; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt -instcombine -S < %s | FileCheck %s ; PR5438 ; TODO: This should also optimize down. ;define i32 @test1(i32 %a, i32 %b) nounwind readnone { ;entry: ; %0 = icmp sgt i32 %a, -1 ; %1 = icmp slt i32 %b, 0 ; %2 = xor i1 %1, %0 ; %3 = zext i1 %2 to i32 ; ret i32 %3 ;} ; TODO: This optimizes partially but not all the way. ;define i32 @test2(i32 %a, i32 %b) nounwind readnone { ;entry: ; %0 = and i32 %a, 8 ; %1 = and i32 %b, 8 ; %2 = icmp eq i32 %0, %1 ; %3 = zext i1 %2 to i32 ; ret i32 %3 ;} define i32 @test3(i32 %a, i32 %b) nounwind readnone { ; CHECK-LABEL: @test3( ; CHECK-NEXT: [[T2_UNSHIFTED:%.*]] = xor i32 %a, %b ; CHECK-NEXT: [[T2_UNSHIFTED_LOBIT:%.*]] = lshr i32 [[T2_UNSHIFTED]], 31 ; CHECK-NEXT: [[T2_UNSHIFTED_LOBIT_NOT:%.*]] = xor i32 [[T2_UNSHIFTED_LOBIT]], 1 ; CHECK-NEXT: ret i32 [[T2_UNSHIFTED_LOBIT_NOT]] ; %t0 = lshr i32 %a, 31 %t1 = lshr i32 %b, 31 %t2 = icmp eq i32 %t0, %t1 %t3 = zext i1 %t2 to i32 ret i32 %t3 } ; Variation on @test3: checking the 2nd bit in a situation where the 5th bit ; is one, not zero. define i32 @test3i(i32 %a, i32 %b) nounwind readnone { ; CHECK-LABEL: @test3i( ; CHECK-NEXT: [[T01:%.*]] = xor i32 %a, %b ; CHECK-NEXT: [[TMP1:%.*]] = lshr i32 [[T01]], 31 ; CHECK-NEXT: [[T4:%.*]] = xor i32 [[TMP1]], 1 ; CHECK-NEXT: ret i32 [[T4]] ; %t0 = lshr i32 %a, 29 %t1 = lshr i32 %b, 29 %t2 = or i32 %t0, 35 %t3 = or i32 %t1, 35 %t4 = icmp eq i32 %t2, %t3 %t5 = zext i1 %t4 to i32 ret i32 %t5 } define i1 @test4a(i32 %a) { ; CHECK-LABEL: @test4a( ; CHECK-NEXT: [[C:%.*]] = icmp slt i32 %a, 1 ; CHECK-NEXT: ret i1 [[C]] ; %l = ashr i32 %a, 31 %na = sub i32 0, %a %r = lshr i32 %na, 31 %signum = or i32 %l, %r %c = icmp slt i32 %signum, 1 ret i1 %c } define i1 @test4b(i64 %a) { ; CHECK-LABEL: @test4b( ; CHECK-NEXT: [[C:%.*]] = icmp slt i64 %a, 1 ; CHECK-NEXT: ret i1 [[C]] ; %l = ashr i64 %a, 63 %na = sub i64 0, %a %r = lshr i64 %na, 63 %signum = or i64 %l, %r %c = icmp slt i64 %signum, 1 ret i1 %c } define i1 @test4c(i64 %a) { ; CHECK-LABEL: @test4c( ; CHECK-NEXT: [[C:%.*]] = icmp slt i64 %a, 1 ; CHECK-NEXT: ret i1 [[C]] ; %l = ashr i64 %a, 63 %na = sub i64 0, %a %r = lshr i64 %na, 63 %signum = or i64 %l, %r %signum.trunc = trunc i64 %signum to i32 %c = icmp slt i32 %signum.trunc, 1 ret i1 %c }