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((isUIntN(8 * Size, Value) || isIntN(8 * Size, Value)) &&
54 // FIXME: Endianness assumption.
55 for (unsigned i = 0; i != Size; ++i)
56 buf[i] = uint8_t(Value >> (i * 8));
57 EmitBytes(StringRef(buf, Size), AddrSpace);
60 /// EmitULEB128Value - Special case of EmitULEB128Value that avoids the
61 /// client having to pass in a MCExpr for constant integers.
62 void MCStreamer::EmitULEB128IntValue(uint64_t Value, unsigned AddrSpace) {
64 raw_svector_ostream OSE(Tmp);
65 MCObjectWriter::EncodeULEB128(Value, OSE);
66 EmitBytes(OSE.str(), AddrSpace);
69 /// EmitSLEB128Value - Special case of EmitSLEB128Value that avoids the
70 /// client having to pass in a MCExpr for constant integers.
71 void MCStreamer::EmitSLEB128IntValue(int64_t Value, unsigned AddrSpace) {
73 raw_svector_ostream OSE(Tmp);
74 MCObjectWriter::EncodeSLEB128(Value, OSE);
75 EmitBytes(OSE.str(), AddrSpace);
78 void MCStreamer::EmitAbsValue(const MCExpr *Value, unsigned Size,
80 if (!getContext().getAsmInfo().needsSetToChangeDiffSize()) {
81 EmitValue(Value, Size, AddrSpace);
84 MCSymbol *ABS = getContext().CreateTempSymbol();
85 EmitAssignment(ABS, Value);
86 EmitSymbolValue(ABS, Size, AddrSpace);
90 void MCStreamer::EmitValue(const MCExpr *Value, unsigned Size,
92 EmitValueImpl(Value, Size, false, AddrSpace);
95 void MCStreamer::EmitPCRelValue(const MCExpr *Value, unsigned Size,
97 EmitValueImpl(Value, Size, true, AddrSpace);
100 void MCStreamer::EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
101 bool isPCRel, unsigned AddrSpace) {
102 EmitValueImpl(MCSymbolRefExpr::Create(Sym, getContext()), Size, isPCRel,
106 void MCStreamer::EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
107 unsigned AddrSpace) {
108 EmitSymbolValue(Sym, Size, false, AddrSpace);
111 void MCStreamer::EmitPCRelSymbolValue(const MCSymbol *Sym, unsigned Size,
112 unsigned AddrSpace) {
113 EmitSymbolValue(Sym, Size, true, AddrSpace);
116 void MCStreamer::EmitGPRel32Value(const MCExpr *Value) {
117 report_fatal_error("unsupported directive in streamer");
120 /// EmitFill - Emit NumBytes bytes worth of the value specified by
121 /// FillValue. This implements directives such as '.space'.
122 void MCStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue,
123 unsigned AddrSpace) {
124 const MCExpr *E = MCConstantExpr::Create(FillValue, getContext());
125 for (uint64_t i = 0, e = NumBytes; i != e; ++i)
126 EmitValue(E, 1, AddrSpace);
129 bool MCStreamer::EmitDwarfFileDirective(unsigned FileNo,
130 StringRef Filename) {
131 return getContext().GetDwarfFile(Filename, FileNo) == 0;
134 void MCStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
135 unsigned Column, unsigned Flags,
137 unsigned Discriminator) {
138 getContext().setCurrentDwarfLoc(FileNo, Line, Column, Flags, Isa,
142 MCDwarfFrameInfo *MCStreamer::getCurrentFrameInfo() {
143 if (FrameInfos.empty())
145 return &FrameInfos.back();
148 void MCStreamer::EnsureValidFrame() {
149 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
150 if (!CurFrame || CurFrame->End)
151 report_fatal_error("No open frame");
154 bool MCStreamer::EmitCFIStartProc() {
155 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
156 if (CurFrame && !CurFrame->End) {
157 report_fatal_error("Starting a frame before finishing the previous one!");
160 MCDwarfFrameInfo Frame = {0, 0, 0, 0};
161 Frame.Begin = getContext().CreateTempSymbol();
162 EmitLabel(Frame.Begin);
163 FrameInfos.push_back(Frame);
167 bool MCStreamer::EmitCFIEndProc() {
169 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
170 CurFrame->End = getContext().CreateTempSymbol();
171 EmitLabel(CurFrame->End);
175 bool MCStreamer::EmitCFIDefCfaOffset(int64_t Offset) {
180 bool MCStreamer::EmitCFIDefCfaRegister(int64_t Register) {
185 bool MCStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) {
190 bool MCStreamer::EmitCFIPersonality(const MCSymbol *Sym) {
192 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
193 CurFrame->Personality = Sym;
197 bool MCStreamer::EmitCFILsda(const MCSymbol *Sym) {
199 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
200 CurFrame->Lsda = Sym;
204 /// EmitRawText - If this file is backed by an assembly streamer, this dumps
205 /// the specified string in the output .s file. This capability is
206 /// indicated by the hasRawTextSupport() predicate.
207 void MCStreamer::EmitRawText(StringRef String) {
208 errs() << "EmitRawText called on an MCStreamer that doesn't support it, "
209 " something must not be fully mc'ized\n";
213 void MCStreamer::EmitRawText(const Twine &T) {
214 SmallString<128> Str;
216 EmitRawText(Str.str());