4b118357baa6e2af0086c6445 100644 (file)
--- a/lib/CodeGen/CGStmt.cpp
+++ b/lib/CodeGen/CGStmt.cpp
@@ -531,6 +531,16 @@ void CodeGenFunction::EmitLabel(const LabelDecl *D) {
   }
 
   EmitBlock(Dest.getBlock());
+
+  // Emit debug info for labels.
+  if (CGDebugInfo *DI = getDebugInfo()) {
+    if (CGM.getCodeGenOpts().getDebugInfo() >=
+        codegenoptions::LimitedDebugInfo) {
+      DI->setLocation(D->getLocation());
+      DI->EmitLabel(D, Builder);
+    }
+  }
+
   incrementProfileCounter(D->getStmt());
 }
 

diff --git a/test/CodeGen/debug-label-inline.c b/test/CodeGen/debug-label-inline.c
new file mode 100644 (file)
index 0000000..c0b089a
--- /dev/null
+++ b/test/CodeGen/debug-label-inline.c
@@ -0,0 +1,28 @@
+// This test will test the correctness of generating DILabel and
+// llvm.dbg.label when the label is in inlined functions.
+//
+// RUN: %clang_cc1 -O2 %s -o - -emit-llvm -debug-info-kind=limited | FileCheck %s
+inline int f1(int a, int b) {
+  int sum;
+
+top:
+  sum = a + b;
+  return sum;
+}
+
+extern int ga, gb;
+
+int f2(void) {
+  int result;
+
+  result = f1(ga, gb);
+  // CHECK: call void @llvm.dbg.label(metadata [[LABEL_METADATA:!.*]]), !dbg [[LABEL_LOCATION:!.*]]
+
+  return result;
+}
+
+// CHECK: distinct !DISubprogram(name: "f1", {{.*}}, retainedNodes: [[ELEMENTS:!.*]])
+// CHECK: [[ELEMENTS]] = !{{{.*}}, [[LABEL_METADATA]]}
+// CHECK: [[LABEL_METADATA]] = !DILabel({{.*}}, name: "top", {{.*}}, line: 8)
+// CHECK: [[INLINEDAT:!.*]] = distinct !DILocation(line: 18,
+// CHECK: [[LABEL_LOCATION]] = !DILocation(line: 8, {{.*}}, inlinedAt: [[INLINEDAT]])

diff --git a/test/CodeGen/debug-label.c b/test/CodeGen/debug-label.c
new file mode 100644 (file)
index 0000000..20efa49
--- /dev/null
+++ b/test/CodeGen/debug-label.c
@@ -0,0 +1,16 @@
+// This test will test the correstness of generating DILabel and
+// llvm.dbg.label for labels.
+//
+// RUN: %clang_cc1 -emit-llvm %s -o - -emit-llvm -debug-info-kind=limited | FileCheck %s
+
+int f1(int a, int b) {
+  int sum;
+
+top:
+  // CHECK: call void @llvm.dbg.label(metadata [[LABEL_METADATA:!.*]]), !dbg [[LABEL_LOCATION:!.*]]
+  sum = a + b;
+  return sum;
+}
+
+// CHECK: [[LABEL_METADATA]] = !DILabel({{.*}}, name: "top", {{.*}}, line: 9)
+// CHECK: [[LABEL_LOCATION]] = !DILocation(line: 9,