1//===-- LoongArchELFStreamer.cpp - LoongArch ELF Target Streamer Methods --===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file provides LoongArch specific target streamer methods.
10//
11//===----------------------------------------------------------------------===//
12
13#include "LoongArchELFStreamer.h"
14#include "LoongArchAsmBackend.h"
15#include "LoongArchBaseInfo.h"
16#include "llvm/BinaryFormat/ELF.h"
17#include "llvm/MC/MCAssembler.h"
18#include "llvm/MC/MCCodeEmitter.h"
19#include "llvm/MC/MCELFObjectWriter.h"
20#include "llvm/MC/MCSection.h"
21
22using namespace llvm;
23
24// This part is for ELF object output.
25LoongArchTargetELFStreamer::LoongArchTargetELFStreamer(
26 MCStreamer &S, const MCSubtargetInfo &STI)
27 : LoongArchTargetStreamer(S) {
28 auto &MAB = static_cast<LoongArchAsmBackend &>(
29 getStreamer().getAssembler().getBackend());
30 setTargetABI(LoongArchABI::computeTargetABI(
31 TT: STI.getTargetTriple(), FeatureBits: STI.getFeatureBits(),
32 ABIName: MAB.getTargetOptions().getABIName()));
33}
34
35MCELFStreamer &LoongArchTargetELFStreamer::getStreamer() {
36 return static_cast<MCELFStreamer &>(Streamer);
37}
38
39void LoongArchTargetELFStreamer::emitDirectiveOptionPush() {}
40void LoongArchTargetELFStreamer::emitDirectiveOptionPop() {}
41void LoongArchTargetELFStreamer::emitDirectiveOptionRelax() {}
42void LoongArchTargetELFStreamer::emitDirectiveOptionNoRelax() {}
43
44void LoongArchTargetELFStreamer::emitDTPRel32Value(const MCExpr *Value) {
45 auto &S = getStreamer();
46 S.ensureHeadroom(Headroom: 4);
47 S.addFixup(Value, Kind: LoongArch::fixup_loongarch_dtprel32);
48 S.appendContents(Num: 4, Elt: 0);
49}
50
51void LoongArchTargetELFStreamer::emitDTPRel64Value(const MCExpr *Value) {
52 auto &S = getStreamer();
53 S.ensureHeadroom(Headroom: 8);
54 S.addFixup(Value, Kind: LoongArch::fixup_loongarch_dtprel64);
55 S.appendContents(Num: 8, Elt: 0);
56}
57
58void LoongArchTargetELFStreamer::finish() {
59 LoongArchTargetStreamer::finish();
60 ELFObjectWriter &W = getStreamer().getWriter();
61 LoongArchABI::ABI ABI = getTargetABI();
62
63 // Figure out the e_flags.
64 //
65 // Bitness is already represented with the EI_CLASS byte in the current spec,
66 // so here we only record the base ABI modifier. Also set the object file ABI
67 // version to v1, as upstream LLVM cannot handle the previous stack-machine-
68 // based relocs from day one.
69 //
70 // Refer to LoongArch ELF psABI v2.01 for details.
71 unsigned EFlags = W.getELFHeaderEFlags();
72 EFlags |= ELF::EF_LOONGARCH_OBJABI_V1;
73 switch (ABI) {
74 case LoongArchABI::ABI_ILP32S:
75 case LoongArchABI::ABI_LP64S:
76 EFlags |= ELF::EF_LOONGARCH_ABI_SOFT_FLOAT;
77 break;
78 case LoongArchABI::ABI_ILP32F:
79 case LoongArchABI::ABI_LP64F:
80 EFlags |= ELF::EF_LOONGARCH_ABI_SINGLE_FLOAT;
81 break;
82 case LoongArchABI::ABI_ILP32D:
83 case LoongArchABI::ABI_LP64D:
84 EFlags |= ELF::EF_LOONGARCH_ABI_DOUBLE_FLOAT;
85 break;
86 case LoongArchABI::ABI_Unknown:
87 llvm_unreachable("Improperly initialized target ABI");
88 }
89 W.setELFHeaderEFlags(EFlags);
90}
91
92void LoongArchELFStreamer::emitCodeAlignment(Align Alignment,
93 const MCSubtargetInfo &STI,
94 unsigned MaxBytesToEmit) {
95 // Save the Align fragment.
96 auto *AlignFrag = getCurrentFragment();
97 MCELFStreamer::emitCodeAlignment(ByteAlignment: Alignment, STI, MaxBytesToEmit);
98
99 // Pre-mark the Align fragment as linker-relaxable.
100 if (LoongArchAsmBackend::shouldRelaxAlign(F: *AlignFrag))
101 AlignFrag->setLinkerRelaxable();
102}
103
104namespace llvm {
105MCELFStreamer *createLoongArchELFStreamer(MCContext &C,
106 std::unique_ptr<MCAsmBackend> MAB,
107 std::unique_ptr<MCObjectWriter> MOW,
108 std::unique_ptr<MCCodeEmitter> MCE) {
109 LoongArchELFStreamer *S = new LoongArchELFStreamer(
110 C, std::move(MAB), std::move(MOW), std::move(MCE));
111 return S;
112}
113} // end namespace llvm
114