forked from OSchip/llvm-project
19 lines
788 B
LLVM
19 lines
788 B
LLVM
; This file contains various testcases that check to see that instcombine
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; is narrowing computations when possible.
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; RUN: opt < %s -instcombine -S | \
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; RUN: grep {ret i1 false}
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; test1 - Eliminating the casts in this testcase (by narrowing the AND
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; operation) allows instcombine to realize the function always returns false.
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;
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define i1 @test1(i32 %A, i32 %B) {
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%C1 = icmp slt i32 %A, %B ; <i1> [#uses=1]
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%ELIM1 = zext i1 %C1 to i32 ; <i32> [#uses=1]
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%C2 = icmp sgt i32 %A, %B ; <i1> [#uses=1]
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%ELIM2 = zext i1 %C2 to i32 ; <i32> [#uses=1]
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%C3 = and i32 %ELIM1, %ELIM2 ; <i32> [#uses=1]
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%ELIM3 = trunc i32 %C3 to i1 ; <i1> [#uses=1]
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ret i1 %ELIM3
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}
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