; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt -instcombine -S < %s | FileCheck %s ; PR5438 define i32 @test1(i32 %a, i32 %b) nounwind readnone { ; CHECK-LABEL: @test1( ; CHECK-NEXT: [[TMP1:%.*]] = xor i32 [[B:%.*]], [[A:%.*]] ; CHECK-NEXT: [[TMP2:%.*]] = xor i32 [[TMP1]], -1 ; CHECK-NEXT: [[DOTLOBIT_NOT:%.*]] = lshr i32 [[TMP2]], 31 ; CHECK-NEXT: ret i32 [[DOTLOBIT_NOT]] ; %t0 = icmp sgt i32 %a, -1 %t1 = icmp slt i32 %b, 0 %t2 = xor i1 %t1, %t0 %t3 = zext i1 %t2 to i32 ret i32 %t3 } ; TODO: This optimizes partially but not all the way. define i32 @test2(i32 %a, i32 %b) nounwind readnone { ; CHECK-LABEL: @test2( ; CHECK-NEXT: [[TMP1:%.*]] = xor i32 [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[TMP2:%.*]] = lshr i32 [[TMP1]], 3 ; CHECK-NEXT: [[DOTLOBIT:%.*]] = and i32 [[TMP2]], 1 ; CHECK-NEXT: [[TMP3:%.*]] = xor i32 [[DOTLOBIT]], 1 ; CHECK-NEXT: ret i32 [[TMP3]] ; %t0 = and i32 %a, 8 %t1 = and i32 %b, 8 %t2 = icmp eq i32 %t0, %t1 %t3 = zext i1 %t2 to i32 ret i32 %t3 } define i32 @test3(i32 %a, i32 %b) nounwind readnone { ; CHECK-LABEL: @test3( ; CHECK-NEXT: [[T2_UNSHIFTED:%.*]] = xor i32 [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[TMP1:%.*]] = xor i32 [[T2_UNSHIFTED]], -1 ; CHECK-NEXT: [[T2_UNSHIFTED_LOBIT_NOT:%.*]] = lshr i32 [[TMP1]], 31 ; 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 } ; TODO this should optimize but doesn't due to missing vector support in InstCombiner::foldICmpEquality. define <2 x i32> @test3vec(<2 x i32> %a, <2 x i32> %b) nounwind readnone { ; CHECK-LABEL: @test3vec( ; CHECK-NEXT: [[T0:%.*]] = lshr <2 x i32> [[A:%.*]], ; CHECK-NEXT: [[T1:%.*]] = lshr <2 x i32> [[B:%.*]], ; CHECK-NEXT: [[T2:%.*]] = icmp eq <2 x i32> [[T0]], [[T1]] ; CHECK-NEXT: [[T3:%.*]] = zext <2 x i1> [[T2]] to <2 x i32> ; CHECK-NEXT: ret <2 x i32> [[T3]] ; %t0 = lshr <2 x i32> %a, %t1 = lshr <2 x i32> %b, %t2 = icmp eq <2 x i32> %t0, %t1 %t3 = zext <2 x i1> %t2 to <2 x i32> ret <2 x 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:%.*]] = xor i32 [[T01]], -1 ; CHECK-NEXT: [[T4:%.*]] = lshr i32 [[TMP1]], 31 ; 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 <2 x i1> @test4a_vec(<2 x i32> %a) { ; CHECK-LABEL: @test4a_vec( ; CHECK-NEXT: [[C:%.*]] = icmp slt <2 x i32> [[A:%.*]], ; CHECK-NEXT: ret <2 x i1> [[C]] ; %l = ashr <2 x i32> %a, %na = sub <2 x i32> zeroinitializer, %a %r = lshr <2 x i32> %na, %signum = or <2 x i32> %l, %r %c = icmp slt <2 x i32> %signum, ret <2 x 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 } define <2 x i1> @test4c_vec(<2 x i64> %a) { ; CHECK-LABEL: @test4c_vec( ; CHECK-NEXT: [[C:%.*]] = icmp slt <2 x i64> [[A:%.*]], ; CHECK-NEXT: ret <2 x i1> [[C]] ; %l = ashr <2 x i64> %a, %na = sub <2 x i64> zeroinitializer, %a %r = lshr <2 x i64> %na, %signum = or <2 x i64> %l, %r %signum.trunc = trunc <2 x i64> %signum to <2 x i32> %c = icmp slt <2 x i32> %signum.trunc, ret <2 x i1> %c }