1//===- SjLjEHPrepare.cpp - Eliminate Invoke & Unwind instructions ---------===//
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 transformation is designed for use by code generators which use SjLj
10// based exception handling.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/CodeGen/SjLjEHPrepare.h"
15#include "llvm/ADT/SetVector.h"
16#include "llvm/ADT/SmallPtrSet.h"
17#include "llvm/ADT/SmallVector.h"
18#include "llvm/ADT/Statistic.h"
19#include "llvm/CodeGen/Passes.h"
20#include "llvm/IR/Constants.h"
21#include "llvm/IR/DataLayout.h"
22#include "llvm/IR/DerivedTypes.h"
23#include "llvm/IR/IRBuilder.h"
24#include "llvm/IR/Instructions.h"
25#include "llvm/IR/Intrinsics.h"
26#include "llvm/IR/Module.h"
27#include "llvm/InitializePasses.h"
28#include "llvm/Pass.h"
29#include "llvm/Support/Debug.h"
30#include "llvm/Support/raw_ostream.h"
31#include "llvm/Target/TargetMachine.h"
32#include "llvm/Transforms/Utils/Local.h"
33using namespace llvm;
34
35#define DEBUG_TYPE "sjlj-eh-prepare"
36
37STATISTIC(NumInvokes, "Number of invokes replaced");
38STATISTIC(NumSpilled, "Number of registers live across unwind edges");
39
40namespace {
41class SjLjEHPrepareImpl {
42 IntegerType *DataTy = nullptr;
43 Type *doubleUnderDataTy = nullptr;
44 Type *doubleUnderJBufTy = nullptr;
45 Type *FunctionContextTy = nullptr;
46 FunctionCallee RegisterFn;
47 FunctionCallee UnregisterFn;
48 Function *BuiltinSetupDispatchFn = nullptr;
49 Function *FrameAddrFn = nullptr;
50 Function *StackAddrFn = nullptr;
51 Function *StackRestoreFn = nullptr;
52 Function *LSDAAddrFn = nullptr;
53 Function *CallSiteFn = nullptr;
54 Function *FuncCtxFn = nullptr;
55 AllocaInst *FuncCtx = nullptr;
56 const TargetMachine *TM = nullptr;
57
58 // The module's "exception-model" flag.
59 ExceptionHandling ExceptionModel = ExceptionHandling::Default;
60
61public:
62 explicit SjLjEHPrepareImpl(const TargetMachine *TM = nullptr) : TM(TM) {}
63 bool doInitialization(Module &M);
64 bool runOnFunction(Function &F);
65
66private:
67 bool setupEntryBlockAndCallSites(Function &F);
68 void substituteLPadValues(LandingPadInst *LPI, Value *ExnVal, Value *SelVal);
69 Value *setupFunctionContext(Function &F, ArrayRef<LandingPadInst *> LPads);
70 void lowerIncomingArguments(Function &F);
71 void lowerAcrossUnwindEdges(Function &F, ArrayRef<InvokeInst *> Invokes);
72 void insertCallSiteStore(Instruction *I, int Number);
73};
74
75class SjLjEHPrepare : public FunctionPass {
76 SjLjEHPrepareImpl Impl;
77
78public:
79 static char ID; // Pass identification, replacement for typeid
80 explicit SjLjEHPrepare(const TargetMachine *TM = nullptr)
81 : FunctionPass(ID), Impl(TM) {}
82 bool doInitialization(Module &M) override { return Impl.doInitialization(M); }
83 bool runOnFunction(Function &F) override { return Impl.runOnFunction(F); };
84
85 StringRef getPassName() const override {
86 return "SJLJ Exception Handling preparation";
87 }
88};
89
90} // end anonymous namespace
91
92PreservedAnalyses SjLjEHPreparePass::run(Function &F,
93 FunctionAnalysisManager &FAM) {
94 SjLjEHPrepareImpl Impl(TM);
95 Impl.doInitialization(M&: *F.getParent());
96 bool Changed = Impl.runOnFunction(F);
97 return Changed ? PreservedAnalyses::none() : PreservedAnalyses::all();
98}
99
100char SjLjEHPrepare::ID = 0;
101INITIALIZE_PASS(SjLjEHPrepare, DEBUG_TYPE, "Prepare SjLj exceptions",
102 false, false)
103
104// Public Interface To the SjLjEHPrepare pass.
105FunctionPass *llvm::createSjLjEHPreparePass(const TargetMachine *TM) {
106 return new SjLjEHPrepare(TM);
107}
108
109// doInitialization - Set up decalarations and types needed to process
110// exceptions.
111bool SjLjEHPrepareImpl::doInitialization(Module &M) {
112 ExceptionModel = M.getExceptionModel();
113
114 // Build the function context structure.
115 // builtin_setjmp uses a five word jbuf
116 Type *VoidPtrTy = PointerType::getUnqual(C&: M.getContext());
117 unsigned DataBits =
118 TM ? TM->getSjLjDataSize() : TargetMachine::DefaultSjLjDataSize;
119 DataTy = Type::getIntNTy(C&: M.getContext(), N: DataBits);
120 doubleUnderDataTy = ArrayType::get(ElementType: DataTy, NumElements: 4);
121 doubleUnderJBufTy = ArrayType::get(ElementType: VoidPtrTy, NumElements: 5);
122 FunctionContextTy = StructType::get(elt1: VoidPtrTy, // __prev
123 elts: DataTy, // call_site
124 elts: doubleUnderDataTy, // __data
125 elts: VoidPtrTy, // __personality
126 elts: VoidPtrTy, // __lsda
127 elts: doubleUnderJBufTy // __jbuf
128 );
129
130 return false;
131}
132
133/// insertCallSiteStore - Insert a store of the call-site value to the
134/// function context
135void SjLjEHPrepareImpl::insertCallSiteStore(Instruction *I, int Number) {
136 IRBuilder<> Builder(I);
137
138 // Get a reference to the call_site field.
139 Type *Int32Ty = Type::getInt32Ty(C&: I->getContext());
140 Value *Zero = ConstantInt::get(Ty: Int32Ty, V: 0);
141 Value *One = ConstantInt::get(Ty: Int32Ty, V: 1);
142 Value *Idxs[2] = { Zero, One };
143 Value *CallSite =
144 Builder.CreateGEP(Ty: FunctionContextTy, Ptr: FuncCtx, IdxList: Idxs, Name: "call_site");
145
146 // Insert a store of the call-site number
147 ConstantInt *CallSiteNoC = ConstantInt::getSigned(Ty: DataTy, V: Number);
148 Builder.CreateStore(Val: CallSiteNoC, Ptr: CallSite, isVolatile: true /*volatile*/);
149}
150
151/// MarkBlocksLiveIn - Insert BB and all of its predecessors into LiveBBs until
152/// we reach blocks we've already seen.
153static void MarkBlocksLiveIn(BasicBlock *BB,
154 SmallPtrSetImpl<BasicBlock *> &LiveBBs) {
155 if (!LiveBBs.insert(Ptr: BB).second)
156 return; // already been here.
157
158 LiveBBs.insert_range(R: inverse_depth_first(G: BB));
159}
160
161/// substituteLPadValues - Substitute the values returned by the landingpad
162/// instruction with those returned by the personality function.
163void SjLjEHPrepareImpl::substituteLPadValues(LandingPadInst *LPI, Value *ExnVal,
164 Value *SelVal) {
165 SmallVector<Value *, 8> UseWorkList(LPI->users());
166 while (!UseWorkList.empty()) {
167 Value *Val = UseWorkList.pop_back_val();
168 auto *EVI = dyn_cast<ExtractValueInst>(Val);
169 if (!EVI)
170 continue;
171 if (EVI->getNumIndices() != 1)
172 continue;
173 if (*EVI->idx_begin() == 0)
174 EVI->replaceAllUsesWith(V: ExnVal);
175 else if (*EVI->idx_begin() == 1)
176 EVI->replaceAllUsesWith(V: SelVal);
177 if (EVI->use_empty())
178 EVI->eraseFromParent();
179 }
180
181 if (LPI->use_empty())
182 return;
183
184 // There are still some uses of LPI. Construct an aggregate with the exception
185 // values and replace the LPI with that aggregate.
186 Type *LPadType = LPI->getType();
187 Value *LPadVal = PoisonValue::get(T: LPadType);
188 auto *SelI = cast<Instruction>(Val: SelVal);
189 IRBuilder<> Builder(std::next(x: SelI->getIterator()));
190 LPadVal = Builder.CreateInsertValue(Agg: LPadVal, Val: ExnVal, Idxs: 0, Name: "lpad.val");
191 LPadVal = Builder.CreateInsertValue(Agg: LPadVal, Val: SelVal, Idxs: 1, Name: "lpad.val");
192
193 LPI->replaceAllUsesWith(V: LPadVal);
194}
195
196/// setupFunctionContext - Allocate the function context on the stack and fill
197/// it with all of the data that we know at this point.
198Value *
199SjLjEHPrepareImpl::setupFunctionContext(Function &F,
200 ArrayRef<LandingPadInst *> LPads) {
201 BasicBlock *EntryBB = &F.front();
202
203 // Create an alloca for the incoming jump buffer ptr and the new jump buffer
204 // that needs to be restored on all exits from the function. This is an alloca
205 // because the value needs to be added to the global context list.
206 auto &DL = F.getDataLayout();
207 const Align Alignment = DL.getPrefTypeAlign(Ty: FunctionContextTy);
208 FuncCtx = new AllocaInst(FunctionContextTy, DL.getAllocaAddrSpace(), nullptr,
209 Alignment, "fn_context", EntryBB->begin());
210
211 // Fill in the function context structure.
212 for (LandingPadInst *LPI : LPads) {
213 IRBuilder<> Builder(LPI->getParent()->getFirstInsertionPt());
214
215 // Reference the __data field.
216 Value *FCData =
217 Builder.CreateConstGEP2_32(Ty: FunctionContextTy, Ptr: FuncCtx, Idx0: 0, Idx1: 2, Name: "__data");
218
219 // The exception values come back in context->__data[0].
220 Value *ExceptionAddr = Builder.CreateConstGEP2_32(Ty: doubleUnderDataTy, Ptr: FCData,
221 Idx0: 0, Idx1: 0, Name: "exception_gep");
222 Value *ExnVal = Builder.CreateLoad(Ty: DataTy, Ptr: ExceptionAddr, isVolatile: true, Name: "exn_val");
223 ExnVal = Builder.CreateIntToPtr(V: ExnVal, DestTy: Builder.getPtrTy());
224
225 Value *SelectorAddr = Builder.CreateConstGEP2_32(Ty: doubleUnderDataTy, Ptr: FCData,
226 Idx0: 0, Idx1: 1, Name: "exn_selector_gep");
227 Value *SelVal =
228 Builder.CreateLoad(Ty: DataTy, Ptr: SelectorAddr, isVolatile: true, Name: "exn_selector_val");
229
230 // SelVal must be Int32Ty, so trunc it
231 SelVal = Builder.CreateTrunc(V: SelVal, DestTy: Type::getInt32Ty(C&: F.getContext()));
232
233 substituteLPadValues(LPI, ExnVal, SelVal);
234 }
235
236 // Personality function
237 IRBuilder<> Builder(EntryBB->getTerminator());
238 Value *PersonalityFn = F.getPersonalityFn();
239 Value *PersonalityFieldPtr = Builder.CreateConstGEP2_32(
240 Ty: FunctionContextTy, Ptr: FuncCtx, Idx0: 0, Idx1: 3, Name: "pers_fn_gep");
241 Builder.CreateStore(Val: PersonalityFn, Ptr: PersonalityFieldPtr, /*isVolatile=*/true);
242
243 // LSDA address
244 Value *LSDA = Builder.CreateCall(Callee: LSDAAddrFn, Args: {}, Name: "lsda_addr");
245 Value *LSDAFieldPtr =
246 Builder.CreateConstGEP2_32(Ty: FunctionContextTy, Ptr: FuncCtx, Idx0: 0, Idx1: 4, Name: "lsda_gep");
247 Builder.CreateStore(Val: LSDA, Ptr: LSDAFieldPtr, /*isVolatile=*/true);
248
249 return FuncCtx;
250}
251
252/// lowerIncomingArguments - To avoid having to handle incoming arguments
253/// specially, we lower each arg to a copy instruction in the entry block. This
254/// ensures that the argument value itself cannot be live out of the entry
255/// block.
256void SjLjEHPrepareImpl::lowerIncomingArguments(Function &F) {
257 BasicBlock::iterator AfterAllocaInsPt = F.begin()->begin();
258 while (isa<AllocaInst>(Val: AfterAllocaInsPt) &&
259 cast<AllocaInst>(Val&: AfterAllocaInsPt)->isStaticAlloca())
260 ++AfterAllocaInsPt;
261 assert(AfterAllocaInsPt != F.front().end());
262
263 for (auto &AI : F.args()) {
264 // Swift error really is a register that we model as memory -- instruction
265 // selection will perform mem-to-reg for us and spill/reload appropriately
266 // around calls that clobber it. There is no need to spill this
267 // value to the stack and doing so would not be allowed.
268 if (AI.isSwiftError())
269 continue;
270
271 Type *Ty = AI.getType();
272
273 // Use 'select i8 true, %arg, poison' to simulate a 'no-op' instruction.
274 Value *TrueValue = ConstantInt::getTrue(Context&: F.getContext());
275 Value *PoisonValue = PoisonValue::get(T: Ty);
276 Instruction *SI = SelectInst::Create(
277 C: TrueValue, S1: &AI, S2: PoisonValue, NameStr: AI.getName() + ".tmp", InsertBefore: AfterAllocaInsPt);
278 AI.replaceAllUsesWith(V: SI);
279
280 // Reset the operand, because it was clobbered by the RAUW above.
281 SI->setOperand(i: 1, Val: &AI);
282 }
283}
284
285/// lowerAcrossUnwindEdges - Find all variables which are alive across an unwind
286/// edge and spill them.
287void SjLjEHPrepareImpl::lowerAcrossUnwindEdges(Function &F,
288 ArrayRef<InvokeInst *> Invokes) {
289 // Finally, scan the code looking for instructions with bad live ranges.
290 for (BasicBlock &BB : F) {
291 for (Instruction &Inst : BB) {
292 // Ignore obvious cases we don't have to handle. In particular, most
293 // instructions either have no uses or only have a single use inside the
294 // current block. Ignore them quickly.
295 if (Inst.use_empty())
296 continue;
297 if (Inst.hasOneUse() &&
298 cast<Instruction>(Val: Inst.user_back())->getParent() == &BB &&
299 !isa<PHINode>(Val: Inst.user_back()))
300 continue;
301
302 // If this is an alloca in the entry block, it's not a real register
303 // value.
304 if (auto *AI = dyn_cast<AllocaInst>(Val: &Inst))
305 if (AI->isStaticAlloca())
306 continue;
307
308 // Avoid iterator invalidation by copying users to a temporary vector.
309 SmallVector<Instruction *, 16> Users;
310 for (User *U : Inst.users()) {
311 Instruction *UI = cast<Instruction>(Val: U);
312 if (UI->getParent() != &BB || isa<PHINode>(Val: UI))
313 Users.push_back(Elt: UI);
314 }
315
316 // Find all of the blocks that this value is live in.
317 SmallPtrSet<BasicBlock *, 32> LiveBBs;
318 LiveBBs.insert(Ptr: &BB);
319 while (!Users.empty()) {
320 Instruction *U = Users.pop_back_val();
321
322 if (!isa<PHINode>(Val: U)) {
323 MarkBlocksLiveIn(BB: U->getParent(), LiveBBs);
324 } else {
325 // Uses for a PHI node occur in their predecessor block.
326 PHINode *PN = cast<PHINode>(Val: U);
327 for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
328 if (PN->getIncomingValue(i) == &Inst)
329 MarkBlocksLiveIn(BB: PN->getIncomingBlock(i), LiveBBs);
330 }
331 }
332
333 // Now that we know all of the blocks that this thing is live in, see if
334 // it includes any of the unwind locations.
335 bool NeedsSpill = false;
336 for (InvokeInst *Invoke : Invokes) {
337 BasicBlock *UnwindBlock = Invoke->getUnwindDest();
338 if (UnwindBlock != &BB && LiveBBs.count(Ptr: UnwindBlock)) {
339 LLVM_DEBUG(dbgs() << "SJLJ Spill: " << Inst << " around "
340 << UnwindBlock->getName() << "\n");
341 NeedsSpill = true;
342 break;
343 }
344 }
345
346 // If we decided we need a spill, do it.
347 // FIXME: Spilling this way is overkill, as it forces all uses of
348 // the value to be reloaded from the stack slot, even those that aren't
349 // in the unwind blocks. We should be more selective.
350 if (NeedsSpill) {
351 DemoteRegToStack(X&: Inst, VolatileLoads: true);
352 ++NumSpilled;
353 }
354 }
355 }
356
357 // Go through the landing pads and remove any PHIs there.
358 for (InvokeInst *Invoke : Invokes) {
359 BasicBlock *UnwindBlock = Invoke->getUnwindDest();
360 LandingPadInst *LPI = UnwindBlock->getLandingPadInst();
361
362 // Place PHIs into a set to avoid invalidating the iterator.
363 SmallPtrSet<PHINode *, 8> PHIsToDemote;
364 for (BasicBlock::iterator PN = UnwindBlock->begin(); isa<PHINode>(Val: PN); ++PN)
365 PHIsToDemote.insert(Ptr: cast<PHINode>(Val&: PN));
366 if (PHIsToDemote.empty())
367 continue;
368
369 // Demote the PHIs to the stack.
370 for (PHINode *PN : PHIsToDemote)
371 DemotePHIToStack(P: PN);
372
373 // Move the landingpad instruction back to the top of the landing pad block.
374 LPI->moveBefore(InsertPos: UnwindBlock->begin());
375 }
376}
377
378/// setupEntryBlockAndCallSites - Setup the entry block by creating and filling
379/// the function context and marking the call sites with the appropriate
380/// values. These values are used by the DWARF EH emitter.
381bool SjLjEHPrepareImpl::setupEntryBlockAndCallSites(Function &F) {
382 SmallVector<ReturnInst *, 16> Returns;
383 SmallVector<InvokeInst *, 16> Invokes;
384 SmallSetVector<LandingPadInst *, 16> LPads;
385
386 // Look through the terminators of the basic blocks to find invokes.
387 for (BasicBlock &BB : F)
388 if (auto *II = dyn_cast<InvokeInst>(Val: BB.getTerminator())) {
389 if (Function *Callee = II->getCalledFunction())
390 if (Callee->getIntrinsicID() == Intrinsic::donothing) {
391 // Remove the NOP invoke.
392 UncondBrInst::Create(Target: II->getNormalDest(), InsertBefore: II->getIterator());
393 II->eraseFromParent();
394 continue;
395 }
396
397 Invokes.push_back(Elt: II);
398 LPads.insert(X: II->getUnwindDest()->getLandingPadInst());
399 } else if (auto *RI = dyn_cast<ReturnInst>(Val: BB.getTerminator())) {
400 Returns.push_back(Elt: RI);
401 }
402
403 if (Invokes.empty())
404 return false;
405
406 NumInvokes += Invokes.size();
407
408 lowerIncomingArguments(F);
409 lowerAcrossUnwindEdges(F, Invokes);
410
411 Value *FuncCtx =
412 setupFunctionContext(F, LPads: ArrayRef(LPads.begin(), LPads.end()));
413 BasicBlock *EntryBB = &F.front();
414 IRBuilder<> Builder(EntryBB->getTerminator());
415
416 // Get a reference to the jump buffer.
417 Value *JBufPtr =
418 Builder.CreateConstGEP2_32(Ty: FunctionContextTy, Ptr: FuncCtx, Idx0: 0, Idx1: 5, Name: "jbuf_gep");
419
420 // Save the frame pointer.
421 Value *FramePtr = Builder.CreateConstGEP2_32(Ty: doubleUnderJBufTy, Ptr: JBufPtr, Idx0: 0, Idx1: 0,
422 Name: "jbuf_fp_gep");
423
424 Value *Val = Builder.CreateCall(Callee: FrameAddrFn, Args: Builder.getInt32(C: 0), Name: "fp");
425 Builder.CreateStore(Val, Ptr: FramePtr, /*isVolatile=*/true);
426
427 // Save the stack pointer.
428 Value *StackPtr = Builder.CreateConstGEP2_32(Ty: doubleUnderJBufTy, Ptr: JBufPtr, Idx0: 0, Idx1: 2,
429 Name: "jbuf_sp_gep");
430
431 Val = Builder.CreateCall(Callee: StackAddrFn, Args: {}, Name: "sp");
432 Builder.CreateStore(Val, Ptr: StackPtr, /*isVolatile=*/true);
433
434 // Call the setup_dispatch intrinsic. It fills in the rest of the jmpbuf.
435 Builder.CreateCall(Callee: BuiltinSetupDispatchFn, Args: {});
436
437 // Store a pointer to the function context so that the back-end will know
438 // where to look for it.
439 Builder.CreateCall(Callee: FuncCtxFn, Args: FuncCtx);
440
441 // Register the function context and make sure it's known to not throw.
442 CallInst *Register = Builder.CreateCall(Callee: RegisterFn, Args: FuncCtx, Name: "");
443 Register->setDoesNotThrow();
444
445 // At this point, we are all set up, update the invoke instructions to mark
446 // their call_site values.
447 for (unsigned I = 0, E = Invokes.size(); I != E; ++I) {
448 insertCallSiteStore(I: Invokes[I], Number: I + 1);
449
450 ConstantInt *CallSiteNum =
451 ConstantInt::get(Ty: Type::getInt32Ty(C&: F.getContext()), V: I + 1);
452
453 // Record the call site value for the back end so it stays associated with
454 // the invoke.
455 CallInst::Create(Func: CallSiteFn, Args: CallSiteNum, NameStr: "", InsertBefore: Invokes[I]->getIterator());
456 }
457
458 // Mark call instructions that aren't nounwind as no-action (call_site ==
459 // -1). Skip the entry block, as prior to then, no function context has been
460 // created for this function and any unexpected exceptions thrown will go
461 // directly to the caller's context, which is what we want anyway, so no need
462 // to do anything here.
463 for (BasicBlock &BB : F) {
464 if (&BB == &F.front())
465 continue;
466 for (Instruction &I : BB)
467 if (!isa<InvokeInst>(Val: I) && I.mayThrow())
468 insertCallSiteStore(I: &I, Number: -1);
469 }
470
471 // Following any allocas not in the entry block, update the saved SP in the
472 // jmpbuf to the new value.
473 for (BasicBlock &BB : F) {
474 if (&BB == &F.front())
475 continue;
476 for (Instruction &I : BB) {
477 if (auto *CI = dyn_cast<CallInst>(Val: &I)) {
478 if (CI->getCalledFunction() != StackRestoreFn)
479 continue;
480 } else if (!isa<AllocaInst>(Val: &I)) {
481 continue;
482 }
483 Instruction *StackAddr = CallInst::Create(Func: StackAddrFn, NameStr: "sp");
484 StackAddr->insertAfter(InsertPos: I.getIterator());
485 new StoreInst(StackAddr, StackPtr, true,
486 std::next(x: StackAddr->getIterator()));
487 }
488 }
489
490 // Finally, for any returns from this function, if this function contains an
491 // invoke, add a call to unregister the function context.
492 for (ReturnInst *Return : Returns) {
493 Instruction *InsertPoint = Return;
494 if (CallInst *CI = Return->getParent()->getTerminatingMustTailCall())
495 InsertPoint = CI;
496 CallInst::Create(Func: UnregisterFn, Args: FuncCtx, NameStr: "", InsertBefore: InsertPoint->getIterator());
497 }
498
499 return true;
500}
501
502bool SjLjEHPrepareImpl::runOnFunction(Function &F) {
503 if (ExceptionModel != ExceptionHandling::SjLj &&
504 ExceptionModel != ExceptionHandling::Default)
505 return false;
506
507 Module &M = *F.getParent();
508 RegisterFn = M.getOrInsertFunction(
509 Name: "_Unwind_SjLj_Register", RetTy: Type::getVoidTy(C&: M.getContext()),
510 Args: PointerType::getUnqual(C&: FunctionContextTy->getContext()));
511 UnregisterFn = M.getOrInsertFunction(
512 Name: "_Unwind_SjLj_Unregister", RetTy: Type::getVoidTy(C&: M.getContext()),
513 Args: PointerType::getUnqual(C&: FunctionContextTy->getContext()));
514
515 PointerType *AllocaPtrTy = M.getDataLayout().getAllocaPtrType(Ctx&: M.getContext());
516
517 FrameAddrFn = Intrinsic::getOrInsertDeclaration(M: &M, id: Intrinsic::frameaddress,
518 OverloadTys: {AllocaPtrTy});
519 StackAddrFn = Intrinsic::getOrInsertDeclaration(M: &M, id: Intrinsic::stacksave,
520 OverloadTys: {AllocaPtrTy});
521 StackRestoreFn = Intrinsic::getOrInsertDeclaration(
522 M: &M, id: Intrinsic::stackrestore, OverloadTys: {AllocaPtrTy});
523 BuiltinSetupDispatchFn =
524 Intrinsic::getOrInsertDeclaration(M: &M, id: Intrinsic::eh_sjlj_setup_dispatch);
525 LSDAAddrFn = Intrinsic::getOrInsertDeclaration(M: &M, id: Intrinsic::eh_sjlj_lsda);
526 CallSiteFn =
527 Intrinsic::getOrInsertDeclaration(M: &M, id: Intrinsic::eh_sjlj_callsite);
528 FuncCtxFn =
529 Intrinsic::getOrInsertDeclaration(M: &M, id: Intrinsic::eh_sjlj_functioncontext);
530
531 bool Res = setupEntryBlockAndCallSites(F);
532 return Res;
533}
534