1 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py 2 ; RUN: opt < %s -instsimplify -S | FileCheck %s 3 4 define i32 @zero_dividend(i32 %A) { 5 ; CHECK-LABEL: @zero_dividend( 6 ; CHECK-NEXT: ret i32 0 7 ; 8 %B = sdiv i32 0, %A 9 ret i32 %B 10 } 11 12 define <2 x i32> @zero_dividend_vector(<2 x i32> %A) { 13 ; CHECK-LABEL: @zero_dividend_vector( 14 ; CHECK-NEXT: ret <2 x i32> zeroinitializer 15 ; 16 %B = udiv <2 x i32> zeroinitializer, %A 17 ret <2 x i32> %B 18 } 19 20 define <2 x i32> @zero_dividend_vector_undef_elt(<2 x i32> %A) { 21 ; CHECK-LABEL: @zero_dividend_vector_undef_elt( 22 ; CHECK-NEXT: ret <2 x i32> zeroinitializer 23 ; 24 %B = sdiv <2 x i32> <i32 0, i32 undef>, %A 25 ret <2 x i32> %B 26 } 27 28 ; Division-by-zero is undef. UB in any vector lane means the whole op is undef. 29 30 define <2 x i8> @sdiv_zero_elt_vec_constfold(<2 x i8> %x) { 31 ; CHECK-LABEL: @sdiv_zero_elt_vec_constfold( 32 ; CHECK-NEXT: ret <2 x i8> undef 33 ; 34 %div = sdiv <2 x i8> <i8 1, i8 2>, <i8 0, i8 -42> 35 ret <2 x i8> %div 36 } 37 38 define <2 x i8> @udiv_zero_elt_vec_constfold(<2 x i8> %x) { 39 ; CHECK-LABEL: @udiv_zero_elt_vec_constfold( 40 ; CHECK-NEXT: ret <2 x i8> undef 41 ; 42 %div = udiv <2 x i8> <i8 1, i8 2>, <i8 42, i8 0> 43 ret <2 x i8> %div 44 } 45 46 define <2 x i8> @sdiv_zero_elt_vec(<2 x i8> %x) { 47 ; CHECK-LABEL: @sdiv_zero_elt_vec( 48 ; CHECK-NEXT: ret <2 x i8> undef 49 ; 50 %div = sdiv <2 x i8> %x, <i8 -42, i8 0> 51 ret <2 x i8> %div 52 } 53 54 define <2 x i8> @udiv_zero_elt_vec(<2 x i8> %x) { 55 ; CHECK-LABEL: @udiv_zero_elt_vec( 56 ; CHECK-NEXT: ret <2 x i8> undef 57 ; 58 %div = udiv <2 x i8> %x, <i8 0, i8 42> 59 ret <2 x i8> %div 60 } 61 62 define <2 x i8> @sdiv_undef_elt_vec(<2 x i8> %x) { 63 ; CHECK-LABEL: @sdiv_undef_elt_vec( 64 ; CHECK-NEXT: ret <2 x i8> undef 65 ; 66 %div = sdiv <2 x i8> %x, <i8 -42, i8 undef> 67 ret <2 x i8> %div 68 } 69 70 define <2 x i8> @udiv_undef_elt_vec(<2 x i8> %x) { 71 ; CHECK-LABEL: @udiv_undef_elt_vec( 72 ; CHECK-NEXT: ret <2 x i8> undef 73 ; 74 %div = udiv <2 x i8> %x, <i8 undef, i8 42> 75 ret <2 x i8> %div 76 } 77 78 ; Division-by-zero is undef. UB in any vector lane means the whole op is undef. 79 ; Thus, we can simplify this: if any element of 'y' is 0, we can do anything. 80 ; Therefore, assume that all elements of 'y' must be 1. 81 82 define <2 x i1> @sdiv_bool_vec(<2 x i1> %x, <2 x i1> %y) { 83 ; CHECK-LABEL: @sdiv_bool_vec( 84 ; CHECK-NEXT: ret <2 x i1> [[X:%.*]] 85 ; 86 %div = sdiv <2 x i1> %x, %y 87 ret <2 x i1> %div 88 } 89 90 define <2 x i1> @udiv_bool_vec(<2 x i1> %x, <2 x i1> %y) { 91 ; CHECK-LABEL: @udiv_bool_vec( 92 ; CHECK-NEXT: ret <2 x i1> [[X:%.*]] 93 ; 94 %div = udiv <2 x i1> %x, %y 95 ret <2 x i1> %div 96 } 97 98 define i32 @zext_bool_udiv_divisor(i1 %x, i32 %y) { 99 ; CHECK-LABEL: @zext_bool_udiv_divisor( 100 ; CHECK-NEXT: ret i32 [[Y:%.*]] 101 ; 102 %ext = zext i1 %x to i32 103 %r = udiv i32 %y, %ext 104 ret i32 %r 105 } 106 107 define <2 x i32> @zext_bool_sdiv_divisor_vec(<2 x i1> %x, <2 x i32> %y) { 108 ; CHECK-LABEL: @zext_bool_sdiv_divisor_vec( 109 ; CHECK-NEXT: ret <2 x i32> [[Y:%.*]] 110 ; 111 %ext = zext <2 x i1> %x to <2 x i32> 112 %r = sdiv <2 x i32> %y, %ext 113 ret <2 x i32> %r 114 } 115 116 define i32 @udiv_dividend_known_smaller_than_constant_divisor(i32 %x) { 117 ; CHECK-LABEL: @udiv_dividend_known_smaller_than_constant_divisor( 118 ; CHECK-NEXT: ret i32 0 119 ; 120 %and = and i32 %x, 250 121 %div = udiv i32 %and, 251 122 ret i32 %div 123 } 124 125 define i32 @not_udiv_dividend_known_smaller_than_constant_divisor(i32 %x) { 126 ; CHECK-LABEL: @not_udiv_dividend_known_smaller_than_constant_divisor( 127 ; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 251 128 ; CHECK-NEXT: [[DIV:%.*]] = udiv i32 [[AND]], 251 129 ; CHECK-NEXT: ret i32 [[DIV]] 130 ; 131 %and = and i32 %x, 251 132 %div = udiv i32 %and, 251 133 ret i32 %div 134 } 135 136 define i32 @udiv_constant_dividend_known_smaller_than_divisor(i32 %x) { 137 ; CHECK-LABEL: @udiv_constant_dividend_known_smaller_than_divisor( 138 ; CHECK-NEXT: ret i32 0 139 ; 140 %or = or i32 %x, 251 141 %div = udiv i32 250, %or 142 ret i32 %div 143 } 144 145 define i32 @not_udiv_constant_dividend_known_smaller_than_divisor(i32 %x) { 146 ; CHECK-LABEL: @not_udiv_constant_dividend_known_smaller_than_divisor( 147 ; CHECK-NEXT: [[OR:%.*]] = or i32 [[X:%.*]], 251 148 ; CHECK-NEXT: [[DIV:%.*]] = udiv i32 251, [[OR]] 149 ; CHECK-NEXT: ret i32 [[DIV]] 150 ; 151 %or = or i32 %x, 251 152 %div = udiv i32 251, %or 153 ret i32 %div 154 } 155 156 ; This would require computing known bits on both x and y. Is it worth doing? 157 158 define i32 @udiv_dividend_known_smaller_than_divisor(i32 %x, i32 %y) { 159 ; CHECK-LABEL: @udiv_dividend_known_smaller_than_divisor( 160 ; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 250 161 ; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 251 162 ; CHECK-NEXT: [[DIV:%.*]] = udiv i32 [[AND]], [[OR]] 163 ; CHECK-NEXT: ret i32 [[DIV]] 164 ; 165 %and = and i32 %x, 250 166 %or = or i32 %y, 251 167 %div = udiv i32 %and, %or 168 ret i32 %div 169 } 170 171 define i32 @not_udiv_dividend_known_smaller_than_divisor(i32 %x, i32 %y) { 172 ; CHECK-LABEL: @not_udiv_dividend_known_smaller_than_divisor( 173 ; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 251 174 ; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 251 175 ; CHECK-NEXT: [[DIV:%.*]] = udiv i32 [[AND]], [[OR]] 176 ; CHECK-NEXT: ret i32 [[DIV]] 177 ; 178 %and = and i32 %x, 251 179 %or = or i32 %y, 251 180 %div = udiv i32 %and, %or 181 ret i32 %div 182 } 183 184 declare i32 @external() 185 186 define i32 @div1() { 187 ; CHECK-LABEL: @div1( 188 ; CHECK-NEXT: [[CALL:%.*]] = call i32 @external(), !range !0 189 ; CHECK-NEXT: ret i32 0 190 ; 191 %call = call i32 @external(), !range !0 192 %urem = udiv i32 %call, 3 193 ret i32 %urem 194 } 195 196 !0 = !{i32 0, i32 3} 197
