1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py 2; RUN: opt -indvars -S < %s | FileCheck %s 3 4target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64" 5 6@X = external global [0 x double] 7 8; Indvars should be able to simplify simple comparisons involving 9; induction variables. 10 11define void @foo(i64 %n, i32* nocapture %p) nounwind { 12; CHECK-LABEL: @foo( 13; CHECK-NEXT: entry: 14; CHECK-NEXT: [[CMP9:%.*]] = icmp sgt i64 [[N:%.*]], 0 15; CHECK-NEXT: br i1 [[CMP9]], label [[PRE:%.*]], label [[RETURN:%.*]] 16; CHECK: pre: 17; CHECK-NEXT: [[T3:%.*]] = load i32, i32* [[P:%.*]], align 4 18; CHECK-NEXT: [[TOBOOL_NOT:%.*]] = icmp ne i32 [[T3]], 0 19; CHECK-NEXT: br label [[LOOP:%.*]] 20; CHECK: loop: 21; CHECK-NEXT: [[I:%.*]] = phi i64 [ 0, [[PRE]] ], [ [[INC:%.*]], [[FOR_INC:%.*]] ] 22; CHECK-NEXT: [[COND:%.*]] = and i1 [[TOBOOL_NOT]], true 23; CHECK-NEXT: br i1 [[COND]], label [[IF_THEN:%.*]], label [[FOR_INC]] 24; CHECK: if.then: 25; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr [0 x double], [0 x double]* @X, i64 0, i64 [[I]] 26; CHECK-NEXT: store double 3.200000e+00, double* [[ARRAYIDX]], align 8 27; CHECK-NEXT: br label [[FOR_INC]] 28; CHECK: for.inc: 29; CHECK-NEXT: [[INC]] = add nuw nsw i64 [[I]], 1 30; CHECK-NEXT: [[EXITCOND1:%.*]] = icmp eq i64 [[INC]], [[N]] 31; CHECK-NEXT: br i1 [[EXITCOND1]], label [[RETURN_LOOPEXIT:%.*]], label [[LOOP]] 32; CHECK: return.loopexit: 33; CHECK-NEXT: br label [[RETURN]] 34; CHECK: return: 35; CHECK-NEXT: ret void 36; 37entry: 38 %cmp9 = icmp sgt i64 %n, 0 39 br i1 %cmp9, label %pre, label %return 40 41pre: 42 %t3 = load i32, i32* %p 43 %tobool.not = icmp ne i32 %t3, 0 44 br label %loop 45 46loop: 47 %i = phi i64 [ 0, %pre ], [ %inc, %for.inc ] 48 %cmp6 = icmp slt i64 %i, %n 49 %cond = and i1 %tobool.not, %cmp6 50 br i1 %cond, label %if.then, label %for.inc 51 52if.then: 53 %arrayidx = getelementptr [0 x double], [0 x double]* @X, i64 0, i64 %i 54 store double 3.200000e+00, double* %arrayidx 55 br label %for.inc 56 57for.inc: 58 %inc = add nsw i64 %i, 1 59 %exitcond = icmp sge i64 %inc, %n 60 br i1 %exitcond, label %return, label %loop 61 62return: 63 ret void 64} 65 66; Don't eliminate an icmp that's contributing to the loop exit test though. 67 68define i32 @_ZNK4llvm5APInt3ultERKS0_(i32 %tmp2.i1, i64** %tmp65, i64** %tmp73, i64** %tmp82, i64** %tmp90) { 69; CHECK-LABEL: @_ZNK4llvm5APInt3ultERKS0_( 70; CHECK-NEXT: entry: 71; CHECK-NEXT: br label [[BB18:%.*]] 72; CHECK: bb13: 73; CHECK-NEXT: [[TMP66:%.*]] = load i64*, i64** [[TMP65:%.*]], align 4 74; CHECK-NEXT: [[TMP68:%.*]] = getelementptr inbounds i64, i64* [[TMP66]], i32 [[I:%.*]] 75; CHECK-NEXT: [[TMP69:%.*]] = load i64, i64* [[TMP68]], align 4 76; CHECK-NEXT: [[TMP74:%.*]] = load i64*, i64** [[TMP73:%.*]], align 4 77; CHECK-NEXT: [[TMP76:%.*]] = getelementptr inbounds i64, i64* [[TMP74]], i32 [[I]] 78; CHECK-NEXT: [[TMP77:%.*]] = load i64, i64* [[TMP76]], align 4 79; CHECK-NEXT: [[TMP78:%.*]] = icmp ugt i64 [[TMP69]], [[TMP77]] 80; CHECK-NEXT: br i1 [[TMP78]], label [[BB20_LOOPEXIT:%.*]], label [[BB15:%.*]] 81; CHECK: bb15: 82; CHECK-NEXT: [[TMP83:%.*]] = load i64*, i64** [[TMP82:%.*]], align 4 83; CHECK-NEXT: [[TMP85:%.*]] = getelementptr inbounds i64, i64* [[TMP83]], i32 [[I]] 84; CHECK-NEXT: [[TMP86:%.*]] = load i64, i64* [[TMP85]], align 4 85; CHECK-NEXT: [[TMP91:%.*]] = load i64*, i64** [[TMP90:%.*]], align 4 86; CHECK-NEXT: [[TMP93:%.*]] = getelementptr inbounds i64, i64* [[TMP91]], i32 [[I]] 87; CHECK-NEXT: [[TMP94:%.*]] = load i64, i64* [[TMP93]], align 4 88; CHECK-NEXT: [[TMP95:%.*]] = icmp ult i64 [[TMP86]], [[TMP94]] 89; CHECK-NEXT: br i1 [[TMP95]], label [[BB20_LOOPEXIT]], label [[BB17:%.*]] 90; CHECK: bb17: 91; CHECK-NEXT: [[TMP97:%.*]] = add nsw i32 [[I]], -1 92; CHECK-NEXT: br label [[BB18]] 93; CHECK: bb18: 94; CHECK-NEXT: [[I]] = phi i32 [ [[TMP2_I1:%.*]], [[ENTRY:%.*]] ], [ [[TMP97]], [[BB17]] ] 95; CHECK-NEXT: [[TMP99:%.*]] = icmp sgt i32 [[I]], -1 96; CHECK-NEXT: br i1 [[TMP99]], label [[BB13:%.*]], label [[BB20_LOOPEXIT]] 97; CHECK: bb20.loopexit: 98; CHECK-NEXT: [[TMP_0_PH:%.*]] = phi i32 [ 0, [[BB18]] ], [ 1, [[BB15]] ], [ 0, [[BB13]] ] 99; CHECK-NEXT: ret i32 [[TMP_0_PH]] 100; 101entry: 102 br label %bb18 103 104bb13: 105 %tmp66 = load i64*, i64** %tmp65, align 4 106 %tmp68 = getelementptr inbounds i64, i64* %tmp66, i32 %i 107 %tmp69 = load i64, i64* %tmp68, align 4 108 %tmp74 = load i64*, i64** %tmp73, align 4 109 %tmp76 = getelementptr inbounds i64, i64* %tmp74, i32 %i 110 %tmp77 = load i64, i64* %tmp76, align 4 111 %tmp78 = icmp ugt i64 %tmp69, %tmp77 112 br i1 %tmp78, label %bb20.loopexit, label %bb15 113 114bb15: 115 %tmp83 = load i64*, i64** %tmp82, align 4 116 %tmp85 = getelementptr inbounds i64, i64* %tmp83, i32 %i 117 %tmp86 = load i64, i64* %tmp85, align 4 118 %tmp91 = load i64*, i64** %tmp90, align 4 119 %tmp93 = getelementptr inbounds i64, i64* %tmp91, i32 %i 120 %tmp94 = load i64, i64* %tmp93, align 4 121 %tmp95 = icmp ult i64 %tmp86, %tmp94 122 br i1 %tmp95, label %bb20.loopexit, label %bb17 123 124bb17: 125 %tmp97 = add nsw i32 %i, -1 126 br label %bb18 127 128bb18: 129 %i = phi i32 [ %tmp2.i1, %entry ], [ %tmp97, %bb17 ] 130 %tmp99 = icmp sgt i32 %i, -1 131 br i1 %tmp99, label %bb13, label %bb20.loopexit 132 133bb20.loopexit: 134 %tmp.0.ph = phi i32 [ 0, %bb18 ], [ 1, %bb15 ], [ 0, %bb13 ] 135 ret i32 %tmp.0.ph 136} 137 138; Indvars should eliminate the icmp here. 139 140 141define void @func_10() nounwind { 142; CHECK-LABEL: @func_10( 143; CHECK-NEXT: entry: 144; CHECK-NEXT: br label [[LOOP:%.*]] 145; CHECK: loop: 146; CHECK-NEXT: store i64 0, i64* null, align 8 147; CHECK-NEXT: br i1 false, label [[LOOP]], label [[RETURN:%.*]] 148; CHECK: return: 149; CHECK-NEXT: ret void 150; 151entry: 152 br label %loop 153 154loop: 155 %i = phi i32 [ %i.next, %loop ], [ 0, %entry ] 156 %t0 = icmp slt i32 %i, 0 157 %t1 = zext i1 %t0 to i32 158 %t2 = add i32 %t1, %i 159 %u3 = zext i32 %t2 to i64 160 store i64 %u3, i64* null 161 %i.next = add i32 %i, 1 162 br i1 undef, label %loop, label %return 163 164return: 165 ret void 166} 167 168; PR14432 169; Indvars should not turn the second loop into an infinite one. 170 171 172define i32 @func_11() nounwind uwtable { 173; CHECK-LABEL: @func_11( 174; CHECK-NEXT: entry: 175; CHECK-NEXT: br label [[FORCOND:%.*]] 176; CHECK: forcond: 177; CHECK-NEXT: br i1 false, label [[NOASSERT:%.*]], label [[FORCOND38_PREHEADER:%.*]] 178; CHECK: forcond38.preheader: 179; CHECK-NEXT: br label [[FORCOND38:%.*]] 180; CHECK: noassert: 181; CHECK-NEXT: br i1 true, label [[FORCOND]], label [[ASSERT33:%.*]] 182; CHECK: assert33: 183; CHECK-NEXT: tail call void @llvm.trap() 184; CHECK-NEXT: unreachable 185; CHECK: forcond38: 186; CHECK-NEXT: br i1 false, label [[NOASSERT68:%.*]], label [[UNROLLEDEND:%.*]] 187; CHECK: noassert68: 188; CHECK-NEXT: br i1 true, label [[FORCOND38]], label [[ASSERT77:%.*]] 189; CHECK: assert77: 190; CHECK-NEXT: tail call void @llvm.trap() 191; CHECK-NEXT: unreachable 192; CHECK: unrolledend: 193; CHECK-NEXT: ret i32 0 194; 195entry: 196 br label %forcond 197 198forcond: ; preds = %noassert, %entry 199 %__key6.0 = phi i32 [ 2, %entry ], [ %tmp37, %noassert ] 200 %tmp5 = icmp slt i32 %__key6.0, 10 201 br i1 %tmp5, label %noassert, label %forcond38.preheader 202 203forcond38.preheader: ; preds = %forcond 204 br label %forcond38 205 206noassert: ; preds = %forbody 207 %tmp13 = sdiv i32 -32768, %__key6.0 208 %tmp2936 = shl i32 %tmp13, 24 209 %sext23 = shl i32 %tmp13, 24 210 %tmp32 = icmp eq i32 %tmp2936, %sext23 211 %tmp37 = add i32 %__key6.0, 1 212 br i1 %tmp32, label %forcond, label %assert33 213 214assert33: ; preds = %noassert 215 tail call void @llvm.trap() 216 unreachable 217 218forcond38: ; preds = %noassert68, %forcond38.preheader 219 %__key8.0 = phi i32 [ %tmp81, %noassert68 ], [ 2, %forcond38.preheader ] 220 %tmp46 = icmp slt i32 %__key8.0, 10 221 br i1 %tmp46, label %noassert68, label %unrolledend 222 223noassert68: ; preds = %forbody39 224 %tmp57 = sdiv i32 -32768, %__key8.0 225 %sext34 = shl i32 %tmp57, 16 226 %sext21 = shl i32 %tmp57, 16 227 %tmp76 = icmp eq i32 %sext34, %sext21 228 %tmp81 = add i32 %__key8.0, 1 229 br i1 %tmp76, label %forcond38, label %assert77 230 231assert77: ; preds = %noassert68 232 tail call void @llvm.trap() 233 unreachable 234 235unrolledend: ; preds = %forcond38 236 ret i32 0 237} 238 239define i32 @func_11_flipped() nounwind uwtable { 240; CHECK-LABEL: @func_11_flipped( 241; CHECK-NEXT: entry: 242; CHECK-NEXT: br label [[FORCOND:%.*]] 243; CHECK: forcond: 244; CHECK-NEXT: br i1 true, label [[FORCOND38_PREHEADER:%.*]], label [[NOASSERT:%.*]] 245; CHECK: forcond38.preheader: 246; CHECK-NEXT: br label [[FORCOND38:%.*]] 247; CHECK: noassert: 248; CHECK-NEXT: br i1 true, label [[FORCOND]], label [[ASSERT33:%.*]] 249; CHECK: assert33: 250; CHECK-NEXT: tail call void @llvm.trap() 251; CHECK-NEXT: unreachable 252; CHECK: forcond38: 253; CHECK-NEXT: br i1 false, label [[NOASSERT68:%.*]], label [[UNROLLEDEND:%.*]] 254; CHECK: noassert68: 255; CHECK-NEXT: br i1 true, label [[FORCOND38]], label [[ASSERT77:%.*]] 256; CHECK: assert77: 257; CHECK-NEXT: tail call void @llvm.trap() 258; CHECK-NEXT: unreachable 259; CHECK: unrolledend: 260; CHECK-NEXT: ret i32 0 261; 262entry: 263 br label %forcond 264 265forcond: ; preds = %noassert, %entry 266 %__key6.0 = phi i32 [ 2, %entry ], [ %tmp37, %noassert ] 267 %tmp5 = icmp sge i32 %__key6.0, 10 268 br i1 %tmp5, label %forcond38.preheader, label %noassert 269 270forcond38.preheader: ; preds = %forcond 271 br label %forcond38 272 273noassert: ; preds = %forbody 274 %tmp13 = sdiv i32 -32768, %__key6.0 275 %tmp2936 = shl i32 %tmp13, 24 276 %sext23 = shl i32 %tmp13, 24 277 %tmp32 = icmp eq i32 %tmp2936, %sext23 278 %tmp37 = add i32 %__key6.0, 1 279 br i1 %tmp32, label %forcond, label %assert33 280 281assert33: ; preds = %noassert 282 tail call void @llvm.trap() 283 unreachable 284 285forcond38: ; preds = %noassert68, %forcond38.preheader 286 %__key8.0 = phi i32 [ %tmp81, %noassert68 ], [ 2, %forcond38.preheader ] 287 %tmp46 = icmp slt i32 %__key8.0, 10 288 br i1 %tmp46, label %noassert68, label %unrolledend 289 290noassert68: ; preds = %forbody39 291 %tmp57 = sdiv i32 -32768, %__key8.0 292 %sext34 = shl i32 %tmp57, 16 293 %sext21 = shl i32 %tmp57, 16 294 %tmp76 = icmp eq i32 %sext34, %sext21 295 %tmp81 = add i32 %__key8.0, 1 296 br i1 %tmp76, label %forcond38, label %assert77 297 298assert77: ; preds = %noassert68 299 tail call void @llvm.trap() 300 unreachable 301 302unrolledend: ; preds = %forcond38 303 ret i32 0 304} 305 306declare void @llvm.trap() noreturn nounwind 307 308; In this case the second loop only has a single iteration, fold the header away 309define i32 @func_12() nounwind uwtable { 310; CHECK-LABEL: @func_12( 311; CHECK-NEXT: entry: 312; CHECK-NEXT: br label [[FORCOND:%.*]] 313; CHECK: forcond: 314; CHECK-NEXT: br i1 false, label [[NOASSERT:%.*]], label [[FORCOND38_PREHEADER:%.*]] 315; CHECK: forcond38.preheader: 316; CHECK-NEXT: br label [[FORCOND38:%.*]] 317; CHECK: noassert: 318; CHECK-NEXT: br i1 true, label [[FORCOND]], label [[ASSERT33:%.*]] 319; CHECK: assert33: 320; CHECK-NEXT: tail call void @llvm.trap() 321; CHECK-NEXT: unreachable 322; CHECK: forcond38: 323; CHECK-NEXT: br i1 true, label [[NOASSERT68:%.*]], label [[UNROLLEDEND:%.*]] 324; CHECK: noassert68: 325; CHECK-NEXT: br i1 false, label [[FORCOND38]], label [[ASSERT77:%.*]] 326; CHECK: assert77: 327; CHECK-NEXT: tail call void @llvm.trap() 328; CHECK-NEXT: unreachable 329; CHECK: unrolledend: 330; CHECK-NEXT: ret i32 0 331; 332entry: 333 br label %forcond 334 335forcond: ; preds = %noassert, %entry 336 %__key6.0 = phi i32 [ 2, %entry ], [ %tmp37, %noassert ] 337 %tmp5 = icmp slt i32 %__key6.0, 10 338 br i1 %tmp5, label %noassert, label %forcond38.preheader 339 340forcond38.preheader: ; preds = %forcond 341 br label %forcond38 342 343noassert: ; preds = %forbody 344 %tmp13 = sdiv i32 -32768, %__key6.0 345 %tmp2936 = shl i32 %tmp13, 24 346 %sext23 = shl i32 %tmp13, 24 347 %tmp32 = icmp eq i32 %tmp2936, %sext23 348 %tmp37 = add i32 %__key6.0, 1 349 br i1 %tmp32, label %forcond, label %assert33 350 351assert33: ; preds = %noassert 352 tail call void @llvm.trap() 353 unreachable 354 355forcond38: ; preds = %noassert68, %forcond38.preheader 356 %__key8.0 = phi i32 [ %tmp81, %noassert68 ], [ 2, %forcond38.preheader ] 357 %tmp46 = icmp slt i32 %__key8.0, 10 358 br i1 %tmp46, label %noassert68, label %unrolledend 359 360noassert68: ; preds = %forbody39 361 %tmp57 = sdiv i32 -32768, %__key8.0 362 %sext34 = shl i32 %tmp57, 16 363 %sext21 = shl i32 %tmp57, 16 364 %tmp76 = icmp ne i32 %sext34, %sext21 365 %tmp81 = add i32 %__key8.0, 1 366 br i1 %tmp76, label %forcond38, label %assert77 367 368assert77: ; preds = %noassert68 369 tail call void @llvm.trap() 370 unreachable 371 372unrolledend: ; preds = %forcond38 373 ret i32 0 374} 375 376declare void @side_effect() 377 378define void @func_13(i32* %len.ptr) { 379; CHECK-LABEL: @func_13( 380; CHECK-NEXT: entry: 381; CHECK-NEXT: [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4, !range [[RNG0:![0-9]+]] 382; CHECK-NEXT: [[LEN_IS_ZERO:%.*]] = icmp eq i32 [[LEN]], 0 383; CHECK-NEXT: br i1 [[LEN_IS_ZERO]], label [[LEAVE:%.*]], label [[LOOP_PREHEADER:%.*]] 384; CHECK: loop.preheader: 385; CHECK-NEXT: br label [[LOOP:%.*]] 386; CHECK: loop: 387; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_INC:%.*]], [[BE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ] 388; CHECK-NEXT: call void @side_effect() 389; CHECK-NEXT: [[IV_INC]] = add nuw nsw i32 [[IV]], 1 390; CHECK-NEXT: br i1 true, label [[BE]], label [[LEAVE_LOOPEXIT:%.*]] 391; CHECK: be: 392; CHECK-NEXT: call void @side_effect() 393; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV_INC]], [[LEN]] 394; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[LEAVE_LOOPEXIT]] 395; CHECK: leave.loopexit: 396; CHECK-NEXT: br label [[LEAVE]] 397; CHECK: leave: 398; CHECK-NEXT: ret void 399; 400entry: 401 %len = load i32, i32* %len.ptr, !range !0 402 %len.sub.1 = add i32 %len, -1 403 %len.is.zero = icmp eq i32 %len, 0 404 br i1 %len.is.zero, label %leave, label %loop 405 406loop: 407 %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] 408 call void @side_effect() 409 %iv.inc = add i32 %iv, 1 410 %iv.cmp = icmp ult i32 %iv, %len 411 br i1 %iv.cmp, label %be, label %leave 412 413be: 414 call void @side_effect() 415 %be.cond = icmp ult i32 %iv, %len.sub.1 416 br i1 %be.cond, label %loop, label %leave 417 418leave: 419 ret void 420} 421 422define void @func_14(i32* %len.ptr) { 423; CHECK-LABEL: @func_14( 424; CHECK-NEXT: entry: 425; CHECK-NEXT: [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4, !range [[RNG0]] 426; CHECK-NEXT: [[LEN_IS_ZERO:%.*]] = icmp eq i32 [[LEN]], 0 427; CHECK-NEXT: [[LEN_IS_INT_MIN:%.*]] = icmp eq i32 [[LEN]], -2147483648 428; CHECK-NEXT: [[NO_ENTRY:%.*]] = or i1 [[LEN_IS_ZERO]], [[LEN_IS_INT_MIN]] 429; CHECK-NEXT: br i1 [[NO_ENTRY]], label [[LEAVE:%.*]], label [[LOOP_PREHEADER:%.*]] 430; CHECK: loop.preheader: 431; CHECK-NEXT: br label [[LOOP:%.*]] 432; CHECK: loop: 433; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_INC:%.*]], [[BE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ] 434; CHECK-NEXT: call void @side_effect() 435; CHECK-NEXT: [[IV_INC]] = add nuw nsw i32 [[IV]], 1 436; CHECK-NEXT: br i1 true, label [[BE]], label [[LEAVE_LOOPEXIT:%.*]] 437; CHECK: be: 438; CHECK-NEXT: call void @side_effect() 439; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV_INC]], [[LEN]] 440; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[LEAVE_LOOPEXIT]] 441; CHECK: leave.loopexit: 442; CHECK-NEXT: br label [[LEAVE]] 443; CHECK: leave: 444; CHECK-NEXT: ret void 445; 446entry: 447 %len = load i32, i32* %len.ptr, !range !0 448 %len.sub.1 = add i32 %len, -1 449 %len.is.zero = icmp eq i32 %len, 0 450 %len.is.int_min = icmp eq i32 %len, 2147483648 451 %no.entry = or i1 %len.is.zero, %len.is.int_min 452 br i1 %no.entry, label %leave, label %loop 453 454loop: 455 %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] 456 call void @side_effect() 457 %iv.inc = add i32 %iv, 1 458 %iv.cmp = icmp slt i32 %iv, %len 459 br i1 %iv.cmp, label %be, label %leave 460 461be: 462 call void @side_effect() 463 %be.cond = icmp slt i32 %iv, %len.sub.1 464 br i1 %be.cond, label %loop, label %leave 465 466leave: 467 ret void 468} 469 470define void @func_15(i32* %len.ptr) { 471; CHECK-LABEL: @func_15( 472; CHECK-NEXT: entry: 473; CHECK-NEXT: [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4, !range [[RNG0]] 474; CHECK-NEXT: [[LEN_ADD_1:%.*]] = add i32 [[LEN]], 1 475; CHECK-NEXT: [[LEN_ADD_1_IS_ZERO:%.*]] = icmp eq i32 [[LEN_ADD_1]], 0 476; CHECK-NEXT: br i1 [[LEN_ADD_1_IS_ZERO]], label [[LEAVE:%.*]], label [[LOOP_PREHEADER:%.*]] 477; CHECK: loop.preheader: 478; CHECK-NEXT: br label [[LOOP:%.*]] 479; CHECK: loop: 480; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_INC:%.*]], [[BE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ] 481; CHECK-NEXT: call void @side_effect() 482; CHECK-NEXT: [[IV_INC]] = add nuw nsw i32 [[IV]], 1 483; CHECK-NEXT: br i1 true, label [[BE]], label [[LEAVE_LOOPEXIT:%.*]] 484; CHECK: be: 485; CHECK-NEXT: call void @side_effect() 486; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV_INC]], [[LEN_ADD_1]] 487; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[LEAVE_LOOPEXIT]] 488; CHECK: leave.loopexit: 489; CHECK-NEXT: br label [[LEAVE]] 490; CHECK: leave: 491; CHECK-NEXT: ret void 492; 493entry: 494 %len = load i32, i32* %len.ptr, !range !0 495 %len.add.1 = add i32 %len, 1 496 %len.add.1.is.zero = icmp eq i32 %len.add.1, 0 497 br i1 %len.add.1.is.zero, label %leave, label %loop 498 499loop: 500 %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] 501 call void @side_effect() 502 %iv.inc = add i32 %iv, 1 503 %iv.cmp = icmp ult i32 %iv, %len.add.1 504 br i1 %iv.cmp, label %be, label %leave 505 506be: 507 call void @side_effect() 508 %be.cond = icmp ult i32 %iv, %len 509 br i1 %be.cond, label %loop, label %leave 510 511leave: 512 ret void 513} 514 515define void @func_16(i32* %len.ptr) { 516; CHECK-LABEL: @func_16( 517; CHECK-NEXT: entry: 518; CHECK-NEXT: [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4, !range [[RNG0]] 519; CHECK-NEXT: [[LEN_ADD_5:%.*]] = add i32 [[LEN]], 5 520; CHECK-NEXT: [[ENTRY_COND_0:%.*]] = icmp slt i32 [[LEN]], 2147483643 521; CHECK-NEXT: [[ENTRY_COND_1:%.*]] = icmp slt i32 4, [[LEN_ADD_5]] 522; CHECK-NEXT: [[ENTRY_COND:%.*]] = and i1 [[ENTRY_COND_0]], [[ENTRY_COND_1]] 523; CHECK-NEXT: br i1 [[ENTRY_COND]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]] 524; CHECK: loop.preheader: 525; CHECK-NEXT: [[TMP0:%.*]] = add nuw nsw i32 [[LEN]], 1 526; CHECK-NEXT: br label [[LOOP:%.*]] 527; CHECK: loop: 528; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_INC:%.*]], [[BE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ] 529; CHECK-NEXT: call void @side_effect() 530; CHECK-NEXT: [[IV_INC]] = add nuw nsw i32 [[IV]], 1 531; CHECK-NEXT: br i1 true, label [[BE]], label [[LEAVE_LOOPEXIT:%.*]] 532; CHECK: be: 533; CHECK-NEXT: call void @side_effect() 534; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV_INC]], [[TMP0]] 535; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[LEAVE_LOOPEXIT]] 536; CHECK: leave.loopexit: 537; CHECK-NEXT: br label [[LEAVE]] 538; CHECK: leave: 539; CHECK-NEXT: ret void 540; 541entry: 542 %len = load i32, i32* %len.ptr, !range !0 543 %len.add.5 = add i32 %len, 5 544 %entry.cond.0 = icmp slt i32 %len, 2147483643 545 %entry.cond.1 = icmp slt i32 4, %len.add.5 546 %entry.cond = and i1 %entry.cond.0, %entry.cond.1 547 br i1 %entry.cond, label %loop, label %leave 548 549loop: 550 %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] 551 call void @side_effect() 552 %iv.inc = add i32 %iv, 1 553 %iv.add.4 = add i32 %iv, 4 554 %iv.cmp = icmp slt i32 %iv.add.4, %len.add.5 555 br i1 %iv.cmp, label %be, label %leave 556 557be: 558 call void @side_effect() 559 %be.cond = icmp slt i32 %iv, %len 560 br i1 %be.cond, label %loop, label %leave 561 562leave: 563 ret void 564} 565 566define void @func_17(i32* %len.ptr) { 567; CHECK-LABEL: @func_17( 568; CHECK-NEXT: entry: 569; CHECK-NEXT: [[LEN:%.*]] = load i32, i32* [[LEN_PTR:%.*]], align 4 570; CHECK-NEXT: [[LEN_ADD_5:%.*]] = add i32 [[LEN]], -5 571; CHECK-NEXT: [[ENTRY_COND_0:%.*]] = icmp slt i32 [[LEN]], -2147483643 572; CHECK-NEXT: [[ENTRY_COND_1:%.*]] = icmp slt i32 -6, [[LEN_ADD_5]] 573; CHECK-NEXT: [[ENTRY_COND:%.*]] = and i1 [[ENTRY_COND_0]], [[ENTRY_COND_1]] 574; CHECK-NEXT: br i1 [[ENTRY_COND]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]] 575; CHECK: loop.preheader: 576; CHECK-NEXT: [[SMAX:%.*]] = call i32 @llvm.smax.i32(i32 [[LEN]], i32 0) 577; CHECK-NEXT: [[TMP0:%.*]] = add nsw i32 [[SMAX]], -5 578; CHECK-NEXT: br label [[LOOP:%.*]] 579; CHECK: loop: 580; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_INC:%.*]], [[BE:%.*]] ], [ -6, [[LOOP_PREHEADER]] ] 581; CHECK-NEXT: call void @side_effect() 582; CHECK-NEXT: [[IV_INC]] = add nsw i32 [[IV]], 1 583; CHECK-NEXT: br i1 true, label [[BE]], label [[LEAVE_LOOPEXIT:%.*]] 584; CHECK: be: 585; CHECK-NEXT: call void @side_effect() 586; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV_INC]], [[TMP0]] 587; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[LEAVE_LOOPEXIT]] 588; CHECK: leave.loopexit: 589; CHECK-NEXT: br label [[LEAVE]] 590; CHECK: leave: 591; CHECK-NEXT: ret void 592; 593entry: 594 %len = load i32, i32* %len.ptr 595 %len.add.5 = add i32 %len, -5 596 %entry.cond.0 = icmp slt i32 %len, 2147483653 ;; 2147483653 == INT_MIN - (-5) 597 %entry.cond.1 = icmp slt i32 -6, %len.add.5 598 %entry.cond = and i1 %entry.cond.0, %entry.cond.1 599 br i1 %entry.cond, label %loop, label %leave 600 601loop: 602 %iv.2 = phi i32 [ 0, %entry ], [ %iv.2.inc, %be ] 603 %iv = phi i32 [ -6, %entry ], [ %iv.inc, %be ] 604 call void @side_effect() 605 %iv.inc = add i32 %iv, 1 606 %iv.2.inc = add i32 %iv.2, 1 607 %iv.cmp = icmp slt i32 %iv, %len.add.5 608 609; Deduces {-5,+,1} s< (-5 + %len) from {0,+,1} < %len 610; since %len s< INT_MIN - (-5) from the entry condition 611 br i1 %iv.cmp, label %be, label %leave 612 613be: 614 call void @side_effect() 615 %be.cond = icmp slt i32 %iv.2, %len 616 br i1 %be.cond, label %loop, label %leave 617 618leave: 619 ret void 620} 621 622define i1 @func_18(i16* %tmp20, i32* %len.addr) { 623; CHECK-LABEL: @func_18( 624; CHECK-NEXT: entry: 625; CHECK-NEXT: [[LEN:%.*]] = load i32, i32* [[LEN_ADDR:%.*]], align 4, !range [[RNG0]] 626; CHECK-NEXT: [[TMP18:%.*]] = icmp eq i32 [[LEN]], 0 627; CHECK-NEXT: br i1 [[TMP18]], label [[BB2:%.*]], label [[BB0_PREHEADER:%.*]] 628; CHECK: bb0.preheader: 629; CHECK-NEXT: br label [[BB0:%.*]] 630; CHECK: bb0: 631; CHECK-NEXT: [[VAR_0_IN:%.*]] = phi i32 [ [[VAR_0:%.*]], [[BB1:%.*]] ], [ [[LEN]], [[BB0_PREHEADER]] ] 632; CHECK-NEXT: [[VAR_1:%.*]] = phi i32 [ [[TMP30:%.*]], [[BB1]] ], [ 0, [[BB0_PREHEADER]] ] 633; CHECK-NEXT: [[VAR_0]] = add nsw i32 [[VAR_0_IN]], -1 634; CHECK-NEXT: br i1 true, label [[STAY:%.*]], label [[BB2_LOOPEXIT:%.*]] 635; CHECK: stay: 636; CHECK-NEXT: [[TMP25:%.*]] = getelementptr inbounds i16, i16* [[TMP20:%.*]], i32 [[VAR_1]] 637; CHECK-NEXT: [[TMP26:%.*]] = load i16, i16* [[TMP25]], align 2 638; CHECK-NEXT: [[TMP29:%.*]] = icmp eq i16 [[TMP26]], 0 639; CHECK-NEXT: br i1 [[TMP29]], label [[BB1]], label [[BB2_LOOPEXIT]] 640; CHECK: bb1: 641; CHECK-NEXT: [[TMP30]] = add nuw i32 [[VAR_1]], 1 642; CHECK-NEXT: [[TMP31:%.*]] = icmp eq i32 [[VAR_0]], 0 643; CHECK-NEXT: br i1 [[TMP31]], label [[BB3:%.*]], label [[BB0]] 644; CHECK: bb2.loopexit: 645; CHECK-NEXT: br label [[BB2]] 646; CHECK: bb2: 647; CHECK-NEXT: ret i1 false 648; CHECK: bb3: 649; CHECK-NEXT: ret i1 true 650; 651entry: 652 %len = load i32, i32* %len.addr, !range !0 653 %tmp18 = icmp eq i32 %len, 0 654 br i1 %tmp18, label %bb2, label %bb0.preheader 655 656bb0.preheader: 657 br label %bb0 658 659bb0: 660 %var_0.in = phi i32 [ %var_0, %bb1 ], [ %len, %bb0.preheader ] 661 %var_1 = phi i32 [ %tmp30, %bb1 ], [ 0, %bb0.preheader ] 662 %var_0 = add nsw i32 %var_0.in, -1 663 %tmp23 = icmp ult i32 %var_1, %len 664 br i1 %tmp23, label %stay, label %bb2 665 666stay: 667 %tmp25 = getelementptr inbounds i16, i16* %tmp20, i32 %var_1 668 %tmp26 = load i16, i16* %tmp25 669 %tmp29 = icmp eq i16 %tmp26, 0 670 br i1 %tmp29, label %bb1, label %bb2 671 672bb1: 673 %tmp30 = add i32 %var_1, 1 674 %tmp31 = icmp eq i32 %var_0, 0 675 br i1 %tmp31, label %bb3, label %bb0 676 677bb2: 678 ret i1 false 679 680bb3: 681 ret i1 true 682} 683 684define void @func_19(i32* %length.ptr) { 685; CHECK-LABEL: @func_19( 686; CHECK-NEXT: entry: 687; CHECK-NEXT: [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4, !range [[RNG0]] 688; CHECK-NEXT: [[LENGTH_IS_NONZERO:%.*]] = icmp ne i32 [[LENGTH]], 0 689; CHECK-NEXT: br i1 [[LENGTH_IS_NONZERO]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]] 690; CHECK: loop.preheader: 691; CHECK-NEXT: br label [[LOOP:%.*]] 692; CHECK: loop: 693; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_INC:%.*]], [[BE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ] 694; CHECK-NEXT: [[IV_INC]] = add nuw nsw i32 [[IV]], 1 695; CHECK-NEXT: br i1 true, label [[BE]], label [[LEAVE_LOOPEXIT:%.*]] 696; CHECK: be: 697; CHECK-NEXT: call void @side_effect() 698; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV_INC]], [[LENGTH]] 699; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[LEAVE_LOOPEXIT]] 700; CHECK: leave.loopexit: 701; CHECK-NEXT: br label [[LEAVE]] 702; CHECK: leave: 703; CHECK-NEXT: ret void 704; 705entry: 706 %length = load i32, i32* %length.ptr, !range !0 707 %length.is.nonzero = icmp ne i32 %length, 0 708 br i1 %length.is.nonzero, label %loop, label %leave 709 710loop: 711 %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] 712 %iv.inc = add i32 %iv, 1 713 %range.check = icmp ult i32 %iv, %length 714 br i1 %range.check, label %be, label %leave 715 716be: 717 call void @side_effect() 718 %be.cond = icmp slt i32 %iv.inc, %length 719 br i1 %be.cond, label %loop, label %leave 720 721leave: 722 ret void 723} 724 725; Like @func_19, but %length is no longer provably positive, so 726; %range.check cannot be proved to be always true. 727define void @func_20(i32* %length.ptr) { 728; CHECK-LABEL: @func_20( 729; CHECK-NEXT: entry: 730; CHECK-NEXT: [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4 731; CHECK-NEXT: [[LENGTH_IS_NONZERO:%.*]] = icmp ne i32 [[LENGTH]], 0 732; CHECK-NEXT: br i1 [[LENGTH_IS_NONZERO]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]] 733; CHECK: loop.preheader: 734; CHECK-NEXT: [[SMAX:%.*]] = call i32 @llvm.smax.i32(i32 [[LENGTH]], i32 1) 735; CHECK-NEXT: br label [[LOOP:%.*]] 736; CHECK: loop: 737; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_INC:%.*]], [[BE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ] 738; CHECK-NEXT: [[IV_INC]] = add nuw nsw i32 [[IV]], 1 739; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV]], [[LENGTH]] 740; CHECK-NEXT: br i1 [[EXITCOND]], label [[BE]], label [[LEAVE_LOOPEXIT:%.*]] 741; CHECK: be: 742; CHECK-NEXT: call void @side_effect() 743; CHECK-NEXT: [[EXITCOND1:%.*]] = icmp ne i32 [[IV_INC]], [[SMAX]] 744; CHECK-NEXT: br i1 [[EXITCOND1]], label [[LOOP]], label [[LEAVE_LOOPEXIT]] 745; CHECK: leave.loopexit: 746; CHECK-NEXT: br label [[LEAVE]] 747; CHECK: leave: 748; CHECK-NEXT: ret void 749; 750entry: 751 %length = load i32, i32* %length.ptr 752 %length.is.nonzero = icmp ne i32 %length, 0 753 br i1 %length.is.nonzero, label %loop, label %leave 754 755loop: 756 %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] 757 %iv.inc = add i32 %iv, 1 758 %range.check = icmp ult i32 %iv, %length 759 br i1 %range.check, label %be, label %leave 760 761be: 762 call void @side_effect() 763 %be.cond = icmp slt i32 %iv.inc, %length 764 br i1 %be.cond, label %loop, label %leave 765 766leave: 767 ret void 768} 769 770; This checks that the backedge condition, (I + 1) < Length - 1 implies 771; (I + 1) < Length 772define void @func_21(i32* %length.ptr) { 773; CHECK-LABEL: @func_21( 774; CHECK-NEXT: entry: 775; CHECK-NEXT: [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4, !range [[RNG0]] 776; CHECK-NEXT: [[LIM:%.*]] = sub i32 [[LENGTH]], 1 777; CHECK-NEXT: [[ENTRY_COND:%.*]] = icmp sgt i32 [[LENGTH]], 1 778; CHECK-NEXT: br i1 [[ENTRY_COND]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]] 779; CHECK: loop.preheader: 780; CHECK-NEXT: br label [[LOOP:%.*]] 781; CHECK: loop: 782; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_INC:%.*]], [[BE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ] 783; CHECK-NEXT: [[IV_INC]] = add nuw nsw i32 [[IV]], 1 784; CHECK-NEXT: br i1 true, label [[BE]], label [[LEAVE_LOOPEXIT:%.*]] 785; CHECK: be: 786; CHECK-NEXT: call void @side_effect() 787; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV_INC]], [[LIM]] 788; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[LEAVE_LOOPEXIT]] 789; CHECK: leave.loopexit: 790; CHECK-NEXT: br label [[LEAVE]] 791; CHECK: leave: 792; CHECK-NEXT: ret void 793; 794entry: 795 %length = load i32, i32* %length.ptr, !range !0 796 %lim = sub i32 %length, 1 797 %entry.cond = icmp sgt i32 %length, 1 798 br i1 %entry.cond, label %loop, label %leave 799 800loop: 801 %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] 802 %iv.inc = add i32 %iv, 1 803 %range.check = icmp slt i32 %iv, %length 804 br i1 %range.check, label %be, label %leave 805 806be: 807 call void @side_effect() 808 %be.cond = icmp slt i32 %iv.inc, %lim 809 br i1 %be.cond, label %loop, label %leave 810 811leave: 812 ret void 813} 814 815; This checks that the backedge condition, (I + 1) < Length - 1 implies 816; (I + 1) < Length 817define void @func_22(i32* %length.ptr) { 818; CHECK-LABEL: @func_22( 819; CHECK-NEXT: entry: 820; CHECK-NEXT: [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4, !range [[RNG0]] 821; CHECK-NEXT: [[ENTRY_COND:%.*]] = icmp sgt i32 [[LENGTH]], 1 822; CHECK-NEXT: br i1 [[ENTRY_COND]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]] 823; CHECK: loop.preheader: 824; CHECK-NEXT: br label [[LOOP:%.*]] 825; CHECK: loop: 826; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_INC:%.*]], [[BE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ] 827; CHECK-NEXT: [[IV_INC]] = add nuw nsw i32 [[IV]], 1 828; CHECK-NEXT: br i1 true, label [[BE]], label [[LEAVE_LOOPEXIT:%.*]] 829; CHECK: be: 830; CHECK-NEXT: call void @side_effect() 831; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV_INC]], [[LENGTH]] 832; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[LEAVE_LOOPEXIT]] 833; CHECK: leave.loopexit: 834; CHECK-NEXT: br label [[LEAVE]] 835; CHECK: leave: 836; CHECK-NEXT: ret void 837; 838entry: 839 %length = load i32, i32* %length.ptr, !range !0 840 %lim = sub i32 %length, 1 841 %entry.cond = icmp sgt i32 %length, 1 842 br i1 %entry.cond, label %loop, label %leave 843 844loop: 845 %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] 846 %iv.inc = add i32 %iv, 1 847 %range.check = icmp sle i32 %iv, %length 848 br i1 %range.check, label %be, label %leave 849 850be: 851 call void @side_effect() 852 %be.cond = icmp sle i32 %iv.inc, %lim 853 br i1 %be.cond, label %loop, label %leave 854 855leave: 856 ret void 857} 858 859define void @func_23(i32* %length.ptr) { 860; CHECK-LABEL: @func_23( 861; CHECK-NEXT: entry: 862; CHECK-NEXT: [[LENGTH:%.*]] = load i32, i32* [[LENGTH_PTR:%.*]], align 4, !range [[RNG0]] 863; CHECK-NEXT: [[ENTRY_COND:%.*]] = icmp ult i32 4, [[LENGTH]] 864; CHECK-NEXT: br i1 [[ENTRY_COND]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]] 865; CHECK: loop.preheader: 866; CHECK-NEXT: br label [[LOOP:%.*]] 867; CHECK: loop: 868; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_INC:%.*]], [[BE:%.*]] ], [ 4, [[LOOP_PREHEADER]] ] 869; CHECK-NEXT: [[IV_INC]] = add nuw nsw i32 [[IV]], 1 870; CHECK-NEXT: br i1 true, label [[BE]], label [[LEAVE_LOOPEXIT:%.*]] 871; CHECK: be: 872; CHECK-NEXT: call void @side_effect() 873; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV_INC]], [[LENGTH]] 874; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[LEAVE_LOOPEXIT]] 875; CHECK: leave.loopexit: 876; CHECK-NEXT: br label [[LEAVE]] 877; CHECK: leave: 878; CHECK-NEXT: ret void 879; 880entry: 881 %length = load i32, i32* %length.ptr, !range !0 882 %entry.cond = icmp ult i32 4, %length 883 br i1 %entry.cond, label %loop, label %leave 884 885loop: 886 %iv = phi i32 [ 4, %entry ], [ %iv.inc, %be ] 887 %iv.inc = add i32 %iv, 1 888 %range.check = icmp slt i32 %iv, %length 889 br i1 %range.check, label %be, label %leave 890 891be: 892 call void @side_effect() 893 %be.cond = icmp slt i32 %iv.inc, %length 894 br i1 %be.cond, label %loop, label %leave 895 896leave: 897 ret void 898} 899 900define void @func_24(i32* %init.ptr) { 901; CHECK-LABEL: @func_24( 902; CHECK-NEXT: entry: 903; CHECK-NEXT: [[INIT:%.*]] = load i32, i32* [[INIT_PTR:%.*]], align 4, !range [[RNG0]] 904; CHECK-NEXT: [[ENTRY_COND:%.*]] = icmp ugt i32 [[INIT]], 4 905; CHECK-NEXT: br i1 [[ENTRY_COND]], label [[LOOP_PREHEADER:%.*]], label [[LEAVE:%.*]] 906; CHECK: loop.preheader: 907; CHECK-NEXT: br label [[LOOP:%.*]] 908; CHECK: loop: 909; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_DEC:%.*]], [[BE:%.*]] ], [ [[INIT]], [[LOOP_PREHEADER]] ] 910; CHECK-NEXT: [[IV_DEC]] = add nsw i32 [[IV]], -1 911; CHECK-NEXT: br i1 true, label [[BE]], label [[LEAVE_LOOPEXIT:%.*]] 912; CHECK: be: 913; CHECK-NEXT: call void @side_effect() 914; CHECK-NEXT: [[BE_COND:%.*]] = icmp sgt i32 [[IV_DEC]], 4 915; CHECK-NEXT: br i1 [[BE_COND]], label [[LOOP]], label [[LEAVE_LOOPEXIT]] 916; CHECK: leave.loopexit: 917; CHECK-NEXT: br label [[LEAVE]] 918; CHECK: leave: 919; CHECK-NEXT: ret void 920; 921entry: 922 %init = load i32, i32* %init.ptr, !range !0 923 %entry.cond = icmp ugt i32 %init, 4 924 br i1 %entry.cond, label %loop, label %leave 925 926loop: 927 %iv = phi i32 [ %init, %entry ], [ %iv.dec, %be ] 928 %iv.dec = add i32 %iv, -1 929 %range.check = icmp sgt i32 %iv, 4 930 br i1 %range.check, label %be, label %leave 931 932be: 933 call void @side_effect() 934 %be.cond = icmp sgt i32 %iv.dec, 4 935 br i1 %be.cond, label %loop, label %leave 936 937leave: 938 ret void 939} 940 941declare i1 @cond_func() 942 943define i32 @func_25(i32 %start) { 944; CHECK-LABEL: @func_25( 945; CHECK-NEXT: entry: 946; CHECK-NEXT: br label [[LOOP:%.*]] 947; CHECK: loop: 948; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ] 949; CHECK-NEXT: [[C1:%.*]] = icmp ne i32 [[IV]], 0 950; CHECK-NEXT: br i1 [[C1]], label [[CHECKED_1:%.*]], label [[FAIL:%.*]] 951; CHECK: checked.1: 952; CHECK-NEXT: br i1 true, label [[CHECKED_2:%.*]], label [[FAIL]] 953; CHECK: checked.2: 954; CHECK-NEXT: br i1 true, label [[BACKEDGE]], label [[FAIL]] 955; CHECK: backedge: 956; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 758394 957; CHECK-NEXT: [[LOOP_COND:%.*]] = call i1 @cond_func() 958; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]] 959; CHECK: fail: 960; CHECK-NEXT: unreachable 961; CHECK: exit: 962; CHECK-NEXT: [[IV_LCSSA1:%.*]] = phi i32 [ [[IV]], [[BACKEDGE]] ] 963; CHECK-NEXT: ret i32 [[IV_LCSSA1]] 964; 965entry: 966 br label %loop 967 968loop: 969 %iv = phi i32 [%start, %entry], [%iv.next, %backedge] 970 %c1 = icmp ne i32 %iv, 0 971 br i1 %c1, label %checked.1, label %fail 972 973checked.1: 974 %c2 = icmp ne i32 %iv, 0 975 br i1 %c2, label %checked.2, label %fail 976 977checked.2: 978 %c3 = icmp ne i32 %iv, 0 979 br i1 %c3, label %backedge, label %fail 980 981backedge: 982 %iv.next = add i32 %iv, 758394 983 %loop.cond = call i1 @cond_func() 984 br i1 %loop.cond, label %loop, label %exit 985 986fail: 987 unreachable 988 989exit: 990 ret i32 %iv 991} 992 993define i32 @func_26(i32 %start) { 994; CHECK-LABEL: @func_26( 995; CHECK-NEXT: entry: 996; CHECK-NEXT: br label [[LOOP:%.*]] 997; CHECK: loop: 998; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ] 999; CHECK-NEXT: [[C1:%.*]] = icmp slt i32 [[IV]], 0 1000; CHECK-NEXT: br i1 [[C1]], label [[CHECKED_1:%.*]], label [[FAIL:%.*]] 1001; CHECK: checked.1: 1002; CHECK-NEXT: br i1 true, label [[CHECKED_2:%.*]], label [[FAIL]] 1003; CHECK: checked.2: 1004; CHECK-NEXT: br i1 true, label [[BACKEDGE]], label [[FAIL]] 1005; CHECK: backedge: 1006; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 758394 1007; CHECK-NEXT: [[LOOP_COND:%.*]] = call i1 @cond_func() 1008; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]] 1009; CHECK: fail: 1010; CHECK-NEXT: unreachable 1011; CHECK: exit: 1012; CHECK-NEXT: [[IV_LCSSA1:%.*]] = phi i32 [ [[IV]], [[BACKEDGE]] ] 1013; CHECK-NEXT: ret i32 [[IV_LCSSA1]] 1014; 1015entry: 1016 br label %loop 1017 1018loop: 1019 %iv = phi i32 [%start, %entry], [%iv.next, %backedge] 1020 %c1 = icmp slt i32 %iv, 0 1021 br i1 %c1, label %checked.1, label %fail 1022 1023checked.1: 1024 %c2 = icmp slt i32 %iv, 1 1025 br i1 %c2, label %checked.2, label %fail 1026 1027checked.2: 1028 %c3 = icmp slt i32 %iv, 2 1029 br i1 %c3, label %backedge, label %fail 1030 1031backedge: 1032 %iv.next = add i32 %iv, 758394 1033 %loop.cond = call i1 @cond_func() 1034 br i1 %loop.cond, label %loop, label %exit 1035 1036fail: 1037 unreachable 1038 1039exit: 1040 ret i32 %iv 1041} 1042 1043define i32 @func_27(i32 %start) { 1044; CHECK-LABEL: @func_27( 1045; CHECK-NEXT: entry: 1046; CHECK-NEXT: br label [[LOOP:%.*]] 1047; CHECK: loop: 1048; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ] 1049; CHECK-NEXT: [[C1:%.*]] = icmp slt i32 [[IV]], 2 1050; CHECK-NEXT: [[C2:%.*]] = icmp slt i32 [[IV]], 1 1051; CHECK-NEXT: [[C3:%.*]] = icmp slt i32 [[IV]], 0 1052; CHECK-NEXT: br i1 [[C1]], label [[CHECKED_1:%.*]], label [[FAIL:%.*]] 1053; CHECK: checked.1: 1054; CHECK-NEXT: br i1 [[C2]], label [[CHECKED_2:%.*]], label [[FAIL]] 1055; CHECK: checked.2: 1056; CHECK-NEXT: br i1 [[C3]], label [[BACKEDGE]], label [[FAIL]] 1057; CHECK: backedge: 1058; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 758394 1059; CHECK-NEXT: [[LOOP_COND:%.*]] = call i1 @cond_func() 1060; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]] 1061; CHECK: fail: 1062; CHECK-NEXT: unreachable 1063; CHECK: exit: 1064; CHECK-NEXT: [[IV_LCSSA1:%.*]] = phi i32 [ [[IV]], [[BACKEDGE]] ] 1065; CHECK-NEXT: ret i32 [[IV_LCSSA1]] 1066; 1067entry: 1068 br label %loop 1069 1070loop: 1071 %iv = phi i32 [%start, %entry], [%iv.next, %backedge] 1072 %c1 = icmp slt i32 %iv, 2 1073 %c2 = icmp slt i32 %iv, 1 1074 %c3 = icmp slt i32 %iv, 0 1075 br i1 %c1, label %checked.1, label %fail 1076 1077checked.1: 1078 br i1 %c2, label %checked.2, label %fail 1079 1080checked.2: 1081 br i1 %c3, label %backedge, label %fail 1082 1083backedge: 1084 %iv.next = add i32 %iv, 758394 1085 %loop.cond = call i1 @cond_func() 1086 br i1 %loop.cond, label %loop, label %exit 1087 1088fail: 1089 unreachable 1090 1091exit: 1092 ret i32 %iv 1093} 1094 1095define i32 @func_28(i32 %start) { 1096; CHECK-LABEL: @func_28( 1097; CHECK-NEXT: entry: 1098; CHECK-NEXT: br label [[LOOP:%.*]] 1099; CHECK: loop: 1100; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ] 1101; CHECK-NEXT: [[C1:%.*]] = icmp ne i32 [[IV]], 0 1102; CHECK-NEXT: br i1 [[C1]], label [[CHECKED_1:%.*]], label [[FAIL:%.*]] 1103; CHECK: checked.1: 1104; CHECK-NEXT: br i1 true, label [[CHECKED_2:%.*]], label [[FAIL]] 1105; CHECK: checked.2: 1106; CHECK-NEXT: br i1 true, label [[BACKEDGE]], label [[FAIL]] 1107; CHECK: backedge: 1108; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 758394 1109; CHECK-NEXT: [[LOOP_COND:%.*]] = call i1 @cond_func() 1110; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]] 1111; CHECK: fail: 1112; CHECK-NEXT: unreachable 1113; CHECK: exit: 1114; CHECK-NEXT: [[IV_LCSSA1:%.*]] = phi i32 [ [[IV]], [[BACKEDGE]] ] 1115; CHECK-NEXT: ret i32 [[IV_LCSSA1]] 1116; 1117entry: 1118 br label %loop 1119 1120loop: 1121 %iv = phi i32 [%start, %entry], [%iv.next, %backedge] 1122 %c1 = icmp ne i32 %iv, 0 1123 %c2 = icmp ne i32 %iv, 0 1124 %c3 = icmp ne i32 %iv, 0 1125 br i1 %c1, label %checked.1, label %fail 1126 1127checked.1: 1128 br i1 %c2, label %checked.2, label %fail 1129 1130checked.2: 1131 br i1 %c3, label %backedge, label %fail 1132 1133backedge: 1134 %iv.next = add i32 %iv, 758394 1135 %loop.cond = call i1 @cond_func() 1136 br i1 %loop.cond, label %loop, label %exit 1137 1138fail: 1139 unreachable 1140 1141exit: 1142 ret i32 %iv 1143} 1144 1145!0 = !{i32 0, i32 2147483647} 1146