mirror of
				https://github.com/c64scene-ar/llvm-6502.git
				synced 2025-11-04 05:17:07 +00:00 
			
		
		
		
	function. NFC. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225846 91177308-0d34-0410-b5e6-96231b3b80d8
		
			
				
	
	
		
			289 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			289 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
//===-- AsmPrinterDwarf.cpp - AsmPrinter Dwarf Support --------------------===//
 | 
						|
//
 | 
						|
//                     The LLVM Compiler Infrastructure
 | 
						|
//
 | 
						|
// This file is distributed under the University of Illinois Open Source
 | 
						|
// License. See LICENSE.TXT for details.
 | 
						|
//
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
//
 | 
						|
// This file implements the Dwarf emissions parts of AsmPrinter.
 | 
						|
//
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
 | 
						|
#include "ByteStreamer.h"
 | 
						|
#include "DwarfExpression.h"
 | 
						|
#include "llvm/CodeGen/AsmPrinter.h"
 | 
						|
#include "llvm/ADT/Twine.h"
 | 
						|
#include "llvm/IR/DataLayout.h"
 | 
						|
#include "llvm/MC/MCAsmInfo.h"
 | 
						|
#include "llvm/MC/MCSection.h"
 | 
						|
#include "llvm/MC/MCStreamer.h"
 | 
						|
#include "llvm/MC/MCSymbol.h"
 | 
						|
#include "llvm/MC/MachineLocation.h"
 | 
						|
#include "llvm/Support/Dwarf.h"
 | 
						|
#include "llvm/Support/ErrorHandling.h"
 | 
						|
#include "llvm/Target/TargetFrameLowering.h"
 | 
						|
#include "llvm/Target/TargetLoweringObjectFile.h"
 | 
						|
#include "llvm/Target/TargetMachine.h"
 | 
						|
#include "llvm/Target/TargetRegisterInfo.h"
 | 
						|
#include "llvm/Target/TargetSubtargetInfo.h"
 | 
						|
using namespace llvm;
 | 
						|
 | 
						|
#define DEBUG_TYPE "asm-printer"
 | 
						|
 | 
						|
void DebugLocDwarfExpression::EmitOp(uint8_t Op, const char *Comment) {
 | 
						|
  BS.EmitInt8(
 | 
						|
      Op, Comment ? Twine(Comment) + " " + dwarf::OperationEncodingString(Op)
 | 
						|
                  : dwarf::OperationEncodingString(Op));
 | 
						|
}
 | 
						|
 | 
						|
void DebugLocDwarfExpression::EmitSigned(int Value) {
 | 
						|
  BS.EmitSLEB128(Value, Twine(Value));
 | 
						|
}
 | 
						|
 | 
						|
void DebugLocDwarfExpression::EmitUnsigned(unsigned Value) {
 | 
						|
  BS.EmitULEB128(Value, Twine(Value));
 | 
						|
}
 | 
						|
 | 
						|
bool DebugLocDwarfExpression::isFrameRegister(unsigned MachineReg) {
 | 
						|
  // This information is not available while emitting .debug_loc entries.
 | 
						|
  return false;
 | 
						|
}
 | 
						|
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
// Dwarf Emission Helper Routines
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
 | 
						|
/// EmitSLEB128 - emit the specified signed leb128 value.
 | 
						|
void AsmPrinter::EmitSLEB128(int64_t Value, const char *Desc) const {
 | 
						|
  if (isVerbose() && Desc)
 | 
						|
    OutStreamer.AddComment(Desc);
 | 
						|
 | 
						|
  OutStreamer.EmitSLEB128IntValue(Value);
 | 
						|
}
 | 
						|
 | 
						|
/// EmitULEB128 - emit the specified signed leb128 value.
 | 
						|
void AsmPrinter::EmitULEB128(uint64_t Value, const char *Desc,
 | 
						|
                             unsigned PadTo) const {
 | 
						|
  if (isVerbose() && Desc)
 | 
						|
    OutStreamer.AddComment(Desc);
 | 
						|
 | 
						|
  OutStreamer.EmitULEB128IntValue(Value, PadTo);
 | 
						|
}
 | 
						|
 | 
						|
/// EmitCFAByte - Emit a .byte 42 directive for a DW_CFA_xxx value.
 | 
						|
void AsmPrinter::EmitCFAByte(unsigned Val) const {
 | 
						|
  if (isVerbose()) {
 | 
						|
    if (Val >= dwarf::DW_CFA_offset && Val < dwarf::DW_CFA_offset + 64)
 | 
						|
      OutStreamer.AddComment("DW_CFA_offset + Reg (" +
 | 
						|
                             Twine(Val - dwarf::DW_CFA_offset) + ")");
 | 
						|
    else
 | 
						|
      OutStreamer.AddComment(dwarf::CallFrameString(Val));
 | 
						|
  }
 | 
						|
  OutStreamer.EmitIntValue(Val, 1);
 | 
						|
}
 | 
						|
 | 
						|
static const char *DecodeDWARFEncoding(unsigned Encoding) {
 | 
						|
  switch (Encoding) {
 | 
						|
  case dwarf::DW_EH_PE_absptr:
 | 
						|
    return "absptr";
 | 
						|
  case dwarf::DW_EH_PE_omit:
 | 
						|
    return "omit";
 | 
						|
  case dwarf::DW_EH_PE_pcrel:
 | 
						|
    return "pcrel";
 | 
						|
  case dwarf::DW_EH_PE_udata4:
 | 
						|
    return "udata4";
 | 
						|
  case dwarf::DW_EH_PE_udata8:
 | 
						|
    return "udata8";
 | 
						|
  case dwarf::DW_EH_PE_sdata4:
 | 
						|
    return "sdata4";
 | 
						|
  case dwarf::DW_EH_PE_sdata8:
 | 
						|
    return "sdata8";
 | 
						|
  case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata4:
 | 
						|
    return "pcrel udata4";
 | 
						|
  case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4:
 | 
						|
    return "pcrel sdata4";
 | 
						|
  case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8:
 | 
						|
    return "pcrel udata8";
 | 
						|
  case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8:
 | 
						|
    return "pcrel sdata8";
 | 
						|
  case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata4
 | 
						|
      :
 | 
						|
    return "indirect pcrel udata4";
 | 
						|
  case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 | 
						|
      :
 | 
						|
    return "indirect pcrel sdata4";
 | 
						|
  case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8
 | 
						|
      :
 | 
						|
    return "indirect pcrel udata8";
 | 
						|
  case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8
 | 
						|
      :
 | 
						|
    return "indirect pcrel sdata8";
 | 
						|
  }
 | 
						|
 | 
						|
  return "<unknown encoding>";
 | 
						|
}
 | 
						|
 | 
						|
/// EmitEncodingByte - Emit a .byte 42 directive that corresponds to an
 | 
						|
/// encoding.  If verbose assembly output is enabled, we output comments
 | 
						|
/// describing the encoding.  Desc is an optional string saying what the
 | 
						|
/// encoding is specifying (e.g. "LSDA").
 | 
						|
void AsmPrinter::EmitEncodingByte(unsigned Val, const char *Desc) const {
 | 
						|
  if (isVerbose()) {
 | 
						|
    if (Desc)
 | 
						|
      OutStreamer.AddComment(Twine(Desc) + " Encoding = " +
 | 
						|
                             Twine(DecodeDWARFEncoding(Val)));
 | 
						|
    else
 | 
						|
      OutStreamer.AddComment(Twine("Encoding = ") + DecodeDWARFEncoding(Val));
 | 
						|
  }
 | 
						|
 | 
						|
  OutStreamer.EmitIntValue(Val, 1);
 | 
						|
}
 | 
						|
 | 
						|
/// GetSizeOfEncodedValue - Return the size of the encoding in bytes.
 | 
						|
unsigned AsmPrinter::GetSizeOfEncodedValue(unsigned Encoding) const {
 | 
						|
  if (Encoding == dwarf::DW_EH_PE_omit)
 | 
						|
    return 0;
 | 
						|
 | 
						|
  switch (Encoding & 0x07) {
 | 
						|
  default:
 | 
						|
    llvm_unreachable("Invalid encoded value.");
 | 
						|
  case dwarf::DW_EH_PE_absptr:
 | 
						|
    return TM.getSubtargetImpl()->getDataLayout()->getPointerSize();
 | 
						|
  case dwarf::DW_EH_PE_udata2:
 | 
						|
    return 2;
 | 
						|
  case dwarf::DW_EH_PE_udata4:
 | 
						|
    return 4;
 | 
						|
  case dwarf::DW_EH_PE_udata8:
 | 
						|
    return 8;
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
void AsmPrinter::EmitTTypeReference(const GlobalValue *GV,
 | 
						|
                                    unsigned Encoding) const {
 | 
						|
  if (GV) {
 | 
						|
    const TargetLoweringObjectFile &TLOF = getObjFileLowering();
 | 
						|
 | 
						|
    const MCExpr *Exp =
 | 
						|
        TLOF.getTTypeGlobalReference(GV, Encoding, *Mang, TM, MMI, OutStreamer);
 | 
						|
    OutStreamer.EmitValue(Exp, GetSizeOfEncodedValue(Encoding));
 | 
						|
  } else
 | 
						|
    OutStreamer.EmitIntValue(0, GetSizeOfEncodedValue(Encoding));
 | 
						|
}
 | 
						|
 | 
						|
/// EmitSectionOffset - Emit the 4-byte offset of Label from the start of its
 | 
						|
/// section.  This can be done with a special directive if the target supports
 | 
						|
/// it (e.g. cygwin) or by emitting it as an offset from a label at the start
 | 
						|
/// of the section.
 | 
						|
///
 | 
						|
/// SectionLabel is a temporary label emitted at the start of the section that
 | 
						|
/// Label lives in.
 | 
						|
void AsmPrinter::EmitSectionOffset(const MCSymbol *Label,
 | 
						|
                                   const MCSymbol *SectionLabel) const {
 | 
						|
  // On COFF targets, we have to emit the special .secrel32 directive.
 | 
						|
  if (MAI->needsDwarfSectionOffsetDirective()) {
 | 
						|
    OutStreamer.EmitCOFFSecRel32(Label);
 | 
						|
    return;
 | 
						|
  }
 | 
						|
 | 
						|
  // Get the section that we're referring to, based on SectionLabel.
 | 
						|
  const MCSection &Section = SectionLabel->getSection();
 | 
						|
 | 
						|
  // If Label has already been emitted, verify that it is in the same section as
 | 
						|
  // section label for sanity.
 | 
						|
  assert((!Label->isInSection() || &Label->getSection() == &Section) &&
 | 
						|
         "Section offset using wrong section base for label");
 | 
						|
 | 
						|
  // If the section in question will end up with an address of 0 anyway, we can
 | 
						|
  // just emit an absolute reference to save a relocation.
 | 
						|
  if (Section.isBaseAddressKnownZero()) {
 | 
						|
    OutStreamer.EmitSymbolValue(Label, 4);
 | 
						|
    return;
 | 
						|
  }
 | 
						|
 | 
						|
  // Otherwise, emit it as a label difference from the start of the section.
 | 
						|
  EmitLabelDifference(Label, SectionLabel, 4);
 | 
						|
}
 | 
						|
 | 
						|
// Some targets do not provide a DWARF register number for every
 | 
						|
// register.  This function attempts to emit a DWARF register by
 | 
						|
// emitting a piece of a super-register or by piecing together
 | 
						|
// multiple subregisters that alias the register.
 | 
						|
void AsmPrinter::EmitDwarfRegOpPiece(ByteStreamer &Streamer,
 | 
						|
                                     const MachineLocation &MLoc,
 | 
						|
                                     unsigned PieceSizeInBits,
 | 
						|
                                     unsigned PieceOffsetInBits) const {
 | 
						|
  assert(MLoc.isReg() && "MLoc must be a register");
 | 
						|
  DebugLocDwarfExpression Expr(*this, Streamer);
 | 
						|
  Expr.AddMachineRegPiece(MLoc.getReg(), PieceSizeInBits, PieceOffsetInBits);
 | 
						|
}
 | 
						|
 | 
						|
void AsmPrinter::EmitDwarfOpPiece(ByteStreamer &Streamer,
 | 
						|
                                  unsigned PieceSizeInBits,
 | 
						|
                                  unsigned PieceOffsetInBits) const {
 | 
						|
  DebugLocDwarfExpression Expr(*this, Streamer);
 | 
						|
  Expr.AddOpPiece(PieceSizeInBits, PieceOffsetInBits);
 | 
						|
}
 | 
						|
 | 
						|
/// EmitDwarfRegOp - Emit dwarf register operation.
 | 
						|
void AsmPrinter::EmitDwarfRegOp(ByteStreamer &Streamer,
 | 
						|
                                const MachineLocation &MLoc,
 | 
						|
                                bool Indirect) const {
 | 
						|
  DebugLocDwarfExpression Expr(*this, Streamer);
 | 
						|
  const TargetRegisterInfo *TRI = TM.getSubtargetImpl()->getRegisterInfo();
 | 
						|
  int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false);
 | 
						|
  if (Reg < 0) {
 | 
						|
    // We assume that pointers are always in an addressable register.
 | 
						|
    if (Indirect || MLoc.isIndirect())
 | 
						|
      // FIXME: We have no reasonable way of handling errors in here. The
 | 
						|
      // caller might be in the middle of a dwarf expression. We should
 | 
						|
      // probably assert that Reg >= 0 once debug info generation is more
 | 
						|
      // mature.
 | 
						|
      return Expr.EmitOp(dwarf::DW_OP_nop,
 | 
						|
                         "nop (could not find a dwarf register number)");
 | 
						|
 | 
						|
    // Attempt to find a valid super- or sub-register.
 | 
						|
    return Expr.AddMachineRegPiece(MLoc.getReg());
 | 
						|
  }
 | 
						|
 | 
						|
  if (MLoc.isIndirect())
 | 
						|
    Expr.AddRegIndirect(Reg, MLoc.getOffset(), Indirect);
 | 
						|
  else if (Indirect)
 | 
						|
    Expr.AddRegIndirect(Reg, 0, false);
 | 
						|
  else
 | 
						|
    Expr.AddReg(Reg);
 | 
						|
}
 | 
						|
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
// Dwarf Lowering Routines
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
 | 
						|
void AsmPrinter::emitCFIInstruction(const MCCFIInstruction &Inst) const {
 | 
						|
  switch (Inst.getOperation()) {
 | 
						|
  default:
 | 
						|
    llvm_unreachable("Unexpected instruction");
 | 
						|
  case MCCFIInstruction::OpDefCfaOffset:
 | 
						|
    OutStreamer.EmitCFIDefCfaOffset(Inst.getOffset());
 | 
						|
    break;
 | 
						|
  case MCCFIInstruction::OpDefCfa:
 | 
						|
    OutStreamer.EmitCFIDefCfa(Inst.getRegister(), Inst.getOffset());
 | 
						|
    break;
 | 
						|
  case MCCFIInstruction::OpDefCfaRegister:
 | 
						|
    OutStreamer.EmitCFIDefCfaRegister(Inst.getRegister());
 | 
						|
    break;
 | 
						|
  case MCCFIInstruction::OpOffset:
 | 
						|
    OutStreamer.EmitCFIOffset(Inst.getRegister(), Inst.getOffset());
 | 
						|
    break;
 | 
						|
  case MCCFIInstruction::OpRegister:
 | 
						|
    OutStreamer.EmitCFIRegister(Inst.getRegister(), Inst.getRegister2());
 | 
						|
    break;
 | 
						|
  case MCCFIInstruction::OpWindowSave:
 | 
						|
    OutStreamer.EmitCFIWindowSave();
 | 
						|
    break;
 | 
						|
  case MCCFIInstruction::OpSameValue:
 | 
						|
    OutStreamer.EmitCFISameValue(Inst.getRegister());
 | 
						|
    break;
 | 
						|
  }
 | 
						|
}
 |