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Diffstat (limited to 'test/Transforms/InstCombine/narrow.ll')
| -rw-r--r-- | test/Transforms/InstCombine/narrow.ll | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/narrow.ll b/test/Transforms/InstCombine/narrow.ll new file mode 100644 index 0000000..1b96a06 --- /dev/null +++ b/test/Transforms/InstCombine/narrow.ll @@ -0,0 +1,18 @@ +; This file contains various testcases that check to see that instcombine +; is narrowing computations when possible. +; RUN: opt < %s -instcombine -S | \ +; RUN: grep {ret i1 false} + +; test1 - Eliminating the casts in this testcase (by narrowing the AND +; operation) allows instcombine to realize the function always returns false. +; +define i1 @test1(i32 %A, i32 %B) { + %C1 = icmp slt i32 %A, %B ; <i1> [#uses=1] + %ELIM1 = zext i1 %C1 to i32 ; <i32> [#uses=1] + %C2 = icmp sgt i32 %A, %B ; <i1> [#uses=1] + %ELIM2 = zext i1 %C2 to i32 ; <i32> [#uses=1] + %C3 = and i32 %ELIM1, %ELIM2 ; <i32> [#uses=1] + %ELIM3 = trunc i32 %C3 to i1 ; <i1> [#uses=1] + ret i1 %ELIM3 +} + |