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Merge commit '15400236e55a' from apple/main into swift/next
2 parents a8452c4 + 1540023 commit e900f7c

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+7
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5 files changed

+7
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‎llvm/include/llvm/Analysis/ScalarEvolution.h

Lines changed: 0 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -1489,13 +1489,6 @@ class ScalarEvolution {
14891489
ConstantRange getRangeForAffineAR(const SCEV *Start, const SCEV *Stop,
14901490
const SCEV *MaxBECount, unsigned BitWidth);
14911491

1492-
/// Determines the range for the affine non-self-wrapping SCEVAddRecExpr {\p
1493-
/// Start,+,\p Stop}<nw>.
1494-
ConstantRange getRangeForAffineNoSelfWrappingAR(const SCEVAddRecExpr *AddRec,
1495-
const SCEV *MaxBECount,
1496-
unsigned BitWidth,
1497-
RangeSignHint SignHint);
1498-
14991492
/// Try to compute a range for the affine SCEVAddRecExpr {\p Start,+,\p
15001493
/// Stop} by "factoring out" a ternary expression from the add recurrence.
15011494
/// Helper called by \c getRange.

‎llvm/lib/Analysis/ScalarEvolution.cpp

Lines changed: 0 additions & 72 deletions
Original file line numberDiff line numberDiff line change
@@ -5509,17 +5509,6 @@ ScalarEvolution::getRangeRef(const SCEV *S,
55095509
ConservativeResult =
55105510
ConservativeResult.intersectWith(RangeFromFactoring, RangeType);
55115511
}
5512-
5513-
// Now try symbolic BE count and more powerful methods.
5514-
MaxBECount = computeMaxBackedgeTakenCount(AddRec->getLoop());
5515-
if (!isa<SCEVCouldNotCompute>(MaxBECount) &&
5516-
getTypeSizeInBits(MaxBECount->getType()) <= BitWidth &&
5517-
AddRec->hasNoSelfWrap()) {
5518-
auto RangeFromAffineNew = getRangeForAffineNoSelfWrappingAR(
5519-
AddRec, MaxBECount, BitWidth, SignHint);
5520-
ConservativeResult =
5521-
ConservativeResult.intersectWith(RangeFromAffineNew, RangeType);
5522-
}
55235512
}
55245513

55255514
return setRange(AddRec, SignHint, std::move(ConservativeResult));
@@ -5689,67 +5678,6 @@ ConstantRange ScalarEvolution::getRangeForAffineAR(const SCEV *Start,
56895678
return SR.intersectWith(UR, ConstantRange::Smallest);
56905679
}
56915680

5692-
ConstantRange ScalarEvolution::getRangeForAffineNoSelfWrappingAR(
5693-
const SCEVAddRecExpr *AddRec, const SCEV *MaxBECount, unsigned BitWidth,
5694-
ScalarEvolution::RangeSignHint SignHint) {
5695-
assert(AddRec->isAffine() && "Non-affine AddRecs are not suppored!\n");
5696-
assert(AddRec->hasNoSelfWrap() &&
5697-
"This only works for non-self-wrapping AddRecs!");
5698-
const bool IsSigned = SignHint == HINT_RANGE_SIGNED;
5699-
const SCEV *Step = AddRec->getStepRecurrence(*this);
5700-
// Let's make sure that we can prove that we do not self-wrap during
5701-
// MaxBECount iterations. We need this because MaxBECount is a maximum
5702-
// iteration count estimate, and we might infer nw from some exit for which we
5703-
// do not know max exit count (or any other side reasoning).
5704-
// TODO: Turn into assert at some point.
5705-
MaxBECount = getNoopOrZeroExtend(MaxBECount, AddRec->getType());
5706-
const SCEV *RangeWidth = getNegativeSCEV(getOne(AddRec->getType()));
5707-
const SCEV *StepAbs = getUMinExpr(Step, getNegativeSCEV(Step));
5708-
const SCEV *MaxItersWithoutWrap = getUDivExpr(RangeWidth, StepAbs);
5709-
if (!isKnownPredicate(ICmpInst::ICMP_ULE, MaxBECount, MaxItersWithoutWrap))
5710-
return ConstantRange::getFull(BitWidth);
5711-
5712-
ICmpInst::Predicate LEPred =
5713-
IsSigned ? ICmpInst::ICMP_SLE : ICmpInst::ICMP_ULE;
5714-
ICmpInst::Predicate GEPred =
5715-
IsSigned ? ICmpInst::ICMP_SGE : ICmpInst::ICMP_UGE;
5716-
const SCEV *Start = AddRec->getStart();
5717-
const SCEV *End = AddRec->evaluateAtIteration(MaxBECount, *this);
5718-
// We could handle non-constant End, but it harms compile time a lot.
5719-
if (!isa<SCEVConstant>(End))
5720-
return ConstantRange::getFull(BitWidth);
5721-
5722-
// We know that there is no self-wrap. Let's take Start and End values and
5723-
// look at all intermediate values V1, V2, ..., Vn that IndVar takes during
5724-
// the iteration. They either lie inside the range [Min(Start, End),
5725-
// Max(Start, End)] or outside it:
5726-
//
5727-
// Case 1: RangeMin ... Start V1 ... VN End ... RangeMax;
5728-
// Case 2: RangeMin Vk ... V1 Start ... End Vn ... Vk + 1 RangeMax;
5729-
//
5730-
// No self wrap flag guarantees that the intermediate values cannot be BOTH
5731-
// outside and inside the range [Min(Start, End), Max(Start, End)]. Using that
5732-
// knowledge, let's try to prove that we are dealing with Case 1. It is so if
5733-
// Start <= End and step is positive, or Start >= End and step is negative.
5734-
ConstantRange StartRange =
5735-
IsSigned ? getSignedRange(Start) : getUnsignedRange(Start);
5736-
ConstantRange EndRange =
5737-
IsSigned ? getSignedRange(End) : getUnsignedRange(End);
5738-
ConstantRange RangeBetween = StartRange.unionWith(EndRange);
5739-
// If they already cover full iteration space, we will know nothing useful
5740-
// even if we prove what we want to prove.
5741-
if (RangeBetween.isFullSet())
5742-
return RangeBetween;
5743-
5744-
if (isKnownPositive(Step) &&
5745-
isKnownViaNonRecursiveReasoning(LEPred, Start, End))
5746-
return RangeBetween;
5747-
else if (isKnownNegative(Step) &&
5748-
isKnownViaNonRecursiveReasoning(GEPred, Start, End))
5749-
return RangeBetween;
5750-
return ConstantRange::getFull(BitWidth);
5751-
}
5752-
57535681
ConstantRange ScalarEvolution::getRangeViaFactoring(const SCEV *Start,
57545682
const SCEV *Step,
57555683
const SCEV *MaxBECount,

‎llvm/test/Analysis/ScalarEvolution/no-wrap-symbolic-becount.ll

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -7,7 +7,7 @@ define i32 @test_01(i32 %start, i32* %p, i32* %q) {
77
; CHECK-NEXT: %0 = zext i32 %start to i64
88
; CHECK-NEXT: --> (zext i32 %start to i64) U: [0,4294967296) S: [0,4294967296)
99
; CHECK-NEXT: %indvars.iv = phi i64 [ %indvars.iv.next, %backedge ], [ %0, %entry ]
10-
; CHECK-NEXT: --> {(zext i32 %start to i64),+,-1}<nsw><%loop> U: [0,4294967296) S: [0,4294967296) Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
10+
; CHECK-NEXT: --> {(zext i32 %start to i64),+,-1}<nsw><%loop> U: [-4294967295,4294967296) S: [-4294967295,4294967296) Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
1111
; CHECK-NEXT: %iv = phi i32 [ %start, %entry ], [ %iv.next, %backedge ]
1212
; CHECK-NEXT: --> {%start,+,-1}<%loop> U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
1313
; CHECK-NEXT: %iv.next = add i32 %iv, -1
@@ -21,7 +21,7 @@ define i32 @test_01(i32 %start, i32* %p, i32* %q) {
2121
; CHECK-NEXT: %stop = load i32, i32* %load.addr, align 4
2222
; CHECK-NEXT: --> %stop U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
2323
; CHECK-NEXT: %indvars.iv.next = add nsw i64 %indvars.iv, -1
24-
; CHECK-NEXT: --> {(-1 + (zext i32 %start to i64))<nsw>,+,-1}<nsw><%loop> U: [-4294967296,4294967295) S: [-1,4294967295) Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
24+
; CHECK-NEXT: --> {(-1 + (zext i32 %start to i64))<nsw>,+,-1}<nsw><%loop> U: [-4294967296,4294967295) S: [-4294967296,4294967295) Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
2525
; CHECK-NEXT: Determining loop execution counts for: @test_01
2626
; CHECK-NEXT: Loop %loop: <multiple exits> Unpredictable backedge-taken count.
2727
; CHECK-NEXT: exit count for loop: (zext i32 %start to i64)

‎llvm/test/Transforms/IndVarSimplify/X86/eliminate-trunc.ll

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -474,7 +474,7 @@ define void @test_10(i32 %n) {
474474
; CHECK-NEXT: [[TMP1:%.*]] = zext i32 [[TMP0]] to i64
475475
; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i64 [[TMP1]], 90
476476
; CHECK-NEXT: [[UMIN:%.*]] = select i1 [[TMP2]], i64 [[TMP1]], i64 90
477-
; CHECK-NEXT: [[TMP3:%.*]] = add nuw nsw i64 [[UMIN]], -99
477+
; CHECK-NEXT: [[TMP3:%.*]] = add i64 [[UMIN]], -99
478478
; CHECK-NEXT: br label [[LOOP:%.*]]
479479
; CHECK: loop:
480480
; CHECK-NEXT: [[IV:%.*]] = phi i64 [ -100, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]

‎llvm/test/Transforms/IndVarSimplify/promote-iv-to-eliminate-casts.ll

Lines changed: 4 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -196,7 +196,7 @@ define void @promote_latch_condition_decrementing_loop_01(i32* %p, i32* %a) {
196196
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], [[LOOP]] ], [ [[TMP0]], [[PREHEADER]] ]
197197
; CHECK-NEXT: [[EL:%.*]] = getelementptr inbounds i32, i32* [[A:%.*]], i64 [[INDVARS_IV]]
198198
; CHECK-NEXT: store atomic i32 0, i32* [[EL]] unordered, align 4
199-
; CHECK-NEXT: [[LOOPCOND:%.*]] = icmp ult i64 [[INDVARS_IV]], 1
199+
; CHECK-NEXT: [[LOOPCOND:%.*]] = icmp slt i64 [[INDVARS_IV]], 1
200200
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nsw i64 [[INDVARS_IV]], -1
201201
; CHECK-NEXT: br i1 [[LOOPCOND]], label [[LOOPEXIT_LOOPEXIT:%.*]], label [[LOOP]]
202202
;
@@ -241,7 +241,7 @@ define void @promote_latch_condition_decrementing_loop_02(i32* %p, i32* %a) {
241241
; CHECK-NEXT: [[EL:%.*]] = getelementptr inbounds i32, i32* [[A:%.*]], i64 [[INDVARS_IV]]
242242
; CHECK-NEXT: store atomic i32 0, i32* [[EL]] unordered, align 4
243243
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nsw i64 [[INDVARS_IV]], -1
244-
; CHECK-NEXT: [[LOOPCOND:%.*]] = icmp ult i64 [[INDVARS_IV]], 1
244+
; CHECK-NEXT: [[LOOPCOND:%.*]] = icmp slt i64 [[INDVARS_IV]], 1
245245
; CHECK-NEXT: br i1 [[LOOPCOND]], label [[LOOPEXIT_LOOPEXIT:%.*]], label [[LOOP]]
246246
;
247247

@@ -285,7 +285,7 @@ define void @promote_latch_condition_decrementing_loop_03(i32* %p, i32* %a) {
285285
; CHECK-NEXT: [[EL:%.*]] = getelementptr inbounds i32, i32* [[A:%.*]], i64 [[INDVARS_IV]]
286286
; CHECK-NEXT: store atomic i32 0, i32* [[EL]] unordered, align 4
287287
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nsw i64 [[INDVARS_IV]], -1
288-
; CHECK-NEXT: [[LOOPCOND:%.*]] = icmp ult i64 [[INDVARS_IV]], 1
288+
; CHECK-NEXT: [[LOOPCOND:%.*]] = icmp slt i64 [[INDVARS_IV]], 1
289289
; CHECK-NEXT: br i1 [[LOOPCOND]], label [[LOOPEXIT_LOOPEXIT:%.*]], label [[LOOP]]
290290
;
291291

@@ -336,7 +336,7 @@ define void @promote_latch_condition_decrementing_loop_04(i32* %p, i32* %a, i1 %
336336
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], [[LOOP]] ], [ [[TMP0]], [[PREHEADER]] ]
337337
; CHECK-NEXT: [[EL:%.*]] = getelementptr inbounds i32, i32* [[A:%.*]], i64 [[INDVARS_IV]]
338338
; CHECK-NEXT: store atomic i32 0, i32* [[EL]] unordered, align 4
339-
; CHECK-NEXT: [[LOOPCOND:%.*]] = icmp ult i64 [[INDVARS_IV]], 1
339+
; CHECK-NEXT: [[LOOPCOND:%.*]] = icmp slt i64 [[INDVARS_IV]], 1
340340
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nsw i64 [[INDVARS_IV]], -1
341341
; CHECK-NEXT: br i1 [[LOOPCOND]], label [[LOOPEXIT_LOOPEXIT:%.*]], label [[LOOP]]
342342
;

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