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Diffstat (limited to 'test/Transforms/InstCombine/stacksaverestore.ll')
-rw-r--r-- | test/Transforms/InstCombine/stacksaverestore.ll | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/stacksaverestore.ll b/test/Transforms/InstCombine/stacksaverestore.ll new file mode 100644 index 000000000000..c82a425b2fd0 --- /dev/null +++ b/test/Transforms/InstCombine/stacksaverestore.ll @@ -0,0 +1,56 @@ +; RUN: llvm-as < %s | opt -instcombine | llvm-dis | 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) + |