MCDwarf.cpp revision ad8aaa069cfdb3bdc32b1becc8881f67b5272e14
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" 12ad8aaa069cfdb3bdc32b1becc8881f67b5272e14Rafael Espindola#include "llvm/MC/MCStreamer.h" 13c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/MC/MCSymbol.h" 14c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/MC/MCExpr.h" 15c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/MC/MCContext.h" 16c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/MC/MCObjectWriter.h" 17c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/ADT/SmallString.h" 187cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby#include "llvm/Support/Debug.h" 197cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby#include "llvm/Support/raw_ostream.h" 20c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#include "llvm/Target/TargetAsmBackend.h" 217cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderbyusing namespace llvm; 227cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby 23c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// Given a special op, return the address skip amount (in units of 24c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// DWARF2_LINE_MIN_INSN_LENGTH. 25c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#define SPECIAL_ADDR(op) (((op) - DWARF2_LINE_OPCODE_BASE)/DWARF2_LINE_RANGE) 26c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 27c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// The maximum address skip amount that can be encoded with a special op. 28c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#define MAX_SPECIAL_ADDR_DELTA SPECIAL_ADDR(255) 29c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 30c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// First special line opcode - leave room for the standard opcodes. 31c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// Note: If you want to change this, you'll have to update the 32c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// "standard_opcode_lengths" table that is emitted in DwarfFileTable::Emit(). 33c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#define DWARF2_LINE_OPCODE_BASE 13 34c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 35c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// Minimum line offset in a special line info. opcode. This value 36c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// was chosen to give a reasonable range of values. 37c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby#define DWARF2_LINE_BASE -5 38c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 39c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// Range of line offsets in a special line info. opcode. 40c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby# define DWARF2_LINE_RANGE 14 41c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 42c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// Define the architecture-dependent minimum instruction length (in bytes). 43c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// This value should be rather too small than too big. 44c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby# define DWARF2_LINE_MIN_INSN_LENGTH 1 45c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 46c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// Note: when DWARF2_LINE_MIN_INSN_LENGTH == 1 which is the current setting, 47c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// this routine is a nop and will be optimized away. 48c095793b4ab027181605c79c9808df12afe45d63Kevin Enderbystatic inline uint64_t ScaleAddrDelta(uint64_t AddrDelta) 49c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby{ 50c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (DWARF2_LINE_MIN_INSN_LENGTH == 1) 51c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return AddrDelta; 52c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (AddrDelta % DWARF2_LINE_MIN_INSN_LENGTH != 0) { 53c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // TODO: report this error, but really only once. 54c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby ; 55c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 56c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return AddrDelta / DWARF2_LINE_MIN_INSN_LENGTH; 57c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 58c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 59c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 60c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// This is called when an instruction is assembled into the specified section 61c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// and if there is information from the last .loc directive that has yet to have 62c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// a line entry made for it is made. 63c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 64195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindolavoid MCLineEntry::Make(MCStreamer *MCOS, const MCSection *Section) { 65c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (!MCOS->getContext().getDwarfLocSeen()) 66c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return; 67c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 68c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a symbol at in the current section for use in the line entry. 69c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *LineSym = MCOS->getContext().CreateTempSymbol(); 70c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Set the value of the symbol to use for the MCLineEntry. 71c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitLabel(LineSym); 72c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 73c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Get the current .loc info saved in the context. 74c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCDwarfLoc &DwarfLoc = MCOS->getContext().getCurrentDwarfLoc(); 75c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 76c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a (local) line entry with the symbol and the current .loc info. 77c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCLineEntry LineEntry(LineSym, DwarfLoc); 78c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 79c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // clear DwarfLocSeen saying the current .loc info is now used. 803f55c24df9527de345f6cc960944840a7a101c6aKevin Enderby MCOS->getContext().ClearDwarfLocSeen(); 81c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 82c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Get the MCLineSection for this section, if one does not exist for this 83c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // section create it. 8417fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola const DenseMap<const MCSection *, MCLineSection *> &MCLineSections = 85c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->getContext().getMCLineSections(); 8617fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola MCLineSection *LineSection = MCLineSections.lookup(Section); 87c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (!LineSection) { 88c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a new MCLineSection. This will be deleted after the dwarf line 89c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // table is created using it by iterating through the MCLineSections 90c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // DenseMap. 91c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby LineSection = new MCLineSection; 92c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Save a pointer to the new LineSection into the MCLineSections DenseMap. 9317fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola MCOS->getContext().addMCLineSection(Section, LineSection); 94c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 95c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 96c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Add the line entry to this section's entries. 97c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby LineSection->addLineEntry(LineEntry); 98c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 99c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 100c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 101c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// This helper routine returns an expression of End - Start + IntVal . 102c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 103195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindolastatic inline const MCExpr *MakeStartMinusEndExpr(MCStreamer *MCOS, 104c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *Start, 105c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *End, int IntVal) { 106c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None; 107c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCExpr *Res = 108c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbolRefExpr::Create(End, Variant, MCOS->getContext()); 109c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCExpr *RHS = 110c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbolRefExpr::Create(Start, Variant, MCOS->getContext()); 111c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCExpr *Res1 = 112c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCBinaryExpr::Create(MCBinaryExpr::Sub, Res, RHS, MCOS->getContext()); 113c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCExpr *Res2 = 114c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCConstantExpr::Create(IntVal, MCOS->getContext()); 115c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCExpr *Res3 = 116c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCBinaryExpr::Create(MCBinaryExpr::Sub, Res1, Res2, MCOS->getContext()); 117c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return Res3; 118c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 119c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 120c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 121c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// This emits an "absolute" address used in the start of a dwarf line number 122c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// table. This will result in a relocatation entry for the address. 123c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 124195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindolastatic inline void EmitDwarfSetAddress(MCStreamer *MCOS, 125195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola MCSymbol *Symbol, 126195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola int PointerSize) { 127c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_extended_op, 1); 128c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 129195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola MCOS->EmitULEB128IntValue(PointerSize + 1); 130c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 131c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNE_set_address, 1); 132195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola MCOS->EmitSymbolValue(Symbol, PointerSize); 133c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 134c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 135c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 136c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// This emits the Dwarf line table for the specified section from the entries 137c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// in the LineSection. 138c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 139195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindolastatic inline void EmitDwarfLineTable(MCStreamer *MCOS, 140c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCSection *Section, 14117fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola const MCLineSection *LineSection, 142195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola const MCSection *DwarfLineSection, 143195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola MCSectionData *DLS, 144195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola int PointerSize) { 145c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby unsigned FileNum = 1; 146c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby unsigned LastLine = 1; 147c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby unsigned Column = 0; 148c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby unsigned Flags = DWARF2_LINE_DEFAULT_IS_STMT ? DWARF2_FLAG_IS_STMT : 0; 149c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby unsigned Isa = 0; 150c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *LastLabel = NULL; 151c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 152c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Loop through each MCLineEntry and encode the dwarf line number table. 15317fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola for (MCLineSection::const_iterator 154c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby it = LineSection->getMCLineEntries()->begin(), 155c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby ie = LineSection->getMCLineEntries()->end(); it != ie; ++it) { 156c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 157c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (FileNum != it->getFileNum()) { 158c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby FileNum = it->getFileNum(); 159c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_set_file, 1); 1603ff57094a7d176a759ddb1e1668489d89064f56cRafael Espindola MCOS->EmitULEB128IntValue(FileNum); 161c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 162c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (Column != it->getColumn()) { 163c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Column = it->getColumn(); 164c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_set_column, 1); 1653ff57094a7d176a759ddb1e1668489d89064f56cRafael Espindola MCOS->EmitULEB128IntValue(Column); 166c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 167c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (Isa != it->getIsa()) { 168c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Isa = it->getIsa(); 169c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_set_isa, 1); 1703ff57094a7d176a759ddb1e1668489d89064f56cRafael Espindola MCOS->EmitULEB128IntValue(Isa); 171c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 172c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if ((it->getFlags() ^ Flags) & DWARF2_FLAG_IS_STMT) { 173c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Flags = it->getFlags(); 174c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_negate_stmt, 1); 175c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 176c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (it->getFlags() & DWARF2_FLAG_BASIC_BLOCK) 177c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_set_basic_block, 1); 178c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (it->getFlags() & DWARF2_FLAG_PROLOGUE_END) 179c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_set_prologue_end, 1); 180c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (it->getFlags() & DWARF2_FLAG_EPILOGUE_BEGIN) 181c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(dwarf::DW_LNS_set_epilogue_begin, 1); 182c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 18364185cc6090f695c4f97c51cf2adc731f56d1a20Rafael Espindola int64_t LineDelta = static_cast<int64_t>(it->getLine()) - LastLine; 184c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *Label = it->getLabel(); 185c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 186c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // At this point we want to emit/create the sequence to encode the delta in 187c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // line numbers and the increment of the address from the previous Label 188c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // and the current Label. 189195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola if (LastLabel == NULL || DLS == NULL) { 190c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // emit the sequence to set the address 191195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola EmitDwarfSetAddress(MCOS, Label, PointerSize); 192c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // emit the sequence for the LineDelta (from 1) and a zero address delta. 193c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCDwarfLineAddr::Emit(MCOS, LineDelta, 0); 194c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 195c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby else { 196c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create an expression for the address delta from the LastLabel and 197c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // this Label (plus 0). 198c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const MCExpr *AddrDelta = MakeStartMinusEndExpr(MCOS, LastLabel, Label,0); 199c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a Dwarf Line fragment for the LineDelta and AddrDelta. 200195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola new MCDwarfLineAddrFragment(LineDelta, *AddrDelta, DLS); 201c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 202c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 203c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby LastLine = it->getLine(); 204c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby LastLabel = Label; 205c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 206c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 207c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Emit a DW_LNE_end_sequence for the end of the section. 208c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Using the pointer Section create a temporary label at the end of the 209c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // section and use that and the LastLabel to compute the address delta 210c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // and use INT64_MAX as the line delta which is the signal that this is 211c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // actually a DW_LNE_end_sequence. 212c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 213c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Switch to the section to be able to create a symbol at its end. 214c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->SwitchSection(Section); 215c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a symbol at the end of the section. 216c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *SectionEnd = MCOS->getContext().CreateTempSymbol(); 217c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Set the value of the symbol, as we are at the end of the section. 218c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitLabel(SectionEnd); 219c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 220c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Switch back the the dwarf line section. 221c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->SwitchSection(DwarfLineSection); 222195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola 223195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola if (DLS == NULL) { 224195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola // emit the sequence to set the address 225195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola EmitDwarfSetAddress(MCOS, SectionEnd, PointerSize); 226195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola // emit the sequence for the LineDelta (from 1) and a zero address delta. 227195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola MCDwarfLineAddr::Emit(MCOS, INT64_MAX, 0); 228195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola } else { 229195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola // Create an expression for the address delta from the LastLabel and this 230195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola // SectionEnd label. 231195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola const MCExpr *AddrDelta = MakeStartMinusEndExpr(MCOS, LastLabel, SectionEnd, 232195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola 0); 233195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola // Create a Dwarf Line fragment for the LineDelta and AddrDelta. 234195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola new MCDwarfLineAddrFragment(INT64_MAX, *AddrDelta, DLS); 235195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola } 236c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 237c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 238c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 239c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// This emits the Dwarf file and the line tables. 240c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby// 241195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindolavoid MCDwarfFileTable::Emit(MCStreamer *MCOS, 242195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola const MCSection *DwarfLineSection, 243195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola MCSectionData *DLS, 244195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola int PointerSize) { 245c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Switch to the section where the table will be emitted into. 246c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->SwitchSection(DwarfLineSection); 247c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 248c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a symbol at the beginning of this section. 249c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *LineStartSym = MCOS->getContext().CreateTempSymbol(); 250c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Set the value of the symbol, as we are at the start of the section. 251c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitLabel(LineStartSym); 252c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 253c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a symbol for the end of the section (to be set when we get there). 254c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *LineEndSym = MCOS->getContext().CreateTempSymbol(); 255c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 256c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // The first 4 bytes is the total length of the information for this 257c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // compilation unit (not including these 4 bytes for the length). 258c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitValue(MakeStartMinusEndExpr(MCOS, LineStartSym, LineEndSym, 4), 259c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 4, 0); 260c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 261c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Next 2 bytes is the Version, which is Dwarf 2. 262c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(2, 2); 263c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 264c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Create a symbol for the end of the prologue (to be set when we get there). 265c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCSymbol *ProEndSym = MCOS->getContext().CreateTempSymbol(); // Lprologue_end 266c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 267c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Length of the prologue, is the next 4 bytes. Which is the start of the 268c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // section to the end of the prologue. Not including the 4 bytes for the 269c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // total length, the 2 bytes for the version, and these 4 bytes for the 270c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // length of the prologue. 271c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitValue(MakeStartMinusEndExpr(MCOS, LineStartSym, ProEndSym, 272c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby (4 + 2 + 4)), 273c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 4, 0); 274c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 275c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Parameters of the state machine, are next. 276c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(DWARF2_LINE_MIN_INSN_LENGTH, 1); 277c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(DWARF2_LINE_DEFAULT_IS_STMT, 1); 278c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(DWARF2_LINE_BASE, 1); 279c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(DWARF2_LINE_RANGE, 1); 280c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(DWARF2_LINE_OPCODE_BASE, 1); 281c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 282c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Standard opcode lengths 283c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // length of DW_LNS_copy 284c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(1, 1); // length of DW_LNS_advance_pc 285c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(1, 1); // length of DW_LNS_advance_line 286c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(1, 1); // length of DW_LNS_set_file 287c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(1, 1); // length of DW_LNS_set_column 288c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // length of DW_LNS_negate_stmt 289c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // length of DW_LNS_set_basic_block 290c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // length of DW_LNS_const_add_pc 291c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(1, 1); // length of DW_LNS_fixed_advance_pc 292c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // length of DW_LNS_set_prologue_end 293c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // length of DW_LNS_set_epilogue_begin 294c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(1, 1); // DW_LNS_set_isa 295c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 296c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Put out the directory and file tables. 297c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 298c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // First the directory table. 299c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const std::vector<StringRef> &MCDwarfDirs = 300c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->getContext().getMCDwarfDirs(); 301c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby for (unsigned i = 0; i < MCDwarfDirs.size(); i++) { 302c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitBytes(MCDwarfDirs[i], 0); // the DirectoryName 303c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitBytes(StringRef("\0", 1), 0); // the null term. of the string 304c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 305c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // Terminate the directory list 306c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 307c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Second the file table. 308c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby const std::vector<MCDwarfFile *> &MCDwarfFiles = 309c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->getContext().getMCDwarfFiles(); 310c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby for (unsigned i = 1; i < MCDwarfFiles.size(); i++) { 311c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitBytes(MCDwarfFiles[i]->getName(), 0); // FileName 312c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitBytes(StringRef("\0", 1), 0); // the null term. of the string 3133ff57094a7d176a759ddb1e1668489d89064f56cRafael Espindola // the Directory num 3143ff57094a7d176a759ddb1e1668489d89064f56cRafael Espindola MCOS->EmitULEB128IntValue(MCDwarfFiles[i]->getDirIndex()); 315c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // last modification timestamp (always 0) 316c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // filesize (always 0) 317c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 318c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitIntValue(0, 1); // Terminate the file list 319c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 320c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // This is the end of the prologue, so set the value of the symbol at the 321c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // end of the prologue (that was used in a previous expression). 322c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitLabel(ProEndSym); 323c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 324c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Put out the line tables. 32517fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola const DenseMap<const MCSection *, MCLineSection *> &MCLineSections = 326c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->getContext().getMCLineSections(); 32717fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola const std::vector<const MCSection *> &MCLineSectionOrder = 32817fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola MCOS->getContext().getMCLineSectionOrder(); 32917fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola for (std::vector<const MCSection*>::const_iterator it = 33017fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola MCLineSectionOrder.begin(), ie = MCLineSectionOrder.end(); it != ie; 33117fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola ++it) { 33217fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola const MCSection *Sec = *it; 33317fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola const MCLineSection *Line = MCLineSections.lookup(Sec); 33417fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola EmitDwarfLineTable(MCOS, Sec, Line, DwarfLineSection, DLS, 335195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindola PointerSize); 336c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 337c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Now delete the MCLineSections that were created in MCLineEntry::Make() 338c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // and used to emit the line table. 33917fd7bda5ac08f873c063c64e1456f8960a0c765Rafael Espindola delete Line; 340c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 341c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 342c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // This is the end of the section, so set the value of the symbol at the end 343c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // of this section (that was used in a previous expression). 344c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitLabel(LineEndSym); 345c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 346c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 347c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby/// Utility function to compute the size of the encoding. 348c095793b4ab027181605c79c9808df12afe45d63Kevin Enderbyuint64_t MCDwarfLineAddr::ComputeSize(int64_t LineDelta, uint64_t AddrDelta) { 349c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby SmallString<256> Tmp; 350c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_svector_ostream OS(Tmp); 351c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCDwarfLineAddr::Encode(LineDelta, AddrDelta, OS); 352c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return OS.GetNumBytesInBuffer(); 353c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 354c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 355c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby/// Utility function to write the encoding to an object writer. 356c095793b4ab027181605c79c9808df12afe45d63Kevin Enderbyvoid MCDwarfLineAddr::Write(MCObjectWriter *OW, int64_t LineDelta, 357c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby uint64_t AddrDelta) { 358c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby SmallString<256> Tmp; 359c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_svector_ostream OS(Tmp); 360c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCDwarfLineAddr::Encode(LineDelta, AddrDelta, OS); 361c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OW->WriteBytes(OS.str()); 362c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 363c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 364c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby/// Utility function to emit the encoding to a streamer. 365195a0ce484cd12a5adae9184188f6d0fb52b84c0Rafael Espindolavoid MCDwarfLineAddr::Emit(MCStreamer *MCOS, int64_t LineDelta, 366c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby uint64_t AddrDelta) { 367c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby SmallString<256> Tmp; 368c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_svector_ostream OS(Tmp); 369c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCDwarfLineAddr::Encode(LineDelta, AddrDelta, OS); 370c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCOS->EmitBytes(OS.str(), /*AddrSpace=*/0); 371c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 372c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 373c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby/// Utility function to encode a Dwarf pair of LineDelta and AddrDeltas. 374c095793b4ab027181605c79c9808df12afe45d63Kevin Enderbyvoid MCDwarfLineAddr::Encode(int64_t LineDelta, uint64_t AddrDelta, 375c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_ostream &OS) { 376c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby uint64_t Temp, Opcode; 377c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby bool NeedCopy = false; 378c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 379c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Scale the address delta by the minimum instruction length. 380c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby AddrDelta = ScaleAddrDelta(AddrDelta); 381c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 382c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // A LineDelta of INT64_MAX is a signal that this is actually a 383c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // DW_LNE_end_sequence. We cannot use special opcodes here, since we want the 384c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // end_sequence to emit the matrix entry. 385c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (LineDelta == INT64_MAX) { 386c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (AddrDelta == MAX_SPECIAL_ADDR_DELTA) 387c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_const_add_pc); 388c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby else { 389c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_advance_pc); 390c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby SmallString<32> Tmp; 391c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_svector_ostream OSE(Tmp); 392c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCObjectWriter::EncodeULEB128(AddrDelta, OSE); 393c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << OSE.str(); 394c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 395c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_extended_op); 396c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(1); 397c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNE_end_sequence); 398c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return; 399c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 400c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 401c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Bias the line delta by the base. 402c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Temp = LineDelta - DWARF2_LINE_BASE; 403c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 404c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // If the line increment is out of range of a special opcode, we must encode 405c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // it with DW_LNS_advance_line. 406c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (Temp >= DWARF2_LINE_RANGE) { 407c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_advance_line); 408c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby SmallString<32> Tmp; 409c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_svector_ostream OSE(Tmp); 410c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCObjectWriter::EncodeSLEB128(LineDelta, OSE); 411c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << OSE.str(); 412c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 413c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby LineDelta = 0; 414c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Temp = 0 - DWARF2_LINE_BASE; 415c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby NeedCopy = true; 416c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 417c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 418c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Use DW_LNS_copy instead of a "line +0, addr +0" special opcode. 419c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (LineDelta == 0 && AddrDelta == 0) { 420c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_copy); 421c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return; 422c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 423c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 424c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Bias the opcode by the special opcode base. 425c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Temp += DWARF2_LINE_OPCODE_BASE; 426c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 427c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Avoid overflow when addr_delta is large. 428c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (AddrDelta < 256 + MAX_SPECIAL_ADDR_DELTA) { 429c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Try using a special opcode. 430c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Opcode = Temp + AddrDelta * DWARF2_LINE_RANGE; 431c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (Opcode <= 255) { 432c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(Opcode); 433c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return; 434c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 435c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 436c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Try using DW_LNS_const_add_pc followed by special op. 437c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby Opcode = Temp + (AddrDelta - MAX_SPECIAL_ADDR_DELTA) * DWARF2_LINE_RANGE; 438c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (Opcode <= 255) { 439c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_const_add_pc); 440c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(Opcode); 441c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby return; 442c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 443c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby } 444c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 445c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby // Otherwise use DW_LNS_advance_pc. 446c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_advance_pc); 447c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby SmallString<32> Tmp; 448c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby raw_svector_ostream OSE(Tmp); 449c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby MCObjectWriter::EncodeULEB128(AddrDelta, OSE); 450c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << OSE.str(); 451c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 452c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby if (NeedCopy) 453c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(dwarf::DW_LNS_copy); 454c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby else 455c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby OS << char(Temp); 456c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby} 457c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 4587cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderbyvoid MCDwarfFile::print(raw_ostream &OS) const { 4597cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby OS << '"' << getName() << '"'; 4607cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby} 4617cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby 4627cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderbyvoid MCDwarfFile::dump() const { 4637cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby print(dbgs()); 4647cbf73a73f296167b6e978dbd919ed249e88eeb5Kevin Enderby} 465c095793b4ab027181605c79c9808df12afe45d63Kevin Enderby 466