[MS] Emit S_HEAPALLOCSITE debug info

Summary:
This emits labels around heapallocsite calls and S_HEAPALLOCSITE debug
info in codeview. Currently only changes FastISel, so emitting labels still
needs to be implemented in SelectionDAG.

Reviewers: hans, rnk

Subscribers: aprantl, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D60800

llvm-svn: 358783

4 files changed, 36 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
index 89cd7a8e3bd..8ca30d03bb0 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
@@ -1072,6 +1072,23 @@ void CodeViewDebug::emitDebugInfoForFunction(const Function *GV,
       endSymbolRecord(AnnotEnd);
     }
 
+    for (auto HeapAllocSite : FI.HeapAllocSites) {
+      MCSymbol *BeginLabel = std::get<0>(HeapAllocSite);
+      MCSymbol *EndLabel = std::get<1>(HeapAllocSite);
+      DIType *DITy = std::get<2>(HeapAllocSite);
+
+      MCSymbol *HeapAllocEnd = beginSymbolRecord(SymbolKind::S_HEAPALLOCSITE);
+      OS.AddComment("Call site offset");
+      OS.EmitCOFFSecRel32(BeginLabel, /*Offset=*/0);
+      OS.AddComment("Call site section index");
+      OS.EmitCOFFSectionIndex(BeginLabel);
+      OS.AddComment("Call instruction length");
+      OS.emitAbsoluteSymbolDiff(EndLabel, BeginLabel, 2);
+      OS.AddComment("Type index");
+      OS.EmitIntValue(getCompleteTypeIndex(DITy).getIndex(), 4);
+      endSymbolRecord(HeapAllocEnd);
+    }
+
     if (SP != nullptr)
       emitDebugInfoForUDTs(LocalUDTs);
 
@@ -2807,6 +2824,7 @@ void CodeViewDebug::endFunctionImpl(const MachineFunction *MF) {
   }
 
   CurFn->Annotations = MF->getCodeViewAnnotations();
+  CurFn->HeapAllocSites = MF->getCodeViewHeapAllocSites();
 
   CurFn->End = Asm->getFunctionEnd();
 
diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
index 35902302c21..93204036617 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
@@ -147,6 +147,7 @@ class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase {
     SmallVector<LexicalBlock *, 1> ChildBlocks;
 
     std::vector<std::pair<MCSymbol *, MDNode *>> Annotations;
+    std::vector<std::tuple<MCSymbol *, MCSymbol *, DIType *>> HeapAllocSites;
 
     const MCSymbol *Begin = nullptr;
     const MCSymbol *End = nullptr;
diff --git a/llvm/lib/CodeGen/MachineFunction.cpp b/llvm/lib/CodeGen/MachineFunction.cpp
index 88a7d15c299..6309d6405d2 100644
--- a/llvm/lib/CodeGen/MachineFunction.cpp
+++ b/llvm/lib/CodeGen/MachineFunction.cpp
@@ -43,6 +43,7 @@
 #include "llvm/IR/BasicBlock.h"
 #include "llvm/IR/Constant.h"
 #include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DebugInfoMetadata.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/GlobalValue.h"
@@ -806,6 +807,16 @@ try_next:;
   return FilterID;
 }
 
+void MachineFunction::addCodeViewHeapAllocSite(MachineInstr *I, MDNode *MD) {
+  MCSymbol *BeginLabel = Ctx.createTempSymbol("heapallocsite", true);
+  MCSymbol *EndLabel = Ctx.createTempSymbol("heapallocsite", true);
+  I->setPreInstrSymbol(*this, BeginLabel);
+  I->setPostInstrSymbol(*this, EndLabel);
+
+  DIType *DI = dyn_cast<DIType>(MD);
+  CodeViewHeapAllocSites.push_back({BeginLabel, EndLabel, DI});
+}
+
 /// \}
 
 //===----------------------------------------------------------------------===//
diff --git a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
index 30294ae1595..fb607bbf739 100644
--- a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -1234,6 +1234,12 @@ bool FastISel::lowerCallTo(CallLoweringInfo &CLI) {
   if (CLI.NumResultRegs && CLI.CS)
     updateValueMap(CLI.CS->getInstruction(), CLI.ResultReg, CLI.NumResultRegs);
 
+  // Set labels for heapallocsite call.
+  if (CLI.CS && CLI.CS->getInstruction()->getMetadata("heapallocsite")) {
+    MDNode *MD = CLI.CS->getInstruction()->getMetadata("heapallocsite");
+    MF->addCodeViewHeapAllocSite(CLI.Call, MD);
+  }
+
   return true;
 }