1 ; RUN: opt -simplifycfg -S -o - < %s | FileCheck %s 2 3 declare void @helper(i32) 4 5 define void @test1(i1 %a, i1 %b) { 6 ; CHECK-LABEL: @test1( 7 entry: 8 br i1 %a, label %Y, label %X, !prof !0 9 ; CHECK: br i1 %or.cond, label %Z, label %Y, !prof !0 10 11 X: 12 %c = or i1 %b, false 13 br i1 %c, label %Z, label %Y, !prof !1 14 15 Y: 16 call void @helper(i32 0) 17 ret void 18 19 Z: 20 call void @helper(i32 1) 21 ret void 22 } 23 24 define void @test2(i1 %a, i1 %b) { 25 ; CHECK-LABEL: @test2( 26 entry: 27 br i1 %a, label %X, label %Y, !prof !1 28 ; CHECK: br i1 %or.cond, label %Z, label %Y, !prof !1 29 ; CHECK-NOT: !prof 30 31 X: 32 %c = or i1 %b, false 33 br i1 %c, label %Z, label %Y, !prof !2 34 35 Y: 36 call void @helper(i32 0) 37 ret void 38 39 Z: 40 call void @helper(i32 1) 41 ret void 42 } 43 44 define void @test3(i1 %a, i1 %b) { 45 ; CHECK-LABEL: @test3( 46 ; CHECK-NOT: !prof 47 entry: 48 br i1 %a, label %X, label %Y, !prof !1 49 50 X: 51 %c = or i1 %b, false 52 br i1 %c, label %Z, label %Y 53 54 Y: 55 call void @helper(i32 0) 56 ret void 57 58 Z: 59 call void @helper(i32 1) 60 ret void 61 } 62 63 define void @test4(i1 %a, i1 %b) { 64 ; CHECK-LABEL: @test4( 65 ; CHECK-NOT: !prof 66 entry: 67 br i1 %a, label %X, label %Y 68 69 X: 70 %c = or i1 %b, false 71 br i1 %c, label %Z, label %Y, !prof !1 72 73 Y: 74 call void @helper(i32 0) 75 ret void 76 77 Z: 78 call void @helper(i32 1) 79 ret void 80 } 81 82 ;; test5 - The case where it jumps to the default target will be removed. 83 define void @test5(i32 %M, i32 %N) nounwind uwtable { 84 entry: 85 switch i32 %N, label %sw2 [ 86 i32 1, label %sw2 87 i32 2, label %sw.bb 88 i32 3, label %sw.bb1 89 ], !prof !3 90 ; CHECK-LABEL: @test5( 91 ; CHECK: switch i32 %N, label %sw2 [ 92 ; CHECK: i32 3, label %sw.bb1 93 ; CHECK: i32 2, label %sw.bb 94 ; CHECK: ], !prof !2 95 96 sw.bb: 97 call void @helper(i32 0) 98 br label %sw.epilog 99 100 sw.bb1: 101 call void @helper(i32 1) 102 br label %sw.epilog 103 104 sw2: 105 call void @helper(i32 2) 106 br label %sw.epilog 107 108 sw.epilog: 109 ret void 110 } 111 112 ;; test6 - Some cases of the second switch are pruned during optimization. 113 ;; Then the second switch will be converted to a branch, finally, the first 114 ;; switch and the branch will be merged into a single switch. 115 define void @test6(i32 %M, i32 %N) nounwind uwtable { 116 entry: 117 switch i32 %N, label %sw2 [ 118 i32 1, label %sw2 119 i32 2, label %sw.bb 120 i32 3, label %sw.bb1 121 ], !prof !4 122 ; CHECK-LABEL: @test6( 123 ; CHECK: switch i32 %N, label %sw.epilog 124 ; CHECK: i32 3, label %sw.bb1 125 ; CHECK: i32 2, label %sw.bb 126 ; CHECK: i32 4, label %sw.bb5 127 ; CHECK: ], !prof !3 128 129 sw.bb: 130 call void @helper(i32 0) 131 br label %sw.epilog 132 133 sw.bb1: 134 call void @helper(i32 1) 135 br label %sw.epilog 136 137 sw2: 138 ;; Here "case 2" is invalidated since the default case of the first switch 139 ;; does not include "case 2". 140 switch i32 %N, label %sw.epilog [ 141 i32 2, label %sw.bb4 142 i32 4, label %sw.bb5 143 ], !prof !5 144 145 sw.bb4: 146 call void @helper(i32 2) 147 br label %sw.epilog 148 149 sw.bb5: 150 call void @helper(i32 3) 151 br label %sw.epilog 152 153 sw.epilog: 154 ret void 155 } 156 157 ;; This test is based on test1 but swapped the targets of the second branch. 158 define void @test1_swap(i1 %a, i1 %b) { 159 ; CHECK-LABEL: @test1_swap( 160 entry: 161 br i1 %a, label %Y, label %X, !prof !0 162 ; CHECK: br i1 %or.cond, label %Y, label %Z, !prof !4 163 164 X: 165 %c = or i1 %b, false 166 br i1 %c, label %Y, label %Z, !prof !1 167 168 Y: 169 call void @helper(i32 0) 170 ret void 171 172 Z: 173 call void @helper(i32 1) 174 ret void 175 } 176 177 define void @test7(i1 %a, i1 %b) { 178 ; CHECK-LABEL: @test7( 179 entry: 180 %c = or i1 %b, false 181 br i1 %a, label %Y, label %X, !prof !0 182 ; CHECK: br i1 %brmerge, label %Y, label %Z, !prof !5 183 184 X: 185 br i1 %c, label %Y, label %Z, !prof !6 186 187 Y: 188 call void @helper(i32 0) 189 ret void 190 191 Z: 192 call void @helper(i32 1) 193 ret void 194 } 195 196 ; Test basic folding to a conditional branch. 197 define void @test8(i64 %x, i64 %y) nounwind { 198 ; CHECK-LABEL: @test8( 199 entry: 200 %lt = icmp slt i64 %x, %y 201 ; CHECK: br i1 %lt, label %a, label %b, !prof !6 202 %qux = select i1 %lt, i32 0, i32 2 203 switch i32 %qux, label %bees [ 204 i32 0, label %a 205 i32 1, label %b 206 i32 2, label %b 207 ], !prof !7 208 a: 209 call void @helper(i32 0) nounwind 210 ret void 211 b: 212 call void @helper(i32 1) nounwind 213 ret void 214 bees: 215 call void @helper(i32 2) nounwind 216 ret void 217 } 218 219 ; Test edge splitting when the default target has icmp and unconditinal 220 ; branch 221 define i1 @test9(i32 %x, i32 %y) nounwind { 222 ; CHECK-LABEL: @test9( 223 entry: 224 switch i32 %x, label %bees [ 225 i32 0, label %a 226 i32 1, label %end 227 i32 2, label %end 228 ], !prof !7 229 ; CHECK: switch i32 %x, label %bees [ 230 ; CHECK: i32 0, label %a 231 ; CHECK: i32 1, label %end 232 ; CHECK: i32 2, label %end 233 ; CHECK: i32 92, label %end 234 ; CHECK: ], !prof !7 235 236 a: 237 call void @helper(i32 0) nounwind 238 %reta = icmp slt i32 %x, %y 239 ret i1 %reta 240 241 bees: 242 %tmp = icmp eq i32 %x, 92 243 br label %end 244 245 end: 246 ; CHECK: end: 247 ; CHECK: %ret = phi i1 [ true, %entry ], [ false, %bees ], [ true, %entry ], [ true, %entry ] 248 %ret = phi i1 [ true, %entry ], [%tmp, %bees], [true, %entry] 249 call void @helper(i32 2) nounwind 250 ret i1 %ret 251 } 252 253 define void @test10(i32 %x) nounwind readnone ssp noredzone { 254 entry: 255 switch i32 %x, label %lor.rhs [ 256 i32 2, label %lor.end 257 i32 1, label %lor.end 258 i32 3, label %lor.end 259 ], !prof !7 260 261 lor.rhs: 262 call void @helper(i32 1) nounwind 263 ret void 264 265 lor.end: 266 call void @helper(i32 0) nounwind 267 ret void 268 269 ; CHECK-LABEL: @test10( 270 ; CHECK: %x.off = add i32 %x, -1 271 ; CHECK: %switch = icmp ult i32 %x.off, 3 272 ; CHECK: br i1 %switch, label %lor.end, label %lor.rhs, !prof !8 273 } 274 275 ; Remove dead cases from the switch. 276 define void @test11(i32 %x) nounwind { 277 %i = shl i32 %x, 1 278 switch i32 %i, label %a [ 279 i32 21, label %b 280 i32 24, label %c 281 ], !prof !8 282 ; CHECK-LABEL: @test11( 283 ; CHECK: %cond = icmp eq i32 %i, 24 284 ; CHECK: br i1 %cond, label %c, label %a, !prof !9 285 286 a: 287 call void @helper(i32 0) nounwind 288 ret void 289 b: 290 call void @helper(i32 1) nounwind 291 ret void 292 c: 293 call void @helper(i32 2) nounwind 294 ret void 295 } 296 297 ;; test12 - Don't crash if the whole switch is removed 298 define void @test12(i32 %M, i32 %N) nounwind uwtable { 299 entry: 300 switch i32 %N, label %sw.bb [ 301 i32 1, label %sw.bb 302 ], !prof !9 303 ; CHECK-LABEL: @test12( 304 ; CHECK-NEXT: entry: 305 ; CHECK-NEXT: call void @helper 306 ; CHECK-NEXT: ret void 307 308 sw.bb: 309 call void @helper(i32 0) 310 br label %sw.epilog 311 312 sw.epilog: 313 ret void 314 } 315 316 ;; If every case is dead, make sure they are all removed. This used to 317 ;; crash trying to merge the metadata. 318 define void @test13(i32 %x) nounwind { 319 entry: 320 %i = shl i32 %x, 1 321 switch i32 %i, label %a [ 322 i32 21, label %b 323 i32 25, label %c 324 ], !prof !8 325 ; CHECK-LABEL: @test13( 326 ; CHECK-NEXT: entry: 327 ; CHECK-NEXT: call void @helper 328 ; CHECK-NEXT: ret void 329 330 a: 331 call void @helper(i32 0) nounwind 332 ret void 333 b: 334 call void @helper(i32 1) nounwind 335 ret void 336 c: 337 call void @helper(i32 2) nounwind 338 ret void 339 } 340 341 ;; When folding branches to common destination, the updated branch weights 342 ;; can exceed uint32 by more than factor of 2. We should keep halving the 343 ;; weights until they can fit into uint32. 344 @max_regno = common global i32 0, align 4 345 define void @test14(i32* %old, i32 %final) { 346 ; CHECK-LABEL: @test14 347 ; CHECK: br i1 %or.cond, label %for.exit, label %for.inc, !prof !10 348 for.cond: 349 br label %for.cond2 350 for.cond2: 351 %i.1 = phi i32 [ %inc19, %for.inc ], [ 0, %for.cond ] 352 %bit.0 = phi i32 [ %shl, %for.inc ], [ 1, %for.cond ] 353 %tobool = icmp eq i32 %bit.0, 0 354 br i1 %tobool, label %for.exit, label %for.body3, !prof !10 355 for.body3: 356 %v3 = load i32, i32* @max_regno, align 4 357 %cmp4 = icmp eq i32 %i.1, %v3 358 br i1 %cmp4, label %for.exit, label %for.inc, !prof !11 359 for.inc: 360 %shl = shl i32 %bit.0, 1 361 %inc19 = add nsw i32 %i.1, 1 362 br label %for.cond2 363 for.exit: 364 ret void 365 } 366 367 !0 = !{!"branch_weights", i32 3, i32 5} 368 !1 = !{!"branch_weights", i32 1, i32 1} 369 !2 = !{!"branch_weights", i32 1, i32 2} 370 !3 = !{!"branch_weights", i32 4, i32 3, i32 2, i32 1} 371 !4 = !{!"branch_weights", i32 4, i32 3, i32 2, i32 1} 372 !5 = !{!"branch_weights", i32 7, i32 6, i32 5} 373 !6 = !{!"branch_weights", i32 1, i32 3} 374 !7 = !{!"branch_weights", i32 33, i32 9, i32 8, i32 7} 375 !8 = !{!"branch_weights", i32 33, i32 9, i32 8} 376 !9 = !{!"branch_weights", i32 7, i32 6} 377 !10 = !{!"branch_weights", i32 672646, i32 21604207} 378 !11 = !{!"branch_weights", i32 6960, i32 21597248} 379 380 ; CHECK: !0 = !{!"branch_weights", i32 5, i32 11} 381 ; CHECK: !1 = !{!"branch_weights", i32 1, i32 5} 382 ; CHECK: !2 = !{!"branch_weights", i32 7, i32 1, i32 2} 383 ; CHECK: !3 = !{!"branch_weights", i32 49, i32 12, i32 24, i32 35} 384 ; CHECK: !4 = !{!"branch_weights", i32 11, i32 5} 385 ; CHECK: !5 = !{!"branch_weights", i32 17, i32 15} 386 ; CHECK: !6 = !{!"branch_weights", i32 9, i32 7} 387 ; CHECK: !7 = !{!"branch_weights", i32 17, i32 9, i32 8, i32 7, i32 17} 388 ; CHECK: !8 = !{!"branch_weights", i32 24, i32 33} 389 ; CHECK: !9 = !{!"branch_weights", i32 8, i32 33} 390 ;; The false weight prints out as a negative integer here, but inside llvm, we 391 ;; treat the weight as an unsigned integer. 392 ; CHECK: !10 = !{!"branch_weights", i32 112017436, i32 -735157296} 393
