MC: MCCodeGenInfo naming update. NFC.

[oota-llvm.git] / lib / MC / MCDwarf.cpp

diff --git a/lib/MC/MCDwarf.cpp b/lib/MC/MCDwarf.cpp
index 5effb011826b475fbb39eaedd0857a4290a2b562..890b03170b027fd8f33cb54fa27c0b750cc4f2e6 100644 (file)
--- a/lib/MC/MCDwarf.cpp
+++ b/lib/MC/MCDwarf.cpp
@@ -179,28 +179,19 @@ EmitDwarfLineTable(MCObjectStreamer *MCOS, const MCSection *Section,
   }
 
   // Emit a DW_LNE_end_sequence for the end of the section.
-  // Using the pointer Section create a temporary label at the end of the
-  // section and use that and the LastLabel to compute the address delta
-  // and use INT64_MAX as the line delta which is the signal that this is
-  // actually a DW_LNE_end_sequence.
+  // Use the section end label to compute the address delta and use INT64_MAX
+  // as the line delta which is the signal that this is actually a
+  // DW_LNE_end_sequence.
+  MCSymbol *SectionEnd = MCOS->endSection(Section);
 
-  // Switch to the section to be able to create a symbol at its end.
-  // TODO: keep track of the last subsection so that this symbol appears in the
-  // correct place.
-  MCOS->SwitchSection(Section);
+  // Switch back the dwarf line section, in case endSection had to switch the
+  // section.
+  MCContext &Ctx = MCOS->getContext();
+  MCOS->SwitchSection(Ctx.getObjectFileInfo()->getDwarfLineSection());
 
-  MCContext &context = MCOS->getContext();
-  // Create a symbol at the end of the section.
-  MCSymbol *SectionEnd = context.CreateTempSymbol();
-  // Set the value of the symbol, as we are at the end of the section.
-  MCOS->EmitLabel(SectionEnd);
-
-  // Switch back the dwarf line section.
-  MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfLineSection());
-
-  const MCAsmInfo *asmInfo = MCOS->getContext().getAsmInfo();
+  const MCAsmInfo *AsmInfo = Ctx.getAsmInfo();
   MCOS->EmitDwarfAdvanceLineAddr(INT64_MAX, LastLabel, SectionEnd,
-                                 asmInfo->getPointerSize());
+                                 AsmInfo->getPointerSize());
 }
 
 //
@@ -243,7 +234,8 @@ std::pair<MCSymbol *, MCSymbol *> MCDwarfLineTableHeader::Emit(MCStreamer *MCOS)
       0, // length of DW_LNS_set_epilogue_begin
       1  // DW_LNS_set_isa
   };
-  assert(array_lengthof(StandardOpcodeLengths) == (DWARF2_LINE_OPCODE_BASE - 1));
+  assert(array_lengthof(StandardOpcodeLengths) ==
+         (DWARF2_LINE_OPCODE_BASE - 1));
   return Emit(MCOS, StandardOpcodeLengths);
 }
 
@@ -446,7 +438,7 @@ void MCDwarfLineAddr::Encode(MCContext &Context, int64_t LineDelta,
   if (LineDelta == INT64_MAX) {
     if (AddrDelta == MAX_SPECIAL_ADDR_DELTA)
       OS << char(dwarf::DW_LNS_const_add_pc);
-    else {
+    else if (AddrDelta) {
       OS << char(dwarf::DW_LNS_advance_pc);
       encodeULEB128(AddrDelta, OS);
     }
@@ -811,7 +803,7 @@ static void EmitGenDwarfRanges(MCStreamer *MCOS) {
 
   MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfRangesSection());
 
-  for (const auto sec : Sections) {
+  for (const auto &sec : Sections) {
 
     MCSymbol *StartSymbol = sec.second.first;
     MCSymbol *EndSymbol = sec.second.second;
@@ -1007,11 +999,13 @@ static void EmitPersonality(MCStreamer &streamer, const MCSymbol &symbol,
 namespace {
   class FrameEmitterImpl {
     int CFAOffset;
+    int InitialCFAOffset;
     bool IsEH;
     const MCSymbol *SectionStart;
   public:
     FrameEmitterImpl(bool isEH)
-        : CFAOffset(0), IsEH(isEH), SectionStart(nullptr) {}
+        : CFAOffset(0), InitialCFAOffset(0), IsEH(isEH), SectionStart(nullptr) {
+    }
 
     void setSectionStart(const MCSymbol *Label) { SectionStart = Label; }
 
@@ -1045,11 +1039,16 @@ static void emitEncodingByte(MCObjectStreamer &Streamer, unsigned Encoding) {
 void FrameEmitterImpl::EmitCFIInstruction(MCObjectStreamer &Streamer,
                                           const MCCFIInstruction &Instr) {
   int dataAlignmentFactor = getDataAlignmentFactor(Streamer);
+  auto *MRI = Streamer.getContext().getRegisterInfo();
 
   switch (Instr.getOperation()) {
   case MCCFIInstruction::OpRegister: {
     unsigned Reg1 = Instr.getRegister();
     unsigned Reg2 = Instr.getRegister2();
+    if (!IsEH) {
+      Reg1 = MRI->getDwarfRegNum(MRI->getLLVMRegNum(Reg1, true), false);
+      Reg2 = MRI->getDwarfRegNum(MRI->getLLVMRegNum(Reg2, true), false);
+    }
     Streamer.EmitIntValue(dwarf::DW_CFA_register, 1);
     Streamer.EmitULEB128IntValue(Reg1);
     Streamer.EmitULEB128IntValue(Reg2);
@@ -1082,8 +1081,11 @@ void FrameEmitterImpl::EmitCFIInstruction(MCObjectStreamer &Streamer,
     return;
   }
   case MCCFIInstruction::OpDefCfa: {
+    unsigned Reg = Instr.getRegister();
+    if (!IsEH)
+      Reg = MRI->getDwarfRegNum(MRI->getLLVMRegNum(Reg, true), false);
     Streamer.EmitIntValue(dwarf::DW_CFA_def_cfa, 1);
-    Streamer.EmitULEB128IntValue(Instr.getRegister());
+    Streamer.EmitULEB128IntValue(Reg);
     CFAOffset = -Instr.getOffset();
     Streamer.EmitULEB128IntValue(CFAOffset);
 
@@ -1091,8 +1093,11 @@ void FrameEmitterImpl::EmitCFIInstruction(MCObjectStreamer &Streamer,
   }
 
   case MCCFIInstruction::OpDefCfaRegister: {
+    unsigned Reg = Instr.getRegister();
+    if (!IsEH)
+      Reg = MRI->getDwarfRegNum(MRI->getLLVMRegNum(Reg, true), false);
     Streamer.EmitIntValue(dwarf::DW_CFA_def_cfa_register, 1);
-    Streamer.EmitULEB128IntValue(Instr.getRegister());
+    Streamer.EmitULEB128IntValue(Reg);
 
     return;
   }
@@ -1103,6 +1108,9 @@ void FrameEmitterImpl::EmitCFIInstruction(MCObjectStreamer &Streamer,
       Instr.getOperation() == MCCFIInstruction::OpRelOffset;
 
     unsigned Reg = Instr.getRegister();
+    if (!IsEH)
+      Reg = MRI->getDwarfRegNum(MRI->getLLVMRegNum(Reg, true), false);
+
     int Offset = Instr.getOffset();
     if (IsRelative)
       Offset -= CFAOffset;
@@ -1136,6 +1144,8 @@ void FrameEmitterImpl::EmitCFIInstruction(MCObjectStreamer &Streamer,
   }
   case MCCFIInstruction::OpRestore: {
     unsigned Reg = Instr.getRegister();
+    if (!IsEH)
+      Reg = MRI->getDwarfRegNum(MRI->getLLVMRegNum(Reg, true), false);
     Streamer.EmitIntValue(dwarf::DW_CFA_restore | Reg, 1);
     return;
   }
@@ -1234,6 +1244,20 @@ void FrameEmitterImpl::EmitCompactUnwind(MCObjectStreamer &Streamer,
     Streamer.EmitIntValue(0, Size); // No LSDA
 }
 
+static unsigned getCIEVersion(bool IsEH, unsigned DwarfVersion) {
+  if (IsEH)
+    return 1;
+  switch (DwarfVersion) {
+  case 2:
+    return 1;
+  case 3:
+    return 3;
+  case 4:
+    return 4;
+  }
+  llvm_unreachable("Unknown version");
+}
+
 const MCSymbol &FrameEmitterImpl::EmitCIE(MCObjectStreamer &streamer,
                                           const MCSymbol *personality,
                                           unsigned personalityEncoding,
@@ -1260,9 +1284,7 @@ const MCSymbol &FrameEmitterImpl::EmitCIE(MCObjectStreamer &streamer,
   streamer.EmitIntValue(CIE_ID, 4);
 
   // Version
-  // For DWARF2, we use CIE version 1
-  // For DWARF3+, we use CIE version 3
-  uint8_t CIEVersion = context.getDwarfVersion() <= 2 ? 1 : 3;
+  uint8_t CIEVersion = getCIEVersion(IsEH, context.getDwarfVersion());
   streamer.EmitIntValue(CIEVersion, 1);
 
   // Augmentation String
@@ -1276,10 +1298,18 @@ const MCSymbol &FrameEmitterImpl::EmitCIE(MCObjectStreamer &streamer,
     Augmentation += "R";
     if (IsSignalFrame)
       Augmentation += "S";
-    streamer.EmitBytes(Augmentation.str());
+    streamer.EmitBytes(Augmentation);
   }
   streamer.EmitIntValue(0, 1);
 
+  if (CIEVersion >= 4) {
+    // Address Size
+    streamer.EmitIntValue(context.getAsmInfo()->getPointerSize(), 1);
+
+    // Segment Descriptor Size
+    streamer.EmitIntValue(0, 1);
+  }
+
   // Code Alignment Factor
   streamer.EmitULEB128IntValue(context.getAsmInfo()->getMinInstAlignment());
 
@@ -1290,10 +1320,10 @@ const MCSymbol &FrameEmitterImpl::EmitCIE(MCObjectStreamer &streamer,
   if (CIEVersion == 1) {
     assert(MRI->getRARegister() <= 255 &&
            "DWARF 2 encodes return_address_register in one byte");
-    streamer.EmitIntValue(MRI->getDwarfRegNum(MRI->getRARegister(), true), 1);
+    streamer.EmitIntValue(MRI->getDwarfRegNum(MRI->getRARegister(), IsEH), 1);
   } else {
     streamer.EmitULEB128IntValue(
-        MRI->getDwarfRegNum(MRI->getRARegister(), true));
+        MRI->getDwarfRegNum(MRI->getRARegister(), IsEH));
   }
 
   // Augmentation Data Length (optional)
@@ -1337,6 +1367,8 @@ const MCSymbol &FrameEmitterImpl::EmitCIE(MCObjectStreamer &streamer,
     EmitCFIInstructions(streamer, Instructions, nullptr);
   }
 
+  InitialCFAOffset = CFAOffset;
+
   // Padding
   streamer.EmitValueToAlignment(IsEH ? 4 : MAI->getPointerSize());
 
@@ -1352,6 +1384,8 @@ MCSymbol *FrameEmitterImpl::EmitFDE(MCObjectStreamer &streamer,
   MCSymbol *fdeEnd = context.CreateTempSymbol();
   const MCObjectFileInfo *MOFI = context.getObjectFileInfo();
 
+  CFAOffset = InitialCFAOffset;
+
   // Length
   const MCExpr *Length = MakeStartMinusEndExpr(streamer, *fdeStart, *fdeEnd, 0);
   emitAbsValue(streamer, Length, 4);