From 3014b2f3228e1aac1a70598f50d66f1afcc16714 Mon Sep 17 00:00:00 2001
From: Akira Hatanaka <ahatanak@gmail.com>
Date: Thu, 7 Jul 2011 20:30:33 +0000
Subject: [PATCH] This patch adds a flag in MCAsmInfo that indicates whether
 dwarf register numbers should be printed instead of symbolic register names
 in MCAsmStreamer::EmitRegisterName. This is necessary because some versions
 of GNU assembler won't accept code in which symbolic register names are used
 in cfi directives. There is no change in behavior unless the flag is
 explicitly set to true by a backend.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134635 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/MC/MCAsmInfo.h | 7 +++++++
 lib/MC/MCAsmInfo.cpp        | 1 +
 lib/MC/MCAsmStreamer.cpp    | 2 +-
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/include/llvm/MC/MCAsmInfo.h b/include/llvm/MC/MCAsmInfo.h
index 775d22bea42..15b6aa13421 100644
--- a/include/llvm/MC/MCAsmInfo.h
+++ b/include/llvm/MC/MCAsmInfo.h
@@ -284,6 +284,10 @@ namespace llvm {
     // use EmitLabelOffsetDifference.
     bool DwarfUsesLabelOffsetForRanges;
 
+    /// DwarfRegNumForCFI - True if dwarf register numbers are printed
+    /// instead of symbolic register names in .cfi_* directives.
+    bool DwarfRegNumForCFI;  // Defaults to false;
+
     //===--- CBE Asm Translation Table -----------------------------------===//
 
     const char *const *AsmTransCBE;          // Defaults to empty
@@ -475,6 +479,9 @@ namespace llvm {
     bool doesDwarfUsesLabelOffsetForRanges() const {
       return DwarfUsesLabelOffsetForRanges;
     }
+    bool useDwarfRegNumForCFI() const {
+      return DwarfRegNumForCFI;
+    }
     const char *const *getAsmCBE() const {
       return AsmTransCBE;
     }
diff --git a/lib/MC/MCAsmInfo.cpp b/lib/MC/MCAsmInfo.cpp
index 73b259eaa0f..b8ce24b78f4 100644
--- a/lib/MC/MCAsmInfo.cpp
+++ b/lib/MC/MCAsmInfo.cpp
@@ -78,6 +78,7 @@ MCAsmInfo::MCAsmInfo() {
   DwarfRequiresRelocationForSectionOffset = true;
   DwarfSectionOffsetDirective = 0;
   DwarfUsesLabelOffsetForRanges = true;
+  DwarfRegNumForCFI = false;
   HasMicrosoftFastStdCallMangling = false;
 
   AsmTransCBE = 0;
diff --git a/lib/MC/MCAsmStreamer.cpp b/lib/MC/MCAsmStreamer.cpp
index acf77558c33..4ea1c9fb842 100644
--- a/lib/MC/MCAsmStreamer.cpp
+++ b/lib/MC/MCAsmStreamer.cpp
@@ -825,7 +825,7 @@ void MCAsmStreamer::EmitCFIEndProc() {
 }
 
 void MCAsmStreamer::EmitRegisterName(int64_t Register) {
-  if (InstPrinter) {
+  if (InstPrinter && !MAI.useDwarfRegNumForCFI()) {
     const TargetAsmInfo &asmInfo = getContext().getTargetAsmInfo();
     unsigned LLVMRegister = asmInfo.getLLVMRegNum(Register, true);
     InstPrinter->printRegName(OS, LLVMRegister);