Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(112)

Unified Diff: runtime/vm/intermediate_language.cc

Issue 442293002: Consolidate all range analysis related code in a separate file. (Closed) Base URL: https://dart.googlecode.com/svn/branches/bleeding_edge/dart
Patch Set: Created 6 years, 4 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
« no previous file with comments | « runtime/vm/intermediate_language.h ('k') | runtime/vm/intermediate_language_arm.cc » ('j') | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
Index: runtime/vm/intermediate_language.cc
diff --git a/runtime/vm/intermediate_language.cc b/runtime/vm/intermediate_language.cc
index c564930ec7955da7bc676bedeb586feb5e91b0ff..118e6522785e4646c971aa157781351c378535af 100644
--- a/runtime/vm/intermediate_language.cc
+++ b/runtime/vm/intermediate_language.cc
@@ -12,6 +12,7 @@
#include "vm/flow_graph_builder.h"
#include "vm/flow_graph_compiler.h"
#include "vm/flow_graph_optimizer.h"
+#include "vm/flow_graph_range_analysis.h"
#include "vm/locations.h"
#include "vm/object.h"
#include "vm/object_store.h"
@@ -2582,579 +2583,6 @@ void Environment::DeepCopyToOuter(Isolate* isolate, Instruction* instr) const {
}
-RangeBoundary RangeBoundary::FromDefinition(Definition* defn, int64_t offs) {
- if (defn->IsConstant() && defn->AsConstant()->value().IsSmi()) {
- return FromConstant(Smi::Cast(defn->AsConstant()->value()).Value() + offs);
- }
- return RangeBoundary(kSymbol, reinterpret_cast<intptr_t>(defn), offs);
-}
-
-
-RangeBoundary RangeBoundary::LowerBound() const {
- if (IsInfinity()) {
- return NegativeInfinity();
- }
- if (IsConstant()) return *this;
- return Add(Range::ConstantMin(symbol()->range()),
- RangeBoundary::FromConstant(offset_),
- NegativeInfinity());
-}
-
-
-RangeBoundary RangeBoundary::UpperBound() const {
- if (IsInfinity()) {
- return PositiveInfinity();
- }
- if (IsConstant()) return *this;
- return Add(Range::ConstantMax(symbol()->range()),
- RangeBoundary::FromConstant(offset_),
- PositiveInfinity());
-}
-
-
-RangeBoundary RangeBoundary::Add(const RangeBoundary& a,
- const RangeBoundary& b,
- const RangeBoundary& overflow) {
- if (a.IsInfinity() || b.IsInfinity()) return overflow;
-
- ASSERT(a.IsConstant() && b.IsConstant());
- if (Utils::WillAddOverflow(a.ConstantValue(), b.ConstantValue())) {
- return overflow;
- }
-
- int64_t result = a.ConstantValue() + b.ConstantValue();
-
- return RangeBoundary::FromConstant(result);
-}
-
-
-RangeBoundary RangeBoundary::Sub(const RangeBoundary& a,
- const RangeBoundary& b,
- const RangeBoundary& overflow) {
- if (a.IsInfinity() || b.IsInfinity()) return overflow;
- ASSERT(a.IsConstant() && b.IsConstant());
- if (Utils::WillSubOverflow(a.ConstantValue(), b.ConstantValue())) {
- return overflow;
- }
-
- int64_t result = a.ConstantValue() - b.ConstantValue();
-
- return RangeBoundary::FromConstant(result);
-}
-
-
-bool RangeBoundary::SymbolicAdd(const RangeBoundary& a,
- const RangeBoundary& b,
- RangeBoundary* result) {
- if (a.IsSymbol() && b.IsConstant()) {
- if (Utils::WillAddOverflow(a.offset(), b.ConstantValue())) {
- return false;
- }
-
- const int64_t offset = a.offset() + b.ConstantValue();
-
- *result = RangeBoundary::FromDefinition(a.symbol(), offset);
- return true;
- } else if (b.IsSymbol() && a.IsConstant()) {
- return SymbolicAdd(b, a, result);
- }
- return false;
-}
-
-
-bool RangeBoundary::SymbolicSub(const RangeBoundary& a,
- const RangeBoundary& b,
- RangeBoundary* result) {
- if (a.IsSymbol() && b.IsConstant()) {
- if (Utils::WillSubOverflow(a.offset(), b.ConstantValue())) {
- return false;
- }
-
- const int64_t offset = a.offset() - b.ConstantValue();
-
- *result = RangeBoundary::FromDefinition(a.symbol(), offset);
- return true;
- }
- return false;
-}
-
-
-static Definition* UnwrapConstraint(Definition* defn) {
- while (defn->IsConstraint()) {
- defn = defn->AsConstraint()->value()->definition();
- }
- return defn;
-}
-
-
-static bool AreEqualDefinitions(Definition* a, Definition* b) {
- a = UnwrapConstraint(a);
- b = UnwrapConstraint(b);
- return (a == b) ||
- (a->AllowsCSE() &&
- a->Dependencies().IsNone() &&
- b->AllowsCSE() &&
- b->Dependencies().IsNone() &&
- a->Equals(b));
-}
-
-
-// Returns true if two range boundaries refer to the same symbol.
-static bool DependOnSameSymbol(const RangeBoundary& a, const RangeBoundary& b) {
- return a.IsSymbol() && b.IsSymbol() &&
- AreEqualDefinitions(a.symbol(), b.symbol());
-}
-
-
-bool RangeBoundary::Equals(const RangeBoundary& other) const {
- if (IsConstant() && other.IsConstant()) {
- return ConstantValue() == other.ConstantValue();
- } else if (IsInfinity() && other.IsInfinity()) {
- return kind() == other.kind();
- } else if (IsSymbol() && other.IsSymbol()) {
- return (offset() == other.offset()) && DependOnSameSymbol(*this, other);
- } else if (IsUnknown() && other.IsUnknown()) {
- return true;
- }
- return false;
-}
-
-
-RangeBoundary RangeBoundary::Shl(const RangeBoundary& value_boundary,
- int64_t shift_count,
- const RangeBoundary& overflow) {
- ASSERT(value_boundary.IsConstant());
- ASSERT(shift_count >= 0);
- int64_t limit = 64 - shift_count;
- int64_t value = value_boundary.ConstantValue();
-
- if ((value == 0) ||
- (shift_count == 0) ||
- ((limit > 0) && Utils::IsInt(static_cast<int>(limit), value))) {
- // Result stays in 64 bit range.
- int64_t result = value << shift_count;
- return RangeBoundary(result);
- }
-
- return overflow;
-}
-
-
-static RangeBoundary CanonicalizeBoundary(const RangeBoundary& a,
- const RangeBoundary& overflow) {
- if (a.IsConstant() || a.IsInfinity()) {
- return a;
- }
-
- int64_t offset = a.offset();
- Definition* symbol = a.symbol();
-
- bool changed;
- do {
- changed = false;
- if (symbol->IsConstraint()) {
- symbol = symbol->AsConstraint()->value()->definition();
- changed = true;
- } else if (symbol->IsBinarySmiOp()) {
- BinarySmiOpInstr* op = symbol->AsBinarySmiOp();
- Definition* left = op->left()->definition();
- Definition* right = op->right()->definition();
- switch (op->op_kind()) {
- case Token::kADD:
- if (right->IsConstant()) {
- int64_t rhs = Smi::Cast(right->AsConstant()->value()).Value();
- if (Utils::WillAddOverflow(offset, rhs)) {
- return overflow;
- }
- offset += rhs;
- symbol = left;
- changed = true;
- } else if (left->IsConstant()) {
- int64_t rhs = Smi::Cast(left->AsConstant()->value()).Value();
- if (Utils::WillAddOverflow(offset, rhs)) {
- return overflow;
- }
- offset += rhs;
- symbol = right;
- changed = true;
- }
- break;
-
- case Token::kSUB:
- if (right->IsConstant()) {
- int64_t rhs = Smi::Cast(right->AsConstant()->value()).Value();
- if (Utils::WillSubOverflow(offset, rhs)) {
- return overflow;
- }
- offset -= rhs;
- symbol = left;
- changed = true;
- }
- break;
-
- default:
- break;
- }
- }
- } while (changed);
-
- return RangeBoundary::FromDefinition(symbol, offset);
-}
-
-
-static bool CanonicalizeMaxBoundary(RangeBoundary* a) {
- if (!a->IsSymbol()) return false;
-
- Range* range = a->symbol()->range();
- if ((range == NULL) || !range->max().IsSymbol()) return false;
-
-
- if (Utils::WillAddOverflow(range->max().offset(), a->offset())) {
- *a = RangeBoundary::PositiveInfinity();
- return true;
- }
-
- const int64_t offset = range->max().offset() + a->offset();
-
-
- *a = CanonicalizeBoundary(
- RangeBoundary::FromDefinition(range->max().symbol(), offset),
- RangeBoundary::PositiveInfinity());
-
- return true;
-}
-
-
-static bool CanonicalizeMinBoundary(RangeBoundary* a) {
- if (!a->IsSymbol()) return false;
-
- Range* range = a->symbol()->range();
- if ((range == NULL) || !range->min().IsSymbol()) return false;
-
- if (Utils::WillAddOverflow(range->min().offset(), a->offset())) {
- *a = RangeBoundary::NegativeInfinity();
- return true;
- }
-
- const int64_t offset = range->min().offset() + a->offset();
-
- *a = CanonicalizeBoundary(
- RangeBoundary::FromDefinition(range->min().symbol(), offset),
- RangeBoundary::NegativeInfinity());
-
- return true;
-}
-
-
-RangeBoundary RangeBoundary::Min(RangeBoundary a, RangeBoundary b,
- RangeSize size) {
- ASSERT(!(a.IsNegativeInfinity() || b.IsNegativeInfinity()));
- ASSERT(!a.IsUnknown() || !b.IsUnknown());
- if (a.IsUnknown() && !b.IsUnknown()) {
- return b;
- }
- if (!a.IsUnknown() && b.IsUnknown()) {
- return a;
- }
- if (size == kRangeBoundarySmi) {
- if (a.IsSmiMaximumOrAbove() && !b.IsSmiMaximumOrAbove()) {
- return b;
- }
- if (!a.IsSmiMaximumOrAbove() && b.IsSmiMaximumOrAbove()) {
- return a;
- }
- } else {
- ASSERT(size == kRangeBoundaryInt64);
- if (a.IsMaximumOrAbove() && !b.IsMaximumOrAbove()) {
- return b;
- }
- if (!a.IsMaximumOrAbove() && b.IsMaximumOrAbove()) {
- return a;
- }
- }
-
- if (a.Equals(b)) {
- return b;
- }
-
- {
- RangeBoundary canonical_a =
- CanonicalizeBoundary(a, RangeBoundary::PositiveInfinity());
- RangeBoundary canonical_b =
- CanonicalizeBoundary(b, RangeBoundary::PositiveInfinity());
- do {
- if (DependOnSameSymbol(canonical_a, canonical_b)) {
- a = canonical_a;
- b = canonical_b;
- break;
- }
- } while (CanonicalizeMaxBoundary(&canonical_a) ||
- CanonicalizeMaxBoundary(&canonical_b));
- }
-
- if (DependOnSameSymbol(a, b)) {
- return (a.offset() <= b.offset()) ? a : b;
- }
-
- const int64_t min_a = a.UpperBound().Clamp(size).ConstantValue();
- const int64_t min_b = b.UpperBound().Clamp(size).ConstantValue();
-
- return RangeBoundary::FromConstant(Utils::Minimum(min_a, min_b));
-}
-
-
-RangeBoundary RangeBoundary::Max(RangeBoundary a, RangeBoundary b,
- RangeSize size) {
- ASSERT(!(a.IsPositiveInfinity() || b.IsPositiveInfinity()));
- ASSERT(!a.IsUnknown() || !b.IsUnknown());
- if (a.IsUnknown() && !b.IsUnknown()) {
- return b;
- }
- if (!a.IsUnknown() && b.IsUnknown()) {
- return a;
- }
- if (size == kRangeBoundarySmi) {
- if (a.IsSmiMinimumOrBelow() && !b.IsSmiMinimumOrBelow()) {
- return b;
- }
- if (!a.IsSmiMinimumOrBelow() && b.IsSmiMinimumOrBelow()) {
- return a;
- }
- } else {
- ASSERT(size == kRangeBoundaryInt64);
- if (a.IsMinimumOrBelow() && !b.IsMinimumOrBelow()) {
- return b;
- }
- if (!a.IsMinimumOrBelow() && b.IsMinimumOrBelow()) {
- return a;
- }
- }
- if (a.Equals(b)) {
- return b;
- }
-
- {
- RangeBoundary canonical_a =
- CanonicalizeBoundary(a, RangeBoundary::NegativeInfinity());
- RangeBoundary canonical_b =
- CanonicalizeBoundary(b, RangeBoundary::NegativeInfinity());
-
- do {
- if (DependOnSameSymbol(canonical_a, canonical_b)) {
- a = canonical_a;
- b = canonical_b;
- break;
- }
- } while (CanonicalizeMinBoundary(&canonical_a) ||
- CanonicalizeMinBoundary(&canonical_b));
- }
-
- if (DependOnSameSymbol(a, b)) {
- return (a.offset() <= b.offset()) ? b : a;
- }
-
- const int64_t max_a = a.LowerBound().Clamp(size).ConstantValue();
- const int64_t max_b = b.LowerBound().Clamp(size).ConstantValue();
-
- return RangeBoundary::FromConstant(Utils::Maximum(max_a, max_b));
-}
-
-
-int64_t RangeBoundary::ConstantValue() const {
- ASSERT(IsConstant());
- return value_;
-}
-
-
-void Definition::InferRange() {
- if (Type()->ToCid() == kSmiCid) {
- if (range_ == NULL) {
- range_ = Range::UnknownSmi();
- }
- } else if (IsMintDefinition()) {
- if (range_ == NULL) {
- range_ = Range::Unknown();
- }
- } else {
- // Only Smi and Mint supported.
- UNREACHABLE();
- }
-}
-
-
-void ConstantInstr::InferRange() {
- if (value_.IsSmi()) {
- if (range_ == NULL) {
- int64_t value = Smi::Cast(value_).Value();
- range_ = new Range(RangeBoundary::FromConstant(value),
- RangeBoundary::FromConstant(value));
- }
- } else if (value_.IsMint()) {
- if (range_ == NULL) {
- int64_t value = Mint::Cast(value_).value();
- range_ = new Range(RangeBoundary::FromConstant(value),
- RangeBoundary::FromConstant(value));
- }
- } else {
- // Only Smi and Mint supported.
- UNREACHABLE();
- }
-}
-
-
-void UnboxIntegerInstr::InferRange() {
- if (range_ == NULL) {
- Definition* unboxed = value()->definition();
- ASSERT(unboxed != NULL);
- Range* range = unboxed->range();
- if (range == NULL) {
- range_ = Range::Unknown();
- return;
- }
- range_ = new Range(range->min(), range->max());
- }
-}
-
-
-void ConstraintInstr::InferRange() {
- Range* value_range = value()->definition()->range();
-
- // Only constraining smi values.
- ASSERT(value()->IsSmiValue());
-
- RangeBoundary min;
- RangeBoundary max;
-
- {
- RangeBoundary value_min = (value_range == NULL) ?
- RangeBoundary() : value_range->min();
- RangeBoundary constraint_min = constraint()->min();
- min = RangeBoundary::Max(value_min, constraint_min,
- RangeBoundary::kRangeBoundarySmi);
- }
-
- ASSERT(!min.IsUnknown());
-
- {
- RangeBoundary value_max = (value_range == NULL) ?
- RangeBoundary() : value_range->max();
- RangeBoundary constraint_max = constraint()->max();
- max = RangeBoundary::Min(value_max, constraint_max,
- RangeBoundary::kRangeBoundarySmi);
- }
-
- ASSERT(!max.IsUnknown());
-
- range_ = new Range(min, max);
-
- // Mark branches that generate unsatisfiable constraints as constant.
- if (target() != NULL && range_->IsUnsatisfiable()) {
- BranchInstr* branch =
- target()->PredecessorAt(0)->last_instruction()->AsBranch();
- if (target() == branch->true_successor()) {
- // True unreachable.
- if (FLAG_trace_constant_propagation) {
- OS::Print("Range analysis: True unreachable (B%" Pd ")\n",
- branch->true_successor()->block_id());
- }
- branch->set_constant_target(branch->false_successor());
- } else {
- ASSERT(target() == branch->false_successor());
- // False unreachable.
- if (FLAG_trace_constant_propagation) {
- OS::Print("Range analysis: False unreachable (B%" Pd ")\n",
- branch->false_successor()->block_id());
- }
- branch->set_constant_target(branch->true_successor());
- }
- }
-}
-
-
-void LoadFieldInstr::InferRange() {
- if ((range_ == NULL) &&
- ((recognized_kind() == MethodRecognizer::kObjectArrayLength) ||
- (recognized_kind() == MethodRecognizer::kImmutableArrayLength))) {
- range_ = new Range(RangeBoundary::FromConstant(0),
- RangeBoundary::FromConstant(Array::kMaxElements));
- return;
- }
- if ((range_ == NULL) &&
- (recognized_kind() == MethodRecognizer::kTypedDataLength)) {
- range_ = new Range(RangeBoundary::FromConstant(0), RangeBoundary::MaxSmi());
- return;
- }
- if ((range_ == NULL) &&
- (recognized_kind() == MethodRecognizer::kStringBaseLength)) {
- range_ = new Range(RangeBoundary::FromConstant(0),
- RangeBoundary::FromConstant(String::kMaxElements));
- return;
- }
- Definition::InferRange();
-}
-
-
-
-void LoadIndexedInstr::InferRange() {
- switch (class_id()) {
- case kTypedDataInt8ArrayCid:
- range_ = new Range(RangeBoundary::FromConstant(-128),
- RangeBoundary::FromConstant(127));
- break;
- case kTypedDataUint8ArrayCid:
- case kTypedDataUint8ClampedArrayCid:
- case kExternalTypedDataUint8ArrayCid:
- case kExternalTypedDataUint8ClampedArrayCid:
- range_ = new Range(RangeBoundary::FromConstant(0),
- RangeBoundary::FromConstant(255));
- break;
- case kTypedDataInt16ArrayCid:
- range_ = new Range(RangeBoundary::FromConstant(-32768),
- RangeBoundary::FromConstant(32767));
- break;
- case kTypedDataUint16ArrayCid:
- range_ = new Range(RangeBoundary::FromConstant(0),
- RangeBoundary::FromConstant(65535));
- break;
- case kTypedDataInt32ArrayCid:
- if (Typed32BitIsSmi()) {
- range_ = Range::UnknownSmi();
- } else {
- range_ = new Range(RangeBoundary::FromConstant(kMinInt32),
- RangeBoundary::FromConstant(kMaxInt32));
- }
- break;
- case kTypedDataUint32ArrayCid:
- if (Typed32BitIsSmi()) {
- range_ = Range::UnknownSmi();
- } else {
- range_ = new Range(RangeBoundary::FromConstant(0),
- RangeBoundary::FromConstant(kMaxUint32));
- }
- break;
- case kOneByteStringCid:
- range_ = new Range(RangeBoundary::FromConstant(0),
- RangeBoundary::FromConstant(0xFF));
- break;
- case kTwoByteStringCid:
- range_ = new Range(RangeBoundary::FromConstant(0),
- RangeBoundary::FromConstant(0xFFFF));
- break;
- default:
- Definition::InferRange();
- break;
- }
-}
-
-
-void IfThenElseInstr::InferRange() {
- const intptr_t min = Utils::Minimum(if_true_, if_false_);
- const intptr_t max = Utils::Maximum(if_true_, if_false_);
- range_ = new Range(RangeBoundary::FromConstant(min),
- RangeBoundary::FromConstant(max));
-}
-
-
static bool BindsToSmiConstant(Value* value) {
return value->BindsToConstant() && value->BoundConstant().IsSmi();
}
@@ -3246,46 +2674,6 @@ bool IfThenElseInstr::Supports(ComparisonInstr* comparison,
}
-void PhiInstr::InferRange() {
- RangeBoundary new_min;
- RangeBoundary new_max;
-
- ASSERT(Type()->ToCid() == kSmiCid);
-
- for (intptr_t i = 0; i < InputCount(); i++) {
- Range* input_range = InputAt(i)->definition()->range();
- if (input_range == NULL) {
- range_ = Range::UnknownSmi();
- return;
- }
-
- if (new_min.IsUnknown()) {
- new_min = Range::ConstantMin(input_range);
- } else {
- new_min = RangeBoundary::Min(new_min,
- Range::ConstantMinSmi(input_range),
- RangeBoundary::kRangeBoundarySmi);
- }
-
- if (new_max.IsUnknown()) {
- new_max = Range::ConstantMax(input_range);
- } else {
- new_max = RangeBoundary::Max(new_max,
- Range::ConstantMaxSmi(input_range),
- RangeBoundary::kRangeBoundarySmi);
- }
- }
-
- ASSERT(new_min.IsUnknown() == new_max.IsUnknown());
- if (new_min.IsUnknown()) {
- range_ = Range::UnknownSmi();
- return;
- }
-
- range_ = new Range(new_min, new_max);
-}
-
-
bool PhiInstr::IsRedundant() const {
ASSERT(InputCount() > 1);
Definition* first = InputAt(0)->definition();
@@ -3297,543 +2685,11 @@ bool PhiInstr::IsRedundant() const {
}
-static bool IsArrayLength(Definition* defn) {
- if (defn == NULL) {
- return false;
- }
- LoadFieldInstr* load = defn->AsLoadField();
- return (load != NULL) && load->IsImmutableLengthLoad();
-}
-
-
-void BinarySmiOpInstr::InferRange() {
- // TODO(vegorov): canonicalize BinarySmiOp to always have constant on the
- // right and a non-constant on the left.
- Definition* left_defn = left()->definition();
-
- Range* left_range = left_defn->range();
- Range* right_range = right()->definition()->range();
-
- if ((left_range == NULL) || (right_range == NULL)) {
- range_ = Range::UnknownSmi();
- return;
- }
-
- Range* possible_range = Range::BinaryOp(op_kind(),
- left_range,
- right_range,
- left_defn);
-
- if ((range_ == NULL) && (possible_range == NULL)) {
- // Initialize.
- range_ = Range::UnknownSmi();
- return;
- }
-
- if (possible_range == NULL) {
- // Nothing new.
- return;
- }
-
- range_ = possible_range;
-
- ASSERT(!range_->min().IsUnknown() && !range_->max().IsUnknown());
- // Calculate overflowed status before clamping.
- const bool overflowed = range_->min().LowerBound().OverflowedSmi() ||
- range_->max().UpperBound().OverflowedSmi();
- set_overflow(overflowed);
-
- // Clamp value to be within smi range.
- range_->Clamp(RangeBoundary::kRangeBoundarySmi);
-}
-
-
-void BinaryMintOpInstr::InferRange() {
- // TODO(vegorov): canonicalize BinaryMintOpInstr to always have constant on
- // the right and a non-constant on the left.
- Definition* left_defn = left()->definition();
-
- Range* left_range = left_defn->range();
- Range* right_range = right()->definition()->range();
-
- if ((left_range == NULL) || (right_range == NULL)) {
- range_ = Range::Unknown();
- return;
- }
-
- Range* possible_range = Range::BinaryOp(op_kind(),
- left_range,
- right_range,
- left_defn);
-
- if ((range_ == NULL) && (possible_range == NULL)) {
- // Initialize.
- range_ = Range::Unknown();
- return;
- }
-
- if (possible_range == NULL) {
- // Nothing new.
- return;
- }
-
- range_ = possible_range;
-
- ASSERT(!range_->min().IsUnknown() && !range_->max().IsUnknown());
-
- // Calculate overflowed status before clamping.
- const bool overflowed = range_->min().LowerBound().OverflowedMint() ||
- range_->max().UpperBound().OverflowedMint();
- set_can_overflow(overflowed);
-
- // Clamp value to be within mint range.
- range_->Clamp(RangeBoundary::kRangeBoundaryInt64);
-}
-
-
-void ShiftMintOpInstr::InferRange() {
- Definition* left_defn = left()->definition();
-
- Range* left_range = left_defn->range();
- Range* right_range = right()->definition()->range();
-
- if ((left_range == NULL) || (right_range == NULL)) {
- range_ = Range::Unknown();
- return;
- }
-
- Range* possible_range = Range::BinaryOp(op_kind(),
- left_range,
- right_range,
- left_defn);
-
- if ((range_ == NULL) && (possible_range == NULL)) {
- // Initialize.
- range_ = Range::Unknown();
- return;
- }
-
- if (possible_range == NULL) {
- // Nothing new.
- return;
- }
-
- range_ = possible_range;
-
- ASSERT(!range_->min().IsUnknown() && !range_->max().IsUnknown());
-
- // Calculate overflowed status before clamping.
- const bool overflowed = range_->min().LowerBound().OverflowedMint() ||
- range_->max().UpperBound().OverflowedMint();
- set_can_overflow(overflowed);
-
- // Clamp value to be within mint range.
- range_->Clamp(RangeBoundary::kRangeBoundaryInt64);
-}
-
-
-void BoxIntegerInstr::InferRange() {
- Range* input_range = value()->definition()->range();
- if (input_range != NULL) {
- bool is_smi = !input_range->min().LowerBound().OverflowedSmi() &&
- !input_range->max().UpperBound().OverflowedSmi();
- set_is_smi(is_smi);
- // The output range is the same as the input range.
- range_ = input_range;
- }
-}
-
-
-bool Range::IsPositive() const {
- if (min().IsNegativeInfinity()) {
- return false;
- }
- if (min().LowerBound().ConstantValue() < 0) {
- return false;
- }
- if (max().IsPositiveInfinity()) {
- return true;
- }
- return max().UpperBound().ConstantValue() >= 0;
-}
-
-
-bool Range::OnlyLessThanOrEqualTo(int64_t val) const {
- if (max().IsPositiveInfinity()) {
- // Cannot be true.
- return false;
- }
- if (max().UpperBound().ConstantValue() > val) {
- // Not true.
- return false;
- }
- return true;
-}
-
-
-bool Range::OnlyGreaterThanOrEqualTo(int64_t val) const {
- if (min().IsNegativeInfinity()) {
- return false;
- }
- if (min().LowerBound().ConstantValue() < val) {
- return false;
- }
- return true;
-}
-
-
-// Inclusive.
-bool Range::IsWithin(int64_t min_int, int64_t max_int) const {
- RangeBoundary lower_min = min().LowerBound();
- if (lower_min.IsNegativeInfinity() || (lower_min.ConstantValue() < min_int)) {
- return false;
- }
- RangeBoundary upper_max = max().UpperBound();
- if (upper_max.IsPositiveInfinity() || (upper_max.ConstantValue() > max_int)) {
- return false;
- }
- return true;
-}
-
-
-bool Range::Overlaps(int64_t min_int, int64_t max_int) const {
- RangeBoundary lower = min().LowerBound();
- RangeBoundary upper = max().UpperBound();
- const int64_t this_min = lower.IsNegativeInfinity() ?
- RangeBoundary::kMin : lower.ConstantValue();
- const int64_t this_max = upper.IsPositiveInfinity() ?
- RangeBoundary::kMax : upper.ConstantValue();
- if ((this_min <= min_int) && (min_int <= this_max)) return true;
- if ((this_min <= max_int) && (max_int <= this_max)) return true;
- if ((min_int < this_min) && (max_int > this_max)) return true;
- return false;
-}
-
-
-bool Range::IsUnsatisfiable() const {
- // Infinity case: [+inf, ...] || [..., -inf]
- if (min().IsPositiveInfinity() || max().IsNegativeInfinity()) {
- return true;
- }
- // Constant case: For example [0, -1].
- if (Range::ConstantMin(this).ConstantValue() >
- Range::ConstantMax(this).ConstantValue()) {
- return true;
- }
- // Symbol case: For example [v+1, v].
- if (DependOnSameSymbol(min(), max()) && min().offset() > max().offset()) {
- return true;
- }
- return false;
-}
-
-
-void Range::Clamp(RangeBoundary::RangeSize size) {
- min_ = min_.Clamp(size);
- max_ = max_.Clamp(size);
-}
-
-
-void Range::Shl(const Range* left,
- const Range* right,
- RangeBoundary* result_min,
- RangeBoundary* result_max) {
- ASSERT(left != NULL);
- ASSERT(right != NULL);
- ASSERT(result_min != NULL);
- ASSERT(result_max != NULL);
- RangeBoundary left_max = Range::ConstantMax(left);
- RangeBoundary left_min = Range::ConstantMin(left);
- // A negative shift count always deoptimizes (and throws), so the minimum
- // shift count is zero.
- int64_t right_max = Utils::Maximum(Range::ConstantMax(right).ConstantValue(),
- static_cast<int64_t>(0));
- int64_t right_min = Utils::Maximum(Range::ConstantMin(right).ConstantValue(),
- static_cast<int64_t>(0));
-
- *result_min = RangeBoundary::Shl(
- left_min,
- left_min.ConstantValue() > 0 ? right_min : right_max,
- left_min.ConstantValue() > 0
- ? RangeBoundary::PositiveInfinity()
- : RangeBoundary::NegativeInfinity());
-
- *result_max = RangeBoundary::Shl(
- left_max,
- left_max.ConstantValue() > 0 ? right_max : right_min,
- left_max.ConstantValue() > 0
- ? RangeBoundary::PositiveInfinity()
- : RangeBoundary::NegativeInfinity());
-}
-
-
-void Range::Shr(const Range* left,
- const Range* right,
- RangeBoundary* result_min,
- RangeBoundary* result_max) {
- RangeBoundary left_max = Range::ConstantMax(left);
- RangeBoundary left_min = Range::ConstantMin(left);
- // A negative shift count always deoptimizes (and throws), so the minimum
- // shift count is zero.
- int64_t right_max = Utils::Maximum(Range::ConstantMax(right).ConstantValue(),
- static_cast<int64_t>(0));
- int64_t right_min = Utils::Maximum(Range::ConstantMin(right).ConstantValue(),
- static_cast<int64_t>(0));
-
- *result_min = RangeBoundary::Shr(
- left_min,
- left_min.ConstantValue() > 0 ? right_max : right_min);
-
- *result_max = RangeBoundary::Shr(
- left_max,
- left_max.ConstantValue() > 0 ? right_min : right_max);
-}
-
-
-bool Range::And(const Range* left_range,
- const Range* right_range,
- RangeBoundary* result_min,
- RangeBoundary* result_max) {
- ASSERT(left_range != NULL);
- ASSERT(right_range != NULL);
- ASSERT(result_min != NULL);
- ASSERT(result_max != NULL);
-
- if (Range::ConstantMin(right_range).ConstantValue() >= 0) {
- *result_min = RangeBoundary::FromConstant(0);
- *result_max = Range::ConstantMax(right_range);
- return true;
- }
-
- if (Range::ConstantMin(left_range).ConstantValue() >= 0) {
- *result_min = RangeBoundary::FromConstant(0);
- *result_max = Range::ConstantMax(left_range);
- return true;
- }
-
- return false;
-}
-
-
-void Range::Add(const Range* left_range,
- const Range* right_range,
- RangeBoundary* result_min,
- RangeBoundary* result_max,
- Definition* left_defn) {
- ASSERT(left_range != NULL);
- ASSERT(right_range != NULL);
- ASSERT(result_min != NULL);
- ASSERT(result_max != NULL);
-
- RangeBoundary left_min =
- IsArrayLength(left_defn) ?
- RangeBoundary::FromDefinition(left_defn) : left_range->min();
-
- RangeBoundary left_max =
- IsArrayLength(left_defn) ?
- RangeBoundary::FromDefinition(left_defn) : left_range->max();
-
- if (!RangeBoundary::SymbolicAdd(left_min, right_range->min(), result_min)) {
- *result_min = RangeBoundary::Add(left_range->min().LowerBound(),
- right_range->min().LowerBound(),
- RangeBoundary::NegativeInfinity());
- }
- if (!RangeBoundary::SymbolicAdd(left_max, right_range->max(), result_max)) {
- *result_max = RangeBoundary::Add(right_range->max().UpperBound(),
- left_range->max().UpperBound(),
- RangeBoundary::PositiveInfinity());
- }
-}
-
-
-void Range::Sub(const Range* left_range,
- const Range* right_range,
- RangeBoundary* result_min,
- RangeBoundary* result_max,
- Definition* left_defn) {
- ASSERT(left_range != NULL);
- ASSERT(right_range != NULL);
- ASSERT(result_min != NULL);
- ASSERT(result_max != NULL);
-
- RangeBoundary left_min =
- IsArrayLength(left_defn) ?
- RangeBoundary::FromDefinition(left_defn) : left_range->min();
-
- RangeBoundary left_max =
- IsArrayLength(left_defn) ?
- RangeBoundary::FromDefinition(left_defn) : left_range->max();
-
- if (!RangeBoundary::SymbolicSub(left_min, right_range->max(), result_min)) {
- *result_min = RangeBoundary::Sub(left_range->min().LowerBound(),
- right_range->max().UpperBound(),
- RangeBoundary::NegativeInfinity());
- }
- if (!RangeBoundary::SymbolicSub(left_max, right_range->min(), result_max)) {
- *result_max = RangeBoundary::Sub(left_range->max().UpperBound(),
- right_range->min().LowerBound(),
- RangeBoundary::PositiveInfinity());
- }
-}
-
-
-bool Range::Mul(const Range* left_range,
- const Range* right_range,
- RangeBoundary* result_min,
- RangeBoundary* result_max) {
- ASSERT(left_range != NULL);
- ASSERT(right_range != NULL);
- ASSERT(result_min != NULL);
- ASSERT(result_max != NULL);
-
- const int64_t left_max = ConstantAbsMax(left_range);
- const int64_t right_max = ConstantAbsMax(right_range);
- if ((left_max <= -kSmiMin) && (right_max <= -kSmiMin) &&
- ((left_max == 0) || (right_max <= kMaxInt64 / left_max))) {
- // Product of left and right max values stays in 64 bit range.
- const int64_t mul_max = left_max * right_max;
- if (Smi::IsValid(mul_max) && Smi::IsValid(-mul_max)) {
- const int64_t r_min =
- OnlyPositiveOrZero(*left_range, *right_range) ? 0 : -mul_max;
- *result_min = RangeBoundary::FromConstant(r_min);
- const int64_t r_max =
- OnlyNegativeOrZero(*left_range, *right_range) ? 0 : mul_max;
- *result_max = RangeBoundary::FromConstant(r_max);
- return true;
- }
- }
- return false;
-}
-
-
-// Both the a and b ranges are >= 0.
-bool Range::OnlyPositiveOrZero(const Range& a, const Range& b) {
- return a.OnlyGreaterThanOrEqualTo(0) && b.OnlyGreaterThanOrEqualTo(0);
-}
-
-
-// Both the a and b ranges are <= 0.
-bool Range::OnlyNegativeOrZero(const Range& a, const Range& b) {
- return a.OnlyLessThanOrEqualTo(0) && b.OnlyLessThanOrEqualTo(0);
-}
-
-
-// Return the maximum absolute value included in range.
-int64_t Range::ConstantAbsMax(const Range* range) {
- if (range == NULL) {
- return RangeBoundary::kMax;
- }
- const int64_t abs_min = Utils::Abs(Range::ConstantMin(range).ConstantValue());
- const int64_t abs_max = Utils::Abs(Range::ConstantMax(range).ConstantValue());
- return Utils::Maximum(abs_min, abs_max);
-}
-
-
-Range* Range::BinaryOp(const Token::Kind op,
- const Range* left_range,
- const Range* right_range,
- Definition* left_defn) {
- ASSERT(left_range != NULL);
- ASSERT(right_range != NULL);
-
- // Both left and right ranges are finite.
- ASSERT(left_range->IsFinite());
- ASSERT(right_range->IsFinite());
-
- RangeBoundary min;
- RangeBoundary max;
- ASSERT(min.IsUnknown() && max.IsUnknown());
-
- switch (op) {
- case Token::kADD:
- Range::Add(left_range, right_range, &min, &max, left_defn);
- break;
- case Token::kSUB:
- Range::Sub(left_range, right_range, &min, &max, left_defn);
- break;
- case Token::kMUL: {
- if (!Range::Mul(left_range, right_range, &min, &max)) {
- return NULL;
- }
- break;
- }
- case Token::kSHL: {
- Range::Shl(left_range, right_range, &min, &max);
- break;
- }
- case Token::kSHR: {
- Range::Shr(left_range, right_range, &min, &max);
- break;
- }
- case Token::kBIT_AND:
- if (!Range::And(left_range, right_range, &min, &max)) {
- return NULL;
- }
- break;
- default:
- return NULL;
- break;
- }
-
- ASSERT(!min.IsUnknown() && !max.IsUnknown());
-
- return new Range(min, max);
-}
-
-
bool CheckArrayBoundInstr::IsFixedLengthArrayType(intptr_t cid) {
return LoadFieldInstr::IsFixedLengthArrayCid(cid);
}
-bool CheckArrayBoundInstr::IsRedundant(RangeBoundary length) {
- Range* index_range = index()->definition()->range();
-
- // Range of the index is unknown can't decide if the check is redundant.
- if (index_range == NULL) {
- return false;
- }
-
- // Range of the index is not positive. Check can't be redundant.
- if (Range::ConstantMinSmi(index_range).ConstantValue() < 0) {
- return false;
- }
-
- RangeBoundary max = CanonicalizeBoundary(index_range->max(),
- RangeBoundary::PositiveInfinity());
-
- if (max.OverflowedSmi()) {
- return false;
- }
-
-
- RangeBoundary max_upper = max.UpperBound();
- RangeBoundary length_lower = length.LowerBound();
-
- if (max_upper.OverflowedSmi() || length_lower.OverflowedSmi()) {
- return false;
- }
-
- // Try to compare constant boundaries.
- if (max_upper.ConstantValue() < length_lower.ConstantValue()) {
- return true;
- }
-
- length = CanonicalizeBoundary(length, RangeBoundary::PositiveInfinity());
- if (length.OverflowedSmi()) {
- return false;
- }
-
- // Try symbolic comparison.
- do {
- if (DependOnSameSymbol(max, length)) return max.offset() < length.offset();
- } while (CanonicalizeMaxBoundary(&max) || CanonicalizeMinBoundary(&length));
-
- // Failed to prove that maximum is bounded with array length.
- return false;
-}
-
-
Instruction* CheckArrayBoundInstr::Canonicalize(FlowGraph* flow_graph) {
return IsRedundant(RangeBoundary::FromDefinition(length()->definition())) ?
NULL : this;
« no previous file with comments | « runtime/vm/intermediate_language.h ('k') | runtime/vm/intermediate_language_arm.cc » ('j') | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698