; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -passes=instcombine -S | FileCheck %s ; https://bugs.llvm.org/show_bug.cgi?id=38149 ; Pattern: ; ((%x << MaskedBits) a>> MaskedBits) != %x ; Should be transformed into: ; (add %x, (1 << (KeptBits-1))) u>= (1 << KeptBits) ; Where KeptBits = bitwidth(%x) - MaskedBits ; ============================================================================ ; ; Basic positive tests ; ============================================================================ ; define i1 @p0(i8 %x) { ; CHECK-LABEL: @p0( ; CHECK-NEXT: [[TMP1:%.*]] = add i8 [[X:%.*]], -4 ; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i8 [[TMP1]], -8 ; CHECK-NEXT: ret i1 [[TMP2]] ; %tmp0 = shl i8 %x, 5 %tmp1 = ashr exact i8 %tmp0, 5 %tmp2 = icmp ne i8 %tmp1, %x ret i1 %tmp2 } ; Big unusual bit width, https://bugs.llvm.org/show_bug.cgi?id=38204 define i1 @pb(i65 %x) { ; CHECK-LABEL: @pb( ; CHECK-NEXT: [[TMP1:%.*]] = add i65 [[X:%.*]], 9223372036854775808 ; CHECK-NEXT: [[TMP2:%.*]] = icmp slt i65 [[TMP1]], 0 ; CHECK-NEXT: ret i1 [[TMP2]] ; %tmp0 = shl i65 %x, 1 %tmp1 = ashr exact i65 %tmp0, 1 %tmp2 = icmp ne i65 %x, %tmp1 ret i1 %tmp2 } ; ============================================================================ ; ; Vector tests ; ============================================================================ ; define <2 x i1> @p1_vec_splat(<2 x i8> %x) { ; CHECK-LABEL: @p1_vec_splat( ; CHECK-NEXT: [[TMP1:%.*]] = add <2 x i8> [[X:%.*]], <i8 -4, i8 -4> ; CHECK-NEXT: [[TMP2:%.*]] = icmp ult <2 x i8> [[TMP1]], <i8 -8, i8 -8> ; CHECK-NEXT: ret <2 x i1> [[TMP2]] ; %tmp0 = shl <2 x i8> %x, <i8 5, i8 5> %tmp1 = ashr exact <2 x i8> %tmp0, <i8 5, i8 5> %tmp2 = icmp ne <2 x i8> %tmp1, %x ret <2 x i1> %tmp2 } define <2 x i1> @p2_vec_nonsplat(<2 x i8> %x) { ; CHECK-LABEL: @p2_vec_nonsplat( ; CHECK-NEXT: [[TMP0:%.*]] = shl <2 x i8> [[X:%.*]], <i8 5, i8 6> ; CHECK-NEXT: [[TMP1:%.*]] = ashr exact <2 x i8> [[TMP0]], <i8 5, i8 6> ; CHECK-NEXT: [[TMP2:%.*]] = icmp ne <2 x i8> [[TMP1]], [[X]] ; CHECK-NEXT: ret <2 x i1> [[TMP2]] ; %tmp0 = shl <2 x i8> %x, <i8 5, i8 6> %tmp1 = ashr exact <2 x i8> %tmp0, <i8 5, i8 6> %tmp2 = icmp ne <2 x i8> %tmp1, %x ret <2 x i1> %tmp2 } define <3 x i1> @p3_vec_undef0(<3 x i8> %x) { ; CHECK-LABEL: @p3_vec_undef0( ; CHECK-NEXT: [[TMP0:%.*]] = shl <3 x i8> [[X:%.*]], <i8 5, i8 undef, i8 5> ; CHECK-NEXT: [[TMP1:%.*]] = ashr exact <3 x i8> [[TMP0]], <i8 5, i8 5, i8 5> ; CHECK-NEXT: [[TMP2:%.*]] = icmp ne <3 x i8> [[TMP1]], [[X]] ; CHECK-NEXT: ret <3 x i1> [[TMP2]] ; %tmp0 = shl <3 x i8> %x, <i8 5, i8 undef, i8 5> %tmp1 = ashr exact <3 x i8> %tmp0, <i8 5, i8 5, i8 5> %tmp2 = icmp ne <3 x i8> %tmp1, %x ret <3 x i1> %tmp2 } define <3 x i1> @p4_vec_undef1(<3 x i8> %x) { ; CHECK-LABEL: @p4_vec_undef1( ; CHECK-NEXT: [[TMP0:%.*]] = shl <3 x i8> [[X:%.*]], <i8 5, i8 5, i8 5> ; CHECK-NEXT: [[TMP1:%.*]] = ashr exact <3 x i8> [[TMP0]], <i8 5, i8 undef, i8 5> ; CHECK-NEXT: [[TMP2:%.*]] = icmp ne <3 x i8> [[TMP1]], [[X]] ; CHECK-NEXT: ret <3 x i1> [[TMP2]] ; %tmp0 = shl <3 x i8> %x, <i8 5, i8 5, i8 5> %tmp1 = ashr exact <3 x i8> %tmp0, <i8 5, i8 undef, i8 5> %tmp2 = icmp ne <3 x i8> %tmp1, %x ret <3 x i1> %tmp2 } define <3 x i1> @p5_vec_undef2(<3 x i8> %x) { ; CHECK-LABEL: @p5_vec_undef2( ; CHECK-NEXT: [[TMP0:%.*]] = shl <3 x i8> [[X:%.*]], <i8 5, i8 undef, i8 5> ; CHECK-NEXT: [[TMP1:%.*]] = ashr exact <3 x i8> [[TMP0]], <i8 5, i8 undef, i8 5> ; CHECK-NEXT: [[TMP2:%.*]] = icmp ne <3 x i8> [[TMP1]], [[X]] ; CHECK-NEXT: ret <3 x i1> [[TMP2]] ; %tmp0 = shl <3 x i8> %x, <i8 5, i8 undef, i8 5> %tmp1 = ashr exact <3 x i8> %tmp0, <i8 5, i8 undef, i8 5> %tmp2 = icmp ne <3 x i8> %tmp1, %x ret <3 x i1> %tmp2 } ; ============================================================================ ; ; Commutativity tests. ; ============================================================================ ; declare i8 @gen8() define i1 @c0() { ; CHECK-LABEL: @c0( ; CHECK-NEXT: [[X:%.*]] = call i8 @gen8() ; CHECK-NEXT: [[TMP1:%.*]] = add i8 [[X]], -4 ; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i8 [[TMP1]], -8 ; CHECK-NEXT: ret i1 [[TMP2]] ; %x = call i8 @gen8() %tmp0 = shl i8 %x, 5 %tmp1 = ashr exact i8 %tmp0, 5 %tmp2 = icmp ne i8 %x, %tmp1 ; swapped order ret i1 %tmp2 } ; ============================================================================ ; ; One-use tests. ; ============================================================================ ; declare void @use8(i8) define i1 @n_oneuse0(i8 %x) { ; CHECK-LABEL: @n_oneuse0( ; CHECK-NEXT: [[TMP0:%.*]] = shl i8 [[X:%.*]], 5 ; CHECK-NEXT: call void @use8(i8 [[TMP0]]) ; CHECK-NEXT: [[TMP1:%.*]] = add i8 [[X]], -4 ; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i8 [[TMP1]], -8 ; CHECK-NEXT: ret i1 [[TMP2]] ; %tmp0 = shl i8 %x, 5 call void @use8(i8 %tmp0) %tmp1 = ashr exact i8 %tmp0, 5 %tmp2 = icmp ne i8 %tmp1, %x ret i1 %tmp2 } define i1 @n_oneuse1(i8 %x) { ; CHECK-LABEL: @n_oneuse1( ; CHECK-NEXT: [[TMP0:%.*]] = shl i8 [[X:%.*]], 5 ; CHECK-NEXT: [[TMP1:%.*]] = ashr exact i8 [[TMP0]], 5 ; CHECK-NEXT: call void @use8(i8 [[TMP1]]) ; CHECK-NEXT: [[TMP2:%.*]] = icmp ne i8 [[TMP1]], [[X]] ; CHECK-NEXT: ret i1 [[TMP2]] ; %tmp0 = shl i8 %x, 5 %tmp1 = ashr exact i8 %tmp0, 5 call void @use8(i8 %tmp1) %tmp2 = icmp ne i8 %tmp1, %x ret i1 %tmp2 } define i1 @n_oneuse2(i8 %x) { ; CHECK-LABEL: @n_oneuse2( ; CHECK-NEXT: [[TMP0:%.*]] = shl i8 [[X:%.*]], 5 ; CHECK-NEXT: call void @use8(i8 [[TMP0]]) ; CHECK-NEXT: [[TMP1:%.*]] = ashr exact i8 [[TMP0]], 5 ; CHECK-NEXT: call void @use8(i8 [[TMP1]]) ; CHECK-NEXT: [[TMP2:%.*]] = icmp ne i8 [[TMP1]], [[X]] ; CHECK-NEXT: ret i1 [[TMP2]] ; %tmp0 = shl i8 %x, 5 call void @use8(i8 %tmp0) %tmp1 = ashr exact i8 %tmp0, 5 call void @use8(i8 %tmp1) %tmp2 = icmp ne i8 %tmp1, %x ret i1 %tmp2 } ; ============================================================================ ; ; Negative tests ; ============================================================================ ; define i1 @n0(i8 %x) { ; CHECK-LABEL: @n0( ; CHECK-NEXT: [[TMP0:%.*]] = shl i8 [[X:%.*]], 5 ; CHECK-NEXT: [[TMP1:%.*]] = ashr exact i8 [[TMP0]], 3 ; CHECK-NEXT: [[TMP2:%.*]] = icmp ne i8 [[TMP1]], [[X]] ; CHECK-NEXT: ret i1 [[TMP2]] ; %tmp0 = shl i8 %x, 5 %tmp1 = ashr exact i8 %tmp0, 3 ; not 5 %tmp2 = icmp ne i8 %tmp1, %x ret i1 %tmp2 } define i1 @n1(i8 %x) { ; CHECK-LABEL: @n1( ; CHECK-NEXT: [[TMP1:%.*]] = icmp ugt i8 [[X:%.*]], 7 ; CHECK-NEXT: ret i1 [[TMP1]] ; %tmp0 = shl i8 %x, 5 %tmp1 = lshr exact i8 %tmp0, 5 ; not ashr %tmp2 = icmp ne i8 %tmp1, %x ret i1 %tmp2 } define i1 @n2(i8 %x, i8 %y) { ; CHECK-LABEL: @n2( ; CHECK-NEXT: [[TMP0:%.*]] = shl i8 [[X:%.*]], 5 ; CHECK-NEXT: [[TMP1:%.*]] = ashr exact i8 [[TMP0]], 5 ; CHECK-NEXT: [[TMP2:%.*]] = icmp ne i8 [[TMP1]], [[Y:%.*]] ; CHECK-NEXT: ret i1 [[TMP2]] ; %tmp0 = shl i8 %x, 5 %tmp1 = ashr exact i8 %tmp0, 5 %tmp2 = icmp ne i8 %tmp1, %y ; not %x ret i1 %tmp2 } define <2 x i1> @n3_vec_nonsplat(<2 x i8> %x) { ; CHECK-LABEL: @n3_vec_nonsplat( ; CHECK-NEXT: [[TMP0:%.*]] = shl <2 x i8> [[X:%.*]], <i8 5, i8 5> ; CHECK-NEXT: [[TMP1:%.*]] = ashr exact <2 x i8> [[TMP0]], <i8 5, i8 3> ; CHECK-NEXT: [[TMP2:%.*]] = icmp ne <2 x i8> [[TMP1]], [[X]] ; CHECK-NEXT: ret <2 x i1> [[TMP2]] ; %tmp0 = shl <2 x i8> %x, <i8 5, i8 5> %tmp1 = ashr exact <2 x i8> %tmp0, <i8 5, i8 3> ; 3 instead of 5 %tmp2 = icmp ne <2 x i8> %tmp1, %x ret <2 x i1> %tmp2 }