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Reland "[compiler] Fix more truncation bugs in SimplifiedLowering"

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This is a reland of 47077d9449 without
changes. The revert was false alarm.

Original change's description:
> [compiler] Fix more truncation bugs in SimplifiedLowering
>
> Bug: chromium:1200490
> Change-Id: I3555b6d99bdb4b4e7c302a43a82c17e8bff84ebe
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2840452
> Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
> Commit-Queue: Georg Neis <neis@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#74097}

Bug: chromium:1200490
Change-Id: I75cac59050bc393d157a1ee5bed776c8986a7bbe
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2843817
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74105}
This commit is contained in:
Georg Neis 2021-04-20 18:19:42 +02:00 committed by Commit Bot
parent fd16e67e49
commit e4a580c910
1 changed files with 42 additions and 26 deletions
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68
src/compiler/simplified-lowering.cc
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@ -1424,17 +1424,31 @@ class RepresentationSelector {
return jsgraph_->simplified();
}
void LowerToCheckedInt32Mul(Node* node, Truncation truncation,
Type input0_type, Type input1_type) {
// If one of the inputs is positive and/or truncation is being applied,
// there is no need to return -0.
CheckForMinusZeroMode mz_mode =
truncation.IdentifiesZeroAndMinusZero() ||
IsSomePositiveOrderedNumber(input0_type) ||
IsSomePositiveOrderedNumber(input1_type)
? CheckForMinusZeroMode::kDontCheckForMinusZero
: CheckForMinusZeroMode::kCheckForMinusZero;
ChangeOp(node, simplified()->CheckedInt32Mul(mz_mode));
template <Phase T>
void VisitForCheckedInt32Mul(Node* node, Truncation truncation,
Type input0_type, Type input1_type,
UseInfo input_use) {
DCHECK_EQ(node->opcode(), IrOpcode::kSpeculativeNumberMultiply);
// A -0 input is impossible or will cause a deopt.
DCHECK(BothInputsAre(node, Type::Signed32()) ||
!input_use.truncation().IdentifiesZeroAndMinusZero());
CheckForMinusZeroMode mz_mode;
Type restriction;
if (IsSomePositiveOrderedNumber(input0_type) ||
IsSomePositiveOrderedNumber(input1_type)) {
mz_mode = CheckForMinusZeroMode::kDontCheckForMinusZero;
restriction = Type::Signed32();
} else if (truncation.IdentifiesZeroAndMinusZero()) {
mz_mode = CheckForMinusZeroMode::kDontCheckForMinusZero;
restriction = Type::Signed32OrMinusZero();
} else {
mz_mode = CheckForMinusZeroMode::kCheckForMinusZero;
restriction = Type::Signed32();
}
VisitBinop<T>(node, input_use, MachineRepresentation::kWord32, restriction);
if (lower<T>()) ChangeOp(node, simplified()->CheckedInt32Mul(mz_mode));
}
void ChangeToInt32OverflowOp(Node* node) {
@ -1622,12 +1636,22 @@ class RepresentationSelector {
VisitBinop<T>(node, lhs_use, rhs_use, MachineRepresentation::kWord32);
if (lower<T>()) DeferReplacement(node, lowering->Int32Mod(node));
} else if (BothInputsAre(node, Type::Unsigned32OrMinusZeroOrNaN())) {
Type const restriction =
truncation.IdentifiesZeroAndMinusZero() &&
TypeOf(node->InputAt(0)).Maybe(Type::MinusZero())
? Type::Unsigned32OrMinusZero()
: Type::Unsigned32();
VisitBinop<T>(node, lhs_use, rhs_use, MachineRepresentation::kWord32,
Type::Unsigned32());
restriction);
if (lower<T>()) ChangeToUint32OverflowOp(node);
} else {
Type const restriction =
truncation.IdentifiesZeroAndMinusZero() &&
TypeOf(node->InputAt(0)).Maybe(Type::MinusZero())
? Type::Signed32OrMinusZero()
: Type::Signed32();
VisitBinop<T>(node, lhs_use, rhs_use, MachineRepresentation::kWord32,
Type::Signed32());
restriction);
if (lower<T>()) ChangeToInt32OverflowOp(node);
}
return;
@ -2261,22 +2285,16 @@ class RepresentationSelector {
if (BothInputsAre(node, Type::Signed32())) {
// If both inputs and feedback are int32, use the overflow op.
if (hint == NumberOperationHint::kSignedSmall) {
VisitBinop<T>(node, UseInfo::TruncatingWord32(),
MachineRepresentation::kWord32, Type::Signed32());
if (lower<T>()) {
LowerToCheckedInt32Mul(node, truncation, input0_type,
input1_type);
}
VisitForCheckedInt32Mul<T>(node, truncation, input0_type,
input1_type,
UseInfo::TruncatingWord32());
return;
}
}
if (hint == NumberOperationHint::kSignedSmall) {
VisitBinop<T>(node, CheckedUseInfoAsWord32FromHint(hint),
MachineRepresentation::kWord32, Type::Signed32());
if (lower<T>()) {
LowerToCheckedInt32Mul(node, truncation, input0_type, input1_type);
}
VisitForCheckedInt32Mul<T>(node, truncation, input0_type, input1_type,
CheckedUseInfoAsWord32FromHint(hint));
return;
}
@ -4011,7 +4029,6 @@ template <>
void RepresentationSelector::SetOutput<RETYPE>(
Node* node, MachineRepresentation representation, Type restriction_type) {
NodeInfo* const info = GetInfo(node);
DCHECK(info->restriction_type().Is(restriction_type));
DCHECK(restriction_type.Is(info->restriction_type()));
info->set_output(representation);
}
@ -4021,7 +4038,6 @@ void RepresentationSelector::SetOutput<LOWER>(
Node* node, MachineRepresentation representation, Type restriction_type) {
NodeInfo* const info = GetInfo(node);
DCHECK_EQ(info->representation(), representation);
DCHECK(info->restriction_type().Is(restriction_type));
DCHECK(restriction_type.Is(info->restriction_type()));
USE(info);
}