[llvm-commits] [llvm] r130379 - in /llvm/trunk: include/llvm/MC/MCDwarf.h lib/MC/MCAssembler.cpp lib/MC/MCDwarf.cpp

[Rafael Espindola]

Author: rafael
Date: Wed Apr 27 23:04:14 2011
New Revision: 130379

URL: http://llvm.org/viewvc/llvm-project?rev=130379&view=rev
Log:
Add a small temporary hack for producing identical eh_frame sections on OS X.
This removes one of the main advantages of moving eh_frame to MC, but
makes the transition a lot easier to debug (run md5).

Modified:
    llvm/trunk/include/llvm/MC/MCDwarf.h
    llvm/trunk/lib/MC/MCAssembler.cpp
    llvm/trunk/lib/MC/MCDwarf.cpp

Modified: llvm/trunk/include/llvm/MC/MCDwarf.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCDwarf.h?rev=130379&r1=130378&r2=130379&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCDwarf.h (original)
+++ llvm/trunk/include/llvm/MC/MCDwarf.h Wed Apr 27 23:04:14 2011
@@ -23,6 +23,7 @@
 #include <vector>
 
 namespace llvm {
+  class TargetAsmInfo;
   class MachineMove;
   class MCContext;
   class MCExpr;
@@ -282,7 +283,8 @@
     //
     static void Emit(MCStreamer &streamer);
     static void EmitAdvanceLoc(MCStreamer &Streamer, uint64_t AddrDelta);
-    static void EncodeAdvanceLoc(uint64_t AddrDelta, raw_ostream &OS);
+    static void EncodeAdvanceLoc(uint64_t AddrDelta, raw_ostream &OS,
+                                 const TargetAsmInfo &AsmInfo);
   };
 } // end namespace llvm
 

Modified: llvm/trunk/lib/MC/MCAssembler.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCAssembler.cpp?rev=130379&r1=130378&r2=130379&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCAssembler.cpp (original)
+++ llvm/trunk/lib/MC/MCAssembler.cpp Wed Apr 27 23:04:14 2011
@@ -732,7 +732,8 @@
   SmallString<8> &Data = DF.getContents();
   Data.clear();
   raw_svector_ostream OSE(Data);
-  MCDwarfFrameEmitter::EncodeAdvanceLoc(AddrDelta, OSE);
+  const TargetAsmInfo &AsmInfo = getContext().getTargetAsmInfo();
+  MCDwarfFrameEmitter::EncodeAdvanceLoc(AddrDelta, OSE, AsmInfo);
   OSE.flush();
   return OldSize != Data.size();
 }

Modified: llvm/trunk/lib/MC/MCDwarf.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCDwarf.cpp?rev=130379&r1=130378&r2=130379&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCDwarf.cpp (original)
+++ llvm/trunk/lib/MC/MCDwarf.cpp Wed Apr 27 23:04:14 2011
@@ -843,21 +843,28 @@
                                          uint64_t AddrDelta) {
   SmallString<256> Tmp;
   raw_svector_ostream OS(Tmp);
-  MCDwarfFrameEmitter::EncodeAdvanceLoc(AddrDelta, OS);
+  const TargetAsmInfo &AsmInfo = Streamer.getContext().getTargetAsmInfo();
+  MCDwarfFrameEmitter::EncodeAdvanceLoc(AddrDelta, OS, AsmInfo);
   Streamer.EmitBytes(OS.str(), /*AddrSpace=*/0);
 }
 
 void MCDwarfFrameEmitter::EncodeAdvanceLoc(uint64_t AddrDelta,
-                                           raw_ostream &OS) {
+                                           raw_ostream &OS,
+                                           const TargetAsmInfo &AsmInfo) {
+  // This is a small hack to facilitate the transition to CFI on OS X. It
+  // relaxes all address advances which lets us produces identical output
+  // to the one produce by CodeGen.
+  const bool Relax = !AsmInfo.isFunctionEHFrameSymbolPrivate();
+
   // FIXME: Assumes the code alignment factor is 1.
   if (AddrDelta == 0) {
-  } else if (isUIntN(6, AddrDelta)) {
+  } else if (isUIntN(6, AddrDelta) && !Relax) {
     uint8_t Opcode = dwarf::DW_CFA_advance_loc | AddrDelta;
     OS << Opcode;
-  } else if (isUInt<8>(AddrDelta)) {
+  } else if (isUInt<8>(AddrDelta) && !Relax) {
     OS << uint8_t(dwarf::DW_CFA_advance_loc1);
     OS << uint8_t(AddrDelta);
-  } else if (isUInt<16>(AddrDelta)) {
+  } else if (isUInt<16>(AddrDelta) && !Relax) {
     // FIXME: check what is the correct behavior on a big endian machine.
     OS << uint8_t(dwarf::DW_CFA_advance_loc2);
     OS << uint8_t( AddrDelta       & 0xff);