Fix the case of a .cfi_rel_offset before any .cfi_def_cfa_offset.

llvm-svn: 129362

1 files changed, 103 insertions, 71 deletions

diff --git a/llvm/lib/MC/MCDwarf.cpp b/llvm/lib/MC/MCDwarf.cpp
index 5ee0b30243c..84f4a3f5317 100644
--- a/llvm/lib/MC/MCDwarf.cpp
+++ b/llvm/lib/MC/MCDwarf.cpp
@@ -439,12 +439,88 @@ static int getDataAlignmentFactor(MCStreamer &streamer) {
    return -size;
 }
 
-static void EmitCFIInstruction(MCStreamer &Streamer,
-                               const MCCFIInstruction &Instr) {
+static void EmitSymbol(MCStreamer &streamer, const MCSymbol &symbol,
+                       unsigned symbolEncoding) {
+  MCContext &context = streamer.getContext();
+  const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
+  unsigned format = symbolEncoding & 0x0f;
+  unsigned application = symbolEncoding & 0x70;
+  unsigned size;
+  switch (format) {
+  default:
+    assert(0 && "Unknown Encoding");
+  case dwarf::DW_EH_PE_absptr:
+  case dwarf::DW_EH_PE_signed:
+    size = asmInfo.getPointerSize();
+    break;
+  case dwarf::DW_EH_PE_udata2:
+  case dwarf::DW_EH_PE_sdata2:
+    size = 2;
+    break;
+  case dwarf::DW_EH_PE_udata4:
+  case dwarf::DW_EH_PE_sdata4:
+    size = 4;
+    break;
+  case dwarf::DW_EH_PE_udata8:
+  case dwarf::DW_EH_PE_sdata8:
+    size = 8;
+    break;
+  }
+  switch (application) {
+  default:
+    assert(0 && "Unknown Encoding");
+    break;
+  case 0:
+    streamer.EmitSymbolValue(&symbol, size);
+    break;
+  case dwarf::DW_EH_PE_pcrel:
+    streamer.EmitPCRelSymbolValue(&symbol, size);
+    break;
+  }
+}
+
+static const MachineLocation TranslateMachineLocation(
+                                                  const TargetAsmInfo &AsmInfo,
+                                                  const MachineLocation &Loc) {
+  unsigned Reg = Loc.getReg() == MachineLocation::VirtualFP ?
+    MachineLocation::VirtualFP :
+    unsigned(AsmInfo.getDwarfRegNum(Loc.getReg(), true));
+  const MachineLocation &NewLoc = Loc.isReg() ?
+    MachineLocation(Reg) : MachineLocation(Reg, Loc.getOffset());
+  return NewLoc;
+}
+
+namespace {
+  class FrameEmitterImpl {
+    int CFAOffset;
+
+  public:
+    FrameEmitterImpl() : CFAOffset(0) {
+    }
+
+    const MCSymbol &EmitCIE(MCStreamer &streamer,
+                            const MCSymbol *personality,
+                            unsigned personalityEncoding,
+                            const MCSymbol *lsda,
+                            unsigned lsdaEncoding);
+    MCSymbol *EmitFDE(MCStreamer &streamer,
+                      const MCSymbol &cieStart,
+                      const MCDwarfFrameInfo &frame);
+    void EmitCFIInstructions(MCStreamer &streamer,
+                             const std::vector<MCCFIInstruction> &Instrs,
+                             MCSymbol *BaseLabel);
+    void EmitCFIInstruction(MCStreamer &Streamer,
+                            const MCCFIInstruction &Instr);
+  };
+}
+
+void FrameEmitterImpl::EmitCFIInstruction(MCStreamer &Streamer,
+                                          const MCCFIInstruction &Instr) {
   int dataAlignmentFactor = getDataAlignmentFactor(Streamer);
 
   switch (Instr.getOperation()) {
-  case MCCFIInstruction::Move: {
+  case MCCFIInstruction::Move:
+  case MCCFIInstruction::RelMove: {
     const MachineLocation &Dst = Instr.getDestination();
     const MachineLocation &Src = Instr.getSource();
 
@@ -459,7 +535,8 @@ static void EmitCFIInstruction(MCStreamer &Streamer,
         Streamer.EmitULEB128IntValue(Src.getReg());
       }
 
-      Streamer.EmitULEB128IntValue(-Src.getOffset(), 1);
+      CFAOffset = -Src.getOffset();
+      Streamer.EmitULEB128IntValue(CFAOffset, 1);
       return;
     }
 
@@ -471,7 +548,12 @@ static void EmitCFIInstruction(MCStreamer &Streamer,
     }
 
     unsigned Reg = Src.getReg();
-    int Offset = Dst.getOffset() / dataAlignmentFactor;
+
+    const bool IsRelative = Instr.getOperation() == MCCFIInstruction::RelMove;
+    int Offset = Dst.getOffset();
+    if (IsRelative)
+      Offset -= CFAOffset;
+    Offset = Offset / dataAlignmentFactor;
 
     if (Offset < 0) {
       Streamer.EmitIntValue(dwarf::DW_CFA_offset_extended_sf, 1);
@@ -505,9 +587,9 @@ static void EmitCFIInstruction(MCStreamer &Streamer,
 
 /// EmitFrameMoves - Emit frame instructions to describe the layout of the
 /// frame.
-static void EmitCFIInstructions(MCStreamer &streamer,
-                                const std::vector<MCCFIInstruction> &Instrs,
-                                MCSymbol *BaseLabel) {
+void FrameEmitterImpl::EmitCFIInstructions(MCStreamer &streamer,
+                                    const std::vector<MCCFIInstruction> &Instrs,
+                                           MCSymbol *BaseLabel) {
   for (unsigned i = 0, N = Instrs.size(); i < N; ++i) {
     const MCCFIInstruction &Instr = Instrs[i];
     MCSymbol *Label = Instr.getLabel();
@@ -527,62 +609,11 @@ static void EmitCFIInstructions(MCStreamer &streamer,
   }
 }
 
-static void EmitSymbol(MCStreamer &streamer, const MCSymbol &symbol,
-                       unsigned symbolEncoding) {
-  MCContext &context = streamer.getContext();
-  const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
-  unsigned format = symbolEncoding & 0x0f;
-  unsigned application = symbolEncoding & 0x70;
-  unsigned size;
-  switch (format) {
-  default:
-    assert(0 && "Unknown Encoding");
-  case dwarf::DW_EH_PE_absptr:
-  case dwarf::DW_EH_PE_signed:
-    size = asmInfo.getPointerSize();
-    break;
-  case dwarf::DW_EH_PE_udata2:
-  case dwarf::DW_EH_PE_sdata2:
-    size = 2;
-    break;
-  case dwarf::DW_EH_PE_udata4:
-  case dwarf::DW_EH_PE_sdata4:
-    size = 4;
-    break;
-  case dwarf::DW_EH_PE_udata8:
-  case dwarf::DW_EH_PE_sdata8:
-    size = 8;
-    break;
-  }
-  switch (application) {
-  default:
-    assert(0 && "Unknown Encoding");
-    break;
-  case 0:
-    streamer.EmitSymbolValue(&symbol, size);
-    break;
-  case dwarf::DW_EH_PE_pcrel:
-    streamer.EmitPCRelSymbolValue(&symbol, size);
-    break;
-  }
-}
-
-static const MachineLocation TranslateMachineLocation(
-                                                  const TargetAsmInfo &AsmInfo,
-                                                  const MachineLocation &Loc) {
-  unsigned Reg = Loc.getReg() == MachineLocation::VirtualFP ?
-    MachineLocation::VirtualFP :
-    unsigned(AsmInfo.getDwarfRegNum(Loc.getReg(), true));
-  const MachineLocation &NewLoc = Loc.isReg() ?
-    MachineLocation(Reg) : MachineLocation(Reg, Loc.getOffset());
-  return NewLoc;
-}
-
-static const MCSymbol &EmitCIE(MCStreamer &streamer,
-                               const MCSymbol *personality,
-                               unsigned personalityEncoding,
-                               const MCSymbol *lsda,
-                               unsigned lsdaEncoding) {
+const MCSymbol &FrameEmitterImpl::EmitCIE(MCStreamer &streamer,
+                                          const MCSymbol *personality,
+                                          unsigned personalityEncoding,
+                                          const MCSymbol *lsda,
+                                          unsigned lsdaEncoding) {
   MCContext &context = streamer.getContext();
   const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
   const MCSection &section = *asmInfo.getEHFrameSection();
@@ -670,9 +701,9 @@ static const MCSymbol &EmitCIE(MCStreamer &streamer,
   return *sectionStart;
 }
 
-static MCSymbol *EmitFDE(MCStreamer &streamer,
-                         const MCSymbol &cieStart,
-                         const MCDwarfFrameInfo &frame) {
+MCSymbol *FrameEmitterImpl::EmitFDE(MCStreamer &streamer,
+                                    const MCSymbol &cieStart,
+                                    const MCDwarfFrameInfo &frame) {
   MCContext &context = streamer.getContext();
   MCSymbol *fdeStart = context.CreateTempSymbol();
   MCSymbol *fdeEnd = context.CreateTempSymbol();
@@ -764,6 +795,7 @@ void MCDwarfFrameEmitter::Emit(MCStreamer &streamer) {
   const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
   MCSymbol *fdeEnd = NULL;
   DenseMap<CIEKey, const MCSymbol*> CIEStarts;
+  FrameEmitterImpl Emitter;
 
   for (unsigned i = 0, n = streamer.getNumFrameInfos(); i < n; ++i) {
     const MCDwarfFrameInfo &frame = streamer.getFrameInfo(i);
@@ -771,10 +803,10 @@ void MCDwarfFrameEmitter::Emit(MCStreamer &streamer) {
                frame.LsdaEncoding);
     const MCSymbol *&cieStart = CIEStarts[key];
     if (!cieStart)
-      cieStart = &EmitCIE(streamer, frame.Personality,
-                          frame.PersonalityEncoding, frame.Lsda,
-                          frame.LsdaEncoding);
-    fdeEnd = EmitFDE(streamer, *cieStart, frame);
+      cieStart = &Emitter.EmitCIE(streamer, frame.Personality,
+                                  frame.PersonalityEncoding, frame.Lsda,
+                                  frame.LsdaEncoding);
+    fdeEnd = Emitter.EmitFDE(streamer, *cieStart, frame);
     if (i != n - 1)
       streamer.EmitLabel(fdeEnd);
   }