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/ADT/SmallVector.h"
17 #include "llvm/MC/MCELFStreamer.h"
18 #include <memory>
19 
20 namespace llvm {
21 
22 class MCAsmBackend;
23 class MCCodeEmitter;
24 class MCContext;
25 class MCSubtargetInfo;
26 
27 class PPCELFStreamer : public MCELFStreamer {
28   // We need to keep track of the last label we emitted (only one) because
29   // depending on whether the label is on the same line as an aligned
30   // instruction or not, the label may refer to the instruction or the nop.
31   MCSymbol *LastLabel;
32   SMLoc LastLabelLoc;
33 
34 public:
35   PPCELFStreamer(MCContext &Context, std::unique_ptr<MCAsmBackend> MAB,
36                  std::unique_ptr<MCObjectWriter> OW,
37                  std::unique_ptr<MCCodeEmitter> Emitter);
38 
39   void emitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) override;
40 
41   // EmitLabel updates LastLabel and LastLabelLoc when a new label is emitted.
42   void emitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc()) override;
43 private:
44   void emitPrefixedInstruction(const MCInst &Inst, const MCSubtargetInfo &STI);
45   void emitGOTToPCRelReloc(const MCInst &Inst);
46   void emitGOTToPCRelLabel(const MCInst &Inst);
47 };
48 
49 // Check if the instruction Inst is part of a pair of instructions that make up
50 // a link time GOT PC Rel optimization.
51 std::optional<bool> isPartOfGOTToPCRelPair(const MCInst &Inst,
52                                            const MCSubtargetInfo &STI);
53 
54 MCELFStreamer *createPPCELFStreamer(MCContext &Context,
55                                     std::unique_ptr<MCAsmBackend> MAB,
56                                     std::unique_ptr<MCObjectWriter> OW,
57                                     std::unique_ptr<MCCodeEmitter> Emitter);
58 } // end namespace llvm
59 
60 #endif // LLVM_LIB_TARGET_PPC_MCELFSTREAMER_PPCELFSTREAMER_H
61