llvm-6502/test/Transforms/InstCombine/narrow.ll

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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
}