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1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py2; RUN: opt -S -passes=loop-vectorize -force-vector-width=4 -force-vector-interleave=1 < %s 2>&1 | FileCheck %s3 4target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"5 6; Check that the vectorizer identifies the %p.09 phi,7; as an induction variable, despite the potential overflow8; due to the truncation from 32bit to 8bit.9; SCEV will detect the pattern "sext(trunc(%p.09)) + %step"10; and generate the required runtime checks under which11; we can assume no overflow. We check here that we generate12; exactly two runtime checks:13; 1) an overflow check:14;    {0,+,(trunc i32 %step to i8)}<%for.body> Added Flags: <nssw>15; 2) an equality check verifying that the step of the induction16;    is equal to sext(trunc(step)):17;    Equal predicate: %step == (sext i8 (trunc i32 %step to i8) to i32)18;19; See also pr30654.20;21; int a[N];22; void doit1(int n, int step) {23;   int i;24;   char p = 0;25;   for (i = 0; i < n; i++) {26;      a[i] = p;27;      p = p + step;28;   }29; }30;31 32@a = common local_unnamed_addr global [250 x i32] zeroinitializer, align 1633 34; Function Attrs: norecurse nounwind uwtable35define void @doit1(i32 %n, i32 %step) local_unnamed_addr {36; CHECK-LABEL: @doit1(37; CHECK-NEXT:  entry:38; CHECK-NEXT:    [[CMP7:%.*]] = icmp sgt i32 [[N:%.*]], 039; CHECK-NEXT:    br i1 [[CMP7]], label [[FOR_BODY_PREHEADER:%.*]], label [[FOR_END:%.*]]40; CHECK:       for.body.preheader:41; CHECK-NEXT:    [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[N]] to i6442; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[WIDE_TRIP_COUNT]], 443; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label [[SCALAR_PH:%.*]], label [[VECTOR_SCEVCHECK:%.*]]44; CHECK:       vector.scevcheck:45; CHECK-NEXT:    [[TMP0:%.*]] = add nsw i64 [[WIDE_TRIP_COUNT]], -146; CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[STEP:%.*]] to i847; CHECK-NEXT:    [[TMP2:%.*]] = sub i8 0, [[TMP1]]48; CHECK-NEXT:    [[TMP3:%.*]] = icmp slt i8 [[TMP1]], 049; CHECK-NEXT:    [[TMP4:%.*]] = select i1 [[TMP3]], i8 [[TMP2]], i8 [[TMP1]]50; CHECK-NEXT:    [[TMP5:%.*]] = trunc i64 [[TMP0]] to i851; CHECK-NEXT:    [[MUL:%.*]] = call { i8, i1 } @llvm.umul.with.overflow.i8(i8 [[TMP4]], i8 [[TMP5]])52; CHECK-NEXT:    [[MUL_RESULT:%.*]] = extractvalue { i8, i1 } [[MUL]], 053; CHECK-NEXT:    [[MUL_OVERFLOW:%.*]] = extractvalue { i8, i1 } [[MUL]], 154; CHECK-NEXT:    [[TMP6:%.*]] = sub i8 0, [[MUL_RESULT]]55; CHECK-NEXT:    [[TMP7:%.*]] = icmp slt i8 [[MUL_RESULT]], 056; CHECK-NEXT:    [[TMP8:%.*]] = icmp sgt i8 [[TMP6]], 057; CHECK-NEXT:    [[TMP9:%.*]] = select i1 [[TMP3]], i1 [[TMP8]], i1 [[TMP7]]58; CHECK-NEXT:    [[TMP10:%.*]] = or i1 [[TMP9]], [[MUL_OVERFLOW]]59; CHECK-NEXT:    [[TMP11:%.*]] = icmp ugt i64 [[TMP0]], 25560; CHECK-NEXT:    [[TMP12:%.*]] = icmp ne i8 [[TMP1]], 061; CHECK-NEXT:    [[TMP13:%.*]] = and i1 [[TMP11]], [[TMP12]]62; CHECK-NEXT:    [[TMP14:%.*]] = or i1 [[TMP10]], [[TMP13]]63; CHECK-NEXT:    [[TMP15:%.*]] = sext i8 [[TMP1]] to i3264; CHECK-NEXT:    [[IDENT_CHECK:%.*]] = icmp ne i32 [[STEP]], [[TMP15]]65; CHECK-NEXT:    [[TMP16:%.*]] = or i1 [[TMP14]], [[IDENT_CHECK]]66; CHECK-NEXT:    br i1 [[TMP16]], label [[SCALAR_PH]], label [[VECTOR_PH:%.*]]67; CHECK:       vector.ph:68; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[WIDE_TRIP_COUNT]], 469; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[WIDE_TRIP_COUNT]], [[N_MOD_VF]]70; CHECK-NEXT:    [[DOTCAST:%.*]] = trunc i64 [[N_VEC]] to i3271; CHECK-NEXT:    [[IND_END:%.*]] = mul i32 [[DOTCAST]], [[STEP]]72; CHECK-NEXT:    [[DOTSPLATINSERT:%.*]] = insertelement <4 x i32> poison, i32 [[STEP]], i64 073; CHECK-NEXT:    [[DOTSPLAT:%.*]] = shufflevector <4 x i32> [[DOTSPLATINSERT]], <4 x i32> poison, <4 x i32> zeroinitializer74; CHECK-NEXT:    [[TMP19:%.*]] = mul nsw <4 x i32> <i32 0, i32 1, i32 2, i32 3>, [[DOTSPLAT]]75; CHECK-NEXT:    [[INDUCTION:%.*]] = add nsw <4 x i32> zeroinitializer, [[TMP19]]76; CHECK-NEXT:    [[TMP18:%.*]] = mul nsw i32 [[STEP]], 477; CHECK-NEXT:    [[DOTSPLATINSERT2:%.*]] = insertelement <4 x i32> poison, i32 [[TMP18]], i64 078; CHECK-NEXT:    [[DOTSPLAT3:%.*]] = shufflevector <4 x i32> [[DOTSPLATINSERT2]], <4 x i32> poison, <4 x i32> zeroinitializer79; CHECK-NEXT:    br label [[VECTOR_BODY:%.*]]80; CHECK:       vector.body:81; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]82; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i32> [ [[INDUCTION]], [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[VECTOR_BODY]] ]83; CHECK-NEXT:    [[TMP20:%.*]] = getelementptr inbounds [250 x i32], ptr @a, i64 0, i64 [[INDEX]]84; CHECK-NEXT:    store <4 x i32> [[VEC_IND]], ptr [[TMP20]], align 485; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 486; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nsw <4 x i32> [[VEC_IND]], [[DOTSPLAT3]]87; CHECK-NEXT:    [[TMP22:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]88; CHECK-NEXT:    br i1 [[TMP22]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]89; CHECK:       middle.block:90; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[WIDE_TRIP_COUNT]], [[N_VEC]]91; CHECK-NEXT:    br i1 [[CMP_N]], label [[FOR_END_LOOPEXIT:%.*]], label [[SCALAR_PH]]92; CHECK:       scalar.ph:93; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], [[MIDDLE_BLOCK]] ], [ 0, [[FOR_BODY_PREHEADER]] ], [ 0, [[VECTOR_SCEVCHECK]] ]94; CHECK-NEXT:    [[BC_RESUME_VAL1:%.*]] = phi i32 [ [[IND_END]], [[MIDDLE_BLOCK]] ], [ 0, [[FOR_BODY_PREHEADER]] ], [ 0, [[VECTOR_SCEVCHECK]] ]95; CHECK-NEXT:    br label [[FOR_BODY:%.*]]96; CHECK:       for.body:97; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], [[FOR_BODY]] ], [ [[BC_RESUME_VAL]], [[SCALAR_PH]] ]98; CHECK-NEXT:    [[P_09:%.*]] = phi i32 [ [[ADD:%.*]], [[FOR_BODY]] ], [ [[BC_RESUME_VAL1]], [[SCALAR_PH]] ]99; CHECK-NEXT:    [[SEXT:%.*]] = shl i32 [[P_09]], 24100; CHECK-NEXT:    [[CONV:%.*]] = ashr exact i32 [[SEXT]], 24101; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds [250 x i32], ptr @a, i64 0, i64 [[INDVARS_IV]]102; CHECK-NEXT:    store i32 [[CONV]], ptr [[ARRAYIDX]], align 4103; CHECK-NEXT:    [[ADD]] = add nsw i32 [[CONV]], [[STEP]]104; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1105; CHECK-NEXT:    [[EXITCOND:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], [[WIDE_TRIP_COUNT]]106; CHECK-NEXT:    br i1 [[EXITCOND]], label [[FOR_END_LOOPEXIT]], label [[FOR_BODY]], !llvm.loop [[LOOP3:![0-9]+]]107; CHECK:       for.end.loopexit:108; CHECK-NEXT:    br label [[FOR_END]]109; CHECK:       for.end:110; CHECK-NEXT:    ret void111;112entry:113  %cmp7 = icmp sgt i32 %n, 0114  br i1 %cmp7, label %for.body.preheader, label %for.end115 116for.body.preheader:117  %wide.trip.count = zext i32 %n to i64118  br label %for.body119 120for.body:121  %indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %for.body.preheader ]122  %p.09 = phi i32 [ %add, %for.body ], [ 0, %for.body.preheader ]123  %sext = shl i32 %p.09, 24124  %conv = ashr exact i32 %sext, 24125  %arrayidx = getelementptr inbounds [250 x i32], ptr @a, i64 0, i64 %indvars.iv126  store i32 %conv, ptr %arrayidx, align 4127  %add = add nsw i32 %conv, %step128  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1129  %exitcond = icmp eq i64 %indvars.iv.next, %wide.trip.count130  br i1 %exitcond, label %for.end.loopexit, label %for.body131 132for.end.loopexit:133  br label %for.end134 135for.end:136  ret void137}138 139; Same as above, but for checking the SCEV "zext(trunc(%p.09)) + %step".140; Here we expect the following two predicates to be added for runtime checking:141; 1) {0,+,(trunc i32 %step to i8)}<%for.body> Added Flags: <nusw>142; 2) Equal predicate: %step == (sext i8 (trunc i32 %step to i8) to i32)143;144; int a[N];145; void doit2(int n, int step) {146;   int i;147;   unsigned char p = 0;148;   for (i = 0; i < n; i++) {149;      a[i] = p;150;      p = p + step;151;   }152; }153;154 155 156; Function Attrs: norecurse nounwind uwtable157define void @doit2(i32 %n, i32 %step) local_unnamed_addr  {158; CHECK-LABEL: @doit2(159; CHECK-NEXT:  entry:160; CHECK-NEXT:    [[CMP7:%.*]] = icmp sgt i32 [[N:%.*]], 0161; CHECK-NEXT:    br i1 [[CMP7]], label [[FOR_BODY_PREHEADER:%.*]], label [[FOR_END:%.*]]162; CHECK:       for.body.preheader:163; CHECK-NEXT:    [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[N]] to i64164; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[WIDE_TRIP_COUNT]], 4165; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label [[SCALAR_PH:%.*]], label [[VECTOR_SCEVCHECK:%.*]]166; CHECK:       vector.scevcheck:167; CHECK-NEXT:    [[TMP0:%.*]] = add nsw i64 [[WIDE_TRIP_COUNT]], -1168; CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[STEP:%.*]] to i8169; CHECK-NEXT:    [[TMP2:%.*]] = sub i8 0, [[TMP1]]170; CHECK-NEXT:    [[TMP3:%.*]] = icmp slt i8 [[TMP1]], 0171; CHECK-NEXT:    [[TMP4:%.*]] = select i1 [[TMP3]], i8 [[TMP2]], i8 [[TMP1]]172; CHECK-NEXT:    [[TMP5:%.*]] = trunc i64 [[TMP0]] to i8173; CHECK-NEXT:    [[MUL:%.*]] = call { i8, i1 } @llvm.umul.with.overflow.i8(i8 [[TMP4]], i8 [[TMP5]])174; CHECK-NEXT:    [[MUL_RESULT:%.*]] = extractvalue { i8, i1 } [[MUL]], 0175; CHECK-NEXT:    [[MUL_OVERFLOW:%.*]] = extractvalue { i8, i1 } [[MUL]], 1176; CHECK-NEXT:    [[TMP6:%.*]] = sub i8 0, [[MUL_RESULT]]177; CHECK-NEXT:    [[TMP7:%.*]] = icmp ugt i8 [[TMP6]], 0178; CHECK-NEXT:    [[TMP8:%.*]] = select i1 [[TMP3]], i1 [[TMP7]], i1 false179; CHECK-NEXT:    [[TMP9:%.*]] = or i1 [[TMP8]], [[MUL_OVERFLOW]]180; CHECK-NEXT:    [[TMP10:%.*]] = icmp ugt i64 [[TMP0]], 255181; CHECK-NEXT:    [[TMP11:%.*]] = icmp ne i8 [[TMP1]], 0182; CHECK-NEXT:    [[TMP12:%.*]] = and i1 [[TMP10]], [[TMP11]]183; CHECK-NEXT:    [[TMP13:%.*]] = or i1 [[TMP9]], [[TMP12]]184; CHECK-NEXT:    [[TMP14:%.*]] = sext i8 [[TMP1]] to i32185; CHECK-NEXT:    [[IDENT_CHECK:%.*]] = icmp ne i32 [[STEP]], [[TMP14]]186; CHECK-NEXT:    [[TMP15:%.*]] = or i1 [[TMP13]], [[IDENT_CHECK]]187; CHECK-NEXT:    br i1 [[TMP15]], label [[SCALAR_PH]], label [[VECTOR_PH:%.*]]188; CHECK:       vector.ph:189; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[WIDE_TRIP_COUNT]], 4190; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[WIDE_TRIP_COUNT]], [[N_MOD_VF]]191; CHECK-NEXT:    [[DOTCAST:%.*]] = trunc i64 [[N_VEC]] to i32192; CHECK-NEXT:    [[IND_END:%.*]] = mul i32 [[DOTCAST]], [[STEP]]193; CHECK-NEXT:    [[DOTSPLATINSERT:%.*]] = insertelement <4 x i32> poison, i32 [[STEP]], i64 0194; CHECK-NEXT:    [[DOTSPLAT:%.*]] = shufflevector <4 x i32> [[DOTSPLATINSERT]], <4 x i32> poison, <4 x i32> zeroinitializer195; CHECK-NEXT:    [[TMP18:%.*]] = mul nsw <4 x i32> <i32 0, i32 1, i32 2, i32 3>, [[DOTSPLAT]]196; CHECK-NEXT:    [[INDUCTION:%.*]] = add nsw <4 x i32> zeroinitializer, [[TMP18]]197; CHECK-NEXT:    [[TMP17:%.*]] = mul nsw i32 [[STEP]], 4198; CHECK-NEXT:    [[DOTSPLATINSERT2:%.*]] = insertelement <4 x i32> poison, i32 [[TMP17]], i64 0199; CHECK-NEXT:    [[DOTSPLAT3:%.*]] = shufflevector <4 x i32> [[DOTSPLATINSERT2]], <4 x i32> poison, <4 x i32> zeroinitializer200; CHECK-NEXT:    br label [[VECTOR_BODY:%.*]]201; CHECK:       vector.body:202; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]203; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i32> [ [[INDUCTION]], [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[VECTOR_BODY]] ]204; CHECK-NEXT:    [[TMP19:%.*]] = getelementptr inbounds [250 x i32], ptr @a, i64 0, i64 [[INDEX]]205; CHECK-NEXT:    store <4 x i32> [[VEC_IND]], ptr [[TMP19]], align 4206; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 4207; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nsw <4 x i32> [[VEC_IND]], [[DOTSPLAT3]]208; CHECK-NEXT:    [[TMP21:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]209; CHECK-NEXT:    br i1 [[TMP21]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]210; CHECK:       middle.block:211; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[WIDE_TRIP_COUNT]], [[N_VEC]]212; CHECK-NEXT:    br i1 [[CMP_N]], label [[FOR_END_LOOPEXIT:%.*]], label [[SCALAR_PH]]213; CHECK:       scalar.ph:214; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], [[MIDDLE_BLOCK]] ], [ 0, [[FOR_BODY_PREHEADER]] ], [ 0, [[VECTOR_SCEVCHECK]] ]215; CHECK-NEXT:    [[BC_RESUME_VAL1:%.*]] = phi i32 [ [[IND_END]], [[MIDDLE_BLOCK]] ], [ 0, [[FOR_BODY_PREHEADER]] ], [ 0, [[VECTOR_SCEVCHECK]] ]216; CHECK-NEXT:    br label [[FOR_BODY:%.*]]217; CHECK:       for.body:218; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], [[FOR_BODY]] ], [ [[BC_RESUME_VAL]], [[SCALAR_PH]] ]219; CHECK-NEXT:    [[P_09:%.*]] = phi i32 [ [[ADD:%.*]], [[FOR_BODY]] ], [ [[BC_RESUME_VAL1]], [[SCALAR_PH]] ]220; CHECK-NEXT:    [[CONV:%.*]] = and i32 [[P_09]], 255221; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds [250 x i32], ptr @a, i64 0, i64 [[INDVARS_IV]]222; CHECK-NEXT:    store i32 [[CONV]], ptr [[ARRAYIDX]], align 4223; CHECK-NEXT:    [[ADD]] = add nsw i32 [[CONV]], [[STEP]]224; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1225; CHECK-NEXT:    [[EXITCOND:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], [[WIDE_TRIP_COUNT]]226; CHECK-NEXT:    br i1 [[EXITCOND]], label [[FOR_END_LOOPEXIT]], label [[FOR_BODY]], !llvm.loop [[LOOP5:![0-9]+]]227; CHECK:       for.end.loopexit:228; CHECK-NEXT:    br label [[FOR_END]]229; CHECK:       for.end:230; CHECK-NEXT:    ret void231;232entry:233  %cmp7 = icmp sgt i32 %n, 0234  br i1 %cmp7, label %for.body.preheader, label %for.end235 236for.body.preheader:237  %wide.trip.count = zext i32 %n to i64238  br label %for.body239 240for.body:241  %indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %for.body.preheader ]242  %p.09 = phi i32 [ %add, %for.body ], [ 0, %for.body.preheader ]243  %conv = and i32 %p.09, 255244  %arrayidx = getelementptr inbounds [250 x i32], ptr @a, i64 0, i64 %indvars.iv245  store i32 %conv, ptr %arrayidx, align 4246  %add = add nsw i32 %conv, %step247  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1248  %exitcond = icmp eq i64 %indvars.iv.next, %wide.trip.count249  br i1 %exitcond, label %for.end.loopexit, label %for.body250 251for.end.loopexit:252  br label %for.end253 254for.end:255  ret void256}257 258; Here we check that the same phi scev analysis would fail259; to create the runtime checks because the step is not invariant.260; As a result vectorization will fail.261;262; int a[N];263; void doit3(int n, int step) {264;   int i;265;   char p = 0;266;   for (i = 0; i < n; i++) {267;      a[i] = p;268;      p = p + step;269;      step += 2;270;   }271; }272;273 274 275; Function Attrs: norecurse nounwind uwtable276define void @doit3(i32 %n, i32 %step) local_unnamed_addr {277; CHECK-LABEL: @doit3(278; CHECK-NEXT:  entry:279; CHECK-NEXT:    [[CMP9:%.*]] = icmp sgt i32 [[N:%.*]], 0280; CHECK-NEXT:    br i1 [[CMP9]], label [[FOR_BODY_PREHEADER:%.*]], label [[FOR_END:%.*]]281; CHECK:       for.body.preheader:282; CHECK-NEXT:    [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[N]] to i64283; CHECK-NEXT:    br label [[FOR_BODY:%.*]]284; CHECK:       for.body:285; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], [[FOR_BODY]] ], [ 0, [[FOR_BODY_PREHEADER]] ]286; CHECK-NEXT:    [[P_012:%.*]] = phi i32 [ [[ADD:%.*]], [[FOR_BODY]] ], [ 0, [[FOR_BODY_PREHEADER]] ]287; CHECK-NEXT:    [[STEP_ADDR_010:%.*]] = phi i32 [ [[ADD3:%.*]], [[FOR_BODY]] ], [ [[STEP:%.*]], [[FOR_BODY_PREHEADER]] ]288; CHECK-NEXT:    [[SEXT:%.*]] = shl i32 [[P_012]], 24289; CHECK-NEXT:    [[CONV:%.*]] = ashr exact i32 [[SEXT]], 24290; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds [250 x i32], ptr @a, i64 0, i64 [[INDVARS_IV]]291; CHECK-NEXT:    store i32 [[CONV]], ptr [[ARRAYIDX]], align 4292; CHECK-NEXT:    [[ADD]] = add nsw i32 [[CONV]], [[STEP_ADDR_010]]293; CHECK-NEXT:    [[ADD3]] = add nsw i32 [[STEP_ADDR_010]], 2294; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1295; CHECK-NEXT:    [[EXITCOND:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], [[WIDE_TRIP_COUNT]]296; CHECK-NEXT:    br i1 [[EXITCOND]], label [[FOR_END_LOOPEXIT:%.*]], label [[FOR_BODY]]297; CHECK:       for.end.loopexit:298; CHECK-NEXT:    br label [[FOR_END]]299; CHECK:       for.end:300; CHECK-NEXT:    ret void301;302entry:303  %cmp9 = icmp sgt i32 %n, 0304  br i1 %cmp9, label %for.body.preheader, label %for.end305 306for.body.preheader:307  %wide.trip.count = zext i32 %n to i64308  br label %for.body309 310for.body:311  %indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %for.body.preheader ]312  %p.012 = phi i32 [ %add, %for.body ], [ 0, %for.body.preheader ]313  %step.addr.010 = phi i32 [ %add3, %for.body ], [ %step, %for.body.preheader ]314  %sext = shl i32 %p.012, 24315  %conv = ashr exact i32 %sext, 24316  %arrayidx = getelementptr inbounds [250 x i32], ptr @a, i64 0, i64 %indvars.iv317  store i32 %conv, ptr %arrayidx, align 4318  %add = add nsw i32 %conv, %step.addr.010319  %add3 = add nsw i32 %step.addr.010, 2320  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1321  %exitcond = icmp eq i64 %indvars.iv.next, %wide.trip.count322  br i1 %exitcond, label %for.end.loopexit, label %for.body323 324for.end.loopexit:325  br label %for.end326 327for.end:328  ret void329}330 331 332; Lastly, we also check the case where we can tell at compile time that333; the step of the induction is equal to sext(trunc(step)), in which case334; we don't have to check this equality at runtime (we only need the335; runtime overflow check). Therefore only the following overflow predicate336; will be added for runtime checking:337; {0,+,%cstep}<%for.body> Added Flags: <nssw>338;339; a[N];340; void doit4(int n, char cstep) {341;   int i;342;   char p = 0;343;   int istep = cstep;344;  for (i = 0; i < n; i++) {345;      a[i] = p;346;      p = p + istep;347;   }348; }349 350 351; Function Attrs: norecurse nounwind uwtable352define void @doit4(i32 %n, i8 signext %cstep) local_unnamed_addr {353; CHECK-LABEL: @doit4(354; CHECK-NEXT:  entry:355; CHECK-NEXT:    [[CONV:%.*]] = sext i8 [[CSTEP:%.*]] to i32356; CHECK-NEXT:    [[CMP10:%.*]] = icmp sgt i32 [[N:%.*]], 0357; CHECK-NEXT:    br i1 [[CMP10]], label [[FOR_BODY_PREHEADER:%.*]], label [[FOR_END:%.*]]358; CHECK:       for.body.preheader:359; CHECK-NEXT:    [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[N]] to i64360; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[WIDE_TRIP_COUNT]], 4361; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label [[SCALAR_PH:%.*]], label [[VECTOR_SCEVCHECK:%.*]]362; CHECK:       vector.scevcheck:363; CHECK-NEXT:    [[TMP0:%.*]] = add nsw i64 [[WIDE_TRIP_COUNT]], -1364; CHECK-NEXT:    [[TMP1:%.*]] = sub i8 0, [[CSTEP]]365; CHECK-NEXT:    [[TMP2:%.*]] = icmp slt i8 [[CSTEP]], 0366; CHECK-NEXT:    [[TMP3:%.*]] = select i1 [[TMP2]], i8 [[TMP1]], i8 [[CSTEP]]367; CHECK-NEXT:    [[TMP4:%.*]] = trunc i64 [[TMP0]] to i8368; CHECK-NEXT:    [[MUL:%.*]] = call { i8, i1 } @llvm.umul.with.overflow.i8(i8 [[TMP3]], i8 [[TMP4]])369; CHECK-NEXT:    [[MUL_RESULT:%.*]] = extractvalue { i8, i1 } [[MUL]], 0370; CHECK-NEXT:    [[MUL_OVERFLOW:%.*]] = extractvalue { i8, i1 } [[MUL]], 1371; CHECK-NEXT:    [[TMP5:%.*]] = sub i8 0, [[MUL_RESULT]]372; CHECK-NEXT:    [[TMP6:%.*]] = icmp slt i8 [[MUL_RESULT]], 0373; CHECK-NEXT:    [[TMP7:%.*]] = icmp sgt i8 [[TMP5]], 0374; CHECK-NEXT:    [[TMP8:%.*]] = select i1 [[TMP2]], i1 [[TMP7]], i1 [[TMP6]]375; CHECK-NEXT:    [[TMP9:%.*]] = or i1 [[TMP8]], [[MUL_OVERFLOW]]376; CHECK-NEXT:    [[TMP10:%.*]] = icmp ugt i64 [[TMP0]], 255377; CHECK-NEXT:    [[TMP11:%.*]] = icmp ne i8 [[CSTEP]], 0378; CHECK-NEXT:    [[TMP12:%.*]] = and i1 [[TMP10]], [[TMP11]]379; CHECK-NEXT:    [[TMP13:%.*]] = or i1 [[TMP9]], [[TMP12]]380; CHECK-NEXT:    br i1 [[TMP13]], label [[SCALAR_PH]], label [[VECTOR_PH:%.*]]381; CHECK:       vector.ph:382; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[WIDE_TRIP_COUNT]], 4383; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[WIDE_TRIP_COUNT]], [[N_MOD_VF]]384; CHECK-NEXT:    [[DOTCAST:%.*]] = trunc i64 [[N_VEC]] to i32385; CHECK-NEXT:    [[IND_END:%.*]] = mul i32 [[DOTCAST]], [[CONV]]386; CHECK-NEXT:    [[DOTSPLATINSERT:%.*]] = insertelement <4 x i32> poison, i32 [[CONV]], i64 0387; CHECK-NEXT:    [[DOTSPLAT:%.*]] = shufflevector <4 x i32> [[DOTSPLATINSERT]], <4 x i32> poison, <4 x i32> zeroinitializer388; CHECK-NEXT:    [[TMP16:%.*]] = mul nsw <4 x i32> <i32 0, i32 1, i32 2, i32 3>, [[DOTSPLAT]]389; CHECK-NEXT:    [[INDUCTION:%.*]] = add nsw <4 x i32> zeroinitializer, [[TMP16]]390; CHECK-NEXT:    [[TMP15:%.*]] = mul nsw i32 [[CONV]], 4391; CHECK-NEXT:    [[DOTSPLATINSERT2:%.*]] = insertelement <4 x i32> poison, i32 [[TMP15]], i64 0392; CHECK-NEXT:    [[DOTSPLAT3:%.*]] = shufflevector <4 x i32> [[DOTSPLATINSERT2]], <4 x i32> poison, <4 x i32> zeroinitializer393; CHECK-NEXT:    br label [[VECTOR_BODY:%.*]]394; CHECK:       vector.body:395; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]396; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i32> [ [[INDUCTION]], [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[VECTOR_BODY]] ]397; CHECK-NEXT:    [[TMP17:%.*]] = getelementptr inbounds [250 x i32], ptr @a, i64 0, i64 [[INDEX]]398; CHECK-NEXT:    store <4 x i32> [[VEC_IND]], ptr [[TMP17]], align 4399; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 4400; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nsw <4 x i32> [[VEC_IND]], [[DOTSPLAT3]]401; CHECK-NEXT:    [[TMP19:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]402; CHECK-NEXT:    br i1 [[TMP19]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]403; CHECK:       middle.block:404; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[WIDE_TRIP_COUNT]], [[N_VEC]]405; CHECK-NEXT:    br i1 [[CMP_N]], label [[FOR_END_LOOPEXIT:%.*]], label [[SCALAR_PH]]406; CHECK:       scalar.ph:407; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], [[MIDDLE_BLOCK]] ], [ 0, [[FOR_BODY_PREHEADER]] ], [ 0, [[VECTOR_SCEVCHECK]] ]408; CHECK-NEXT:    [[BC_RESUME_VAL1:%.*]] = phi i32 [ [[IND_END]], [[MIDDLE_BLOCK]] ], [ 0, [[FOR_BODY_PREHEADER]] ], [ 0, [[VECTOR_SCEVCHECK]] ]409; CHECK-NEXT:    br label [[FOR_BODY:%.*]]410; CHECK:       for.body:411; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], [[FOR_BODY]] ], [ [[BC_RESUME_VAL]], [[SCALAR_PH]] ]412; CHECK-NEXT:    [[P_011:%.*]] = phi i32 [ [[ADD:%.*]], [[FOR_BODY]] ], [ [[BC_RESUME_VAL1]], [[SCALAR_PH]] ]413; CHECK-NEXT:    [[SEXT:%.*]] = shl i32 [[P_011]], 24414; CHECK-NEXT:    [[CONV2:%.*]] = ashr exact i32 [[SEXT]], 24415; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds [250 x i32], ptr @a, i64 0, i64 [[INDVARS_IV]]416; CHECK-NEXT:    store i32 [[CONV2]], ptr [[ARRAYIDX]], align 4417; CHECK-NEXT:    [[ADD]] = add nsw i32 [[CONV2]], [[CONV]]418; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1419; CHECK-NEXT:    [[EXITCOND:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], [[WIDE_TRIP_COUNT]]420; CHECK-NEXT:    br i1 [[EXITCOND]], label [[FOR_END_LOOPEXIT]], label [[FOR_BODY]], !llvm.loop [[LOOP7:![0-9]+]]421; CHECK:       for.end.loopexit:422; CHECK-NEXT:    br label [[FOR_END]]423; CHECK:       for.end:424; CHECK-NEXT:    ret void425;426entry:427  %conv = sext i8 %cstep to i32428  %cmp10 = icmp sgt i32 %n, 0429  br i1 %cmp10, label %for.body.preheader, label %for.end430 431for.body.preheader:432  %wide.trip.count = zext i32 %n to i64433  br label %for.body434 435for.body:436  %indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %for.body.preheader ]437  %p.011 = phi i32 [ %add, %for.body ], [ 0, %for.body.preheader ]438  %sext = shl i32 %p.011, 24439  %conv2 = ashr exact i32 %sext, 24440  %arrayidx = getelementptr inbounds [250 x i32], ptr @a, i64 0, i64 %indvars.iv441  store i32 %conv2, ptr %arrayidx, align 4442  %add = add nsw i32 %conv2, %conv443  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1444  %exitcond = icmp eq i64 %indvars.iv.next, %wide.trip.count445  br i1 %exitcond, label %for.end.loopexit, label %for.body446 447for.end.loopexit:448  br label %for.end449 450for.end:451  ret void452}453