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author | Christopher Lamb <christopher.lamb@gmail.com> | 2007-12-18 09:34:41 +0000 |
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committer | Christopher Lamb <christopher.lamb@gmail.com> | 2007-12-18 09:34:41 +0000 |
commit | 30f017ad898bd86415aab001b45b5ac1373fa882 (patch) | |
tree | 684d8145ff886cb254534894638de7e7b309f769 /test/Transforms/InstCombine/2007-12-18-AddSelCmpSub.ll | |
parent | beec823d4bba22b1c0c6658d2b3e71cd64a70e2e (diff) | |
download | llvm-30f017ad898bd86415aab001b45b5ac1373fa882.tar.gz llvm-30f017ad898bd86415aab001b45b5ac1373fa882.tar.bz2 llvm-30f017ad898bd86415aab001b45b5ac1373fa882.tar.xz |
Fold certain additions through selects (and their compares) so as to eliminate subtractions. This code is often produced by the SMAX expansion in SCEV.
This implements test/Transforms/InstCombine/2007-12-18-AddSelCmpSub.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45158 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test/Transforms/InstCombine/2007-12-18-AddSelCmpSub.ll')
-rw-r--r-- | test/Transforms/InstCombine/2007-12-18-AddSelCmpSub.ll | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/2007-12-18-AddSelCmpSub.ll b/test/Transforms/InstCombine/2007-12-18-AddSelCmpSub.ll new file mode 100644 index 0000000000..ef38eee30e --- /dev/null +++ b/test/Transforms/InstCombine/2007-12-18-AddSelCmpSub.ll @@ -0,0 +1,38 @@ +; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep {sub} + +define i32 @foo(i32 %a) { +entry: + %tmp15 = sub i32 99, %a ; <i32> [#uses=2] + %tmp16 = icmp slt i32 %tmp15, 0 ; <i1> [#uses=1] + %smax = select i1 %tmp16, i32 0, i32 %tmp15 ; <i32> [#uses=1] + %tmp12 = add i32 %smax, %a ; <i32> [#uses=1] + %tmp13 = add i32 %tmp12, 1 ; <i32> [#uses=1] + ret i32 %tmp13 +} + +define i32 @bar(i32 %a) { +entry: + %tmp15 = sub i32 99, %a ; <i32> [#uses=2] + %tmp16 = icmp slt i32 %tmp15, 0 ; <i1> [#uses=1] + %smax = select i1 %tmp16, i32 0, i32 %tmp15 ; <i32> [#uses=1] + %tmp12 = add i32 %smax, %a ; <i32> [#uses=1] + ret i32 %tmp12 +} + +define i32 @baz(i32 %a) { +entry: + %tmp15 = sub i32 99, %a ; <i32> [#uses=1] + %tmp16 = icmp slt i32 %tmp15, 0 ; <i1> [#uses=1] + %smax = select i1 %tmp16, i32 0, i32 42 ; <i32> [#uses=1] + %tmp12 = add i32 %smax, %a ; <i32> [#uses=1] + ret i32 %tmp12 +} + +define i32 @fun(i32 %a) { +entry: + %tmp15 = sub i32 99, %a ; <i32> [#uses=1] + %tmp16 = icmp slt i32 %a, 0 ; <i1> [#uses=1] + %smax = select i1 %tmp16, i32 0, i32 %tmp15 ; <i32> [#uses=1] + %tmp12 = add i32 %smax, %a ; <i32> [#uses=1] + ret i32 %tmp12 +}
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