1//===-- RISCVELFStreamer.h - RISC-V ELF Target Streamer ---------*- C++ -*-===//
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#ifndef LLVM_LIB_TARGET_RISCV_MCTARGETDESC_RISCVELFSTREAMER_H
10#define LLVM_LIB_TARGET_RISCV_MCTARGETDESC_RISCVELFSTREAMER_H
11
12#include "RISCVTargetStreamer.h"
13#include "llvm/ADT/SmallVector.h"
14#include "llvm/MC/MCELFStreamer.h"
15
16namespace llvm {
17
18class RISCVELFStreamer : public MCELFStreamer {
19 void reset() override;
20 void emitDataMappingSymbol();
21 void emitInstructionsMappingSymbol();
22 void emitMappingSymbol(StringRef Name);
23
24 enum ElfMappingSymbol { EMS_None, EMS_Instructions, EMS_Data };
25
26 DenseMap<const MCSection *, ElfMappingSymbol> LastMappingSymbols;
27 ElfMappingSymbol LastEMS = EMS_None;
28
29 // Active ISA string propagated from RISCVTargetELFStreamer. When non-empty,
30 // it is used as the suffix for "$x<ISA>" mapping symbols.
31 std::string MappingSymbolArch;
32
33 // ISA suffix last emitted via "$x<ISA>" in the current section, and the
34 // per-section history preserved across changeSection. A new mapping symbol
35 // is emitted whenever LastEMS != EMS_Instructions or
36 // LastEmittedArch != MappingSymbolArch, so the ISA in effect at each
37 // instruction run is always recorded.
38 std::string LastEmittedArch;
39 DenseMap<const MCSection *, std::string> LastEmittedArchInSection;
40
41public:
42 RISCVELFStreamer(MCContext &C, std::unique_ptr<MCAsmBackend> MAB,
43 std::unique_ptr<MCObjectWriter> MOW,
44 std::unique_ptr<MCCodeEmitter> MCE);
45
46 void changeSection(MCSection *Section, uint32_t Subsection) override;
47 void emitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) override;
48 void emitBytes(StringRef Data) override;
49 void emitFill(const MCExpr &NumBytes, uint64_t FillValue, SMLoc Loc) override;
50 void emitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc) override;
51
52 void setMappingSymbolArch(StringRef Arch);
53};
54
55class RISCVTargetELFStreamer : public RISCVTargetStreamer {
56private:
57 StringRef CurrentVendor;
58
59 // Initial ISA string derived from the subtarget features in the constructor.
60 // Used to re-establish state on reset().
61 std::string InitialArchString;
62
63 // Current ISA string, kept in sync with each .option arch/rvc/norvc/pop
64 // and .attribute arch directive. Used to avoid propagating redundant ISA
65 // updates to the streamer when the ISA does not actually change (e.g.,
66 // .option rvc when C is already enabled).
67 std::string ArchString;
68 SmallVector<std::string, 4> ArchStringStack;
69
70 MCSection *AttributeSection = nullptr;
71
72 void emitAttribute(unsigned Attribute, unsigned Value) override;
73 void emitTextAttribute(unsigned Attribute, StringRef String) override;
74 void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
75 StringRef StringValue) override;
76 void finishAttributeSection() override;
77
78 void reset() override;
79
80public:
81 RISCVELFStreamer &getStreamer();
82 RISCVTargetELFStreamer(MCStreamer &S, const MCSubtargetInfo &STI);
83
84 // Update ArchString and propagate the change to the streamer so the next
85 // instruction-run emits an ISA-specific mapping symbol. A no-op when
86 // Arch == ArchString (deduplication).
87 void setArchString(StringRef Arch) override;
88 void emitDirectiveOptionExact() override;
89 void emitDirectiveOptionNoExact() override;
90 void emitDirectiveOptionPIC() override;
91 void emitDirectiveOptionNoPIC() override;
92 void emitDirectiveOptionPop() override;
93 void emitDirectiveOptionPush() override;
94 void emitDirectiveOptionRelax() override;
95 void emitDirectiveOptionNoRelax() override;
96 void emitDirectiveOptionRVC() override;
97 void emitDirectiveOptionNoRVC() override;
98 void emitDirectiveVariantCC(MCSymbol &Symbol) override;
99
100 void emitNoteGnuPropertySection(const uint32_t Feature1And);
101 void finish() override;
102};
103
104MCStreamer *createRISCVELFStreamer(const Triple &, MCContext &C,
105 std::unique_ptr<MCAsmBackend> &&MAB,
106 std::unique_ptr<MCObjectWriter> &&MOW,
107 std::unique_ptr<MCCodeEmitter> &&MCE);
108} // namespace llvm
109
110#endif // LLVM_LIB_TARGET_RISCV_MCTARGETDESC_RISCVELFSTREAMER_H
111