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Diffstat (limited to 'test/Transforms/InstCombine/preserve-sminmax.ll')
-rw-r--r-- | test/Transforms/InstCombine/preserve-sminmax.ll | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/preserve-sminmax.ll b/test/Transforms/InstCombine/preserve-sminmax.ll new file mode 100644 index 0000000..24fb7da --- /dev/null +++ b/test/Transforms/InstCombine/preserve-sminmax.ll @@ -0,0 +1,22 @@ +; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep { i32 \[%\]sd, \[\[:alnum:\]\]* \\?1\\>} | count 4 + +; Instcombine normally would fold the sdiv into the comparison, +; making "icmp slt i32 %h, 2", but in this case the sdiv has +; another use, so it wouldn't a big win, and it would also +; obfuscate an otherise obvious smax pattern to the point where +; other analyses wouldn't recognize it. + +define i32 @foo(i32 %h) { + %sd = sdiv i32 %h, 2 + %t = icmp slt i32 %sd, 1 + %r = select i1 %t, i32 %sd, i32 1 + ret i32 %r +} + +define i32 @bar(i32 %h) { + %sd = sdiv i32 %h, 2 + %t = icmp sgt i32 %sd, 1 + %r = select i1 %t, i32 %sd, i32 1 + ret i32 %r +} + |