1 ; This test makes sure that these instructions are properly eliminated. 2 ; 3 ; RUN: opt < %s -instcombine -S | FileCheck %s 4 5 ; PR1253 6 define i1 @test0(i32 %A) { 7 ; CHECK-LABEL: @test0( 8 ; CHECK: %C = icmp slt i32 %A, 0 9 %B = xor i32 %A, -2147483648 10 %C = icmp sgt i32 %B, -1 11 ret i1 %C 12 } 13 14 define i1 @test1(i32 %A) { 15 ; CHECK-LABEL: @test1( 16 ; CHECK: %C = icmp slt i32 %A, 0 17 %B = xor i32 %A, 12345 18 %C = icmp slt i32 %B, 0 19 ret i1 %C 20 } 21 22 ; PR1014 23 define i32 @test2(i32 %tmp1) { 24 ; CHECK-LABEL: @test2( 25 ; CHECK-NEXT: and i32 %tmp1, 32 26 ; CHECK-NEXT: or i32 %ovm, 8 27 ; CHECK-NEXT: ret i32 28 %ovm = and i32 %tmp1, 32 29 %ov3 = add i32 %ovm, 145 30 %ov110 = xor i32 %ov3, 153 31 ret i32 %ov110 32 } 33 34 define i32 @test3(i32 %tmp1) { 35 ; CHECK-LABEL: @test3( 36 ; CHECK-NEXT: and i32 %tmp1, 32 37 ; CHECK-NEXT: or i32 %ovm, 8 38 ; CHECK-NEXT: ret i32 39 %ovm = or i32 %tmp1, 145 40 %ov31 = and i32 %ovm, 177 41 %ov110 = xor i32 %ov31, 153 42 ret i32 %ov110 43 } 44 45 define i32 @test4(i32 %A, i32 %B) { 46 %1 = xor i32 %A, -1 47 %2 = ashr i32 %1, %B 48 %3 = xor i32 %2, -1 49 ret i32 %3 50 ; CHECK-LABEL: @test4( 51 ; CHECK: %1 = ashr i32 %A, %B 52 ; CHECK: ret i32 %1 53 } 54 55 ; defect-2 in rdar://12329730 56 ; (X^C1) >> C2) ^ C3 -> (X>>C2) ^ ((C1>>C2)^C3) 57 ; where the "X" has more than one use 58 define i32 @test5(i32 %val1) { 59 test5: 60 %xor = xor i32 %val1, 1234 61 %shr = lshr i32 %xor, 8 62 %xor1 = xor i32 %shr, 1 63 %add = add i32 %xor1, %xor 64 ret i32 %add 65 ; CHECK-LABEL: @test5( 66 ; CHECK: lshr i32 %val1, 8 67 ; CHECK: ret 68 } 69 70 ; defect-1 in rdar://12329730 71 ; Simplify (X^Y) -> X or Y in the user's context if we know that 72 ; only bits from X or Y are demanded. 73 ; e.g. the "x ^ 1234" can be optimized into x in the context of "t >> 16". 74 ; Put in other word, t >> 16 -> x >> 16. 75 ; unsigned foo(unsigned x) { unsigned t = x ^ 1234; ; return (t >> 16) + t;} 76 define i32 @test6(i32 %x) { 77 %xor = xor i32 %x, 1234 78 %shr = lshr i32 %xor, 16 79 %add = add i32 %shr, %xor 80 ret i32 %add 81 ; CHECK-LABEL: @test6( 82 ; CHECK: lshr i32 %x, 16 83 ; CHECK: ret 84 } 85
