; This test makes sure that these instructions are properly eliminated. ; ; RUN: opt < %s -instcombine -S | FileCheck %s ; PR1253 define i1 @test0(i32 %A) { ; CHECK-LABEL: @test0( ; CHECK: %C = icmp slt i32 %A, 0 %B = xor i32 %A, -2147483648 %C = icmp sgt i32 %B, -1 ret i1 %C } define i1 @test1(i32 %A) { ; CHECK-LABEL: @test1( ; CHECK: %C = icmp slt i32 %A, 0 %B = xor i32 %A, 12345 %C = icmp slt i32 %B, 0 ret i1 %C } ; PR1014 define i32 @test2(i32 %tmp1) { ; CHECK-LABEL: @test2( ; CHECK-NEXT: and i32 %tmp1, 32 ; CHECK-NEXT: or i32 %ovm, 8 ; CHECK-NEXT: ret i32 %ovm = and i32 %tmp1, 32 %ov3 = add i32 %ovm, 145 %ov110 = xor i32 %ov3, 153 ret i32 %ov110 } define i32 @test3(i32 %tmp1) { ; CHECK-LABEL: @test3( ; CHECK-NEXT: and i32 %tmp1, 32 ; CHECK-NEXT: or i32 %ovm, 8 ; CHECK-NEXT: ret i32 %ovm = or i32 %tmp1, 145 %ov31 = and i32 %ovm, 177 %ov110 = xor i32 %ov31, 153 ret i32 %ov110 } define i32 @test4(i32 %A, i32 %B) { %1 = xor i32 %A, -1 %2 = ashr i32 %1, %B %3 = xor i32 %2, -1 ret i32 %3 ; CHECK-LABEL: @test4( ; CHECK: %1 = ashr i32 %A, %B ; CHECK: ret i32 %1 } ; defect-2 in rdar://12329730 ; (X^C1) >> C2) ^ C3 -> (X>>C2) ^ ((C1>>C2)^C3) ; where the "X" has more than one use define i32 @test5(i32 %val1) { test5: %xor = xor i32 %val1, 1234 %shr = lshr i32 %xor, 8 %xor1 = xor i32 %shr, 1 %add = add i32 %xor1, %xor ret i32 %add ; CHECK-LABEL: @test5( ; CHECK: lshr i32 %val1, 8 ; CHECK: ret } ; defect-1 in rdar://12329730 ; Simplify (X^Y) -> X or Y in the user's context if we know that ; only bits from X or Y are demanded. ; e.g. the "x ^ 1234" can be optimized into x in the context of "t >> 16". ; Put in other word, t >> 16 -> x >> 16. ; unsigned foo(unsigned x) { unsigned t = x ^ 1234; ; return (t >> 16) + t;} define i32 @test6(i32 %x) { %xor = xor i32 %x, 1234 %shr = lshr i32 %xor, 16 %add = add i32 %shr, %xor ret i32 %add ; CHECK-LABEL: @test6( ; CHECK: lshr i32 %x, 16 ; CHECK: ret }