[asan-asm-instrumentation] CFI directives are generated for .S files.

Summary: CFI directives are generated for .S files.

Reviewers: eugenis

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5520

llvm-svn: 219199

1 files changed, 12 insertions, 0 deletions

diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp
index f6620f07240..2bfb9ba1599 100644
--- a/llvm/lib/MC/MCStreamer.cpp
+++ b/llvm/lib/MC/MCStreamer.cpp
@@ -220,6 +220,16 @@ void MCStreamer::EmitCFIStartProc(bool IsSimple) {
   Frame.IsSimple = IsSimple;
   EmitCFIStartProcImpl(Frame);
 
+  const MCAsmInfo* MAI = Context.getAsmInfo();
+  if (MAI) {
+    for (const MCCFIInstruction& Inst : MAI->getInitialFrameState()) {
+      if (Inst.getOperation() == MCCFIInstruction::OpDefCfa ||
+          Inst.getOperation() == MCCFIInstruction::OpDefCfaRegister) {
+        Frame.CurrentCfaRegister = Inst.getRegister();
+      }
+    }
+  }
+
   DwarfFrameInfos.push_back(Frame);
 }
 
@@ -251,6 +261,7 @@ void MCStreamer::EmitCFIDefCfa(int64_t Register, int64_t Offset) {
     MCCFIInstruction::createDefCfa(Label, Register, Offset);
   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
   CurFrame->Instructions.push_back(Instruction);
+  CurFrame->CurrentCfaRegister = static_cast<unsigned>(Register);
 }
 
 void MCStreamer::EmitCFIDefCfaOffset(int64_t Offset) {
@@ -275,6 +286,7 @@ void MCStreamer::EmitCFIDefCfaRegister(int64_t Register) {
     MCCFIInstruction::createDefCfaRegister(Label, Register);
   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
   CurFrame->Instructions.push_back(Instruction);
+  CurFrame->CurrentCfaRegister = static_cast<unsigned>(Register);
 }
 
 void MCStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) {