1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
|
//===- lib/MC/MCWasmStreamer.cpp - Wasm Object Output ---------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file assembles .s files and emits Wasm .o object files.
//
//===----------------------------------------------------------------------===//
#include "llvm/MC/MCWasmStreamer.h"
#include "llvm/MC/MCAsmBackend.h"
#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCFixup.h"
#include "llvm/MC/MCObjectStreamer.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCSectionWasm.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/MC/MCSymbolWasm.h"
#include "llvm/MC/TargetRegistry.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/ErrorHandling.h"
namespace llvm {
class MCContext;
class MCStreamer;
class MCSubtargetInfo;
} // namespace llvm
using namespace llvm;
MCWasmStreamer::~MCWasmStreamer() = default; // anchor.
void MCWasmStreamer::emitLabel(MCSymbol *S, SMLoc Loc) {
auto *Symbol = cast<MCSymbolWasm>(S);
MCObjectStreamer::emitLabel(Symbol, Loc);
const MCSectionWasm &Section =
static_cast<const MCSectionWasm &>(*getCurrentSectionOnly());
if (Section.getSegmentFlags() & wasm::WASM_SEG_FLAG_TLS)
Symbol->setTLS();
}
void MCWasmStreamer::emitLabelAtPos(MCSymbol *S, SMLoc Loc, MCFragment &F,
uint64_t Offset) {
auto *Symbol = cast<MCSymbolWasm>(S);
MCObjectStreamer::emitLabelAtPos(Symbol, Loc, F, Offset);
const MCSectionWasm &Section =
static_cast<const MCSectionWasm &>(*getCurrentSectionOnly());
if (Section.getSegmentFlags() & wasm::WASM_SEG_FLAG_TLS)
Symbol->setTLS();
}
void MCWasmStreamer::changeSection(MCSection *Section, uint32_t Subsection) {
MCAssembler &Asm = getAssembler();
auto *SectionWasm = cast<MCSectionWasm>(Section);
const MCSymbol *Grp = SectionWasm->getGroup();
if (Grp)
Asm.registerSymbol(*Grp);
this->MCObjectStreamer::changeSection(Section, Subsection);
Asm.registerSymbol(*Section->getBeginSymbol());
}
bool MCWasmStreamer::emitSymbolAttribute(MCSymbol *S, MCSymbolAttr Attribute) {
assert(Attribute != MCSA_IndirectSymbol && "indirect symbols not supported");
auto *Symbol = cast<MCSymbolWasm>(S);
// Adding a symbol attribute always introduces the symbol; note that an
// important side effect of calling registerSymbol here is to register the
// symbol with the assembler.
getAssembler().registerSymbol(*Symbol);
switch (Attribute) {
case MCSA_LazyReference:
case MCSA_Reference:
case MCSA_SymbolResolver:
case MCSA_PrivateExtern:
case MCSA_WeakDefinition:
case MCSA_WeakDefAutoPrivate:
case MCSA_Invalid:
case MCSA_IndirectSymbol:
case MCSA_Protected:
case MCSA_Exported:
return false;
case MCSA_Hidden:
Symbol->setHidden(true);
break;
case MCSA_Weak:
case MCSA_WeakReference:
Symbol->setWeak(true);
Symbol->setExternal(true);
break;
case MCSA_Global:
Symbol->setExternal(true);
break;
case MCSA_ELF_TypeFunction:
Symbol->setType(wasm::WASM_SYMBOL_TYPE_FUNCTION);
break;
case MCSA_ELF_TypeTLS:
Symbol->setTLS();
break;
case MCSA_ELF_TypeObject:
case MCSA_Cold:
break;
case MCSA_NoDeadStrip:
Symbol->setNoStrip();
break;
default:
// unrecognized directive
llvm_unreachable("unexpected MCSymbolAttr");
return false;
}
return true;
}
void MCWasmStreamer::emitCommonSymbol(MCSymbol *S, uint64_t Size,
Align ByteAlignment) {
llvm_unreachable("Common symbols are not yet implemented for Wasm");
}
void MCWasmStreamer::emitELFSize(MCSymbol *Symbol, const MCExpr *Value) {
cast<MCSymbolWasm>(Symbol)->setSize(Value);
}
void MCWasmStreamer::emitLocalCommonSymbol(MCSymbol *S, uint64_t Size,
Align ByteAlignment) {
llvm_unreachable("Local common symbols are not yet implemented for Wasm");
}
void MCWasmStreamer::emitIdent(StringRef IdentString) {
// TODO(sbc): Add the ident section once we support mergable strings
// sections in the object format
}
void MCWasmStreamer::finishImpl() {
emitFrames(nullptr);
this->MCObjectStreamer::finishImpl();
}
MCStreamer *llvm::createWasmStreamer(MCContext &Context,
std::unique_ptr<MCAsmBackend> &&MAB,
std::unique_ptr<MCObjectWriter> &&OW,
std::unique_ptr<MCCodeEmitter> &&CE) {
MCWasmStreamer *S =
new MCWasmStreamer(Context, std::move(MAB), std::move(OW), std::move(CE));
return S;
}
|
