1 //===- lib/MC/MCStreamer.cpp - Streaming Machine Code Output --------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "llvm/MC/MCAsmInfo.h"
11 #include "llvm/MC/MCContext.h"
12 #include "llvm/MC/MCStreamer.h"
13 #include "llvm/MC/MCExpr.h"
14 #include "llvm/MC/MCObjectWriter.h"
15 #include "llvm/Support/ErrorHandling.h"
16 #include "llvm/Support/raw_ostream.h"
17 #include "llvm/ADT/SmallString.h"
18 #include "llvm/ADT/Twine.h"
22 MCStreamer::MCStreamer(MCContext &Ctx) : Context(Ctx), CurSection(0),
26 MCStreamer::~MCStreamer() {
29 raw_ostream &MCStreamer::GetCommentOS() {
30 // By default, discard comments.
34 void MCStreamer::EmitDwarfSetLineAddr(int64_t LineDelta,
35 const MCSymbol *Label, int PointerSize) {
36 // emit the sequence to set the address
37 EmitIntValue(dwarf::DW_LNS_extended_op, 1);
38 EmitULEB128IntValue(PointerSize + 1);
39 EmitIntValue(dwarf::DW_LNE_set_address, 1);
40 EmitSymbolValue(Label, PointerSize);
42 // emit the sequence for the LineDelta (from 1) and a zero address delta.
43 MCDwarfLineAddr::Emit(this, LineDelta, 0);
46 /// EmitIntValue - Special case of EmitValue that avoids the client having to
47 /// pass in a MCExpr for constant integers.
48 void MCStreamer::EmitIntValue(uint64_t Value, unsigned Size,
50 assert(Size <= 8 && "Invalid size");
51 assert(!(Size == 1 && (signed)Value > 255) && "Invalid size");
53 // FIXME: Endianness assumption.
54 for (unsigned i = 0; i != Size; ++i)
55 buf[i] = uint8_t(Value >> (i * 8));
56 EmitBytes(StringRef(buf, Size), AddrSpace);
59 /// EmitULEB128Value - Special case of EmitULEB128Value that avoids the
60 /// client having to pass in a MCExpr for constant integers.
61 void MCStreamer::EmitULEB128IntValue(uint64_t Value, unsigned AddrSpace) {
63 raw_svector_ostream OSE(Tmp);
64 MCObjectWriter::EncodeULEB128(Value, OSE);
65 EmitBytes(OSE.str(), AddrSpace);
68 /// EmitSLEB128Value - Special case of EmitSLEB128Value that avoids the
69 /// client having to pass in a MCExpr for constant integers.
70 void MCStreamer::EmitSLEB128IntValue(int64_t Value, unsigned AddrSpace) {
72 raw_svector_ostream OSE(Tmp);
73 MCObjectWriter::EncodeSLEB128(Value, OSE);
74 EmitBytes(OSE.str(), AddrSpace);
77 void MCStreamer::EmitAbsValue(const MCExpr *Value, unsigned Size,
79 if (!getContext().getAsmInfo().needsSetToChangeDiffSize()) {
80 EmitValue(Value, Size, AddrSpace);
83 MCSymbol *ABS = getContext().CreateTempSymbol();
84 EmitAssignment(ABS, Value);
85 EmitSymbolValue(ABS, Size, AddrSpace);
89 void MCStreamer::EmitValue(const MCExpr *Value, unsigned Size,
91 EmitValueImpl(Value, Size, false, AddrSpace);
94 void MCStreamer::EmitPCRelValue(const MCExpr *Value, unsigned Size,
96 EmitValueImpl(Value, Size, true, AddrSpace);
99 void MCStreamer::EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
100 bool isPCRel, unsigned AddrSpace) {
101 EmitValueImpl(MCSymbolRefExpr::Create(Sym, getContext()), Size, isPCRel,
105 void MCStreamer::EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
106 unsigned AddrSpace) {
107 EmitSymbolValue(Sym, Size, false, AddrSpace);
110 void MCStreamer::EmitPCRelSymbolValue(const MCSymbol *Sym, unsigned Size,
111 unsigned AddrSpace) {
112 EmitSymbolValue(Sym, Size, true, AddrSpace);
115 void MCStreamer::EmitGPRel32Value(const MCExpr *Value) {
116 report_fatal_error("unsupported directive in streamer");
119 /// EmitFill - Emit NumBytes bytes worth of the value specified by
120 /// FillValue. This implements directives such as '.space'.
121 void MCStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue,
122 unsigned AddrSpace) {
123 const MCExpr *E = MCConstantExpr::Create(FillValue, getContext());
124 for (uint64_t i = 0, e = NumBytes; i != e; ++i)
125 EmitValue(E, 1, AddrSpace);
128 bool MCStreamer::EmitDwarfFileDirective(unsigned FileNo,
129 StringRef Filename) {
130 return getContext().GetDwarfFile(Filename, FileNo) == 0;
133 void MCStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
134 unsigned Column, unsigned Flags,
136 unsigned Discriminator) {
137 getContext().setCurrentDwarfLoc(FileNo, Line, Column, Flags, Isa,
141 MCDwarfFrameInfo *MCStreamer::getCurrentFrameInfo() {
142 if (FrameInfos.empty())
144 return &FrameInfos.back();
147 void MCStreamer::EnsureValidFrame() {
148 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
149 if (!CurFrame || CurFrame->End)
150 report_fatal_error("No open frame");
153 bool MCStreamer::EmitCFIStartProc() {
154 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
155 if (CurFrame && !CurFrame->End) {
156 report_fatal_error("Starting a frame before finishing the previous one!");
159 MCDwarfFrameInfo Frame = {0, 0, 0, 0};
160 Frame.Begin = getContext().CreateTempSymbol();
161 EmitLabel(Frame.Begin);
162 FrameInfos.push_back(Frame);
166 bool MCStreamer::EmitCFIEndProc() {
168 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
169 CurFrame->End = getContext().CreateTempSymbol();
170 EmitLabel(CurFrame->End);
174 bool MCStreamer::EmitCFIDefCfaOffset(int64_t Offset) {
179 bool MCStreamer::EmitCFIDefCfaRegister(int64_t Register) {
184 bool MCStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) {
189 bool MCStreamer::EmitCFIPersonality(const MCSymbol *Sym) {
191 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
192 CurFrame->Personality = Sym;
196 bool MCStreamer::EmitCFILsda(const MCSymbol *Sym) {
198 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
199 CurFrame->Lsda = Sym;
203 /// EmitRawText - If this file is backed by an assembly streamer, this dumps
204 /// the specified string in the output .s file. This capability is
205 /// indicated by the hasRawTextSupport() predicate.
206 void MCStreamer::EmitRawText(StringRef String) {
207 errs() << "EmitRawText called on an MCStreamer that doesn't support it, "
208 " something must not be fully mc'ized\n";
212 void MCStreamer::EmitRawText(const Twine &T) {
213 SmallString<128> Str;
215 EmitRawText(Str.str());