1 //===- PPCELFStreamer.h - ELF Object Output --------------------*- 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 // This is a custom MCELFStreamer for PowerPC.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_LIB_TARGET_PPC_MCELFSTREAMER_PPCELFSTREAMER_H
14 #define LLVM_LIB_TARGET_PPC_MCELFSTREAMER_PPCELFSTREAMER_H
15 
16 #include "llvm/MC/MCELFStreamer.h"
17 #include <memory>
18 
19 namespace llvm {
20 
21 class MCAsmBackend;
22 class MCCodeEmitter;
23 class MCContext;
24 class MCSubtargetInfo;
25 
26 class PPCELFStreamer : public MCELFStreamer {
27   // We need to keep track of the last label we emitted (only one) because
28   // depending on whether the label is on the same line as an aligned
29   // instruction or not, the label may refer to the instruction or the nop.
30   MCSymbol *LastLabel;
31   SMLoc LastLabelLoc;
32 
33 public:
34   PPCELFStreamer(MCContext &Context, std::unique_ptr<MCAsmBackend> MAB,
35                  std::unique_ptr<MCObjectWriter> OW,
36                  std::unique_ptr<MCCodeEmitter> Emitter);
37 
38   void emitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) override;
39 
40   // EmitLabel updates LastLabel and LastLabelLoc when a new label is emitted.
41   void emitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc()) override;
42 private:
43   void emitPrefixedInstruction(const MCInst &Inst, const MCSubtargetInfo &STI);
44   void emitGOTToPCRelReloc(const MCInst &Inst);
45   void emitGOTToPCRelLabel(const MCInst &Inst);
46 };
47 
48 // Check if the instruction Inst is part of a pair of instructions that make up
49 // a link time GOT PC Rel optimization.
50 std::optional<bool> isPartOfGOTToPCRelPair(const MCInst &Inst,
51                                            const MCSubtargetInfo &STI);
52 
53 MCELFStreamer *createPPCELFStreamer(MCContext &Context,
54                                     std::unique_ptr<MCAsmBackend> MAB,
55                                     std::unique_ptr<MCObjectWriter> OW,
56                                     std::unique_ptr<MCCodeEmitter> Emitter);
57 } // end namespace llvm
58 
59 #endif // LLVM_LIB_TARGET_PPC_MCELFSTREAMER_PPCELFSTREAMER_H
60