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

source code of llvm/lib/CodeGen/SjLjEHPrepare.cpp