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
|
//===-- lib/MC/XCOFFObjectWriter.cpp - XCOFF file writer ------------------===//
//
// 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 implements XCOFF object file writer information.
//
//===----------------------------------------------------------------------===//
#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCObjectWriter.h"
#include "llvm/MC/MCValue.h"
#include "llvm/MC/MCXCOFFObjectWriter.h"
using namespace llvm;
namespace {
class XCOFFObjectWriter : public MCObjectWriter {
support::endian::Writer W;
std::unique_ptr<MCXCOFFObjectTargetWriter> TargetObjectWriter;
void executePostLayoutBinding(MCAssembler &, const MCAsmLayout &) override;
void recordRelocation(MCAssembler &, const MCAsmLayout &, const MCFragment *,
const MCFixup &, MCValue, uint64_t &) override;
uint64_t writeObject(MCAssembler &, const MCAsmLayout &) override;
public:
XCOFFObjectWriter(std::unique_ptr<MCXCOFFObjectTargetWriter> MOTW,
raw_pwrite_stream &OS);
};
XCOFFObjectWriter::XCOFFObjectWriter(
std::unique_ptr<MCXCOFFObjectTargetWriter> MOTW, raw_pwrite_stream &OS)
: W(OS, support::big), TargetObjectWriter(std::move(MOTW)) {}
void XCOFFObjectWriter::executePostLayoutBinding(MCAssembler &,
const MCAsmLayout &) {
// TODO Implement once we have sections and symbols to handle.
}
void XCOFFObjectWriter::recordRelocation(MCAssembler &, const MCAsmLayout &,
const MCFragment *, const MCFixup &,
MCValue, uint64_t &) {
report_fatal_error("XCOFF relocations not supported.");
}
uint64_t XCOFFObjectWriter::writeObject(MCAssembler &Asm, const MCAsmLayout &) {
// We always emit a timestamp of 0 for reproducibility, so ensure incremental
// linking is not enabled, in case, like with Windows COFF, such a timestamp
// is incompatible with incremental linking of XCOFF.
if (Asm.isIncrementalLinkerCompatible())
report_fatal_error("Incremental linking not supported for XCOFF.");
if (TargetObjectWriter->is64Bit())
report_fatal_error("64-bit XCOFF object files are not supported yet.");
uint64_t StartOffset = W.OS.tell();
// TODO FIXME Assign section numbers/finalize sections.
// TODO FIXME Finalize symbols.
// Magic.
W.write<uint16_t>(0x01df);
// Number of sections.
W.write<uint16_t>(0);
// Timestamp field. For reproducible output we write a 0, which represents no
// timestamp.
W.write<int32_t>(0);
// Byte Offset to the start of the symbol table.
W.write<uint32_t>(0);
// Number of entries in the symbol table.
W.write<int32_t>(0);
// Size of the optional header.
W.write<uint16_t>(0);
// Flags.
W.write<uint16_t>(0);
return W.OS.tell() - StartOffset;
}
} // end anonymous namespace
std::unique_ptr<MCObjectWriter>
llvm::createXCOFFObjectWriter(std::unique_ptr<MCXCOFFObjectTargetWriter> MOTW,
raw_pwrite_stream &OS) {
return std::make_unique<XCOFFObjectWriter>(std::move(MOTW), OS);
}
|
