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);
88 void MCStreamer::EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
90 EmitValue(MCSymbolRefExpr::Create(Sym, getContext()), Size, AddrSpace);
93 void MCStreamer::EmitGPRel32Value(const MCExpr *Value) {
94 report_fatal_error("unsupported directive in streamer");
97 /// EmitFill - Emit NumBytes bytes worth of the value specified by
98 /// FillValue. This implements directives such as '.space'.
99 void MCStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue,
100 unsigned AddrSpace) {
101 const MCExpr *E = MCConstantExpr::Create(FillValue, getContext());
102 for (uint64_t i = 0, e = NumBytes; i != e; ++i)
103 EmitValue(E, 1, AddrSpace);
106 bool MCStreamer::EmitDwarfFileDirective(unsigned FileNo,
107 StringRef Filename) {
108 return getContext().GetDwarfFile(Filename, FileNo) == 0;
111 void MCStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
112 unsigned Column, unsigned Flags,
114 unsigned Discriminator) {
115 getContext().setCurrentDwarfLoc(FileNo, Line, Column, Flags, Isa,
119 bool MCStreamer::EmitCFIStartProc() {
123 bool MCStreamer::EmitCFIEndProc() {
127 bool MCStreamer::EmitCFIDefCfaOffset(int64_t Offset) {
131 bool MCStreamer::EmitCFIDefCfaRegister(int64_t Register) {
135 bool MCStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) {
139 bool MCStreamer::EmitCFIPersonality(const MCSymbol *Sym) {
143 bool MCStreamer::EmitCFILsda(const MCSymbol *Sym) {
147 /// EmitRawText - If this file is backed by an assembly streamer, this dumps
148 /// the specified string in the output .s file. This capability is
149 /// indicated by the hasRawTextSupport() predicate.
150 void MCStreamer::EmitRawText(StringRef String) {
151 errs() << "EmitRawText called on an MCStreamer that doesn't support it, "
152 " something must not be fully mc'ized\n";
156 void MCStreamer::EmitRawText(const Twine &T) {
157 SmallString<128> Str;
159 EmitRawText(Str.str());