MCDwarf.cpp revision 17fd7bda5ac08f873c063c64e1456f8960a0c765
17cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby//===- lib/MC/MCDwarf.cpp - MCDwarf implementation ------------------------===// 27cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby// 37cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby// The LLVM Compiler Infrastructure 47cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby// 57cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby// This file is distributed under the University of Illinois Open Source 67cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby// License. See LICENSE.TXT for details. 77cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby// 87cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby//===----------------------------------------------------------------------===// 97cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby 107cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby#include "llvm/MC/MCDwarf.h" 11c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/MC/MCAssembler.h" 12c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/MC/MCSymbol.h" 13c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/MC/MCExpr.h" 14c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/MC/MCContext.h" 15c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/MC/MCObjectWriter.h" 16c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/ADT/SmallString.h" 177cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby#include "llvm/Support/Debug.h" 187cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby#include "llvm/Support/raw_ostream.h" 19c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/Target/TargetAsmBackend.h" 207cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderbyusing namespace llvm; 217cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby 22c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// Given a special op, return the address skip amount (in units of 23c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// DWARF2_LINE_MIN_INSN_LENGTH. 24c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#define SPECIAL_ADDR(op) (((op) - DWARF2_LINE_OPCODE_BASE)/DWARF2_LINE_RANGE) 25c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 26c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// The maximum address skip amount that can be encoded with a special op. 27c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#define MAX_SPECIAL_ADDR_DELTA SPECIAL_ADDR(255) 28c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 29c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// First special line opcode - leave room for the standard opcodes. 30c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// Note: If you want to change this, you'll have to update the 31c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// "standard_opcode_lengths" table that is emitted in DwarfFileTable::Emit(). 32c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#define DWARF2_LINE_OPCODE_BASE 13 33c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 34c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// Minimum line offset in a special line info. opcode. This value 35c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// was chosen to give a reasonable range of values. 36c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#define DWARF2_LINE_BASE -5 37c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 38c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// Range of line offsets in a special line info. opcode. 39c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby# define DWARF2_LINE_RANGE 14 40c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 41c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// Define the architecture-dependent minimum instruction length (in bytes). 42c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// This value should be rather too small than too big. 43c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby# define DWARF2_LINE_MIN_INSN_LENGTH 1 44c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 45c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// Note: when DWARF2_LINE_MIN_INSN_LENGTH == 1 which is the current setting, 46c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// this routine is a nop and will be optimized away. 47c095793b4ab027181605c79c9808df12afe45d63Kevin Enderbystatic inline uint64_t ScaleAddrDelta(uint64_t AddrDelta) 48c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby{ 49c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (DWARF2_LINE_MIN_INSN_LENGTH == 1) 50c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return AddrDelta; 51c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (AddrDelta % DWARF2_LINE_MIN_INSN_LENGTH != 0) { 52c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // TODO: report this error, but really only once. 53c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby ; 54c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 55c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return AddrDelta / DWARF2_LINE_MIN_INSN_LENGTH; 56c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 57c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 58c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 59c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// This is called when an instruction is assembled into the specified section 60c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// and if there is information from the last .loc directive that has yet to have 61c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// a line entry made for it is made. 62c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 63195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindolavoid MCLineEntry::Make(MCStreamer *MCOS, const MCSection *Section) { 64c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (!MCOS->getContext().getDwarfLocSeen()) 65c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return; 66c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 67c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a symbol at in the current section for use in the line entry. 68c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *LineSym = MCOS->getContext().CreateTempSymbol(); 69c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Set the value of the symbol to use for the MCLineEntry. 70c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitLabel(LineSym); 71c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 72c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Get the current .loc info saved in the context. 73c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCDwarfLoc &DwarfLoc = MCOS->getContext().getCurrentDwarfLoc(); 74c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 75c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a (local) line entry with the symbol and the current .loc info. 76c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCLineEntry LineEntry(LineSym, DwarfLoc); 77c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 78c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // clear DwarfLocSeen saying the current .loc info is now used. 793f55c24df9527de345f6cc960944840a7a101c6aKevin Enderby MCOS->getContext().ClearDwarfLocSeen(); 80c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 81c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Get the MCLineSection for this section, if one does not exist for this 82c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // section create it. 8317fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola const DenseMap<const MCSection *, MCLineSection *> &MCLineSections = 84c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->getContext().getMCLineSections(); 8517fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola MCLineSection *LineSection = MCLineSections.lookup(Section); 86c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (!LineSection) { 87c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a new MCLineSection. This will be deleted after the dwarf line 88c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // table is created using it by iterating through the MCLineSections 89c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // DenseMap. 90c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby LineSection = new MCLineSection; 91c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Save a pointer to the new LineSection into the MCLineSections DenseMap. 9217fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola MCOS->getContext().addMCLineSection(Section, LineSection); 93c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 94c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 95c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Add the line entry to this section's entries. 96c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby LineSection->addLineEntry(LineEntry); 97c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 98c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 99c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 100c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// This helper routine returns an expression of End - Start + IntVal . 101c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 102195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindolastatic inline const MCExpr *MakeStartMinusEndExpr(MCStreamer *MCOS, 103c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *Start, 104c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *End, int IntVal) { 105c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None; 106c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCExpr *Res = 107c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbolRefExpr::Create(End, Variant, MCOS->getContext()); 108c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCExpr *RHS = 109c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbolRefExpr::Create(Start, Variant, MCOS->getContext()); 110c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCExpr *Res1 = 111c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCBinaryExpr::Create(MCBinaryExpr::Sub, Res, RHS, MCOS->getContext()); 112c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCExpr *Res2 = 113c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCConstantExpr::Create(IntVal, MCOS->getContext()); 114c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCExpr *Res3 = 115c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCBinaryExpr::Create(MCBinaryExpr::Sub, Res1, Res2, MCOS->getContext()); 116c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return Res3; 117c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 118c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 119c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 120c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// This emits an "absolute" address used in the start of a dwarf line number 121c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// table. This will result in a relocatation entry for the address. 122c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 123195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindolastatic inline void EmitDwarfSetAddress(MCStreamer *MCOS, 124195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola MCSymbol *Symbol, 125195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola int PointerSize) { 126c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_extended_op, 1); 127c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 128195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola MCOS->EmitULEB128IntValue(PointerSize + 1); 129c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 130c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNE_set_address, 1); 131195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola MCOS->EmitSymbolValue(Symbol, PointerSize); 132c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 133c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 134c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 135c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// This emits the Dwarf line table for the specified section from the entries 136c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// in the LineSection. 137c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 138195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindolastatic inline void EmitDwarfLineTable(MCStreamer *MCOS, 139c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCSection *Section, 14017fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola const MCLineSection *LineSection, 141195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola const MCSection *DwarfLineSection, 142195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola MCSectionData *DLS, 143195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola int PointerSize) { 144c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby unsigned FileNum = 1; 145c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby unsigned LastLine = 1; 146c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby unsigned Column = 0; 147c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby unsigned Flags = DWARF2_LINE_DEFAULT_IS_STMT ? DWARF2_FLAG_IS_STMT : 0; 148c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby unsigned Isa = 0; 149c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *LastLabel = NULL; 150c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 151c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Loop through each MCLineEntry and encode the dwarf line number table. 15217fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola for (MCLineSection::const_iterator 153c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby it = LineSection->getMCLineEntries()->begin(), 154c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby ie = LineSection->getMCLineEntries()->end(); it != ie; ++it) { 155c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 156c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (FileNum != it->getFileNum()) { 157c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby FileNum = it->getFileNum(); 158c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_set_file, 1); 1593ff57094a7d176a759ddb1e1668489d89064f56cRafael Espindola MCOS->EmitULEB128IntValue(FileNum); 160c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 161c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (Column != it->getColumn()) { 162c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Column = it->getColumn(); 163c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_set_column, 1); 1643ff57094a7d176a759ddb1e1668489d89064f56cRafael Espindola MCOS->EmitULEB128IntValue(Column); 165c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 166c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (Isa != it->getIsa()) { 167c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Isa = it->getIsa(); 168c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_set_isa, 1); 1693ff57094a7d176a759ddb1e1668489d89064f56cRafael Espindola MCOS->EmitULEB128IntValue(Isa); 170c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 171c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if ((it->getFlags() ^ Flags) & DWARF2_FLAG_IS_STMT) { 172c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Flags = it->getFlags(); 173c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_negate_stmt, 1); 174c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 175c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (it->getFlags() & DWARF2_FLAG_BASIC_BLOCK) 176c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_set_basic_block, 1); 177c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (it->getFlags() & DWARF2_FLAG_PROLOGUE_END) 178c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_set_prologue_end, 1); 179c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (it->getFlags() & DWARF2_FLAG_EPILOGUE_BEGIN) 180c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_set_epilogue_begin, 1); 181c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 18264185cc6090f695c4f97c51cf2adc731f56d1a20Rafael Espindola int64_t LineDelta = static_cast<int64_t>(it->getLine()) - LastLine; 183c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *Label = it->getLabel(); 184c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 185c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // At this point we want to emit/create the sequence to encode the delta in 186c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // line numbers and the increment of the address from the previous Label 187c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // and the current Label. 188195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola if (LastLabel == NULL || DLS == NULL) { 189c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // emit the sequence to set the address 190195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola EmitDwarfSetAddress(MCOS, Label, PointerSize); 191c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // emit the sequence for the LineDelta (from 1) and a zero address delta. 192c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCDwarfLineAddr::Emit(MCOS, LineDelta, 0); 193c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 194c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby else { 195c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create an expression for the address delta from the LastLabel and 196c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // this Label (plus 0). 197c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCExpr *AddrDelta = MakeStartMinusEndExpr(MCOS, LastLabel, Label,0); 198c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a Dwarf Line fragment for the LineDelta and AddrDelta. 199195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola new MCDwarfLineAddrFragment(LineDelta, *AddrDelta, DLS); 200c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 201c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 202c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby LastLine = it->getLine(); 203c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby LastLabel = Label; 204c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 205c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 206c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Emit a DW_LNE_end_sequence for the end of the section. 207c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Using the pointer Section create a temporary label at the end of the 208c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // section and use that and the LastLabel to compute the address delta 209c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // and use INT64_MAX as the line delta which is the signal that this is 210c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // actually a DW_LNE_end_sequence. 211c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 212c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Switch to the section to be able to create a symbol at its end. 213c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->SwitchSection(Section); 214c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a symbol at the end of the section. 215c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *SectionEnd = MCOS->getContext().CreateTempSymbol(); 216c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Set the value of the symbol, as we are at the end of the section. 217c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitLabel(SectionEnd); 218c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 219c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Switch back the the dwarf line section. 220c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->SwitchSection(DwarfLineSection); 221195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola 222195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola if (DLS == NULL) { 223195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola // emit the sequence to set the address 224195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola EmitDwarfSetAddress(MCOS, SectionEnd, PointerSize); 225195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola // emit the sequence for the LineDelta (from 1) and a zero address delta. 226195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola MCDwarfLineAddr::Emit(MCOS, INT64_MAX, 0); 227195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola } else { 228195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola // Create an expression for the address delta from the LastLabel and this 229195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola // SectionEnd label. 230195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola const MCExpr *AddrDelta = MakeStartMinusEndExpr(MCOS, LastLabel, SectionEnd, 231195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola 0); 232195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola // Create a Dwarf Line fragment for the LineDelta and AddrDelta. 233195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola new MCDwarfLineAddrFragment(INT64_MAX, *AddrDelta, DLS); 234195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola } 235c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 236c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 237c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 238c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// This emits the Dwarf file and the line tables. 239c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 240195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindolavoid MCDwarfFileTable::Emit(MCStreamer *MCOS, 241195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola const MCSection *DwarfLineSection, 242195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola MCSectionData *DLS, 243195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola int PointerSize) { 244c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Switch to the section where the table will be emitted into. 245c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->SwitchSection(DwarfLineSection); 246c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 247c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a symbol at the beginning of this section. 248c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *LineStartSym = MCOS->getContext().CreateTempSymbol(); 249c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Set the value of the symbol, as we are at the start of the section. 250c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitLabel(LineStartSym); 251c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 252c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a symbol for the end of the section (to be set when we get there). 253c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *LineEndSym = MCOS->getContext().CreateTempSymbol(); 254c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 255c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // The first 4 bytes is the total length of the information for this 256c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // compilation unit (not including these 4 bytes for the length). 257c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitValue(MakeStartMinusEndExpr(MCOS, LineStartSym, LineEndSym, 4), 258c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 4, 0); 259c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 260c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Next 2 bytes is the Version, which is Dwarf 2. 261c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(2, 2); 262c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 263c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a symbol for the end of the prologue (to be set when we get there). 264c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *ProEndSym = MCOS->getContext().CreateTempSymbol(); // Lprologue_end 265c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 266c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Length of the prologue, is the next 4 bytes. Which is the start of the 267c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // section to the end of the prologue. Not including the 4 bytes for the 268c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // total length, the 2 bytes for the version, and these 4 bytes for the 269c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // length of the prologue. 270c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitValue(MakeStartMinusEndExpr(MCOS, LineStartSym, ProEndSym, 271c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby (4 + 2 + 4)), 272c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 4, 0); 273c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 274c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Parameters of the state machine, are next. 275c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(DWARF2_LINE_MIN_INSN_LENGTH, 1); 276c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(DWARF2_LINE_DEFAULT_IS_STMT, 1); 277c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(DWARF2_LINE_BASE, 1); 278c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(DWARF2_LINE_RANGE, 1); 279c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(DWARF2_LINE_OPCODE_BASE, 1); 280c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 281c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Standard opcode lengths 282c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // length of DW_LNS_copy 283c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(1, 1); // length of DW_LNS_advance_pc 284c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(1, 1); // length of DW_LNS_advance_line 285c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(1, 1); // length of DW_LNS_set_file 286c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(1, 1); // length of DW_LNS_set_column 287c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // length of DW_LNS_negate_stmt 288c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // length of DW_LNS_set_basic_block 289c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // length of DW_LNS_const_add_pc 290c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(1, 1); // length of DW_LNS_fixed_advance_pc 291c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // length of DW_LNS_set_prologue_end 292c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // length of DW_LNS_set_epilogue_begin 293c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(1, 1); // DW_LNS_set_isa 294c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 295c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Put out the directory and file tables. 296c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 297c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // First the directory table. 298c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const std::vector<StringRef> &MCDwarfDirs = 299c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->getContext().getMCDwarfDirs(); 300c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby for (unsigned i = 0; i < MCDwarfDirs.size(); i++) { 301c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitBytes(MCDwarfDirs[i], 0); // the DirectoryName 302c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitBytes(StringRef("\0", 1), 0); // the null term. of the string 303c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 304c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // Terminate the directory list 305c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 306c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Second the file table. 307c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const std::vector<MCDwarfFile *> &MCDwarfFiles = 308c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->getContext().getMCDwarfFiles(); 309c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby for (unsigned i = 1; i < MCDwarfFiles.size(); i++) { 310c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitBytes(MCDwarfFiles[i]->getName(), 0); // FileName 311c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitBytes(StringRef("\0", 1), 0); // the null term. of the string 3123ff57094a7d176a759ddb1e1668489d89064f56cRafael Espindola // the Directory num 3133ff57094a7d176a759ddb1e1668489d89064f56cRafael Espindola MCOS->EmitULEB128IntValue(MCDwarfFiles[i]->getDirIndex()); 314c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // last modification timestamp (always 0) 315c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // filesize (always 0) 316c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 317c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // Terminate the file list 318c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 319c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // This is the end of the prologue, so set the value of the symbol at the 320c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // end of the prologue (that was used in a previous expression). 321c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitLabel(ProEndSym); 322c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 323c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Put out the line tables. 32417fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola const DenseMap<const MCSection *, MCLineSection *> &MCLineSections = 325c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->getContext().getMCLineSections(); 32617fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola const std::vector<const MCSection *> &MCLineSectionOrder = 32717fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola MCOS->getContext().getMCLineSectionOrder(); 32817fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola for (std::vector<const MCSection*>::const_iterator it = 32917fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola MCLineSectionOrder.begin(), ie = MCLineSectionOrder.end(); it != ie; 33017fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola ++it) { 33117fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola const MCSection *Sec = *it; 33217fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola const MCLineSection *Line = MCLineSections.lookup(Sec); 33317fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola EmitDwarfLineTable(MCOS, Sec, Line, DwarfLineSection, DLS, 334195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola PointerSize); 335c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 336c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Now delete the MCLineSections that were created in MCLineEntry::Make() 337c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // and used to emit the line table. 33817fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola delete Line; 339c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 340c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 341c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // This is the end of the section, so set the value of the symbol at the end 342c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // of this section (that was used in a previous expression). 343c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitLabel(LineEndSym); 344c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 345c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 346c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby/// Utility function to compute the size of the encoding. 347c095793b4ab027181605c79c9808df12afe45d63Kevin Enderbyuint64_t MCDwarfLineAddr::ComputeSize(int64_t LineDelta, uint64_t AddrDelta) { 348c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby SmallString<256> Tmp; 349c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_svector_ostream OS(Tmp); 350c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCDwarfLineAddr::Encode(LineDelta, AddrDelta, OS); 351c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return OS.GetNumBytesInBuffer(); 352c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 353c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 354c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby/// Utility function to write the encoding to an object writer. 355c095793b4ab027181605c79c9808df12afe45d63Kevin Enderbyvoid MCDwarfLineAddr::Write(MCObjectWriter *OW, int64_t LineDelta, 356c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby uint64_t AddrDelta) { 357c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby SmallString<256> Tmp; 358c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_svector_ostream OS(Tmp); 359c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCDwarfLineAddr::Encode(LineDelta, AddrDelta, OS); 360c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OW->WriteBytes(OS.str()); 361c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 362c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 363c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby/// Utility function to emit the encoding to a streamer. 364195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindolavoid MCDwarfLineAddr::Emit(MCStreamer *MCOS, int64_t LineDelta, 365c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby uint64_t AddrDelta) { 366c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby SmallString<256> Tmp; 367c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_svector_ostream OS(Tmp); 368c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCDwarfLineAddr::Encode(LineDelta, AddrDelta, OS); 369c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitBytes(OS.str(), /*AddrSpace=*/0); 370c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 371c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 372c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby/// Utility function to encode a Dwarf pair of LineDelta and AddrDeltas. 373c095793b4ab027181605c79c9808df12afe45d63Kevin Enderbyvoid MCDwarfLineAddr::Encode(int64_t LineDelta, uint64_t AddrDelta, 374c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_ostream &OS) { 375c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby uint64_t Temp, Opcode; 376c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby bool NeedCopy = false; 377c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 378c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Scale the address delta by the minimum instruction length. 379c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby AddrDelta = ScaleAddrDelta(AddrDelta); 380c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 381c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // A LineDelta of INT64_MAX is a signal that this is actually a 382c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // DW_LNE_end_sequence. We cannot use special opcodes here, since we want the 383c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // end_sequence to emit the matrix entry. 384c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (LineDelta == INT64_MAX) { 385c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (AddrDelta == MAX_SPECIAL_ADDR_DELTA) 386c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_const_add_pc); 387c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby else { 388c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_advance_pc); 389c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby SmallString<32> Tmp; 390c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_svector_ostream OSE(Tmp); 391c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCObjectWriter::EncodeULEB128(AddrDelta, OSE); 392c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << OSE.str(); 393c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 394c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_extended_op); 395c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(1); 396c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNE_end_sequence); 397c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return; 398c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 399c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 400c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Bias the line delta by the base. 401c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Temp = LineDelta - DWARF2_LINE_BASE; 402c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 403c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // If the line increment is out of range of a special opcode, we must encode 404c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // it with DW_LNS_advance_line. 405c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (Temp >= DWARF2_LINE_RANGE) { 406c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_advance_line); 407c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby SmallString<32> Tmp; 408c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_svector_ostream OSE(Tmp); 409c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCObjectWriter::EncodeSLEB128(LineDelta, OSE); 410c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << OSE.str(); 411c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 412c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby LineDelta = 0; 413c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Temp = 0 - DWARF2_LINE_BASE; 414c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby NeedCopy = true; 415c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 416c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 417c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Use DW_LNS_copy instead of a "line +0, addr +0" special opcode. 418c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (LineDelta == 0 && AddrDelta == 0) { 419c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_copy); 420c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return; 421c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 422c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 423c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Bias the opcode by the special opcode base. 424c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Temp += DWARF2_LINE_OPCODE_BASE; 425c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 426c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Avoid overflow when addr_delta is large. 427c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (AddrDelta < 256 + MAX_SPECIAL_ADDR_DELTA) { 428c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Try using a special opcode. 429c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Opcode = Temp + AddrDelta * DWARF2_LINE_RANGE; 430c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (Opcode <= 255) { 431c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(Opcode); 432c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return; 433c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 434c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 435c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Try using DW_LNS_const_add_pc followed by special op. 436c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Opcode = Temp + (AddrDelta - MAX_SPECIAL_ADDR_DELTA) * DWARF2_LINE_RANGE; 437c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (Opcode <= 255) { 438c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_const_add_pc); 439c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(Opcode); 440c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return; 441c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 442c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 443c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 444c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Otherwise use DW_LNS_advance_pc. 445c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_advance_pc); 446c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby SmallString<32> Tmp; 447c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_svector_ostream OSE(Tmp); 448c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCObjectWriter::EncodeULEB128(AddrDelta, OSE); 449c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << OSE.str(); 450c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 451c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (NeedCopy) 452c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_copy); 453c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby else 454c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(Temp); 455c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 456c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 4577cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderbyvoid MCDwarfFile::print(raw_ostream &OS) const { 4587cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby OS << '"' << getName() << '"'; 4597cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby} 4607cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby 4617cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderbyvoid MCDwarfFile::dump() const { 4627cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby print(dbgs()); 4637cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby} 464c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 465