Implement .cfi_same_value.

llvm-svn: 129361

3 files changed, 32 insertions, 0 deletions

diff --git a/llvm/lib/MC/MCDwarf.cpp b/llvm/lib/MC/MCDwarf.cpp
index 112d7d887a2..5ee0b30243c 100644
--- a/llvm/lib/MC/MCDwarf.cpp
+++ b/llvm/lib/MC/MCDwarf.cpp
@@ -493,6 +493,12 @@ static void EmitCFIInstruction(MCStreamer &Streamer,
   case MCCFIInstruction::Restore:
     Streamer.EmitIntValue(dwarf::DW_CFA_restore_state, 1);
     return;
+  case MCCFIInstruction::SameValue: {
+    unsigned Reg = Instr.getDestination().getReg();
+    Streamer.EmitIntValue(dwarf::DW_CFA_same_value, 1);
+    Streamer.EmitULEB128IntValue(Reg, 1);
+    return;
+  }
   }
   llvm_unreachable("Unhandled case in switch");
 }
diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp
index 418b5101514..c4a83e5df90 100644
--- a/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -283,6 +283,8 @@ public:
       &GenericAsmParser::ParseDirectiveCFIRememberState>(".cfi_remember_state");
     AddDirectiveHandler<
       &GenericAsmParser::ParseDirectiveCFIRestoreState>(".cfi_restore_state");
+    AddDirectiveHandler<
+      &GenericAsmParser::ParseDirectiveCFISameValue>(".cfi_same_value");
 
     // Macro directives.
     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveMacrosOnOff>(
@@ -314,6 +316,7 @@ public:
   bool ParseDirectiveCFIPersonalityOrLsda(StringRef, SMLoc DirectiveLoc);
   bool ParseDirectiveCFIRememberState(StringRef, SMLoc DirectiveLoc);
   bool ParseDirectiveCFIRestoreState(StringRef, SMLoc DirectiveLoc);
+  bool ParseDirectiveCFISameValue(StringRef, SMLoc DirectiveLoc);
 
   bool ParseDirectiveMacrosOnOff(StringRef, SMLoc DirectiveLoc);
   bool ParseDirectiveMacro(StringRef, SMLoc DirectiveLoc);
@@ -2472,6 +2475,20 @@ bool GenericAsmParser::ParseDirectiveCFIRestoreState(StringRef IDVal,
   return getStreamer().EmitCFIRestoreState();
 }
 
+/// ParseDirectiveCFISameValue
+/// ::= .cfi_same_value register
+bool GenericAsmParser::ParseDirectiveCFISameValue(StringRef IDVal,
+                                                  SMLoc DirectiveLoc) {
+  int64_t Register = 0;
+
+  if (ParseRegisterOrRegisterNumber(Register, DirectiveLoc))
+    return true;
+
+  getStreamer().EmitCFISameValue(Register);
+
+  return false;
+}
+
 /// ParseDirectiveMacrosOnOff
 /// ::= .macros_on
 /// ::= .macros_off
diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp
index 1bd287b2b5b..3208295296a 100644
--- a/llvm/lib/MC/MCStreamer.cpp
+++ b/llvm/lib/MC/MCStreamer.cpp
@@ -259,6 +259,15 @@ bool MCStreamer::EmitCFIRestoreState() {
   return false;
 }
 
+void MCStreamer::EmitCFISameValue(int64_t Register) {
+  EnsureValidFrame();
+  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
+  MCSymbol *Label = getContext().CreateTempSymbol();
+  EmitLabel(Label);
+  MCCFIInstruction Instruction(MCCFIInstruction::SameValue, Label, Register);
+  CurFrame->Instructions.push_back(Instruction);
+}
+
 void MCStreamer::EmitFnStart() {
   errs() << "Not implemented yet\n";
   abort();