; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -passes=instcombine -S | FileCheck %s declare void @use.i8(i8) declare void @use.v2i4(<2 x i4>) declare void @use.i1(i1) declare void @llvm.assume(i1) ; Basic pattern define i8 @t0(i8 %x) { ; CHECK-LABEL: @t0( ; CHECK-NEXT: [[X_BIASED1:%.*]] = add i8 [[X:%.*]], 15 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = and i8 [[X_BIASED1]], -16 ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x, 15 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 0 %x.biased = add i8 %x, 16 %x.biased.highbits = and i8 %x.biased, -16 %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x, i8 %x.biased.highbits ret i8 %x.roundedup } ; Another alignment is fine define i8 @t1(i8 %x) { ; CHECK-LABEL: @t1( ; CHECK-NEXT: [[X_BIASED1:%.*]] = add i8 [[X:%.*]], 31 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = and i8 [[X_BIASED1]], -32 ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x, 31 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 0 %x.biased = add i8 %x, 32 %x.biased.highbits = and i8 %x.biased, -32 %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x, i8 %x.biased.highbits ret i8 %x.roundedup } ; Bias can be either the alignment or alignment-1 define i8 @t2(i8 %x) { ; CHECK-LABEL: @t2( ; CHECK-NEXT: [[X_BIASED1:%.*]] = add i8 [[X:%.*]], 15 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = and i8 [[X_BIASED1]], -16 ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x, 15 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 0 %x.biased = add i8 %x, 15 %x.biased.highbits = and i8 %x.biased, -16 %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x, i8 %x.biased.highbits ret i8 %x.roundedup } ; select is commutative define i8 @t3_commutative(i8 %x) { ; CHECK-LABEL: @t3_commutative( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and i8 [[X:%.*]], 15 ; CHECK-NEXT: [[X_LOWBITS_ARE_NOT_ZERO:%.*]] = icmp ne i8 [[X_LOWBITS]], 0 ; CHECK-NEXT: call void @use.i1(i1 [[X_LOWBITS_ARE_NOT_ZERO]]) ; CHECK-NEXT: [[X_BIASED1:%.*]] = add i8 [[X]], 15 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = and i8 [[X_BIASED1]], -16 ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x, 15 %x.lowbits.are.not.zero = icmp ne i8 %x.lowbits, 0 call void @use.i1(i1 %x.lowbits.are.not.zero) %x.biased = add i8 %x, 16 %x.biased.highbits = and i8 %x.biased, -16 %x.roundedup = select i1 %x.lowbits.are.not.zero, i8 %x.biased.highbits, i8 %x ret i8 %x.roundedup } ; Basic splat vector test define <2 x i8> @t4_splat(<2 x i8> %x) { ; CHECK-LABEL: @t4_splat( ; CHECK-NEXT: [[X_BIASED1:%.*]] = add <2 x i8> [[X:%.*]], <i8 15, i8 15> ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = and <2 x i8> [[X_BIASED1]], <i8 -16, i8 -16> ; CHECK-NEXT: ret <2 x i8> [[X_ROUNDEDUP]] ; %x.lowbits = and <2 x i8> %x, <i8 15, i8 15> %x.lowbits.are.zero = icmp eq <2 x i8> %x.lowbits, <i8 0, i8 0> %x.biased = add <2 x i8> %x, <i8 16, i8 16> %x.biased.highbits = and <2 x i8> %x.biased, <i8 -16, i8 -16> %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i8> %x, <2 x i8> %x.biased.highbits ret <2 x i8> %x.roundedup } ; Splat-with-undef define <2 x i8> @t5_splat_undef_0b0001(<2 x i8> %x) { ; CHECK-LABEL: @t5_splat_undef_0b0001( ; CHECK-NEXT: [[X_BIASED1:%.*]] = add <2 x i8> [[X:%.*]], <i8 15, i8 15> ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = and <2 x i8> [[X_BIASED1]], <i8 -16, i8 -16> ; CHECK-NEXT: ret <2 x i8> [[X_ROUNDEDUP]] ; %x.lowbits = and <2 x i8> %x, <i8 15, i8 15> %x.lowbits.are.zero = icmp eq <2 x i8> %x.lowbits, <i8 0, i8 0> %x.biased = add <2 x i8> %x, <i8 16, i8 16> %x.biased.highbits = and <2 x i8> %x.biased, <i8 -16, i8 undef> %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i8> %x, <2 x i8> %x.biased.highbits ret <2 x i8> %x.roundedup } define <2 x i8> @t5_splat_undef_0b0010(<2 x i8> %x) { ; CHECK-LABEL: @t5_splat_undef_0b0010( ; CHECK-NEXT: [[X_BIASED1:%.*]] = add <2 x i8> [[X:%.*]], <i8 15, i8 15> ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = and <2 x i8> [[X_BIASED1]], <i8 -16, i8 -16> ; CHECK-NEXT: ret <2 x i8> [[X_ROUNDEDUP]] ; %x.lowbits = and <2 x i8> %x, <i8 15, i8 15> %x.lowbits.are.zero = icmp eq <2 x i8> %x.lowbits, <i8 0, i8 0> %x.biased = add <2 x i8> %x, <i8 16, i8 undef> %x.biased.highbits = and <2 x i8> %x.biased, <i8 -16, i8 -16> %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i8> %x, <2 x i8> %x.biased.highbits ret <2 x i8> %x.roundedup } define <2 x i8> @t5_splat_undef_0b0100(<2 x i8> %x) { ; CHECK-LABEL: @t5_splat_undef_0b0100( ; CHECK-NEXT: [[X_BIASED1:%.*]] = add <2 x i8> [[X:%.*]], <i8 15, i8 15> ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = and <2 x i8> [[X_BIASED1]], <i8 -16, i8 -16> ; CHECK-NEXT: ret <2 x i8> [[X_ROUNDEDUP]] ; %x.lowbits = and <2 x i8> %x, <i8 15, i8 15> %x.lowbits.are.zero = icmp eq <2 x i8> %x.lowbits, <i8 0, i8 undef> %x.biased = add <2 x i8> %x, <i8 16, i8 16> %x.biased.highbits = and <2 x i8> %x.biased, <i8 -16, i8 -16> %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i8> %x, <2 x i8> %x.biased.highbits ret <2 x i8> %x.roundedup } define <2 x i8> @t5_splat_undef_0b1000(<2 x i8> %x) { ; CHECK-LABEL: @t5_splat_undef_0b1000( ; CHECK-NEXT: [[X_BIASED1:%.*]] = add <2 x i8> [[X:%.*]], <i8 15, i8 15> ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = and <2 x i8> [[X_BIASED1]], <i8 -16, i8 -16> ; CHECK-NEXT: ret <2 x i8> [[X_ROUNDEDUP]] ; %x.lowbits = and <2 x i8> %x, <i8 15, i8 undef> %x.lowbits.are.zero = icmp eq <2 x i8> %x.lowbits, <i8 0, i8 0> %x.biased = add <2 x i8> %x, <i8 16, i8 16> %x.biased.highbits = and <2 x i8> %x.biased, <i8 -16, i8 -16> %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i8> %x, <2 x i8> %x.biased.highbits ret <2 x i8> %x.roundedup } ; Basic non-splat vector test define <2 x i8> @t6_nonsplat(<2 x i8> %x) { ; CHECK-LABEL: @t6_nonsplat( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and <2 x i8> [[X:%.*]], <i8 15, i8 31> ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq <2 x i8> [[X_LOWBITS]], zeroinitializer ; CHECK-NEXT: [[X_BIASED:%.*]] = add <2 x i8> [[X]], <i8 16, i8 32> ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and <2 x i8> [[X_BIASED]], <i8 -16, i8 -32> ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select <2 x i1> [[X_LOWBITS_ARE_ZERO]], <2 x i8> [[X]], <2 x i8> [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret <2 x i8> [[X_ROUNDEDUP]] ; %x.lowbits = and <2 x i8> %x, <i8 15, i8 31> %x.lowbits.are.zero = icmp eq <2 x i8> %x.lowbits, <i8 0, i8 0> %x.biased = add <2 x i8> %x, <i8 16, i8 32> %x.biased.highbits = and <2 x i8> %x.biased, <i8 -16, i8 -32> %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i8> %x, <2 x i8> %x.biased.highbits ret <2 x i8> %x.roundedup } ; Even if the alignment (and masks) are splat, the bias could be non-splat define <2 x i8> @t7_nonsplat_bias(<2 x i8> %x) { ; CHECK-LABEL: @t7_nonsplat_bias( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and <2 x i8> [[X:%.*]], <i8 15, i8 15> ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq <2 x i8> [[X_LOWBITS]], zeroinitializer ; CHECK-NEXT: [[X_BIASED:%.*]] = add <2 x i8> [[X]], <i8 15, i8 16> ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and <2 x i8> [[X_BIASED]], <i8 -16, i8 -16> ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select <2 x i1> [[X_LOWBITS_ARE_ZERO]], <2 x i8> [[X]], <2 x i8> [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret <2 x i8> [[X_ROUNDEDUP]] ; %x.lowbits = and <2 x i8> %x, <i8 15, i8 15> %x.lowbits.are.zero = icmp eq <2 x i8> %x.lowbits, <i8 0, i8 0> %x.biased = add <2 x i8> %x, <i8 15, i8 16> %x.biased.highbits = and <2 x i8> %x.biased, <i8 -16, i8 -16> %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i8> %x, <2 x i8> %x.biased.highbits ret <2 x i8> %x.roundedup } ; Splat-in-disguise vector tests define <2 x i8> @t8_nonsplat_masked_by_undef_0b0001(<2 x i8> %x) { ; CHECK-LABEL: @t8_nonsplat_masked_by_undef_0b0001( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and <2 x i8> [[X:%.*]], <i8 15, i8 31> ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq <2 x i8> [[X_LOWBITS]], zeroinitializer ; CHECK-NEXT: [[X_BIASED:%.*]] = add <2 x i8> [[X]], <i8 16, i8 32> ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and <2 x i8> [[X_BIASED]], <i8 -16, i8 undef> ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select <2 x i1> [[X_LOWBITS_ARE_ZERO]], <2 x i8> [[X]], <2 x i8> [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret <2 x i8> [[X_ROUNDEDUP]] ; %x.lowbits = and <2 x i8> %x, <i8 15, i8 31> %x.lowbits.are.zero = icmp eq <2 x i8> %x.lowbits, <i8 0, i8 0> %x.biased = add <2 x i8> %x, <i8 16, i8 32> %x.biased.highbits = and <2 x i8> %x.biased, <i8 -16, i8 undef> %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i8> %x, <2 x i8> %x.biased.highbits ret <2 x i8> %x.roundedup } define <2 x i8> @t8_nonsplat_masked_by_undef_0b0010(<2 x i8> %x) { ; CHECK-LABEL: @t8_nonsplat_masked_by_undef_0b0010( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and <2 x i8> [[X:%.*]], <i8 15, i8 31> ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq <2 x i8> [[X_LOWBITS]], zeroinitializer ; CHECK-NEXT: [[X_BIASED:%.*]] = add <2 x i8> [[X]], <i8 16, i8 undef> ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and <2 x i8> [[X_BIASED]], <i8 -16, i8 -32> ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select <2 x i1> [[X_LOWBITS_ARE_ZERO]], <2 x i8> [[X]], <2 x i8> [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret <2 x i8> [[X_ROUNDEDUP]] ; %x.lowbits = and <2 x i8> %x, <i8 15, i8 31> %x.lowbits.are.zero = icmp eq <2 x i8> %x.lowbits, <i8 0, i8 0> %x.biased = add <2 x i8> %x, <i8 16, i8 undef> %x.biased.highbits = and <2 x i8> %x.biased, <i8 -16, i8 -32> %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i8> %x, <2 x i8> %x.biased.highbits ret <2 x i8> %x.roundedup } define <2 x i8> @t8_nonsplat_masked_by_undef_0b0100(<2 x i8> %x) { ; CHECK-LABEL: @t8_nonsplat_masked_by_undef_0b0100( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and <2 x i8> [[X:%.*]], <i8 15, i8 31> ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq <2 x i8> [[X_LOWBITS]], <i8 0, i8 undef> ; CHECK-NEXT: [[X_BIASED:%.*]] = add <2 x i8> [[X]], <i8 16, i8 32> ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and <2 x i8> [[X_BIASED]], <i8 -16, i8 -32> ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select <2 x i1> [[X_LOWBITS_ARE_ZERO]], <2 x i8> [[X]], <2 x i8> [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret <2 x i8> [[X_ROUNDEDUP]] ; %x.lowbits = and <2 x i8> %x, <i8 15, i8 31> %x.lowbits.are.zero = icmp eq <2 x i8> %x.lowbits, <i8 0, i8 undef> %x.biased = add <2 x i8> %x, <i8 16, i8 32> %x.biased.highbits = and <2 x i8> %x.biased, <i8 -16, i8 -32> %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i8> %x, <2 x i8> %x.biased.highbits ret <2 x i8> %x.roundedup } define <2 x i8> @t8_nonsplat_masked_by_undef_0b1000(<2 x i8> %x) { ; CHECK-LABEL: @t8_nonsplat_masked_by_undef_0b1000( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and <2 x i8> [[X:%.*]], <i8 15, i8 undef> ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq <2 x i8> [[X_LOWBITS]], zeroinitializer ; CHECK-NEXT: [[X_BIASED:%.*]] = add <2 x i8> [[X]], <i8 16, i8 32> ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and <2 x i8> [[X_BIASED]], <i8 -16, i8 -32> ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select <2 x i1> [[X_LOWBITS_ARE_ZERO]], <2 x i8> [[X]], <2 x i8> [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret <2 x i8> [[X_ROUNDEDUP]] ; %x.lowbits = and <2 x i8> %x, <i8 15, i8 undef> %x.lowbits.are.zero = icmp eq <2 x i8> %x.lowbits, <i8 0, i8 0> %x.biased = add <2 x i8> %x, <i8 16, i8 32> %x.biased.highbits = and <2 x i8> %x.biased, <i8 -16, i8 -32> %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i8> %x, <2 x i8> %x.biased.highbits ret <2 x i8> %x.roundedup } ; The X are different define i8 @n9_wrong_x0(i8 %x.0, i8 %x.1) { ; CHECK-LABEL: @n9_wrong_x0( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and i8 [[X_0:%.*]], 15 ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq i8 [[X_LOWBITS]], 0 ; CHECK-NEXT: [[X_BIASED:%.*]] = add i8 [[X_0]], 16 ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and i8 [[X_BIASED]], -16 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select i1 [[X_LOWBITS_ARE_ZERO]], i8 [[X_1:%.*]], i8 [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x.0, 15 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 0 %x.biased = add i8 %x.0, 16 %x.biased.highbits = and i8 %x.biased, -16 %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x.1, i8 %x.biased.highbits ret i8 %x.roundedup } define i8 @n9_wrong_x1(i8 %x.0, i8 %x.1) { ; CHECK-LABEL: @n9_wrong_x1( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and i8 [[X_0:%.*]], 15 ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq i8 [[X_LOWBITS]], 0 ; CHECK-NEXT: [[X_BIASED:%.*]] = add i8 [[X_1:%.*]], 16 ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and i8 [[X_BIASED]], -16 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select i1 [[X_LOWBITS_ARE_ZERO]], i8 [[X_0]], i8 [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x.0, 15 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 0 %x.biased = add i8 %x.1, 16 %x.biased.highbits = and i8 %x.biased, -16 %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x.0, i8 %x.biased.highbits ret i8 %x.roundedup } define i8 @n9_wrong_x2(i8 %x.0, i8 %x.1) { ; CHECK-LABEL: @n9_wrong_x2( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and i8 [[X_1:%.*]], 15 ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq i8 [[X_LOWBITS]], 0 ; CHECK-NEXT: [[X_BIASED:%.*]] = add i8 [[X_0:%.*]], 16 ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and i8 [[X_BIASED]], -16 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select i1 [[X_LOWBITS_ARE_ZERO]], i8 [[X_0]], i8 [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x.1, 15 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 0 %x.biased = add i8 %x.0, 16 %x.biased.highbits = and i8 %x.biased, -16 %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x.0, i8 %x.biased.highbits ret i8 %x.roundedup } ; Wrong low-bit mask define i8 @n10_wrong_low_bit_mask(i8 %x) { ; CHECK-LABEL: @n10_wrong_low_bit_mask( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and i8 [[X:%.*]], 31 ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq i8 [[X_LOWBITS]], 0 ; CHECK-NEXT: [[X_BIASED:%.*]] = add i8 [[X]], 16 ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and i8 [[X_BIASED]], -16 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select i1 [[X_LOWBITS_ARE_ZERO]], i8 [[X]], i8 [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x, 31 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 0 %x.biased = add i8 %x, 16 %x.biased.highbits = and i8 %x.biased, -16 %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x, i8 %x.biased.highbits ret i8 %x.roundedup } ; Wrong high-bit mask define i8 @n11_wrong_high_bit_mask(i8 %x) { ; CHECK-LABEL: @n11_wrong_high_bit_mask( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and i8 [[X:%.*]], 15 ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq i8 [[X_LOWBITS]], 0 ; CHECK-NEXT: [[X_BIASED:%.*]] = add i8 [[X]], 16 ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and i8 [[X_BIASED]], -32 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select i1 [[X_LOWBITS_ARE_ZERO]], i8 [[X]], i8 [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x, 15 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 0 %x.biased = add i8 %x, 16 %x.biased.highbits = and i8 %x.biased, -32 %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x, i8 %x.biased.highbits ret i8 %x.roundedup } ; Wrong bias define i8 @n12_wrong_bias(i8 %x) { ; CHECK-LABEL: @n12_wrong_bias( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and i8 [[X:%.*]], 15 ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq i8 [[X_LOWBITS]], 0 ; CHECK-NEXT: [[X_BIASED:%.*]] = add i8 [[X]], 32 ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and i8 [[X_BIASED]], -16 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select i1 [[X_LOWBITS_ARE_ZERO]], i8 [[X]], i8 [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x, 15 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 0 %x.biased = add i8 %x, 32 %x.biased.highbits = and i8 %x.biased, -16 %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x, i8 %x.biased.highbits ret i8 %x.roundedup } ; Wrong constants define i8 @n13_wrong_constants_alignment_is_not_power_of_two(i8 %x) { ; CHECK-LABEL: @n13_wrong_constants_alignment_is_not_power_of_two( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and i8 [[X:%.*]], 2 ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq i8 [[X_LOWBITS]], 0 ; CHECK-NEXT: [[X_BIASED:%.*]] = add i8 [[X]], 3 ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and i8 [[X_BIASED]], -3 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select i1 [[X_LOWBITS_ARE_ZERO]], i8 [[X]], i8 [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x, 2 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 0 %x.biased = add i8 %x, 3 %x.biased.highbits = and i8 %x.biased, -3 %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x, i8 %x.biased.highbits ret i8 %x.roundedup } ; Comparison is not with zero define i8 @n14_wrong_comparison_constant(i8 %x) { ; CHECK-LABEL: @n14_wrong_comparison_constant( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and i8 [[X:%.*]], 15 ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq i8 [[X_LOWBITS]], 1 ; CHECK-NEXT: [[X_BIASED:%.*]] = add i8 [[X]], 16 ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and i8 [[X_BIASED]], -16 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select i1 [[X_LOWBITS_ARE_ZERO]], i8 [[X]], i8 [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x, 15 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 1 %x.biased = add i8 %x, 16 %x.biased.highbits = and i8 %x.biased, -16 %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x, i8 %x.biased.highbits ret i8 %x.roundedup } ; Wrong comparison define i8 @n15_wrong_comparison_predicate_and_constant(i8 %x) { ; CHECK-LABEL: @n15_wrong_comparison_predicate_and_constant( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and i8 [[X:%.*]], 14 ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq i8 [[X_LOWBITS]], 0 ; CHECK-NEXT: [[X_BIASED:%.*]] = add i8 [[X]], 16 ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and i8 [[X_BIASED]], -16 ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select i1 [[X_LOWBITS_ARE_ZERO]], i8 [[X]], i8 [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x, 15 %x.lowbits.are.zero = icmp ult i8 %x.lowbits, 2 %x.biased = add i8 %x, 16 %x.biased.highbits = and i8 %x.biased, -16 %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x, i8 %x.biased.highbits ret i8 %x.roundedup } ; %x.biased.highbits must not have other uses define i8 @n16_oneuse(i8 %x) { ; CHECK-LABEL: @n16_oneuse( ; CHECK-NEXT: [[X_LOWBITS:%.*]] = and i8 [[X:%.*]], 15 ; CHECK-NEXT: [[X_LOWBITS_ARE_ZERO:%.*]] = icmp eq i8 [[X_LOWBITS]], 0 ; CHECK-NEXT: [[X_BIASED:%.*]] = add i8 [[X]], 16 ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and i8 [[X_BIASED]], -16 ; CHECK-NEXT: call void @use.i8(i8 [[X_BIASED_HIGHBITS]]) ; CHECK-NEXT: [[X_ROUNDEDUP:%.*]] = select i1 [[X_LOWBITS_ARE_ZERO]], i8 [[X]], i8 [[X_BIASED_HIGHBITS]] ; CHECK-NEXT: ret i8 [[X_ROUNDEDUP]] ; %x.lowbits = and i8 %x, 15 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 0 %x.biased = add i8 %x, 16 %x.biased.highbits = and i8 %x.biased, -16 call void @use.i8(i8 %x.biased.highbits) %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x, i8 %x.biased.highbits ret i8 %x.roundedup } ; But if bias is equal to low-bit mask, then we *could* just replace %x.roundedup with %x.biased.highbits define i8 @t17_oneuse(i8 %x) { ; CHECK-LABEL: @t17_oneuse( ; CHECK-NEXT: [[X_BIASED:%.*]] = add i8 [[X:%.*]], 15 ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and i8 [[X_BIASED]], -16 ; CHECK-NEXT: call void @use.i8(i8 [[X_BIASED_HIGHBITS]]) ; CHECK-NEXT: ret i8 [[X_BIASED_HIGHBITS]] ; %x.lowbits = and i8 %x, 15 %x.lowbits.are.zero = icmp eq i8 %x.lowbits, 0 %x.biased = add i8 %x, 15 %x.biased.highbits = and i8 %x.biased, -16 call void @use.i8(i8 %x.biased.highbits) %x.roundedup = select i1 %x.lowbits.are.zero, i8 %x, i8 %x.biased.highbits ret i8 %x.roundedup } ; Bias is equal to the alignment-1 (as opposed to alignment), ; so we can just replace %x.roundedup with %x.biased.highbits define <2 x i4> @t18_replacement_0b0001(<2 x i4> %x) { ; CHECK-LABEL: @t18_replacement_0b0001( ; CHECK-NEXT: [[X_BIASED:%.*]] = add <2 x i4> [[X:%.*]], <i4 3, i4 3> ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and <2 x i4> [[X_BIASED]], <i4 -4, i4 undef> ; CHECK-NEXT: call void @use.v2i4(<2 x i4> [[X_BIASED_HIGHBITS]]) ; CHECK-NEXT: ret <2 x i4> [[X_BIASED_HIGHBITS]] ; %x.lowbits = and <2 x i4> %x, <i4 3, i4 3> %x.lowbits.are.zero = icmp eq <2 x i4> %x.lowbits, <i4 0, i4 0> %x.biased = add <2 x i4> %x, <i4 3, i4 3> %x.biased.highbits = and <2 x i4> %x.biased, <i4 -4, i4 undef> call void @use.v2i4(<2 x i4> %x.biased.highbits) %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i4> %x, <2 x i4> %x.biased.highbits ret <2 x i4> %x.roundedup } define <2 x i4> @t18_replacement_0b0010(<2 x i4> %x) { ; CHECK-LABEL: @t18_replacement_0b0010( ; CHECK-NEXT: [[X_BIASED:%.*]] = add <2 x i4> [[X:%.*]], <i4 3, i4 undef> ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and <2 x i4> [[X_BIASED]], <i4 -4, i4 -4> ; CHECK-NEXT: call void @use.v2i4(<2 x i4> [[X_BIASED_HIGHBITS]]) ; CHECK-NEXT: ret <2 x i4> [[X_BIASED_HIGHBITS]] ; %x.lowbits = and <2 x i4> %x, <i4 3, i4 3> %x.lowbits.are.zero = icmp eq <2 x i4> %x.lowbits, <i4 0, i4 0> %x.biased = add <2 x i4> %x, <i4 3, i4 undef> %x.biased.highbits = and <2 x i4> %x.biased, <i4 -4, i4 -4> call void @use.v2i4(<2 x i4> %x.biased.highbits) %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i4> %x, <2 x i4> %x.biased.highbits ret <2 x i4> %x.roundedup } define <2 x i4> @t18_replacement_0b0100(<2 x i4> %x) { ; CHECK-LABEL: @t18_replacement_0b0100( ; CHECK-NEXT: [[X_BIASED:%.*]] = add <2 x i4> [[X:%.*]], <i4 3, i4 3> ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and <2 x i4> [[X_BIASED]], <i4 -4, i4 -4> ; CHECK-NEXT: call void @use.v2i4(<2 x i4> [[X_BIASED_HIGHBITS]]) ; CHECK-NEXT: ret <2 x i4> [[X_BIASED_HIGHBITS]] ; %x.lowbits = and <2 x i4> %x, <i4 3, i4 3> %x.lowbits.are.zero = icmp eq <2 x i4> %x.lowbits, <i4 0, i4 undef> %x.biased = add <2 x i4> %x, <i4 3, i4 3> %x.biased.highbits = and <2 x i4> %x.biased, <i4 -4, i4 -4> call void @use.v2i4(<2 x i4> %x.biased.highbits) %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i4> %x, <2 x i4> %x.biased.highbits ret <2 x i4> %x.roundedup } define <2 x i4> @t18_replacement_0b1000(<2 x i4> %x) { ; CHECK-LABEL: @t18_replacement_0b1000( ; CHECK-NEXT: [[X_BIASED:%.*]] = add <2 x i4> [[X:%.*]], <i4 3, i4 3> ; CHECK-NEXT: [[X_BIASED_HIGHBITS:%.*]] = and <2 x i4> [[X_BIASED]], <i4 -4, i4 -4> ; CHECK-NEXT: call void @use.v2i4(<2 x i4> [[X_BIASED_HIGHBITS]]) ; CHECK-NEXT: ret <2 x i4> [[X_BIASED_HIGHBITS]] ; %x.lowbits = and <2 x i4> %x, <i4 3, i4 undef> %x.lowbits.are.zero = icmp eq <2 x i4> %x.lowbits, <i4 0, i4 0> %x.biased = add <2 x i4> %x, <i4 3, i4 3> %x.biased.highbits = and <2 x i4> %x.biased, <i4 -4, i4 -4> call void @use.v2i4(<2 x i4> %x.biased.highbits) %x.roundedup = select <2 x i1> %x.lowbits.are.zero, <2 x i4> %x, <2 x i4> %x.biased.highbits ret <2 x i4> %x.roundedup }