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| author | Owen Anderson <resistor@mac.com> | 2010-12-21 23:54:34 +0000 |
|---|---|---|
| committer | Owen Anderson <resistor@mac.com> | 2010-12-21 23:54:34 +0000 |
| commit | f0568389563d46a7252ce8a17ef316e313cc17c6 (patch) | |
| tree | 9b02598fc1a44c967ae76446eb20d6a14a3d8fec /test/Transforms/GVN | |
| parent | e733cf8c2743acf0e4bee4952dfb013de6257478 (diff) | |
| download | llvm-f0568389563d46a7252ce8a17ef316e313cc17c6.tar.gz llvm-f0568389563d46a7252ce8a17ef316e313cc17c6.tar.bz2 llvm-f0568389563d46a7252ce8a17ef316e313cc17c6.tar.xz | |
Give GVN back the ability to perform simple conditional propagation on conditional branch values.
I still think that LVI should be handling this, but that capability is some ways off in the future,
and this matters for some significant benchmarks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122378 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test/Transforms/GVN')
| -rw-r--r-- | test/Transforms/GVN/condprop.ll | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/test/Transforms/GVN/condprop.ll b/test/Transforms/GVN/condprop.ll new file mode 100644 index 0000000000..be6c3498fe --- /dev/null +++ b/test/Transforms/GVN/condprop.ll @@ -0,0 +1,55 @@ +; RUN: opt < %s -basicaa -gvn -S | FileCheck %s + +@a = external global i32 ; <i32*> [#uses=7] + +; CHECK: @foo +define i32 @foo() nounwind { +entry: + %0 = load i32* @a, align 4 + %1 = icmp eq i32 %0, 4 + br i1 %1, label %bb, label %bb1 + +bb: ; preds = %entry + br label %bb8 + +bb1: ; preds = %entry + %2 = load i32* @a, align 4 + %3 = icmp eq i32 %2, 5 + br i1 %3, label %bb2, label %bb3 + +bb2: ; preds = %bb1 + br label %bb8 + +bb3: ; preds = %bb1 + %4 = load i32* @a, align 4 + %5 = icmp eq i32 %4, 4 +; CHECK: br i1 false, label %bb4, label %bb5 + br i1 %5, label %bb4, label %bb5 + +bb4: ; preds = %bb3 + %6 = load i32* @a, align 4 + %7 = add i32 %6, 5 + br label %bb8 + +bb5: ; preds = %bb3 + %8 = load i32* @a, align 4 + %9 = icmp eq i32 %8, 5 +; CHECK: br i1 false, label %bb6, label %bb7 + br i1 %9, label %bb6, label %bb7 + +bb6: ; preds = %bb5 + %10 = load i32* @a, align 4 + %11 = add i32 %10, 4 + br label %bb8 + +bb7: ; preds = %bb5 + %12 = load i32* @a, align 4 + br label %bb8 + +bb8: ; preds = %bb7, %bb6, %bb4, %bb2, %bb + %.0 = phi i32 [ %12, %bb7 ], [ %11, %bb6 ], [ %7, %bb4 ], [ 4, %bb2 ], [ 5, %bb ] + br label %return + +return: ; preds = %bb8 + ret i32 %.0 +}
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