1 ; This file contains various testcases that check to see that instcombine 2 ; is narrowing computations when possible. 3 ; RUN: opt < %s -instcombine -S | \ 4 ; RUN: grep "ret i1 false" 5 6 ; test1 - Eliminating the casts in this testcase (by narrowing the AND 7 ; operation) allows instcombine to realize the function always returns false. 8 ; 9 define i1 @test1(i32 %A, i32 %B) { 10 %C1 = icmp slt i32 %A, %B ; <i1> [#uses=1] 11 %ELIM1 = zext i1 %C1 to i32 ; <i32> [#uses=1] 12 %C2 = icmp sgt i32 %A, %B ; <i1> [#uses=1] 13 %ELIM2 = zext i1 %C2 to i32 ; <i32> [#uses=1] 14 %C3 = and i32 %ELIM1, %ELIM2 ; <i32> [#uses=1] 15 %ELIM3 = trunc i32 %C3 to i1 ; <i1> [#uses=1] 16 ret i1 %ELIM3 17 } 18 19