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-rw-r--r--contrib/llvm/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp233
1 files changed, 233 insertions, 0 deletions
diff --git a/contrib/llvm/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp b/contrib/llvm/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp
new file mode 100644
index 0000000..dd5b0e2
--- /dev/null
+++ b/contrib/llvm/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp
@@ -0,0 +1,233 @@
+//===-- 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.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "asm-printer"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/CodeGen/MachineLocation.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetFrameLowering.h"
+#include "llvm/Target/TargetLoweringObjectFile.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/Support/Dwarf.h"
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+// Dwarf Emission Helper Routines
+//===----------------------------------------------------------------------===//
+
+/// EmitSLEB128 - emit the specified signed leb128 value.
+void AsmPrinter::EmitSLEB128(int Value, const char *Desc) const {
+ if (isVerbose() && Desc)
+ OutStreamer.AddComment(Desc);
+
+ if (MAI->hasLEB128()) {
+ OutStreamer.EmitSLEB128IntValue(Value);
+ return;
+ }
+
+ // If we don't have .sleb128, emit as .bytes.
+ int Sign = Value >> (8 * sizeof(Value) - 1);
+ bool IsMore;
+
+ do {
+ unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
+ Value >>= 7;
+ IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;
+ if (IsMore) Byte |= 0x80;
+ OutStreamer.EmitIntValue(Byte, 1, /*addrspace*/0);
+ } while (IsMore);
+}
+
+/// EmitULEB128 - emit the specified signed leb128 value.
+void AsmPrinter::EmitULEB128(unsigned Value, const char *Desc,
+ unsigned PadTo) const {
+ if (isVerbose() && Desc)
+ OutStreamer.AddComment(Desc);
+
+ // FIXME: Should we add a PadTo option to the streamer?
+ if (MAI->hasLEB128() && PadTo == 0) {
+ OutStreamer.EmitULEB128IntValue(Value);
+ return;
+ }
+
+ // If we don't have .uleb128 or we want to emit padding, emit as .bytes.
+ do {
+ unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
+ Value >>= 7;
+ if (Value || PadTo != 0) Byte |= 0x80;
+ OutStreamer.EmitIntValue(Byte, 1, /*addrspace*/0);
+ } while (Value);
+
+ if (PadTo) {
+ if (PadTo > 1)
+ OutStreamer.EmitFill(PadTo - 1, 0x80/*fillval*/, 0/*addrspace*/);
+ OutStreamer.EmitFill(1, 0/*fillval*/, 0/*addrspace*/);
+ }
+}
+
+/// 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, 0/*addrspace*/);
+}
+
+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 != 0)
+ OutStreamer.AddComment(Twine(Desc)+" Encoding = " +
+ Twine(DecodeDWARFEncoding(Val)));
+ else
+ OutStreamer.AddComment(Twine("Encoding = ") +
+ DecodeDWARFEncoding(Val));
+ }
+
+ OutStreamer.EmitIntValue(Val, 1, 0/*addrspace*/);
+}
+
+/// 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: assert(0 && "Invalid encoded value.");
+ case dwarf::DW_EH_PE_absptr: return TM.getTargetData()->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::EmitReference(const MCSymbol *Sym, unsigned Encoding) const {
+ const TargetLoweringObjectFile &TLOF = getObjFileLowering();
+
+ const MCExpr *Exp =
+ TLOF.getExprForDwarfReference(Sym, Encoding, OutStreamer);
+ OutStreamer.EmitAbsValue(Exp, GetSizeOfEncodedValue(Encoding));
+}
+
+void AsmPrinter::EmitReference(const GlobalValue *GV, unsigned Encoding)const{
+ const TargetLoweringObjectFile &TLOF = getObjFileLowering();
+
+ const MCExpr *Exp =
+ TLOF.getExprForDwarfGlobalReference(GV, Mang, MMI, Encoding, OutStreamer);
+ OutStreamer.EmitValue(Exp, GetSizeOfEncodedValue(Encoding), /*addrspace*/0);
+}
+
+/// 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 (const char *SecOffDir = MAI->getDwarfSectionOffsetDirective()) {
+ // FIXME: MCize.
+ OutStreamer.EmitRawText(SecOffDir + Twine(Label->getName()));
+ 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, 0/*AddrSpace*/);
+ return;
+ }
+
+ // Otherwise, emit it as a label difference from the start of the section.
+ EmitLabelDifference(Label, SectionLabel, 4);
+}
+
+//===----------------------------------------------------------------------===//
+// Dwarf Lowering Routines
+//===----------------------------------------------------------------------===//
+
+/// EmitCFIFrameMove - Emit a frame instruction.
+void AsmPrinter::EmitCFIFrameMove(const MachineMove &Move) const {
+ const TargetRegisterInfo *RI = TM.getRegisterInfo();
+
+ const MachineLocation &Dst = Move.getDestination();
+ const MachineLocation &Src = Move.getSource();
+
+ // If advancing cfa.
+ if (Dst.isReg() && Dst.getReg() == MachineLocation::VirtualFP) {
+ if (Src.getReg() == MachineLocation::VirtualFP) {
+ OutStreamer.EmitCFIDefCfaOffset(-Src.getOffset());
+ } else {
+ // Reg + Offset
+ OutStreamer.EmitCFIDefCfa(RI->getDwarfRegNum(Src.getReg(), true),
+ Src.getOffset());
+ }
+ } else if (Src.isReg() && Src.getReg() == MachineLocation::VirtualFP) {
+ assert(Dst.isReg() && "Machine move not supported yet.");
+ OutStreamer.EmitCFIDefCfaRegister(RI->getDwarfRegNum(Dst.getReg(), true));
+ } else {
+ assert(!Dst.isReg() && "Machine move not supported yet.");
+ OutStreamer.EmitCFIOffset(RI->getDwarfRegNum(Src.getReg(), true),
+ Dst.getOffset());
+ }
+}
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