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| author | Chris Lattner <sabre@nondot.org> | 2008-12-15 07:49:24 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2008-12-15 07:49:24 +0000 |
| commit | a8ff424f81084d6480490952219d6146f8ee0d5e (patch) | |
| tree | f45274d8895928384fc9d956a038f7d449b758bd /test/Transforms/GVN/lpre-call-wrap-2.ll | |
| parent | e2c0e0fa729ac1c3a9dc6aec53d838d79fa616fb (diff) | |
| download | external_llvm-a8ff424f81084d6480490952219d6146f8ee0d5e.zip external_llvm-a8ff424f81084d6480490952219d6146f8ee0d5e.tar.gz external_llvm-a8ff424f81084d6480490952219d6146f8ee0d5e.tar.bz2 | |
Add a testcase for GCC PR 23455, which lpre handles now. Add some
comments about why we're not getting other cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61032 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test/Transforms/GVN/lpre-call-wrap-2.ll')
| -rw-r--r-- | test/Transforms/GVN/lpre-call-wrap-2.ll | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/test/Transforms/GVN/lpre-call-wrap-2.ll b/test/Transforms/GVN/lpre-call-wrap-2.ll new file mode 100644 index 0000000..c9f9352 --- /dev/null +++ b/test/Transforms/GVN/lpre-call-wrap-2.ll @@ -0,0 +1,39 @@ +; RUN: llvm-as < %s | opt -gvn -enable-load-pre | llvm-dis > %t +; RUN: %prcontext bb1: 2 < %t | grep phi +; RUN: %prcontext bb1: 2 < %t | not grep load +; +; The partially redundant load in bb1 should be hoisted to "bb". This comes +; from this C code (GCC PR 23455): +; unsigned outcnt; extern void flush_outbuf(void); +; void bi_windup(unsigned char *outbuf, unsigned char bi_buf) { +; outbuf[outcnt] = bi_buf; +; if (outcnt == 16384) +; flush_outbuf(); +; outbuf[outcnt] = bi_buf; +; } +target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128" +target triple = "i386-apple-darwin7" +@outcnt = common global i32 0 ; <i32*> [#uses=3] + +define void @bi_windup(i8* %outbuf, i8 zeroext %bi_buf) nounwind { +entry: + %"alloca point" = bitcast i32 0 to i32 ; <i32> [#uses=0] + %0 = load i32* @outcnt, align 4 ; <i32> [#uses=1] + %1 = getelementptr i8* %outbuf, i32 %0 ; <i8*> [#uses=1] + store i8 %bi_buf, i8* %1, align 1 + %2 = load i32* @outcnt, align 4 ; <i32> [#uses=1] + %3 = icmp eq i32 %2, 16384 ; <i1> [#uses=1] + br i1 %3, label %bb, label %bb1 + +bb: ; preds = %entry + call void @flush_outbuf() nounwind + br label %bb1 + +bb1: ; preds = %bb, %entry + %4 = load i32* @outcnt, align 4 ; <i32> [#uses=1] + %5 = getelementptr i8* %outbuf, i32 %4 ; <i8*> [#uses=1] + store i8 %bi_buf, i8* %5, align 1 + ret void +} + +declare void @flush_outbuf() |