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Revert "SCEV: teach isImpliedViaOperations about samesign" (#126506)

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The commit f5d24e6c is buggy, and following miscompiles have been
reported: #126409 and
https://github.com/llvm/llvm-project/pull/124270#issuecomment-2647222903

Revert it while we investigate.
This commit is contained in:
Ramkumar Ramachandra 2025-02-10 13:31:18 +00:00 committed by GitHub
parent af2a228e0b
commit c6b13a2871
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GPG Key ID: B5690EEEBB952194
4 changed files with 59 additions and 166 deletions
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33
llvm/lib/Analysis/ScalarEvolution.cpp
View File

@ -11860,13 +11860,15 @@ bool ScalarEvolution::isImpliedCondBalancedTypes(
}
// Check whether the found predicate is the same as the desired predicate.
if (auto P = CmpPredicate::getMatching(FoundPred, Pred))
return isImpliedCondOperands(*P, LHS, RHS, FoundLHS, FoundRHS, CtxI);
// FIXME: use CmpPredicate::getMatching here.
if (FoundPred == static_cast<CmpInst::Predicate>(Pred))
return isImpliedCondOperands(Pred, LHS, RHS, FoundLHS, FoundRHS, CtxI);
// Check whether swapping the found predicate makes it the same as the
// desired predicate.
if (auto P = CmpPredicate::getMatching(
ICmpInst::getSwappedCmpPredicate(FoundPred), Pred)) {
// FIXME: use CmpPredicate::getMatching here.
if (ICmpInst::getSwappedCmpPredicate(FoundPred) ==
static_cast<CmpInst::Predicate>(Pred)) {
// We can write the implication
// 0. LHS Pred RHS <- FoundLHS SwapPred FoundRHS
// using one of the following ways:
@ -11877,23 +11879,22 @@ bool ScalarEvolution::isImpliedCondBalancedTypes(
// Forms 1. and 2. require swapping the operands of one condition. Don't
// do this if it would break canonical constant/addrec ordering.
if (!isa<SCEVConstant>(RHS) && !isa<SCEVAddRecExpr>(LHS))
return isImpliedCondOperands(ICmpInst::getSwappedCmpPredicate(*P), RHS,
LHS, FoundLHS, FoundRHS, CtxI);
return isImpliedCondOperands(FoundPred, RHS, LHS, FoundLHS, FoundRHS,
CtxI);
if (!isa<SCEVConstant>(FoundRHS) && !isa<SCEVAddRecExpr>(FoundLHS))
return isImpliedCondOperands(*P, LHS, RHS, FoundRHS, FoundLHS, CtxI);
return isImpliedCondOperands(Pred, LHS, RHS, FoundRHS, FoundLHS, CtxI);
// There's no clear preference between forms 3. and 4., try both. Avoid
// forming getNotSCEV of pointer values as the resulting subtract is
// not legal.
if (!LHS->getType()->isPointerTy() && !RHS->getType()->isPointerTy() &&
isImpliedCondOperands(ICmpInst::getSwappedCmpPredicate(*P),
getNotSCEV(LHS), getNotSCEV(RHS), FoundLHS,
FoundRHS, CtxI))
isImpliedCondOperands(FoundPred, getNotSCEV(LHS), getNotSCEV(RHS),
FoundLHS, FoundRHS, CtxI))
return true;
if (!FoundLHS->getType()->isPointerTy() &&
!FoundRHS->getType()->isPointerTy() &&
isImpliedCondOperands(*P, LHS, RHS, getNotSCEV(FoundLHS),
isImpliedCondOperands(Pred, LHS, RHS, getNotSCEV(FoundLHS),
getNotSCEV(FoundRHS), CtxI))
return true;
@ -12569,16 +12570,14 @@ bool ScalarEvolution::isImpliedViaOperations(CmpPredicate Pred, const SCEV *LHS,
return false;
// We only want to work with GT comparison so far.
if (ICmpInst::isLT(Pred)) {
if (Pred == ICmpInst::ICMP_ULT || Pred == ICmpInst::ICMP_SLT) {
Pred = ICmpInst::getSwappedCmpPredicate(Pred);
std::swap(LHS, RHS);
std::swap(FoundLHS, FoundRHS);
}
CmpInst::Predicate P = Pred.getPreferredSignedPredicate();
// For unsigned, try to reduce it to corresponding signed comparison.
if (P == ICmpInst::ICMP_UGT)
if (Pred == ICmpInst::ICMP_UGT)
// We can replace unsigned predicate with its signed counterpart if all
// involved values are non-negative.
// TODO: We could have better support for unsigned.
@ -12591,10 +12590,10 @@ bool ScalarEvolution::isImpliedViaOperations(CmpPredicate Pred, const SCEV *LHS,
FoundRHS) &&
isImpliedCondOperands(ICmpInst::ICMP_SGT, RHS, MinusOne, FoundLHS,
FoundRHS))
P = ICmpInst::ICMP_SGT;
Pred = ICmpInst::ICMP_SGT;
}
if (P != ICmpInst::ICMP_SGT)
if (Pred != ICmpInst::ICMP_SGT)
return false;
auto GetOpFromSExt = [&](const SCEV *S) {

4
llvm/test/Analysis/ScalarEvolution/exit-count-samesign.ll
View File

@ -5,9 +5,9 @@
define i32 @exit_count_samesign(i32 %iter.count, ptr %ptr) {
; CHECK-LABEL: 'exit_count_samesign'
; CHECK-NEXT: Determining loop execution counts for: @exit_count_samesign
; CHECK-NEXT: Loop %inner.loop: backedge-taken count is {(-2 + %iter.count),+,-1}<nw><%outer.loop>
; CHECK-NEXT: Loop %inner.loop: backedge-taken count is (-1 + (1 smax {(-1 + %iter.count)<nsw>,+,-1}<nsw><%outer.loop>))<nsw>
; CHECK-NEXT: Loop %inner.loop: constant max backedge-taken count is i32 2147483646
; CHECK-NEXT: Loop %inner.loop: symbolic max backedge-taken count is {(-2 + %iter.count),+,-1}<nw><%outer.loop>
; CHECK-NEXT: Loop %inner.loop: symbolic max backedge-taken count is (-1 + (1 smax {(-1 + %iter.count)<nsw>,+,-1}<nsw><%outer.loop>))<nsw>
; CHECK-NEXT: Loop %inner.loop: Trip multiple is 1
; CHECK-NEXT: Loop %outer.loop: <multiple exits> Unpredictable backedge-taken count.
; CHECK-NEXT: Loop %outer.loop: Unpredictable constant max backedge-taken count.

164
llvm/test/Analysis/ScalarEvolution/implied-via-division.ll
View File

@ -2,10 +2,12 @@
; RUN: opt < %s -disable-output -passes="print<scalar-evolution>" \
; RUN: -scalar-evolution-classify-expressions=0 2>&1 | FileCheck %s
define void @implied1(i32 %n) {
; Prove that (n s> 1) ===> (n / 2 s> 0).
; CHECK-LABEL: 'implied1'
; CHECK-NEXT: Determining loop execution counts for: @implied1
declare void @llvm.experimental.guard(i1, ...)
define void @test_1(i32 %n) nounwind {
; Prove that (n > 1) ===> (n / 2 > 0).
; CHECK-LABEL: 'test_1'
; CHECK-NEXT: Determining loop execution counts for: @test_1
; CHECK-NEXT: Loop %header: backedge-taken count is (-1 + %n.div.2)<nsw>
; CHECK-NEXT: Loop %header: constant max backedge-taken count is i32 1073741822
; CHECK-NEXT: Loop %header: symbolic max backedge-taken count is (-1 + %n.div.2)<nsw>
@ -27,35 +29,10 @@ exit:
ret void
}
define void @implied1_samesign(i32 %n) {
; Prove that (n > 1) ===> (n / 2 s> 0).
; CHECK-LABEL: 'implied1_samesign'
; CHECK-NEXT: Determining loop execution counts for: @implied1_samesign
; CHECK-NEXT: Loop %header: backedge-taken count is (-1 + %n.div.2)<nsw>
; CHECK-NEXT: Loop %header: constant max backedge-taken count is i32 1073741822
; CHECK-NEXT: Loop %header: symbolic max backedge-taken count is (-1 + %n.div.2)<nsw>
; CHECK-NEXT: Loop %header: Trip multiple is 1
;
entry:
%cmp1 = icmp samesign ugt i32 %n, 1
%n.div.2 = sdiv i32 %n, 2
call void @llvm.assume(i1 %cmp1)
br label %header
header:
%indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
%indvar.next = add i32 %indvar, 1
%exitcond = icmp sgt i32 %n.div.2, %indvar.next
br i1 %exitcond, label %header, label %exit
exit:
ret void
}
define void @implied1_neg(i32 %n) {
; Prove that (n s> 0) =\=> (n / 2 s> 0).
; CHECK-LABEL: 'implied1_neg'
; CHECK-NEXT: Determining loop execution counts for: @implied1_neg
define void @test_1neg(i32 %n) nounwind {
; Prove that (n > 0) =\=> (n / 2 > 0).
; CHECK-LABEL: 'test_1neg'
; CHECK-NEXT: Determining loop execution counts for: @test_1neg
; CHECK-NEXT: Loop %header: backedge-taken count is (-1 + (1 smax %n.div.2))<nsw>
; CHECK-NEXT: Loop %header: constant max backedge-taken count is i32 1073741822
; CHECK-NEXT: Loop %header: symbolic max backedge-taken count is (-1 + (1 smax %n.div.2))<nsw>
@ -77,10 +54,10 @@ exit:
ret void
}
define void @implied2(i32 %n) {
; Prove that (n s>= 2) ===> (n / 2 s> 0).
; CHECK-LABEL: 'implied2'
; CHECK-NEXT: Determining loop execution counts for: @implied2
define void @test_2(i32 %n) nounwind {
; Prove that (n >= 2) ===> (n / 2 > 0).
; CHECK-LABEL: 'test_2'
; CHECK-NEXT: Determining loop execution counts for: @test_2
; CHECK-NEXT: Loop %header: backedge-taken count is (-1 + %n.div.2)<nsw>
; CHECK-NEXT: Loop %header: constant max backedge-taken count is i32 1073741822
; CHECK-NEXT: Loop %header: symbolic max backedge-taken count is (-1 + %n.div.2)<nsw>
@ -102,35 +79,10 @@ exit:
ret void
}
define void @implied2_samesign(i32 %n) {
; Prove that (n >= 2) ===> (n / 2 s> 0).
; CHECK-LABEL: 'implied2_samesign'
; CHECK-NEXT: Determining loop execution counts for: @implied2_samesign
; CHECK-NEXT: Loop %header: backedge-taken count is (-1 + (1 smax %n.div.2))<nsw>
; CHECK-NEXT: Loop %header: constant max backedge-taken count is i32 1073741822
; CHECK-NEXT: Loop %header: symbolic max backedge-taken count is (-1 + (1 smax %n.div.2))<nsw>
; CHECK-NEXT: Loop %header: Trip multiple is 1
;
entry:
%cmp1 = icmp samesign uge i32 %n, 2
%n.div.2 = sdiv i32 %n, 2
call void @llvm.assume(i1 %cmp1)
br label %header
header:
%indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
%indvar.next = add i32 %indvar, 1
%exitcond = icmp sgt i32 %n.div.2, %indvar.next
br i1 %exitcond, label %header, label %exit
exit:
ret void
}
define void @implied2_neg(i32 %n) {
; Prove that (n s>= 1) =\=> (n / 2 s> 0).
; CHECK-LABEL: 'implied2_neg'
; CHECK-NEXT: Determining loop execution counts for: @implied2_neg
define void @test_2neg(i32 %n) nounwind {
; Prove that (n >= 1) =\=> (n / 2 > 0).
; CHECK-LABEL: 'test_2neg'
; CHECK-NEXT: Determining loop execution counts for: @test_2neg
; CHECK-NEXT: Loop %header: backedge-taken count is (-1 + (1 smax %n.div.2))<nsw>
; CHECK-NEXT: Loop %header: constant max backedge-taken count is i32 1073741822
; CHECK-NEXT: Loop %header: symbolic max backedge-taken count is (-1 + (1 smax %n.div.2))<nsw>
@ -152,10 +104,10 @@ exit:
ret void
}
define void @implied3(i32 %n) {
; Prove that (n s> -2) ===> (n / 2 s>= 0).
; CHECK-LABEL: 'implied3'
; CHECK-NEXT: Determining loop execution counts for: @implied3
define void @test_3(i32 %n) nounwind {
; Prove that (n > -2) ===> (n / 2 >= 0).
; CHECK-LABEL: 'test_3'
; CHECK-NEXT: Determining loop execution counts for: @test_3
; CHECK-NEXT: Loop %header: backedge-taken count is (1 + %n.div.2)<nsw>
; CHECK-NEXT: Loop %header: constant max backedge-taken count is i32 1073741824
; CHECK-NEXT: Loop %header: symbolic max backedge-taken count is (1 + %n.div.2)<nsw>
@ -177,35 +129,10 @@ exit:
ret void
}
define void @implied3_samesign(i32 %n) {
; Prove that (n > -2) ===> (n / 2 s>= 0).
; CHECK-LABEL: 'implied3_samesign'
; CHECK-NEXT: Determining loop execution counts for: @implied3_samesign
; CHECK-NEXT: Loop %header: backedge-taken count is (1 + %n.div.2)<nsw>
; CHECK-NEXT: Loop %header: constant max backedge-taken count is i32 1
; CHECK-NEXT: Loop %header: symbolic max backedge-taken count is (1 + %n.div.2)<nsw>
; CHECK-NEXT: Loop %header: Trip multiple is 1
;
entry:
%cmp1 = icmp samesign ugt i32 %n, -2
%n.div.2 = sdiv i32 %n, 2
call void @llvm.assume(i1 %cmp1)
br label %header
header:
%indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
%indvar.next = add i32 %indvar, 1
%exitcond = icmp sge i32 %n.div.2, %indvar
br i1 %exitcond, label %header, label %exit
exit:
ret void
}
define void @implied3_neg(i32 %n) {
define void @test_3neg(i32 %n) nounwind {
; Prove that (n > -3) =\=> (n / 2 >= 0).
; CHECK-LABEL: 'implied3_neg'
; CHECK-NEXT: Determining loop execution counts for: @implied3_neg
; CHECK-LABEL: 'test_3neg'
; CHECK-NEXT: Determining loop execution counts for: @test_3neg
; CHECK-NEXT: Loop %header: backedge-taken count is (0 smax (1 + %n.div.2)<nsw>)
; CHECK-NEXT: Loop %header: constant max backedge-taken count is i32 1073741824
; CHECK-NEXT: Loop %header: symbolic max backedge-taken count is (0 smax (1 + %n.div.2)<nsw>)
@ -227,10 +154,10 @@ exit:
ret void
}
define void @implied4(i32 %n) {
; Prove that (n s>= -1) ===> (n / 2 s>= 0).
; CHECK-LABEL: 'implied4'
; CHECK-NEXT: Determining loop execution counts for: @implied4
define void @test_4(i32 %n) nounwind {
; Prove that (n >= -1) ===> (n / 2 >= 0).
; CHECK-LABEL: 'test_4'
; CHECK-NEXT: Determining loop execution counts for: @test_4
; CHECK-NEXT: Loop %header: backedge-taken count is (1 + %n.div.2)<nsw>
; CHECK-NEXT: Loop %header: constant max backedge-taken count is i32 1073741824
; CHECK-NEXT: Loop %header: symbolic max backedge-taken count is (1 + %n.div.2)<nsw>
@ -252,35 +179,10 @@ exit:
ret void
}
define void @implied4_samesign(i32 %n) {
; Prove that (n >= -1) ===> (n / 2 s>= 0).
; CHECK-LABEL: 'implied4_samesign'
; CHECK-NEXT: Determining loop execution counts for: @implied4_samesign
; CHECK-NEXT: Loop %header: backedge-taken count is (1 + %n.div.2)<nsw>
; CHECK-NEXT: Loop %header: constant max backedge-taken count is i32 1
; CHECK-NEXT: Loop %header: symbolic max backedge-taken count is (1 + %n.div.2)<nsw>
; CHECK-NEXT: Loop %header: Trip multiple is 1
;
entry:
%cmp1 = icmp samesign uge i32 %n, -1
%n.div.2 = sdiv i32 %n, 2
call void @llvm.assume(i1 %cmp1)
br label %header
header:
%indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
%indvar.next = add i32 %indvar, 1
%exitcond = icmp sge i32 %n.div.2, %indvar
br i1 %exitcond, label %header, label %exit
exit:
ret void
}
define void @implied4_neg(i32 %n) {
; Prove that (n s>= -2) =\=> (n / 2 s>= 0).
; CHECK-LABEL: 'implied4_neg'
; CHECK-NEXT: Determining loop execution counts for: @implied4_neg
define void @test_4neg(i32 %n) nounwind {
; Prove that (n >= -2) =\=> (n / 2 >= 0).
; CHECK-LABEL: 'test_4neg'
; CHECK-NEXT: Determining loop execution counts for: @test_4neg
; CHECK-NEXT: Loop %header: backedge-taken count is (0 smax (1 + %n.div.2)<nsw>)
; CHECK-NEXT: Loop %header: constant max backedge-taken count is i32 1073741824
; CHECK-NEXT: Loop %header: symbolic max backedge-taken count is (0 smax (1 + %n.div.2)<nsw>)

24
llvm/test/Transforms/IndVarSimplify/iv-ext-samesign.ll
View File

@ -68,32 +68,28 @@ define i32 @iv_zext_zext_gt_slt(i32 %iter.count, ptr %ptr) {
; CHECK-LABEL: define i32 @iv_zext_zext_gt_slt(
; CHECK-SAME: i32 [[ITER_COUNT:%.*]], ptr [[PTR:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: [[TMP0:%.*]] = add nsw i32 [[ITER_COUNT]], -1
; CHECK-NEXT: [[TMP0:%.*]] = sext i32 [[ITER_COUNT]] to i64
; CHECK-NEXT: br label %[[OUTER_LOOP:.*]]
; CHECK: [[PH_LOOPEXIT:.*]]:
; CHECK-NEXT: br label %[[PH:.*]]
; CHECK: [[PH]]:
; CHECK-NEXT: [[INDVARS_IV_NEXT3:%.*]] = add i32 [[INDVARS_IV1:%.*]], -1
; CHECK-NEXT: br label %[[OUTER_LOOP]]
; CHECK: [[OUTER_LOOP]]:
; CHECK-NEXT: [[INDVARS_IV1]] = phi i32 [ [[INDVARS_IV_NEXT3]], %[[PH]] ], [ [[TMP0]], %[[ENTRY]] ]
; CHECK-NEXT: [[IV_OUTER:%.*]] = phi i32 [ [[IV_OUTER_1:%.*]], %[[PH]] ], [ [[ITER_COUNT]], %[[ENTRY]] ]
; CHECK-NEXT: [[IV_OUTER_1]] = add nsw i32 [[IV_OUTER]], -1
; CHECK-NEXT: [[INDVARS_IV_NEXT2:%.*]] = zext nneg i32 [[IV_OUTER_1]] to i64
; CHECK-NEXT: [[INDVARS_IV1:%.*]] = phi i64 [ [[INDVARS_IV_NEXT2:%.*]], %[[PH]] ], [ [[TMP0]], %[[ENTRY]] ]
; CHECK-NEXT: [[INDVARS_IV_NEXT2]] = add nsw i64 [[INDVARS_IV1]], -1
; CHECK-NEXT: [[GEP_OUTER:%.*]] = getelementptr i8, ptr [[PTR]], i64 [[INDVARS_IV_NEXT2]]
; CHECK-NEXT: store i8 0, ptr [[GEP_OUTER]], align 1
; CHECK-NEXT: [[EXIT_COND_OUTER:%.*]] = icmp samesign ugt i32 [[IV_OUTER]], 1
; CHECK-NEXT: [[EXIT_COND_OUTER:%.*]] = icmp samesign ugt i64 [[INDVARS_IV1]], 1
; CHECK-NEXT: br i1 [[EXIT_COND_OUTER]], label %[[INNER_LOOP_PREHEADER:.*]], label %[[PH]]
; CHECK: [[INNER_LOOP_PREHEADER]]:
; CHECK-NEXT: [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[INDVARS_IV1]] to i64
; CHECK-NEXT: br label %[[INNER_LOOP:.*]]
; CHECK: [[INNER_LOOP]]:
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ 0, %[[INNER_LOOP_PREHEADER]] ], [ [[INDVARS_IV_NEXT:%.*]], %[[INNER_LOOP]] ]
; CHECK-NEXT: [[GEP_INNER:%.*]] = getelementptr i8, ptr [[PTR]], i64 [[INDVARS_IV]]
; CHECK-NEXT: store i8 0, ptr [[GEP_INNER]], align 1
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i64 [[INDVARS_IV_NEXT]], [[WIDE_TRIP_COUNT]]
; CHECK-NEXT: br i1 [[EXITCOND]], label %[[INNER_LOOP]], label %[[PH_LOOPEXIT]]
; CHECK-NEXT: [[EXIT_COND_INNER:%.*]] = icmp slt i64 [[INDVARS_IV_NEXT]], [[INDVARS_IV_NEXT2]]
; CHECK-NEXT: br i1 [[EXIT_COND_INNER]], label %[[INNER_LOOP]], label %[[PH_LOOPEXIT]]
; CHECK: [[EXIT:.*:]]
; CHECK-NEXT: ret i32 0
;
@ -428,32 +424,28 @@ define i32 @iv_sext_sext_gt_slt(i32 %iter.count, ptr %ptr) {
; CHECK-LABEL: define i32 @iv_sext_sext_gt_slt(
; CHECK-SAME: i32 [[ITER_COUNT:%.*]], ptr [[PTR:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: [[TMP1:%.*]] = add nsw i32 [[ITER_COUNT]], -1
; CHECK-NEXT: [[TMP0:%.*]] = sext i32 [[ITER_COUNT]] to i64
; CHECK-NEXT: br label %[[OUTER_LOOP:.*]]
; CHECK: [[PH_LOOPEXIT:.*]]:
; CHECK-NEXT: br label %[[PH:.*]]
; CHECK: [[PH]]:
; CHECK-NEXT: [[INDVARS_IV_NEXT3:%.*]] = add i32 [[INDVARS_IV2:%.*]], -1
; CHECK-NEXT: br label %[[OUTER_LOOP]]
; CHECK: [[OUTER_LOOP]]:
; CHECK-NEXT: [[INDVARS_IV1:%.*]] = phi i64 [ [[INDVARS_IV_NEXT2:%.*]], %[[PH]] ], [ [[TMP0]], %[[ENTRY]] ]
; CHECK-NEXT: [[INDVARS_IV2]] = phi i32 [ [[INDVARS_IV_NEXT3]], %[[PH]] ], [ [[TMP1]], %[[ENTRY]] ]
; CHECK-NEXT: [[INDVARS_IV_NEXT2]] = add nsw i64 [[INDVARS_IV1]], -1
; CHECK-NEXT: [[GEP_OUTER:%.*]] = getelementptr i8, ptr [[PTR]], i64 [[INDVARS_IV_NEXT2]]
; CHECK-NEXT: store i8 0, ptr [[GEP_OUTER]], align 1
; CHECK-NEXT: [[EXIT_COND_OUTER:%.*]] = icmp samesign ugt i64 [[INDVARS_IV1]], 1
; CHECK-NEXT: br i1 [[EXIT_COND_OUTER]], label %[[INNER_LOOP_PREHEADER:.*]], label %[[PH]]
; CHECK: [[INNER_LOOP_PREHEADER]]:
; CHECK-NEXT: [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[INDVARS_IV2]] to i64
; CHECK-NEXT: br label %[[INNER_LOOP:.*]]
; CHECK: [[INNER_LOOP]]:
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ 0, %[[INNER_LOOP_PREHEADER]] ], [ [[INDVARS_IV_NEXT:%.*]], %[[INNER_LOOP]] ]
; CHECK-NEXT: [[GEP_INNER:%.*]] = getelementptr i8, ptr [[PTR]], i64 [[INDVARS_IV]]
; CHECK-NEXT: store i8 0, ptr [[GEP_INNER]], align 1
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i64 [[INDVARS_IV_NEXT]], [[WIDE_TRIP_COUNT]]
; CHECK-NEXT: br i1 [[EXITCOND]], label %[[INNER_LOOP]], label %[[PH_LOOPEXIT]]
; CHECK-NEXT: [[EXIT_COND_INNER:%.*]] = icmp slt i64 [[INDVARS_IV_NEXT]], [[INDVARS_IV_NEXT2]]
; CHECK-NEXT: br i1 [[EXIT_COND_INNER]], label %[[INNER_LOOP]], label %[[PH_LOOPEXIT]]
; CHECK: [[EXIT:.*:]]
; CHECK-NEXT: ret i32 0
;