Index: llvm/lib/CodeGen/StackProtector.cpp =================================================================== --- llvm/lib/CodeGen/StackProtector.cpp +++ llvm/lib/CodeGen/StackProtector.cpp @@ -414,11 +414,11 @@ /// /// Returns true if the platform/triple supports the stackprotectorcreate pseudo /// node. -static bool CreatePrologue(Function *F, Module *M, ReturnInst *RI, +static bool CreatePrologue(Function *F, Module *M, Instruction *CheckLoc, const TargetLoweringBase *TLI, AllocaInst *&AI) { bool SupportsSelectionDAGSP = false; IRBuilder<> B(&F->getEntryBlock().front()); - PointerType *PtrTy = Type::getInt8PtrTy(RI->getContext()); + PointerType *PtrTy = Type::getInt8PtrTy(CheckLoc->getContext()); AI = B.CreateAlloca(PtrTy, nullptr, "StackGuardSlot"); Value *GuardSlot = getStackGuard(TLI, M, B, &SupportsSelectionDAGSP); @@ -441,16 +441,31 @@ TLI->useStackGuardXorFP() || (EnableSelectionDAGSP && !TM->Options.EnableFastISel); AllocaInst *AI = nullptr; // Place on stack that stores the stack guard. + bool RecalculateDT = false; for (BasicBlock &BB : llvm::make_early_inc_range(*F)) { - ReturnInst *RI = dyn_cast(BB.getTerminator()); - if (!RI) + Instruction *CheckLoc = dyn_cast(BB.getTerminator()); + if (!CheckLoc) { + for (auto &Inst : BB) { + auto *CB = dyn_cast(&Inst); + if (!CB) + continue; + if (!CB->doesNotReturn()) + continue; + // Do stack check before non-return calls (e.g: __cxa_throw) + CheckLoc = CB; + RecalculateDT = true; + break; + } + } + + if (!CheckLoc) continue; // Generate prologue instrumentation if not already generated. if (!HasPrologue) { HasPrologue = true; - SupportsSelectionDAGSP &= CreatePrologue(F, M, RI, TLI, AI); + SupportsSelectionDAGSP &= CreatePrologue(F, M, CheckLoc, TLI, AI); } // SelectionDAG based code generation. Nothing else needs to be done here. @@ -476,8 +491,7 @@ // verifier guarantees that a tail call is either directly before the // return or with a single correct bitcast of the return value in between so // we don't need to worry about many situations here. - Instruction *CheckLoc = RI; - Instruction *Prev = RI->getPrevNonDebugInstruction(); + Instruction *Prev = CheckLoc->getPrevNonDebugInstruction(); if (Prev && isa(Prev) && cast(Prev)->isTailCall()) CheckLoc = Prev; else if (Prev) { @@ -533,12 +547,6 @@ BasicBlock *NewBB = BB.splitBasicBlock(CheckLoc->getIterator(), "SP_return"); - // Update the dominator tree if we need to. - if (DT && DT->isReachableFromEntry(&BB)) { - DT->addNewBlock(NewBB, &BB); - DT->addNewBlock(FailBB, &BB); - } - // Remove default branch instruction to the new BB. BB.getTerminator()->eraseFromParent(); @@ -559,6 +567,18 @@ .createBranchWeights(SuccessProb.getNumerator(), FailureProb.getNumerator()); B.CreateCondBr(Cmp, NewBB, FailBB, Weights); + + // Update the dominator tree if we need to. + if (DT && DT->isReachableFromEntry(&BB)) { + // For no return case there are may be other BBs success from + // the splited BB, we need recalculate the dominate tree. + if (RecalculateDT) { + DT->recalculate(*F); + } else { + DT->addNewBlock(NewBB, &BB); + DT->addNewBlock(FailBB, &BB); + } + } } } Index: llvm/test/CodeGen/X86/stack-protector-2.ll =================================================================== --- llvm/test/CodeGen/X86/stack-protector-2.ll +++ llvm/test/CodeGen/X86/stack-protector-2.ll @@ -192,4 +192,34 @@ ret void } +; Check stack protect for noreturn call +define dso_local i32 @foo_no_return(i32 %0) #1 { +; CHECK-LABEL: @foo_no_return +entry: + %cmp = icmp sgt i32 %0, 4 + br i1 %cmp, label %if.then, label %if.end + +; CHECK: if.then: ; preds = %entry +; CHECK-NEXT: %StackGuard1 = load volatile i8*, i8* addrspace(257)* inttoptr (i32 40 to i8* addrspace(257)*), align 8 +; CHECK-NEXT: %1 = load volatile i8*, i8** %StackGuardSlot, align 8 +; CHECK-NEXT: %2 = icmp eq i8* %StackGuard1, %1 +; CHECK-NEXT: br i1 %2, label %SP_return, label %CallStackCheckFailBlk +; CHECK: SP_return: ; preds = %if.then +; CHECK-NEXT: %call = call i32 @foo_no_return(i32 1) +; CHECK-NEXT: br label %return +; CHECK: if.end: ; preds = %entry +; CHECK-NEXT: br label %return + +if.then: ; preds = %entry + %call = call i32 @foo_no_return(i32 1) + br label %return + +if.end: ; preds = %entry + br label %return + +return: ; preds = %if.end, %if.then + ret i32 0 +} + attributes #0 = { sspstrong } +attributes #1 = { noreturn sspreq} Index: llvm/test/CodeGen/X86/stack-protector-no-return.ll =================================================================== --- /dev/null +++ llvm/test/CodeGen/X86/stack-protector-no-return.ll @@ -0,0 +1,194 @@ +; RUN: llc %s -mtriple=x86_64-unknown-linux-gnu -o - | FileCheck %s + +$__clang_call_terminate = comdat any + +@_ZTIi = external dso_local constant i8* +@.str = private unnamed_addr constant [5 x i8] c"win\0A\00", align 1 + +; Function Attrs: mustprogress noreturn sspreq uwtable +define dso_local void @_Z7catchesv() local_unnamed_addr #0 personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) { +; CHECK-LABEL: _Z7catchesv: +; CHECK: # %bb.0: # %entry +; CHECK: movq %fs:40, %rax +; CHECK-NEXT: movq %rax, 8(%rsp) +entry: + %exception = tail call i8* @__cxa_allocate_exception(i64 4) #8 + %0 = bitcast i8* %exception to i32* + store i32 1, i32* %0, align 16 + invoke void @__cxa_throw(i8* nonnull %exception, i8* bitcast (i8** @_ZTIi to i8*), i8* null) #9 + to label %unreachable unwind label %lpad + +; CHECK: callq __cxa_allocate_exception +; CHECK-NEXT: movl $1, (%rax) +; CHECK-NEXT: movq %fs:40, %rcx +; CHECK-NEXT: cmpq 8(%rsp), %rcx +; CHECK-NEXT: jne .LBB0_12 +; CHECK-NEXT: # %bb.1: # %SP_return +; CHECK-NEXT: .Ltmp0: +; CHECK-NEXT: movl $_ZTIi, %esi +; CHECK-NEXT: movq %rax, %rdi +; CHECK-NEXT: xorl %edx, %edx +; CHECK-NEXT: callq __cxa_throw + +lpad: ; preds = %entry + %1 = landingpad { i8*, i32 } + catch i8* null + %2 = extractvalue { i8*, i32 } %1, 0 + %3 = tail call i8* @__cxa_begin_catch(i8* %2) #8 + %call = invoke i64 @write(i32 noundef 1, i8* noundef getelementptr inbounds ([5 x i8], [5 x i8]* @.str, i64 0, i64 0), i64 noundef 4) + to label %invoke.cont unwind label %lpad1 +; CHECK: callq __cxa_begin_catch +; CHECK-NEXT: .Ltmp3: +; CHECK-NEXT: movl $.L.str, %esi +; CHECK-NEXT: movl $4, %edx +; CHECK-NEXT: movl $1, %edi +; CHECK-NEXT: callq write + + +invoke.cont: ; preds = %lpad + invoke void @_exit(i32 noundef 1) #9 + to label %invoke.cont2 unwind label %lpad1 +; CHECK: # %bb.3: # %invoke.cont +; CHECK-NEXT: movq %fs:40, %rax +; CHECK-NEXT: cmpq 8(%rsp), %rax +; CHECK-NEXT: jne .LBB0_12 +; CHECK-NEXT: # %bb.4: # %SP_return3 +; CHECK-NEXT: .Ltmp5: +; CHECK-NEXT: movl $1, %edi +; CHECK-NEXT: callq _exit + +invoke.cont2: ; preds = %invoke.cont + unreachable + +lpad1: ; preds = %invoke.cont, %lpad + %4 = landingpad { i8*, i32 } + cleanup + invoke void @__cxa_end_catch() + to label %eh.resume unwind label %terminate.lpad +; CHECK: .LBB0_6: # %lpad1 +; CHECK-NEXT: .Ltmp7: +; CHECK-NEXT: movq %rax, %rbx +; CHECK-NEXT: .Ltmp8: +; CHECK-NEXT: callq __cxa_end_catch + +eh.resume: ; preds = %lpad1 + resume { i8*, i32 } %4 +; CHECK: # %bb.7: # %eh.resume +; CHECK-NEXT: movq %fs:40, %rax +; CHECK-NEXT: cmpq 8(%rsp), %rax +; CHECK-NEXT: jne .LBB0_12 +; CHECK-NEXT: # %bb.8: # %SP_return6 +; CHECK-NEXT: movq %rbx, %rdi +; CHECK-NEXT: callq _Unwind_Resume@PLT + +terminate.lpad: ; preds = %lpad1 + %5 = landingpad { i8*, i32 } + catch i8* null + %6 = extractvalue { i8*, i32 } %5, 0 + tail call void @__clang_call_terminate(i8* %6) #10 + unreachable + +; CHECK: .LBB0_9: # %terminate.lpad +; CHECK: movq %fs:40, %rcx +; CHECK-NEXT: cmpq 8(%rsp), %rcx +; CHECK-NEXT: jne .LBB0_12 +; CHECK-NEXT: # %bb.10: # %SP_return9 +; CHECK-NEXT: movq %rax, %rdi +; CHECK-NEXT: callq __clang_call_terminate + +; CHECK: .LBB0_12: # %CallStackCheckFailBlk +; CHECK-NEXT: callq __stack_chk_fail@PLT + +unreachable: ; preds = %entry + unreachable +} + +; Function Attrs: nofree +declare dso_local noalias i8* @__cxa_allocate_exception(i64) local_unnamed_addr #1 + +; Function Attrs: nofree noreturn +declare dso_local void @__cxa_throw(i8*, i8*, i8*) local_unnamed_addr #2 + +declare dso_local i32 @__gxx_personality_v0(...) + +; Function Attrs: nofree +declare dso_local i8* @__cxa_begin_catch(i8*) local_unnamed_addr #1 + +; Function Attrs: nofree +declare dso_local noundef i64 @write(i32 noundef, i8* nocapture noundef readonly, i64 noundef) local_unnamed_addr #3 + +; Function Attrs: nofree noreturn +declare dso_local void @_exit(i32 noundef) local_unnamed_addr #4 + +; Function Attrs: nofree +declare dso_local void @__cxa_end_catch() local_unnamed_addr #1 + +; Function Attrs: noinline noreturn nounwind +define linkonce_odr hidden void @__clang_call_terminate(i8* %0) local_unnamed_addr #5 comdat { + %2 = tail call i8* @__cxa_begin_catch(i8* %0) #8 + tail call void @_ZSt9terminatev() #10 + unreachable +} + +; Function Attrs: nofree noreturn nounwind +declare dso_local void @_ZSt9terminatev() local_unnamed_addr #6 + +; Function Attrs: mustprogress nofree sspreq uwtable +define dso_local void @_Z4vulni(i32 noundef %op) local_unnamed_addr #7 { +; CHECK-LABEL: _Z4vulni: +; CHECK: # %bb.0: # %entry +; CHECK-NEXT: pushq %rax +; CHECK-NEXT: .cfi_def_cfa_offset 16 +; CHECK-NEXT: movq %fs:40, %rax +; CHECK-NEXT: movq %rax, (%rsp) +; CHECK-NEXT: cmpl $1, %edi +; CHECK-NEXT: je .LBB2_1 +; CHECK-NEXT: # %bb.3: # %if.end +; CHECK-NEXT: movq %fs:40, %rax +; CHECK-NEXT: cmpq (%rsp), %rax +; CHECK-NEXT: jne .LBB2_5 +; CHECK-NEXT: # %bb.4: # %SP_return3 +; CHECK-NEXT: popq %rax +; CHECK-NEXT: .cfi_def_cfa_offset 8 +; CHECK-NEXT: retq +; CHECK-NEXT: .LBB2_1: # %if.then +; CHECK-NEXT: .cfi_def_cfa_offset 16 +; CHECK-NEXT: movl $4, %edi +; CHECK-NEXT: callq __cxa_allocate_exception +; CHECK-NEXT: movl $1, (%rax) +; CHECK-NEXT: movq %fs:40, %rcx +; CHECK-NEXT: cmpq (%rsp), %rcx +; CHECK-NEXT: jne .LBB2_5 +; CHECK-NEXT: # %bb.2: # %SP_return +; CHECK-NEXT: movl $_ZTIi, %esi +; CHECK-NEXT: movq %rax, %rdi +; CHECK-NEXT: xorl %edx, %edx +; CHECK-NEXT: callq __cxa_throw +; CHECK-NEXT: .LBB2_5: # %CallStackCheckFailBlk2 +; CHECK-NEXT: callq __stack_chk_fail@PLT +entry: + %cmp = icmp eq i32 %op, 1 + br i1 %cmp, label %if.then, label %if.end + +if.then: ; preds = %entry + %exception = tail call i8* @__cxa_allocate_exception(i64 4) #8 + %0 = bitcast i8* %exception to i32* + store i32 1, i32* %0, align 16 + tail call void @__cxa_throw(i8* %exception, i8* bitcast (i8** @_ZTIi to i8*), i8* null) #9 + unreachable + +if.end: ; preds = %entry + ret void +} + +attributes #0 = { mustprogress noreturn sspreq uwtable } +attributes #1 = { nofree } +attributes #2 = { nofree noreturn } +attributes #3 = { nofree } +attributes #4 = { nofree noreturn } +attributes #5 = { noinline noreturn nounwind } +attributes #6 = { nofree noreturn nounwind } +attributes #7 = { mustprogress nofree sspreq uwtable } +attributes #8 = { nounwind } +attributes #9 = { noreturn } +attributes #10 = { noreturn nounwind }