r352025 - Reland r345009 "[DebugInfo] Generate debug information for labels."

[Hsiangkai Wang via cfe-commits]

Author: hsiangkai
Date: Wed Jan 23 21:34:29 2019
New Revision: 352025

URL: http://llvm.org/viewvc/llvm-project?rev=352025&view=rev
Log:
Reland r345009 "[DebugInfo] Generate debug information for labels."

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.
After fixing NULL symbol problems in AddressPool when enabling
split-dwarf-file.
After fixing PR39094.
After landing D54199 and D54465 to fix Chromium build failed.

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

Added:
    cfe/trunk/test/CodeGen/debug-label-inline.c
    cfe/trunk/test/CodeGen/debug-label.c
Modified:
    cfe/trunk/lib/CodeGen/CGDebugInfo.cpp
    cfe/trunk/lib/CodeGen/CGDebugInfo.h
    cfe/trunk/lib/CodeGen/CGStmt.cpp

Modified: cfe/trunk/lib/CodeGen/CGDebugInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDebugInfo.cpp?rev=352025&r1=352024&r2=352025&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGDebugInfo.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGDebugInfo.cpp Wed Jan 23 21:34:29 2019
@@ -3862,6 +3862,32 @@ CGDebugInfo::EmitDeclareOfAutoVariable(c
   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);

Modified: cfe/trunk/lib/CodeGen/CGDebugInfo.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDebugInfo.h?rev=352025&r1=352024&r2=352025&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGDebugInfo.h (original)
+++ cfe/trunk/lib/CodeGen/CGDebugInfo.h Wed Jan 23 21:34:29 2019
@@ -425,6 +425,9 @@ 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(

Modified: cfe/trunk/lib/CodeGen/CGStmt.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGStmt.cpp?rev=352025&r1=352024&r2=352025&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGStmt.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGStmt.cpp Wed Jan 23 21:34:29 2019
@@ -528,6 +528,16 @@ void CodeGenFunction::EmitLabel(const La
   }
 
   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());
 }
 

Added: cfe/trunk/test/CodeGen/debug-label-inline.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/debug-label-inline.c?rev=352025&view=auto
==============================================================================
--- cfe/trunk/test/CodeGen/debug-label-inline.c (added)
+++ cfe/trunk/test/CodeGen/debug-label-inline.c Wed Jan 23 21:34:29 2019
@@ -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]])

Added: cfe/trunk/test/CodeGen/debug-label.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/debug-label.c?rev=352025&view=auto
==============================================================================
--- cfe/trunk/test/CodeGen/debug-label.c (added)
+++ cfe/trunk/test/CodeGen/debug-label.c Wed Jan 23 21:34:29 2019
@@ -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,