1 //===-- AArch64WinCOFFStreamer.cpp - ARM Target WinCOFF 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 #include "AArch64WinCOFFStreamer.h"
10 #include "llvm/MC/MCAsmBackend.h"
11 #include "llvm/MC/MCCodeEmitter.h"
12 #include "llvm/MC/MCObjectWriter.h"
13 #include "llvm/MC/MCWin64EH.h"
14 #include "llvm/MC/MCWinCOFFStreamer.h"
15
16 using namespace llvm;
17
18 namespace {
19
20 class AArch64WinCOFFStreamer : public MCWinCOFFStreamer {
21 Win64EH::ARM64UnwindEmitter EHStreamer;
22
23 public:
AArch64WinCOFFStreamer(MCContext & C,std::unique_ptr<MCAsmBackend> AB,std::unique_ptr<MCCodeEmitter> CE,std::unique_ptr<MCObjectWriter> OW)24 AArch64WinCOFFStreamer(MCContext &C, std::unique_ptr<MCAsmBackend> AB,
25 std::unique_ptr<MCCodeEmitter> CE,
26 std::unique_ptr<MCObjectWriter> OW)
27 : MCWinCOFFStreamer(C, std::move(AB), std::move(CE), std::move(OW)) {}
28
29 void EmitWinEHHandlerData(SMLoc Loc) override;
30 void EmitWindowsUnwindTables() override;
31 void EmitWindowsUnwindTables(WinEH::FrameInfo *Frame) override;
32 void finishImpl() override;
33 };
34
EmitWinEHHandlerData(SMLoc Loc)35 void AArch64WinCOFFStreamer::EmitWinEHHandlerData(SMLoc Loc) {
36 MCStreamer::EmitWinEHHandlerData(Loc);
37
38 // We have to emit the unwind info now, because this directive
39 // actually switches to the .xdata section!
40 EHStreamer.EmitUnwindInfo(*this, getCurrentWinFrameInfo(),
41 /* HandlerData = */ true);
42 }
43
EmitWindowsUnwindTables(WinEH::FrameInfo * Frame)44 void AArch64WinCOFFStreamer::EmitWindowsUnwindTables(WinEH::FrameInfo *Frame) {
45 EHStreamer.EmitUnwindInfo(*this, Frame, /* HandlerData = */ false);
46 }
47
EmitWindowsUnwindTables()48 void AArch64WinCOFFStreamer::EmitWindowsUnwindTables() {
49 if (!getNumWinFrameInfos())
50 return;
51 EHStreamer.Emit(*this);
52 }
53
finishImpl()54 void AArch64WinCOFFStreamer::finishImpl() {
55 emitFrames(nullptr);
56 EmitWindowsUnwindTables();
57
58 MCWinCOFFStreamer::finishImpl();
59 }
60 } // end anonymous namespace
61
62 // Helper function to common out unwind code setup for those codes that can
63 // belong to both prolog and epilog.
64 // There are three types of Windows ARM64 SEH codes. They can
65 // 1) take no operands: SEH_Nop, SEH_PrologEnd, SEH_EpilogStart, SEH_EpilogEnd
66 // 2) take an offset: SEH_StackAlloc, SEH_SaveFPLR, SEH_SaveFPLR_X
67 // 3) take a register and an offset/size: all others
EmitARM64WinUnwindCode(unsigned UnwindCode,int Reg,int Offset)68 void AArch64TargetWinCOFFStreamer::EmitARM64WinUnwindCode(unsigned UnwindCode,
69 int Reg,
70 int Offset) {
71 auto &S = getStreamer();
72 WinEH::FrameInfo *CurFrame = S.EnsureValidWinFrameInfo(SMLoc());
73 if (!CurFrame)
74 return;
75 MCSymbol *Label = S.emitCFILabel();
76 auto Inst = WinEH::Instruction(UnwindCode, Label, Reg, Offset);
77 if (InEpilogCFI)
78 CurFrame->EpilogMap[CurrentEpilog].push_back(Inst);
79 else
80 CurFrame->Instructions.push_back(Inst);
81 }
82
EmitARM64WinCFIAllocStack(unsigned Size)83 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFIAllocStack(unsigned Size) {
84 unsigned Op = Win64EH::UOP_AllocSmall;
85 if (Size >= 16384)
86 Op = Win64EH::UOP_AllocLarge;
87 else if (Size >= 512)
88 Op = Win64EH::UOP_AllocMedium;
89 EmitARM64WinUnwindCode(Op, -1, Size);
90 }
91
EmitARM64WinCFISaveR19R20X(int Offset)92 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveR19R20X(int Offset) {
93 EmitARM64WinUnwindCode(Win64EH::UOP_SaveR19R20X, -1, Offset);
94 }
95
EmitARM64WinCFISaveFPLR(int Offset)96 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveFPLR(int Offset) {
97 EmitARM64WinUnwindCode(Win64EH::UOP_SaveFPLR, -1, Offset);
98 }
99
EmitARM64WinCFISaveFPLRX(int Offset)100 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveFPLRX(int Offset) {
101 EmitARM64WinUnwindCode(Win64EH::UOP_SaveFPLRX, -1, Offset);
102 }
103
EmitARM64WinCFISaveReg(unsigned Reg,int Offset)104 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveReg(unsigned Reg,
105 int Offset) {
106 assert(Offset >= 0 && Offset <= 504 &&
107 "Offset for save reg should be >= 0 && <= 504");
108 EmitARM64WinUnwindCode(Win64EH::UOP_SaveReg, Reg, Offset);
109 }
110
EmitARM64WinCFISaveRegX(unsigned Reg,int Offset)111 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveRegX(unsigned Reg,
112 int Offset) {
113 EmitARM64WinUnwindCode(Win64EH::UOP_SaveRegX, Reg, Offset);
114 }
115
EmitARM64WinCFISaveRegP(unsigned Reg,int Offset)116 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveRegP(unsigned Reg,
117 int Offset) {
118 EmitARM64WinUnwindCode(Win64EH::UOP_SaveRegP, Reg, Offset);
119 }
120
EmitARM64WinCFISaveRegPX(unsigned Reg,int Offset)121 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveRegPX(unsigned Reg,
122 int Offset) {
123 EmitARM64WinUnwindCode(Win64EH::UOP_SaveRegPX, Reg, Offset);
124 }
125
EmitARM64WinCFISaveLRPair(unsigned Reg,int Offset)126 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveLRPair(unsigned Reg,
127 int Offset) {
128 EmitARM64WinUnwindCode(Win64EH::UOP_SaveLRPair, Reg, Offset);
129 }
130
EmitARM64WinCFISaveFReg(unsigned Reg,int Offset)131 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveFReg(unsigned Reg,
132 int Offset) {
133 assert(Offset >= 0 && Offset <= 504 &&
134 "Offset for save reg should be >= 0 && <= 504");
135 EmitARM64WinUnwindCode(Win64EH::UOP_SaveFReg, Reg, Offset);
136 }
137
EmitARM64WinCFISaveFRegX(unsigned Reg,int Offset)138 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveFRegX(unsigned Reg,
139 int Offset) {
140 EmitARM64WinUnwindCode(Win64EH::UOP_SaveFRegX, Reg, Offset);
141 }
142
EmitARM64WinCFISaveFRegP(unsigned Reg,int Offset)143 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveFRegP(unsigned Reg,
144 int Offset) {
145 EmitARM64WinUnwindCode(Win64EH::UOP_SaveFRegP, Reg, Offset);
146 }
147
EmitARM64WinCFISaveFRegPX(unsigned Reg,int Offset)148 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveFRegPX(unsigned Reg,
149 int Offset) {
150 EmitARM64WinUnwindCode(Win64EH::UOP_SaveFRegPX, Reg, Offset);
151 }
152
EmitARM64WinCFISetFP()153 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISetFP() {
154 EmitARM64WinUnwindCode(Win64EH::UOP_SetFP, -1, 0);
155 }
156
EmitARM64WinCFIAddFP(unsigned Offset)157 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFIAddFP(unsigned Offset) {
158 assert(Offset <= 2040 && "UOP_AddFP must have offset <= 2040");
159 EmitARM64WinUnwindCode(Win64EH::UOP_AddFP, -1, Offset);
160 }
161
EmitARM64WinCFINop()162 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFINop() {
163 EmitARM64WinUnwindCode(Win64EH::UOP_Nop, -1, 0);
164 }
165
EmitARM64WinCFISaveNext()166 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFISaveNext() {
167 EmitARM64WinUnwindCode(Win64EH::UOP_SaveNext, -1, 0);
168 }
169
170 // The functions below handle opcodes that can end up in either a prolog or
171 // an epilog, but not both.
EmitARM64WinCFIPrologEnd()172 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFIPrologEnd() {
173 auto &S = getStreamer();
174 WinEH::FrameInfo *CurFrame = S.EnsureValidWinFrameInfo(SMLoc());
175 if (!CurFrame)
176 return;
177
178 MCSymbol *Label = S.emitCFILabel();
179 CurFrame->PrologEnd = Label;
180 WinEH::Instruction Inst = WinEH::Instruction(Win64EH::UOP_End, Label, -1, 0);
181 auto it = CurFrame->Instructions.begin();
182 CurFrame->Instructions.insert(it, Inst);
183 }
184
EmitARM64WinCFIEpilogStart()185 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFIEpilogStart() {
186 auto &S = getStreamer();
187 WinEH::FrameInfo *CurFrame = S.EnsureValidWinFrameInfo(SMLoc());
188 if (!CurFrame)
189 return;
190
191 InEpilogCFI = true;
192 CurrentEpilog = S.emitCFILabel();
193 }
194
EmitARM64WinCFIEpilogEnd()195 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFIEpilogEnd() {
196 auto &S = getStreamer();
197 WinEH::FrameInfo *CurFrame = S.EnsureValidWinFrameInfo(SMLoc());
198 if (!CurFrame)
199 return;
200
201 InEpilogCFI = false;
202 MCSymbol *Label = S.emitCFILabel();
203 WinEH::Instruction Inst = WinEH::Instruction(Win64EH::UOP_End, Label, -1, 0);
204 CurFrame->EpilogMap[CurrentEpilog].push_back(Inst);
205 CurrentEpilog = nullptr;
206 }
207
EmitARM64WinCFITrapFrame()208 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFITrapFrame() {
209 EmitARM64WinUnwindCode(Win64EH::UOP_TrapFrame, -1, 0);
210 }
211
EmitARM64WinCFIMachineFrame()212 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFIMachineFrame() {
213 EmitARM64WinUnwindCode(Win64EH::UOP_PushMachFrame, -1, 0);
214 }
215
EmitARM64WinCFIContext()216 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFIContext() {
217 EmitARM64WinUnwindCode(Win64EH::UOP_Context, -1, 0);
218 }
219
EmitARM64WinCFIClearUnwoundToCall()220 void AArch64TargetWinCOFFStreamer::EmitARM64WinCFIClearUnwoundToCall() {
221 EmitARM64WinUnwindCode(Win64EH::UOP_ClearUnwoundToCall, -1, 0);
222 }
223
createAArch64WinCOFFStreamer(MCContext & Context,std::unique_ptr<MCAsmBackend> MAB,std::unique_ptr<MCObjectWriter> OW,std::unique_ptr<MCCodeEmitter> Emitter,bool RelaxAll,bool IncrementalLinkerCompatible)224 MCWinCOFFStreamer *llvm::createAArch64WinCOFFStreamer(
225 MCContext &Context, std::unique_ptr<MCAsmBackend> MAB,
226 std::unique_ptr<MCObjectWriter> OW, std::unique_ptr<MCCodeEmitter> Emitter,
227 bool RelaxAll, bool IncrementalLinkerCompatible) {
228 auto *S = new AArch64WinCOFFStreamer(Context, std::move(MAB),
229 std::move(Emitter), std::move(OW));
230 S->getAssembler().setIncrementalLinkerCompatible(IncrementalLinkerCompatible);
231 return S;
232 }
233