1; RUN: opt < %s -instsimplify -S | FileCheck %s 2target datalayout = "p:32:32" 3 4define i1 @ptrtoint() { 5; CHECK-LABEL: @ptrtoint( 6 %a = alloca i8 7 %tmp = ptrtoint i8* %a to i32 8 %r = icmp eq i32 %tmp, 0 9 ret i1 %r 10; CHECK: ret i1 false 11} 12 13define i1 @bitcast() { 14; CHECK-LABEL: @bitcast( 15 %a = alloca i32 16 %b = alloca i64 17 %x = bitcast i32* %a to i8* 18 %y = bitcast i64* %b to i8* 19 %cmp = icmp eq i8* %x, %y 20 ret i1 %cmp 21; CHECK-NEXT: ret i1 false 22} 23 24define i1 @gep() { 25; CHECK-LABEL: @gep( 26 %a = alloca [3 x i8], align 8 27 %x = getelementptr inbounds [3 x i8]* %a, i32 0, i32 0 28 %cmp = icmp eq i8* %x, null 29 ret i1 %cmp 30; CHECK-NEXT: ret i1 false 31} 32 33define i1 @gep2() { 34; CHECK-LABEL: @gep2( 35 %a = alloca [3 x i8], align 8 36 %x = getelementptr inbounds [3 x i8]* %a, i32 0, i32 0 37 %y = getelementptr inbounds [3 x i8]* %a, i32 0, i32 0 38 %cmp = icmp eq i8* %x, %y 39 ret i1 %cmp 40; CHECK-NEXT: ret i1 true 41} 42 43; PR11238 44%gept = type { i32, i32 } 45@gepy = global %gept zeroinitializer, align 8 46@gepz = extern_weak global %gept 47 48define i1 @gep3() { 49; CHECK-LABEL: @gep3( 50 %x = alloca %gept, align 8 51 %a = getelementptr %gept* %x, i64 0, i32 0 52 %b = getelementptr %gept* %x, i64 0, i32 1 53 %equal = icmp eq i32* %a, %b 54 ret i1 %equal 55; CHECK-NEXT: ret i1 false 56} 57 58define i1 @gep4() { 59; CHECK-LABEL: @gep4( 60 %x = alloca %gept, align 8 61 %a = getelementptr %gept* @gepy, i64 0, i32 0 62 %b = getelementptr %gept* @gepy, i64 0, i32 1 63 %equal = icmp eq i32* %a, %b 64 ret i1 %equal 65; CHECK-NEXT: ret i1 false 66} 67 68define i1 @gep5() { 69; CHECK-LABEL: @gep5( 70 %x = alloca %gept, align 8 71 %a = getelementptr inbounds %gept* %x, i64 0, i32 1 72 %b = getelementptr %gept* @gepy, i64 0, i32 0 73 %equal = icmp eq i32* %a, %b 74 ret i1 %equal 75; CHECK-NEXT: ret i1 false 76} 77 78define i1 @gep6(%gept* %x) { 79; Same as @gep3 but potentially null. 80; CHECK-LABEL: @gep6( 81 %a = getelementptr %gept* %x, i64 0, i32 0 82 %b = getelementptr %gept* %x, i64 0, i32 1 83 %equal = icmp eq i32* %a, %b 84 ret i1 %equal 85; CHECK-NEXT: ret i1 false 86} 87 88define i1 @gep7(%gept* %x) { 89; CHECK-LABEL: @gep7( 90 %a = getelementptr %gept* %x, i64 0, i32 0 91 %b = getelementptr %gept* @gepz, i64 0, i32 0 92 %equal = icmp eq i32* %a, %b 93 ret i1 %equal 94; CHECK: ret i1 %equal 95} 96 97define i1 @gep8(%gept* %x) { 98; CHECK-LABEL: @gep8( 99 %a = getelementptr %gept* %x, i32 1 100 %b = getelementptr %gept* %x, i32 -1 101 %equal = icmp ugt %gept* %a, %b 102 ret i1 %equal 103; CHECK: ret i1 %equal 104} 105 106define i1 @gep9(i8* %ptr) { 107; CHECK-LABEL: @gep9( 108; CHECK-NOT: ret 109; CHECK: ret i1 true 110 111entry: 112 %first1 = getelementptr inbounds i8* %ptr, i32 0 113 %first2 = getelementptr inbounds i8* %first1, i32 1 114 %first3 = getelementptr inbounds i8* %first2, i32 2 115 %first4 = getelementptr inbounds i8* %first3, i32 4 116 %last1 = getelementptr inbounds i8* %first2, i32 48 117 %last2 = getelementptr inbounds i8* %last1, i32 8 118 %last3 = getelementptr inbounds i8* %last2, i32 -4 119 %last4 = getelementptr inbounds i8* %last3, i32 -4 120 %first.int = ptrtoint i8* %first4 to i32 121 %last.int = ptrtoint i8* %last4 to i32 122 %cmp = icmp ne i32 %last.int, %first.int 123 ret i1 %cmp 124} 125 126define i1 @gep10(i8* %ptr) { 127; CHECK-LABEL: @gep10( 128; CHECK-NOT: ret 129; CHECK: ret i1 true 130 131entry: 132 %first1 = getelementptr inbounds i8* %ptr, i32 -2 133 %first2 = getelementptr inbounds i8* %first1, i32 44 134 %last1 = getelementptr inbounds i8* %ptr, i32 48 135 %last2 = getelementptr inbounds i8* %last1, i32 -6 136 %first.int = ptrtoint i8* %first2 to i32 137 %last.int = ptrtoint i8* %last2 to i32 138 %cmp = icmp eq i32 %last.int, %first.int 139 ret i1 %cmp 140} 141 142define i1 @gep11(i8* %ptr) { 143; CHECK-LABEL: @gep11( 144; CHECK-NOT: ret 145; CHECK: ret i1 true 146 147entry: 148 %first1 = getelementptr inbounds i8* %ptr, i32 -2 149 %last1 = getelementptr inbounds i8* %ptr, i32 48 150 %last2 = getelementptr inbounds i8* %last1, i32 -6 151 %cmp = icmp ult i8* %first1, %last2 152 ret i1 %cmp 153} 154 155define i1 @gep12(i8* %ptr) { 156; CHECK-LABEL: @gep12( 157; CHECK-NOT: ret 158; CHECK: ret i1 %cmp 159 160entry: 161 %first1 = getelementptr inbounds i8* %ptr, i32 -2 162 %last1 = getelementptr inbounds i8* %ptr, i32 48 163 %last2 = getelementptr inbounds i8* %last1, i32 -6 164 %cmp = icmp slt i8* %first1, %last2 165 ret i1 %cmp 166} 167 168define i1 @gep13(i8* %ptr) { 169; CHECK-LABEL: @gep13( 170; We can prove this GEP is non-null because it is inbounds. 171 %x = getelementptr inbounds i8* %ptr, i32 1 172 %cmp = icmp eq i8* %x, null 173 ret i1 %cmp 174; CHECK-NEXT: ret i1 false 175} 176 177define i1 @gep14({ {}, i8 }* %ptr) { 178; CHECK-LABEL: @gep14( 179; We can't simplify this because the offset of one in the GEP actually doesn't 180; move the pointer. 181 %x = getelementptr inbounds { {}, i8 }* %ptr, i32 0, i32 1 182 %cmp = icmp eq i8* %x, null 183 ret i1 %cmp 184; CHECK-NOT: ret i1 false 185} 186 187define i1 @gep15({ {}, [4 x {i8, i8}]}* %ptr, i32 %y) { 188; CHECK-LABEL: @gep15( 189; We can prove this GEP is non-null even though there is a user value, as we 190; would necessarily violate inbounds on one side or the other. 191 %x = getelementptr inbounds { {}, [4 x {i8, i8}]}* %ptr, i32 0, i32 1, i32 %y, i32 1 192 %cmp = icmp eq i8* %x, null 193 ret i1 %cmp 194; CHECK-NEXT: ret i1 false 195} 196 197define i1 @gep16(i8* %ptr, i32 %a) { 198; CHECK-LABEL: @gep16( 199; We can prove this GEP is non-null because it is inbounds and because we know 200; %b is non-zero even though we don't know its value. 201 %b = or i32 %a, 1 202 %x = getelementptr inbounds i8* %ptr, i32 %b 203 %cmp = icmp eq i8* %x, null 204 ret i1 %cmp 205; CHECK-NEXT: ret i1 false 206} 207 208define i1 @zext(i32 %x) { 209; CHECK-LABEL: @zext( 210 %e1 = zext i32 %x to i64 211 %e2 = zext i32 %x to i64 212 %r = icmp eq i64 %e1, %e2 213 ret i1 %r 214; CHECK: ret i1 true 215} 216 217define i1 @zext2(i1 %x) { 218; CHECK-LABEL: @zext2( 219 %e = zext i1 %x to i32 220 %c = icmp ne i32 %e, 0 221 ret i1 %c 222; CHECK: ret i1 %x 223} 224 225define i1 @zext3() { 226; CHECK-LABEL: @zext3( 227 %e = zext i1 1 to i32 228 %c = icmp ne i32 %e, 0 229 ret i1 %c 230; CHECK: ret i1 true 231} 232 233define i1 @sext(i32 %x) { 234; CHECK-LABEL: @sext( 235 %e1 = sext i32 %x to i64 236 %e2 = sext i32 %x to i64 237 %r = icmp eq i64 %e1, %e2 238 ret i1 %r 239; CHECK: ret i1 true 240} 241 242define i1 @sext2(i1 %x) { 243; CHECK-LABEL: @sext2( 244 %e = sext i1 %x to i32 245 %c = icmp ne i32 %e, 0 246 ret i1 %c 247; CHECK: ret i1 %x 248} 249 250define i1 @sext3() { 251; CHECK-LABEL: @sext3( 252 %e = sext i1 1 to i32 253 %c = icmp ne i32 %e, 0 254 ret i1 %c 255; CHECK: ret i1 true 256} 257 258define i1 @add(i32 %x, i32 %y) { 259; CHECK-LABEL: @add( 260 %l = lshr i32 %x, 1 261 %q = lshr i32 %y, 1 262 %r = or i32 %q, 1 263 %s = add i32 %l, %r 264 %c = icmp eq i32 %s, 0 265 ret i1 %c 266; CHECK: ret i1 false 267} 268 269define i1 @add2(i8 %x, i8 %y) { 270; CHECK-LABEL: @add2( 271 %l = or i8 %x, 128 272 %r = or i8 %y, 129 273 %s = add i8 %l, %r 274 %c = icmp eq i8 %s, 0 275 ret i1 %c 276; CHECK: ret i1 false 277} 278 279define i1 @add3(i8 %x, i8 %y) { 280; CHECK-LABEL: @add3( 281 %l = zext i8 %x to i32 282 %r = zext i8 %y to i32 283 %s = add i32 %l, %r 284 %c = icmp eq i32 %s, 0 285 ret i1 %c 286; CHECK: ret i1 %c 287} 288 289define i1 @add4(i32 %x, i32 %y) { 290; CHECK-LABEL: @add4( 291 %z = add nsw i32 %y, 1 292 %s1 = add nsw i32 %x, %y 293 %s2 = add nsw i32 %x, %z 294 %c = icmp slt i32 %s1, %s2 295 ret i1 %c 296; CHECK: ret i1 true 297} 298 299define i1 @add5(i32 %x, i32 %y) { 300; CHECK-LABEL: @add5( 301 %z = add nuw i32 %y, 1 302 %s1 = add nuw i32 %x, %z 303 %s2 = add nuw i32 %x, %y 304 %c = icmp ugt i32 %s1, %s2 305 ret i1 %c 306; CHECK: ret i1 true 307} 308 309define i1 @add6(i64 %A, i64 %B) { 310; CHECK-LABEL: @add6( 311 %s1 = add i64 %A, %B 312 %s2 = add i64 %B, %A 313 %cmp = icmp eq i64 %s1, %s2 314 ret i1 %cmp 315; CHECK: ret i1 true 316} 317 318define i1 @addpowtwo(i32 %x, i32 %y) { 319; CHECK-LABEL: @addpowtwo( 320 %l = lshr i32 %x, 1 321 %r = shl i32 1, %y 322 %s = add i32 %l, %r 323 %c = icmp eq i32 %s, 0 324 ret i1 %c 325; CHECK: ret i1 false 326} 327 328define i1 @or(i32 %x) { 329; CHECK-LABEL: @or( 330 %o = or i32 %x, 1 331 %c = icmp eq i32 %o, 0 332 ret i1 %c 333; CHECK: ret i1 false 334} 335 336define i1 @shl1(i32 %x) { 337; CHECK-LABEL: @shl1( 338 %s = shl i32 1, %x 339 %c = icmp eq i32 %s, 0 340 ret i1 %c 341; CHECK: ret i1 false 342} 343 344define i1 @shl2(i32 %X) { 345; CHECK: @shl2 346 %sub = shl nsw i32 -1, %X 347 %cmp = icmp eq i32 %sub, 31 348 ret i1 %cmp 349; CHECK-NEXT: ret i1 false 350} 351 352define i1 @shl3(i32 %X) { 353; CHECK: @shl3 354 %sub = shl nuw i32 4, %X 355 %cmp = icmp eq i32 %sub, 31 356 ret i1 %cmp 357; CHECK-NEXT: ret i1 false 358} 359 360define i1 @shl4(i32 %X) { 361; CHECK: @shl4 362 %sub = shl nsw i32 -1, %X 363 %cmp = icmp sle i32 %sub, -1 364 ret i1 %cmp 365; CHECK-NEXT: ret i1 true 366} 367 368define i1 @shl5(i32 %X) { 369; CHECK: @shl5 370 %sub = shl nuw i32 4, %X 371 %cmp = icmp ugt i32 %sub, 3 372 ret i1 %cmp 373; CHECK-NEXT: ret i1 true 374} 375 376define i1 @lshr1(i32 %x) { 377; CHECK-LABEL: @lshr1( 378 %s = lshr i32 -1, %x 379 %c = icmp eq i32 %s, 0 380 ret i1 %c 381; CHECK: ret i1 false 382} 383 384define i1 @lshr2(i32 %x) { 385; CHECK-LABEL: @lshr2( 386 %s = lshr i32 %x, 30 387 %c = icmp ugt i32 %s, 8 388 ret i1 %c 389; CHECK: ret i1 false 390} 391 392define i1 @lshr3(i32 %x) { 393; CHECK-LABEL: @lshr3( 394 %s = lshr i32 %x, %x 395 %c = icmp eq i32 %s, 0 396 ret i1 %c 397; CHECK: ret i1 true 398} 399 400define i1 @ashr1(i32 %x) { 401; CHECK-LABEL: @ashr1( 402 %s = ashr i32 -1, %x 403 %c = icmp eq i32 %s, 0 404 ret i1 %c 405; CHECK: ret i1 false 406} 407 408define i1 @ashr2(i32 %x) { 409; CHECK-LABEL: @ashr2( 410 %s = ashr i32 %x, 30 411 %c = icmp slt i32 %s, -5 412 ret i1 %c 413; CHECK: ret i1 false 414} 415 416define i1 @ashr3(i32 %x) { 417; CHECK-LABEL: @ashr3( 418 %s = ashr i32 %x, %x 419 %c = icmp eq i32 %s, 0 420 ret i1 %c 421; CHECK: ret i1 true 422} 423 424define i1 @select1(i1 %cond) { 425; CHECK-LABEL: @select1( 426 %s = select i1 %cond, i32 1, i32 0 427 %c = icmp eq i32 %s, 1 428 ret i1 %c 429; CHECK: ret i1 %cond 430} 431 432define i1 @select2(i1 %cond) { 433; CHECK-LABEL: @select2( 434 %x = zext i1 %cond to i32 435 %s = select i1 %cond, i32 %x, i32 0 436 %c = icmp ne i32 %s, 0 437 ret i1 %c 438; CHECK: ret i1 %cond 439} 440 441define i1 @select3(i1 %cond) { 442; CHECK-LABEL: @select3( 443 %x = zext i1 %cond to i32 444 %s = select i1 %cond, i32 1, i32 %x 445 %c = icmp ne i32 %s, 0 446 ret i1 %c 447; CHECK: ret i1 %cond 448} 449 450define i1 @select4(i1 %cond) { 451; CHECK-LABEL: @select4( 452 %invert = xor i1 %cond, 1 453 %s = select i1 %invert, i32 0, i32 1 454 %c = icmp ne i32 %s, 0 455 ret i1 %c 456; CHECK: ret i1 %cond 457} 458 459define i1 @select5(i32 %x) { 460; CHECK-LABEL: @select5( 461 %c = icmp eq i32 %x, 0 462 %s = select i1 %c, i32 1, i32 %x 463 %c2 = icmp eq i32 %s, 0 464 ret i1 %c2 465; CHECK: ret i1 false 466} 467 468define i1 @select6(i32 %x) { 469; CHECK-LABEL: @select6( 470 %c = icmp sgt i32 %x, 0 471 %s = select i1 %c, i32 %x, i32 4 472 %c2 = icmp eq i32 %s, 0 473 ret i1 %c2 474; CHECK: ret i1 %c2 475} 476 477define i1 @urem1(i32 %X, i32 %Y) { 478; CHECK-LABEL: @urem1( 479 %A = urem i32 %X, %Y 480 %B = icmp ult i32 %A, %Y 481 ret i1 %B 482; CHECK: ret i1 true 483} 484 485define i1 @urem2(i32 %X, i32 %Y) { 486; CHECK-LABEL: @urem2( 487 %A = urem i32 %X, %Y 488 %B = icmp eq i32 %A, %Y 489 ret i1 %B 490; CHECK: ret i1 false 491} 492 493define i1 @urem3(i32 %X) { 494; CHECK-LABEL: @urem3( 495 %A = urem i32 %X, 10 496 %B = icmp ult i32 %A, 15 497 ret i1 %B 498; CHECK: ret i1 true 499} 500 501define i1 @urem4(i32 %X) { 502; CHECK-LABEL: @urem4( 503 %A = urem i32 %X, 15 504 %B = icmp ult i32 %A, 10 505 ret i1 %B 506; CHECK: ret i1 %B 507} 508 509define i1 @urem5(i16 %X, i32 %Y) { 510; CHECK-LABEL: @urem5( 511 %A = zext i16 %X to i32 512 %B = urem i32 %A, %Y 513 %C = icmp slt i32 %B, %Y 514 ret i1 %C 515; CHECK-NOT: ret i1 true 516} 517 518define i1 @urem6(i32 %X, i32 %Y) { 519; CHECK-LABEL: @urem6( 520 %A = urem i32 %X, %Y 521 %B = icmp ugt i32 %Y, %A 522 ret i1 %B 523; CHECK: ret i1 true 524} 525 526define i1 @urem7(i32 %X) { 527; CHECK-LABEL: @urem7( 528 %A = urem i32 1, %X 529 %B = icmp sgt i32 %A, %X 530 ret i1 %B 531; CHECK-NOT: ret i1 false 532} 533 534define i1 @srem1(i32 %X) { 535; CHECK-LABEL: @srem1( 536 %A = srem i32 %X, -5 537 %B = icmp sgt i32 %A, 5 538 ret i1 %B 539; CHECK: ret i1 false 540} 541 542; PR9343 #15 543; CHECK-LABEL: @srem2( 544; CHECK: ret i1 false 545define i1 @srem2(i16 %X, i32 %Y) { 546 %A = zext i16 %X to i32 547 %B = add nsw i32 %A, 1 548 %C = srem i32 %B, %Y 549 %D = icmp slt i32 %C, 0 550 ret i1 %D 551} 552 553; CHECK-LABEL: @srem3( 554; CHECK-NEXT: ret i1 false 555define i1 @srem3(i16 %X, i32 %Y) { 556 %A = zext i16 %X to i32 557 %B = or i32 2147483648, %A 558 %C = sub nsw i32 1, %B 559 %D = srem i32 %C, %Y 560 %E = icmp slt i32 %D, 0 561 ret i1 %E 562} 563 564define i1 @udiv1(i32 %X) { 565; CHECK-LABEL: @udiv1( 566 %A = udiv i32 %X, 1000000 567 %B = icmp ult i32 %A, 5000 568 ret i1 %B 569; CHECK: ret i1 true 570} 571 572define i1 @udiv2(i32 %X, i32 %Y, i32 %Z) { 573; CHECK-LABEL: @udiv2( 574 %A = udiv exact i32 10, %Z 575 %B = udiv exact i32 20, %Z 576 %C = icmp ult i32 %A, %B 577 ret i1 %C 578; CHECK: ret i1 true 579} 580 581define i1 @udiv3(i32 %X, i32 %Y) { 582; CHECK-LABEL: @udiv3( 583 %A = udiv i32 %X, %Y 584 %C = icmp ugt i32 %A, %X 585 ret i1 %C 586; CHECK: ret i1 false 587} 588 589define i1 @udiv4(i32 %X, i32 %Y) { 590; CHECK-LABEL: @udiv4( 591 %A = udiv i32 %X, %Y 592 %C = icmp ule i32 %A, %X 593 ret i1 %C 594; CHECK: ret i1 true 595} 596 597define i1 @udiv5(i32 %X) { 598; CHECK-LABEL: @udiv5( 599 %A = udiv i32 123, %X 600 %C = icmp ugt i32 %A, 124 601 ret i1 %C 602; CHECK: ret i1 false 603} 604 605; PR11340 606define i1 @udiv6(i32 %X) nounwind { 607; CHECK-LABEL: @udiv6( 608 %A = udiv i32 1, %X 609 %C = icmp eq i32 %A, 0 610 ret i1 %C 611; CHECK: ret i1 %C 612} 613 614 615define i1 @sdiv1(i32 %X) { 616; CHECK-LABEL: @sdiv1( 617 %A = sdiv i32 %X, 1000000 618 %B = icmp slt i32 %A, 3000 619 ret i1 %B 620; CHECK: ret i1 true 621} 622 623define i1 @or1(i32 %X) { 624; CHECK-LABEL: @or1( 625 %A = or i32 %X, 62 626 %B = icmp ult i32 %A, 50 627 ret i1 %B 628; CHECK: ret i1 false 629} 630 631define i1 @and1(i32 %X) { 632; CHECK-LABEL: @and1( 633 %A = and i32 %X, 62 634 %B = icmp ugt i32 %A, 70 635 ret i1 %B 636; CHECK: ret i1 false 637} 638 639define i1 @mul1(i32 %X) { 640; CHECK-LABEL: @mul1( 641; Square of a non-zero number is non-zero if there is no overflow. 642 %Y = or i32 %X, 1 643 %M = mul nuw i32 %Y, %Y 644 %C = icmp eq i32 %M, 0 645 ret i1 %C 646; CHECK: ret i1 false 647} 648 649define i1 @mul2(i32 %X) { 650; CHECK-LABEL: @mul2( 651; Square of a non-zero number is positive if there is no signed overflow. 652 %Y = or i32 %X, 1 653 %M = mul nsw i32 %Y, %Y 654 %C = icmp sgt i32 %M, 0 655 ret i1 %C 656; CHECK: ret i1 true 657} 658 659define i1 @mul3(i32 %X, i32 %Y) { 660; CHECK-LABEL: @mul3( 661; Product of non-negative numbers is non-negative if there is no signed overflow. 662 %XX = mul nsw i32 %X, %X 663 %YY = mul nsw i32 %Y, %Y 664 %M = mul nsw i32 %XX, %YY 665 %C = icmp sge i32 %M, 0 666 ret i1 %C 667; CHECK: ret i1 true 668} 669 670define <2 x i1> @vectorselect1(<2 x i1> %cond) { 671; CHECK-LABEL: @vectorselect1( 672 %invert = xor <2 x i1> %cond, <i1 1, i1 1> 673 %s = select <2 x i1> %invert, <2 x i32> <i32 0, i32 0>, <2 x i32> <i32 1, i32 1> 674 %c = icmp ne <2 x i32> %s, <i32 0, i32 0> 675 ret <2 x i1> %c 676; CHECK: ret <2 x i1> %cond 677} 678 679; PR11948 680define <2 x i1> @vectorselectcrash(i32 %arg1) { 681 %tobool40 = icmp ne i32 %arg1, 0 682 %cond43 = select i1 %tobool40, <2 x i16> <i16 -5, i16 66>, <2 x i16> <i16 46, i16 1> 683 %cmp45 = icmp ugt <2 x i16> %cond43, <i16 73, i16 21> 684 ret <2 x i1> %cmp45 685} 686 687; PR12013 688define i1 @alloca_compare(i64 %idx) { 689 %sv = alloca { i32, i32, [124 x i32] } 690 %1 = getelementptr inbounds { i32, i32, [124 x i32] }* %sv, i32 0, i32 2, i64 %idx 691 %2 = icmp eq i32* %1, null 692 ret i1 %2 693 ; CHECK: alloca_compare 694 ; CHECK: ret i1 false 695} 696 697; PR12075 698define i1 @infinite_gep() { 699 ret i1 1 700 701unreachableblock: 702 %X = getelementptr i32 *%X, i32 1 703 %Y = icmp eq i32* %X, null 704 ret i1 %Y 705} 706 707; It's not valid to fold a comparison of an argument with an alloca, even though 708; that's tempting. An argument can't *alias* an alloca, however the aliasing rule 709; relies on restrictions against guessing an object's address and dereferencing. 710; There are no restrictions against guessing an object's address and comparing. 711 712define i1 @alloca_argument_compare(i64* %arg) { 713 %alloc = alloca i64 714 %cmp = icmp eq i64* %arg, %alloc 715 ret i1 %cmp 716 ; CHECK: alloca_argument_compare 717 ; CHECK: ret i1 %cmp 718} 719 720; As above, but with the operands reversed. 721 722define i1 @alloca_argument_compare_swapped(i64* %arg) { 723 %alloc = alloca i64 724 %cmp = icmp eq i64* %alloc, %arg 725 ret i1 %cmp 726 ; CHECK: alloca_argument_compare_swapped 727 ; CHECK: ret i1 %cmp 728} 729 730; Don't assume that a noalias argument isn't equal to a global variable's 731; address. This is an example where AliasAnalysis' NoAlias concept is 732; different from actual pointer inequality. 733 734@y = external global i32 735define zeroext i1 @external_compare(i32* noalias %x) { 736 %cmp = icmp eq i32* %x, @y 737 ret i1 %cmp 738 ; CHECK: external_compare 739 ; CHECK: ret i1 %cmp 740} 741 742define i1 @alloca_gep(i64 %a, i64 %b) { 743; CHECK-LABEL: @alloca_gep( 744; We can prove this GEP is non-null because it is inbounds and the pointer 745; is non-null. 746 %strs = alloca [1000 x [1001 x i8]], align 16 747 %x = getelementptr inbounds [1000 x [1001 x i8]]* %strs, i64 0, i64 %a, i64 %b 748 %cmp = icmp eq i8* %x, null 749 ret i1 %cmp 750; CHECK-NEXT: ret i1 false 751} 752 753define i1 @non_inbounds_gep_compare(i64* %a) { 754; CHECK-LABEL: @non_inbounds_gep_compare( 755; Equality compares with non-inbounds GEPs can be folded. 756 %x = getelementptr i64* %a, i64 42 757 %y = getelementptr inbounds i64* %x, i64 -42 758 %z = getelementptr i64* %a, i64 -42 759 %w = getelementptr inbounds i64* %z, i64 42 760 %cmp = icmp eq i64* %y, %w 761 ret i1 %cmp 762; CHECK-NEXT: ret i1 true 763} 764 765define i1 @non_inbounds_gep_compare2(i64* %a) { 766; CHECK-LABEL: @non_inbounds_gep_compare2( 767; Equality compares with non-inbounds GEPs can be folded. 768 %x = getelementptr i64* %a, i64 4294967297 769 %y = getelementptr i64* %a, i64 1 770 %cmp = icmp eq i64* %y, %y 771 ret i1 %cmp 772; CHECK-NEXT: ret i1 true 773} 774 775define <4 x i8> @vectorselectfold(<4 x i8> %a, <4 x i8> %b) { 776 %false = icmp ne <4 x i8> zeroinitializer, zeroinitializer 777 %sel = select <4 x i1> %false, <4 x i8> %a, <4 x i8> %b 778 ret <4 x i8> %sel 779 780; CHECK-LABEL: @vectorselectfold 781; CHECK-NEXT: ret <4 x i8> %b 782} 783 784define <4 x i8> @vectorselectfold2(<4 x i8> %a, <4 x i8> %b) { 785 %true = icmp eq <4 x i8> zeroinitializer, zeroinitializer 786 %sel = select <4 x i1> %true, <4 x i8> %a, <4 x i8> %b 787 ret <4 x i8> %sel 788 789; CHECK-LABEL: @vectorselectfold 790; CHECK-NEXT: ret <4 x i8> %a 791} 792 793define i1 @compare_always_true_slt(i16 %a) { 794 %1 = zext i16 %a to i32 795 %2 = sub nsw i32 0, %1 796 %3 = icmp slt i32 %2, 1 797 ret i1 %3 798 799; CHECK-LABEL: @compare_always_true_slt 800; CHECK-NEXT: ret i1 true 801} 802 803define i1 @compare_always_true_sle(i16 %a) { 804 %1 = zext i16 %a to i32 805 %2 = sub nsw i32 0, %1 806 %3 = icmp sle i32 %2, 0 807 ret i1 %3 808 809; CHECK-LABEL: @compare_always_true_sle 810; CHECK-NEXT: ret i1 true 811} 812 813define i1 @compare_always_false_sgt(i16 %a) { 814 %1 = zext i16 %a to i32 815 %2 = sub nsw i32 0, %1 816 %3 = icmp sgt i32 %2, 0 817 ret i1 %3 818 819; CHECK-LABEL: @compare_always_false_sgt 820; CHECK-NEXT: ret i1 false 821} 822 823define i1 @compare_always_false_sge(i16 %a) { 824 %1 = zext i16 %a to i32 825 %2 = sub nsw i32 0, %1 826 %3 = icmp sge i32 %2, 1 827 ret i1 %3 828 829; CHECK-LABEL: @compare_always_false_sge 830; CHECK-NEXT: ret i1 false 831} 832 833define i1 @compare_always_false_eq(i16 %a) { 834 %1 = zext i16 %a to i32 835 %2 = sub nsw i32 0, %1 836 %3 = icmp eq i32 %2, 1 837 ret i1 %3 838 839; CHECK-LABEL: @compare_always_false_eq 840; CHECK-NEXT: ret i1 false 841} 842 843define i1 @compare_always_false_ne(i16 %a) { 844 %1 = zext i16 %a to i32 845 %2 = sub nsw i32 0, %1 846 %3 = icmp ne i32 %2, 1 847 ret i1 %3 848 849; CHECK-LABEL: @compare_always_false_ne 850; CHECK-NEXT: ret i1 true 851} 852 853define i1 @compare_dividend(i32 %a) { 854 %div = sdiv i32 2, %a 855 %cmp = icmp eq i32 %div, 3 856 ret i1 %cmp 857 858; CHECK-LABEL: @compare_dividend 859; CHECK-NEXT: ret i1 false 860} 861 862define i1 @lshr_ugt_false(i32 %a) { 863 %shr = lshr i32 1, %a 864 %cmp = icmp ugt i32 %shr, 1 865 ret i1 %cmp 866; CHECK-LABEL: @lshr_ugt_false 867; CHECK-NEXT: ret i1 false 868} 869 870define i1 @exact_lshr_ugt_false(i32 %a) { 871 %shr = lshr exact i32 30, %a 872 %cmp = icmp ult i32 %shr, 15 873 ret i1 %cmp 874; CHECK-LABEL: @exact_lshr_ugt_false 875; CHECK-NEXT: ret i1 false 876} 877 878define i1 @lshr_sgt_false(i32 %a) { 879 %shr = lshr i32 1, %a 880 %cmp = icmp sgt i32 %shr, 1 881 ret i1 %cmp 882; CHECK-LABEL: @lshr_sgt_false 883; CHECK-NEXT: ret i1 false 884} 885 886define i1 @ashr_sgt_false(i32 %a) { 887 %shr = ashr i32 -30, %a 888 %cmp = icmp sgt i32 %shr, -1 889 ret i1 %cmp 890; CHECK-LABEL: @ashr_sgt_false 891; CHECK-NEXT: ret i1 false 892} 893 894define i1 @exact_ashr_sgt_false(i32 %a) { 895 %shr = ashr exact i32 -30, %a 896 %cmp = icmp sgt i32 %shr, -15 897 ret i1 %cmp 898; CHECK-LABEL: @exact_ashr_sgt_false 899; CHECK-NEXT: ret i1 false 900} 901 902define i1 @nonnull_arg(i32* nonnull %i) { 903 %cmp = icmp eq i32* %i, null 904 ret i1 %cmp 905; CHECK-LABEL: @nonnull_arg 906; CHECK: ret i1 false 907} 908 909define i1 @nonnull_deref_arg(i32* dereferenceable(4) %i) { 910 %cmp = icmp eq i32* %i, null 911 ret i1 %cmp 912; CHECK-LABEL: @nonnull_deref_arg 913; CHECK: ret i1 false 914} 915 916define i1 @nonnull_deref_as_arg(i32 addrspace(1)* dereferenceable(4) %i) { 917 %cmp = icmp eq i32 addrspace(1)* %i, null 918 ret i1 %cmp 919; CHECK-LABEL: @nonnull_deref_as_arg 920; CHECK: icmp 921; CHECK ret 922} 923 924declare nonnull i32* @returns_nonnull_helper() 925define i1 @returns_nonnull() { 926 %call = call nonnull i32* @returns_nonnull_helper() 927 %cmp = icmp eq i32* %call, null 928 ret i1 %cmp 929; CHECK-LABEL: @returns_nonnull 930; CHECK: ret i1 false 931} 932 933declare dereferenceable(4) i32* @returns_nonnull_deref_helper() 934define i1 @returns_nonnull_deref() { 935 %call = call dereferenceable(4) i32* @returns_nonnull_deref_helper() 936 %cmp = icmp eq i32* %call, null 937 ret i1 %cmp 938; CHECK-LABEL: @returns_nonnull_deref 939; CHECK: ret i1 false 940} 941 942declare dereferenceable(4) i32 addrspace(1)* @returns_nonnull_deref_as_helper() 943define i1 @returns_nonnull_as_deref() { 944 %call = call dereferenceable(4) i32 addrspace(1)* @returns_nonnull_deref_as_helper() 945 %cmp = icmp eq i32 addrspace(1)* %call, null 946 ret i1 %cmp 947; CHECK-LABEL: @returns_nonnull_as_deref 948; CHECK: icmp 949; CHECK: ret 950} 951 952define i1 @nonnull_load(i32** %addr) { 953 %ptr = load i32** %addr, !nonnull !{} 954 %cmp = icmp eq i32* %ptr, null 955 ret i1 %cmp 956; CHECK-LABEL: @nonnull_load 957; CHECK: ret i1 false 958} 959 960define i1 @nonnull_load_as_outer(i32* addrspace(1)* %addr) { 961 %ptr = load i32* addrspace(1)* %addr, !nonnull !{} 962 %cmp = icmp eq i32* %ptr, null 963 ret i1 %cmp 964; CHECK-LABEL: @nonnull_load_as_outer 965; CHECK: ret i1 false 966} 967define i1 @nonnull_load_as_inner(i32 addrspace(1)** %addr) { 968 %ptr = load i32 addrspace(1)** %addr, !nonnull !{} 969 %cmp = icmp eq i32 addrspace(1)* %ptr, null 970 ret i1 %cmp 971; CHECK-LABEL: @nonnull_load_as_inner 972; CHECK: ret i1 false 973} 974 975; If a bit is known to be zero for A and known to be one for B, 976; then A and B cannot be equal. 977define i1 @icmp_eq_const(i32 %a) nounwind { 978 %b = mul nsw i32 %a, -2 979 %c = icmp eq i32 %b, 1 980 ret i1 %c 981 982; CHECK-LABEL: @icmp_eq_const 983; CHECK-NEXT: ret i1 false 984} 985 986define i1 @icmp_ne_const(i32 %a) nounwind { 987 %b = mul nsw i32 %a, -2 988 %c = icmp ne i32 %b, 1 989 ret i1 %c 990 991; CHECK-LABEL: @icmp_ne_const 992; CHECK-NEXT: ret i1 true 993} 994 995define i1 @icmp_sdiv_int_min(i32 %a) { 996 %div = sdiv i32 -2147483648, %a 997 %cmp = icmp ne i32 %div, -1073741824 998 ret i1 %cmp 999 1000; CHECK-LABEL: @icmp_sdiv_int_min 1001; CHECK-NEXT: [[DIV:%.*]] = sdiv i32 -2147483648, %a 1002; CHECK-NEXT: [[CMP:%.*]] = icmp ne i32 [[DIV]], -1073741824 1003; CHECK-NEXT: ret i1 [[CMP]] 1004} 1005 1006define i1 @icmp_sdiv_pr20288(i64 %a) { 1007 %div = sdiv i64 %a, -8589934592 1008 %cmp = icmp ne i64 %div, 1073741824 1009 ret i1 %cmp 1010 1011; CHECK-LABEL: @icmp_sdiv_pr20288 1012; CHECK-NEXT: [[DIV:%.*]] = sdiv i64 %a, -8589934592 1013; CHECK-NEXT: [[CMP:%.*]] = icmp ne i64 [[DIV]], 1073741824 1014; CHECK-NEXT: ret i1 [[CMP]] 1015} 1016 1017define i1 @icmp_sdiv_neg1(i64 %a) { 1018 %div = sdiv i64 %a, -1 1019 %cmp = icmp ne i64 %div, 1073741824 1020 ret i1 %cmp 1021 1022; CHECK-LABEL: @icmp_sdiv_neg1 1023; CHECK-NEXT: [[DIV:%.*]] = sdiv i64 %a, -1 1024; CHECK-NEXT: [[CMP:%.*]] = icmp ne i64 [[DIV]], 1073741824 1025; CHECK-NEXT: ret i1 [[CMP]] 1026} 1027 1028define i1 @icmp_known_bits(i4 %x, i4 %y) { 1029 %and1 = and i4 %y, -7 1030 %and2 = and i4 %x, -7 1031 %or1 = or i4 %and1, 2 1032 %or2 = or i4 %and2, 2 1033 %add = add i4 %or1, %or2 1034 %cmp = icmp eq i4 %add, 0 1035 ret i1 %cmp 1036 1037; CHECK-LABEL: @icmp_known_bits 1038; CHECK-NEXT: ret i1 false 1039} 1040 1041define i1 @icmp_shl_nuw_1(i64 %a) { 1042 %shl = shl nuw i64 1, %a 1043 %cmp = icmp ne i64 %shl, 0 1044 ret i1 %cmp 1045 1046; CHECK-LABEL: @icmp_shl_nuw_1 1047; CHECK-NEXT: ret i1 true 1048} 1049 1050define i1 @icmp_shl_nsw_neg1(i64 %a) { 1051 %shl = shl nsw i64 -1, %a 1052 %cmp = icmp sge i64 %shl, 3 1053 ret i1 %cmp 1054 1055; CHECK-LABEL: @icmp_shl_nsw_neg1 1056; CHECK-NEXT: ret i1 false 1057} 1058 1059define i1 @icmp_shl_nsw_1(i64 %a) { 1060 %shl = shl nsw i64 1, %a 1061 %cmp = icmp sge i64 %shl, 0 1062 ret i1 %cmp 1063 1064; CHECK-LABEL: @icmp_shl_nsw_1 1065; CHECK-NEXT: ret i1 true 1066} 1067 1068define i1 @icmp_shl_1_V_ugt_2147483648(i32 %V) { 1069 %shl = shl i32 1, %V 1070 %cmp = icmp ugt i32 %shl, 2147483648 1071 ret i1 %cmp 1072 1073; CHECK-LABEL: @icmp_shl_1_V_ugt_2147483648( 1074; CHECK-NEXT: ret i1 false 1075} 1076 1077define i1 @icmp_shl_1_V_ule_2147483648(i32 %V) { 1078 %shl = shl i32 1, %V 1079 %cmp = icmp ule i32 %shl, 2147483648 1080 ret i1 %cmp 1081 1082; CHECK-LABEL: @icmp_shl_1_V_ule_2147483648( 1083; CHECK-NEXT: ret i1 true 1084} 1085 1086define i1 @icmp_shl_1_V_eq_31(i32 %V) { 1087 %shl = shl i32 1, %V 1088 %cmp = icmp eq i32 %shl, 31 1089 ret i1 %cmp 1090 1091; CHECK-LABEL: @icmp_shl_1_V_eq_31( 1092; CHECK-NEXT: ret i1 false 1093} 1094 1095define i1 @icmp_shl_1_V_ne_31(i32 %V) { 1096 %shl = shl i32 1, %V 1097 %cmp = icmp ne i32 %shl, 31 1098 ret i1 %cmp 1099 1100; CHECK-LABEL: @icmp_shl_1_V_ne_31( 1101; CHECK-NEXT: ret i1 true 1102} 1103 1104define i1 @tautological1(i32 %A, i32 %B) { 1105 %C = and i32 %A, %B 1106 %D = icmp ugt i32 %C, %A 1107 ret i1 %D 1108; CHECK-LABEL: @tautological1( 1109; CHECK: ret i1 false 1110} 1111 1112define i1 @tautological2(i32 %A, i32 %B) { 1113 %C = and i32 %A, %B 1114 %D = icmp ule i32 %C, %A 1115 ret i1 %D 1116; CHECK-LABEL: @tautological2( 1117; CHECK: ret i1 true 1118} 1119 1120define i1 @tautological3(i32 %A, i32 %B) { 1121 %C = or i32 %A, %B 1122 %D = icmp ule i32 %A, %C 1123 ret i1 %D 1124; CHECK-LABEL: @tautological3( 1125; CHECK: ret i1 true 1126} 1127 1128define i1 @tautological4(i32 %A, i32 %B) { 1129 %C = or i32 %A, %B 1130 %D = icmp ugt i32 %A, %C 1131 ret i1 %D 1132; CHECK-LABEL: @tautological4( 1133; CHECK: ret i1 false 1134} 1135 1136define i1 @tautological5(i32 %A, i32 %B) { 1137 %C = or i32 %A, %B 1138 %D = icmp ult i32 %C, %A 1139 ret i1 %D 1140; CHECK-LABEL: @tautological5( 1141; CHECK: ret i1 false 1142} 1143 1144define i1 @tautological6(i32 %A, i32 %B) { 1145 %C = or i32 %A, %B 1146 %D = icmp uge i32 %C, %A 1147 ret i1 %D 1148; CHECK-LABEL: @tautological6( 1149; CHECK: ret i1 true 1150} 1151 1152define i1 @tautological7(i32 %A, i32 %B) { 1153 %C = and i32 %A, %B 1154 %D = icmp uge i32 %A, %C 1155 ret i1 %D 1156; CHECK-LABEL: @tautological7( 1157; CHECK: ret i1 true 1158} 1159 1160define i1 @tautological8(i32 %A, i32 %B) { 1161 %C = and i32 %A, %B 1162 %D = icmp ult i32 %A, %C 1163 ret i1 %D 1164; CHECK-LABEL: @tautological8( 1165; CHECK: ret i1 false 1166} 1167