; RUN: opt < %s -instcombine -S | grep "call.*stackrestore" | count 1 declare i8* @llvm.stacksave() declare void @llvm.stackrestore(i8*) ;; Test that llvm.stackrestore is removed when possible. define i32* @test1(i32 %P) { %tmp = call i8* @llvm.stacksave( ) call void @llvm.stackrestore( i8* %tmp ) ;; not restoring anything %A = alloca i32, i32 %P ret i32* %A } define void @test2(i8* %X) { call void @llvm.stackrestore( i8* %X ) ;; no allocas before return. ret void } define void @foo(i32 %size) nounwind { entry: %tmp118124 = icmp sgt i32 %size, 0 ; <i1> [#uses=1] br i1 %tmp118124, label %bb.preheader, label %return bb.preheader: ; preds = %entry %tmp25 = add i32 %size, -1 ; <i32> [#uses=1] %tmp125 = icmp slt i32 %size, 1 ; <i1> [#uses=1] %smax = select i1 %tmp125, i32 1, i32 %size ; <i32> [#uses=1] br label %bb bb: ; preds = %bb, %bb.preheader %i.0.reg2mem.0 = phi i32 [ 0, %bb.preheader ], [ %indvar.next, %bb ] ; <i32> [#uses=2] %tmp = call i8* @llvm.stacksave( ) ; <i8*> [#uses=1] %tmp23 = alloca i8, i32 %size ; <i8*> [#uses=2] %tmp27 = getelementptr i8* %tmp23, i32 %tmp25 ; <i8*> [#uses=1] store i8 0, i8* %tmp27, align 1 %tmp28 = call i8* @llvm.stacksave( ) ; <i8*> [#uses=1] %tmp52 = alloca i8, i32 %size ; <i8*> [#uses=1] %tmp53 = call i8* @llvm.stacksave( ) ; <i8*> [#uses=1] %tmp77 = alloca i8, i32 %size ; <i8*> [#uses=1] %tmp78 = call i8* @llvm.stacksave( ) ; <i8*> [#uses=1] %tmp102 = alloca i8, i32 %size ; <i8*> [#uses=1] call void @bar( i32 %i.0.reg2mem.0, i8* %tmp23, i8* %tmp52, i8* %tmp77, i8* %tmp102, i32 %size ) nounwind call void @llvm.stackrestore( i8* %tmp78 ) call void @llvm.stackrestore( i8* %tmp53 ) call void @llvm.stackrestore( i8* %tmp28 ) call void @llvm.stackrestore( i8* %tmp ) %indvar.next = add i32 %i.0.reg2mem.0, 1 ; <i32> [#uses=2] %exitcond = icmp eq i32 %indvar.next, %smax ; <i1> [#uses=1] br i1 %exitcond, label %return, label %bb return: ; preds = %bb, %entry ret void } declare void @bar(i32, i8*, i8*, i8*, i8*, i32)