Mercurial > hg > CbC > CbC_llvm
view test/Transforms/InstCombine/narrow.ll @ 0:95c75e76d11b LLVM3.4
LLVM 3.4
author | Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> |
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date | Thu, 12 Dec 2013 13:56:28 +0900 |
parents | |
children | 803732b1fca8 |
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; 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 }