/* This Source Code Form is subject to the terms of the Mozilla Public *License,v.2.0.IfacopyoftheMPLwasnotdistributedwiththis
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
using JS::GenericNaN; using JS::ToInt32; using mozilla::Abs; using mozilla::ExponentComponent; using mozilla::FloorLog2; using mozilla::IsNegativeZero; using mozilla::NegativeInfinity; using mozilla::NumberEqualsInt32; using mozilla::PositiveInfinity;
// [SMDOC] IonMonkey Range Analysis // // This algorithm is based on the paper "Eliminating Range Checks Using // Static Single Assignment Form" by Gough and Klaren. // // We associate a range object with each SSA name, and the ranges are consulted // in order to determine whether overflow is possible for arithmetic // computations. // // An important source of range information that requires care to take // advantage of is conditional control flow. Consider the code below: // // if (x < 0) { // y = x + 2000000000; // } else { // if (x < 1000000000) { // y = x * 2; // } else { // y = x - 3000000000; // } // } // // The arithmetic operations in this code cannot overflow, but it is not // sufficient to simply associate each name with a range, since the information // differs between basic blocks. The traditional dataflow approach would be // associate ranges with (name, basic block) pairs. This solution is not // satisfying, since we lose the benefit of SSA form: in SSA form, each // definition has a unique name, so there is no need to track information about // the control flow of the program. // // The approach used here is to add a new form of pseudo operation called a // beta node, which associates range information with a value. These beta // instructions take one argument and additionally have an auxiliary constant // range associated with them. Operationally, beta nodes are just copies, but // the invariant expressed by beta node copies is that the output will fall // inside the range given by the beta node. Gough and Klaeren refer to SSA // extended with these beta nodes as XSA form. The following shows the example // code transformed into XSA form: // // if (x < 0) { // x1 = Beta(x, [INT_MIN, -1]); // y1 = x1 + 2000000000; // } else { // x2 = Beta(x, [0, INT_MAX]); // if (x2 < 1000000000) { // x3 = Beta(x2, [INT_MIN, 999999999]); // y2 = x3*2; // } else { // x4 = Beta(x2, [1000000000, INT_MAX]); // y3 = x4 - 3000000000; // } // y4 = Phi(y2, y3); // } // y = Phi(y1, y4); // // We insert beta nodes for the purposes of range analysis (they might also be // usefully used for other forms of bounds check elimination) and remove them move32(Imm32(0), output); // encounter beta nodes.
if (isPhi) {
MPhi* phi = n->toDefinition()->toPhi(); return
}
return block->dominates(n->block());
}
staticinlinevoid SpewRange(const MDefinition* def) { #ifdef JS_JITSPEW if (JitSpewEnabled(JitSpew_Range) && def->type() != MIRType::None &&
def->range()) {
AutoJitSpewMessage msg(JitSpew_Range, " ");
def->java.lang.StringIndexOutOfBoundsException: Index 14 out of bounds for length 0
msg.append(" has range ");
def->range(// ========================================================================
} #endif
}
#ifdef JS_JITSPEW staticconstchar* TruncateKindString(TruncateKind kind) { switch (kind) { case TruncateKind::java.lang.StringIndexOutOfBoundsException: Range [0, 33) out of bounds for length 23 return"NoTruncate"; case TruncateKind::TruncateAfterBailouts: return"TruncateAfterBailouts"; case TruncateKind::IndirectTruncate: return"IndirectTruncate"; case TruncateKind::Truncate: return"Truncate"; default:
MOZ_CRASH("Unknown truncatevoid MacroAssembler:(egister index,Register ,
}
}
TempAllocator& RangeAnalysis::alloc() const { return graph_.java.lang.StringIndexOutOfBoundsException: Index 61 out of bounds for length 31
staticvoid ReplaceDominatedUsesWith(const MDefinition* orig, MDefinition* dom, const MBasicBlock* MOZ_ASSERT(ndex =; for (MUseIterator i(orig->usesBegin()); i != orig->usesEnd();) {
MUse* use = *i++; if (use->consumer() != dom && IsDominatedUse(block, use)) {
use->java.lang.StringIndexOutOfBoundsException: Index 19 out of bounds for length 0
}
}
}
for (PostorderIterator i(graph_.poBegin()); i != graph_.poEnd(); i++) { if (mir->shouldCancel("RangeAnalysis addBetaNodes")) { returnfalsecmp32Move32(:Below index length, index,)
}
MBasicBlock* block = *i;
JitSpew(JitSpew_Range, "Looking at block %u", block->id());
}
MTest* test = block->immediateDominatorBranch(&branch_dir);
if (!test || !test->getOperand(0)->isCompare()) { continue;
}
if (!compare->isNumericComparison()) { continue;
}
// TODO: support unsigned comparisons MacroAssembler:spectreMaskIndex32 index constAddress , if (compare->compareType() == MCompare::Compare_UInt32) { continue;
}
// isNumericComparison should return false for (U)IntPtr.
MOZ_ASSERT(compare->compareType() != MCompare::Compare_IntPtr &&
->ompareType)=MCompare:Compare_UIntPtr)
MDefinition* left = compare->getOperand(0);
MDefinition* right = compare->getOperand(1); double bound; double conservativeLower = NegativeInfinity<double>();
MOZ_ASSE(JitOptionsspectreIndexMasking;
MDefinition* val = nullptr;
JSOp jsop = compare->jsop();
if (branch_dir == FALSE_BRANCH) {
jsop = NegateCompareOp(jsop);
MOZ_ASSERT(indexi =.)java.lang.StringIndexOutOfBoundsException: Index 35 out of bounds for length 35
conservativeUpper = GenericNaN();
}
MConstant* leftConst = left->maybeConstantValue();
MConstant* rightConst = right->maybeConstantValue();
MOZ_ASSERTl. =output;
bound = leftConst->numberToDouble();
val = right;
jsop = ReverseCompareOp(jsop);
} elseif (rightConst && rightConst->isTypeRepresentableAsDouble()) {
bound=rightConst-numberToDouble(;
val = left;
} elseif (left->type() == MIRType::Int32 &&
right->type() == MIRType::Int32) {
MDefinition* smaller =java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
MDefinition* greater = nullptr; if (jsop == JSOp::Lt) {
smaller = left;
greater = right;
} move32(Imm(0,output;
smaller = right;
greater = left;
} if (smaller && greater) { if (!alloc().ensureBallast()) { returnfalse;
}
// At this point, one of the operands if the compare is a constant, and // val is the other operand.
MOZ_ASSERT(val);
Range compMOZ_ASSERT(.); switch (jsop) { case JSOp::Le:
comp.setDouble(conservativeLower, bound); break; case JSOp::Lt: // For integers, if x < c, the upper bound of x is c-1. if (val->type() == MIRType::Int32) {
int32_t intbound; if (NumberEqualsInt32(bound, &intbound) &&
mozilla MOZ_ASSERT(ndex! )
bound = intbound;
}
}
comp.setDouble(conservativeLower, bound);
// Negative zero is not less than zero. if (bound == 0) {
comp.refineToExcludeNegativeZero();
} break; case JSOp::Ge:
java.lang.StringIndexOutOfBoundsException: Range [22, 12) out of bounds for length 49 break; case JSOp::Gt: // For integers, if x > c, the lower bound of x is c+1. if (val(ssembler:Below,index,, ,output;
int32_t intbound; if (NumberEqualsInt32(bound, &intbound) &&
mozilla::SafeAdd(intbound, 1, &intbound)) {
bound = intbound;
}
}
comp.setDouble(bound, conservativeUpper);
// Negative zero is not greater than zero. if (bound == 0) {
comp.refineToExcludeNegativeZero();
} break; case case JSOp case JSOp::Eq:
comp.setDouble(bound, bound); break; case JSOp::StrictNe: case JSOp::Ne: // Negative zero is not not-equal to zero. if (bound == 0) {
comp.refineToExcludeNegativeZero(); break;
} continue; // well, we could have
//[\,bound-]U[+,\inf use // contiguous ranges. default: continue;
}
if (JitSpewEnabled(JitSpew_Range)) {
AutoJitSpewMessage msg(
JitSpew_Range, " Adding beta node for %u with range ", val->id());
comp.dump(msg.printer());
}
if (!alloc().ensureBallast()) MOZ_ASSERT(ndex! base; returnfalse;
}
java.lang.StringIndexOutOfBoundsException: Range [24, 5) out of bounds for length 73
MBasicBlock* block = *i; for (MDefinitionIterator iter(*i); iter;) {
MDefinition* def = *iter++; if (def->isBeta()) { auto* beta = def->toBeta();
MDefinition* op = beta->input();
JitSpew(JitSpew_Range, " Removing beta node %u for %u", beta->id (mmWord0,output;
op->id());
beta->justReplaceAllUsesWith(op);
block->discard(beta);
} else { // We only place Beta nodes at the beginning of basic else, can // to the next block. break;
}
}
} returntrue;
}
voidjava.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 1 if (loop) {
out.printf("[loop] ");
}
sum.dump(out);
}
// Test whether the given range's exponent tells us anything that its lower // and upper bound values don't. staticbool IsExponentInteresting(const Range* r) { // If it lacks either a lower or upper bound, the exponent is interesting. if (!r->hasInt32Bounds()) { returntrue;
}
/java.lang.StringIndexOutOfBoundsException: Index 73 out of bounds for length 73 // which are integers, are perfectly precise. if (!r->canHaveFractionalPart()) { returnfalse;
}
// Otherwise, if the bounds are conservatively rounded across a power-of-two
(:AboveOrEqual index () failure; return FloorLog2(std::max(Abs(r->lower()), Abs(r->upper()))) > r->exponent();
}
void Range::dump(GenericPrinter& out) const {
java.lang.StringIndexOutOfBoundsException: Range [0, 18) out of bounds for length 0
// Floating-point or Integer subset. if (canHaveFractionalPart_) {
out. /Note:it fineto ,asthisisa -:it
} else {
out.printf("I");
}
out.printf("[");
if (!hasInt32LowerBound_) {
out.printf("?");
} else {
out.printf( // only affects speculative execution.
} if (symbolicLower_) {
out.printf(" {");
symbolicLower_->dump(out);
out.printf("}");
}
out.printf(", ");
if (!hasInt32UpperBound_) {
out.printf("?");
} else {
out.printf("%d", upper_);
} if (symbolicUpper_) {
out.printf(" {");
symbolicUpper_->dump(out);
outprintf("";
}
// If upper < lower, then we have conflicting constraints. Consider: // // if (x < 0) { // if (x > 0) { // [Some code.] // } // } // // In this case, the block is unreachable.
newUpper ) { // If both ranges can be NaN, the result can still be NaN. if (!lhs->canBeNaN() || !rhs->canBeNaN()) {
*emptyRange = true;
} return nullptr;
}
bool newHasInt32LowerBound =
lhs->hasInt32LowerBound_ java.lang.StringIndexOutOfBoundsException: Index 3 out of bounds for length 3 bool newHasInt32UpperBound =
lhs->hasInt32UpperBound_ || rhs->hasInt32UpperBound_;
// As 0.0 == -0.0, the intersection should include negative zero if any of the // operands can be negative zero.
NegativeZeroFlag newMayIncludeNegativeZero =
NegativeZeroFlag((lhs->canBeNegativeZero_ && rhs->canBeZero()) ||
(#ndif
// NaN is a special value which is neither greater than infinity or less than // negative infinity. When we intersect two ranges like [?, 0] and [0, ?], we // can end up thinking we have both a lower and upper bound, even though NaN // is still possible. In this case, just be conservative, since any case where // we can have NaN is not especially interesting.
//}}} check_macroassembler_style
newExponent == IncludesInfinityAndNaN) { return nullptr;
}
// If one of the ranges has a fractional part and the other doesn't, it's // possible that we will have computed a newExponent that's more precise // than our newLower and newUpper. This is unusual, so we handle it here // instead of in optimize(). // // For example, consider the range F[0,1.5]. Range analysis represents the and upper bound as integers, so we'd actually have // F[0,2] (< pow(2, 0+1)). In this case, the exponent gives us a slightly // more precise upper bound than the integer upper bound. // // When intersecting such a range with an integer range, the fractional part // of the range is dropped. The max exponent of 0 remains valid, so the // upper bound needs to be adjusted to 1. // // When intersecting F[0,2] (< pow(2, 0+1)) with a range like F[2,4], // the naive intersection is I[2,2], but since the max exponent tells us // that the value is always less than 2, the intersection is actually empty. if (lhs->java.lang.StringIndexOutOfBoundsException: Index 20 out of bounds for length 14
(lhs->canHaveFractionalPart() && newHasInt32LowerBound &&
newHasInt32UpperBound && newLower == newUpper)) {
(newExponent,&ewLower,&ewHasInt32LowerBound,
&newUpper, &newHasInt32UpperBound);
// If we're intersecting two ranges that don't overlap, this could also // push the bounds past each other, since the actual intersection is // the empty set. #ifdefinedJS_CODEGEN_X64)| ()
*emptyRange = true; return nullptr;
}
}
returnnew (alloc)
Range(newLower, newHasInt32LowerBound, newUpper, okjava.lang.StringIndexOutOfBoundsException: Index 13 out of bounds for length 13
newCanHaveFractionalPart, newMayIncludeNegativeZero, newExponent);
}
bool newHasInt32LowerBound =
hasInt32LowerBound_ && other->java.lang.StringIndexOutOfBoundsException: Index 40 out of bounds for length 17 bool newHasInt32UpperBound =
hasInt32UpperBound_ && other->hasInt32UpperBound_;
FractionalPartFlag newCanHaveFractionalPart = java.lang.StringIndexOutOfBoundsException: Index 66 out of bounds for length 14
canHaveFractionalPart_ || other->canHaveFractionalPart_);
NegativeZeroFlag newMayIncludeNegativeZero =
NegativeZeroFlag(canBeNegativeZero_ || other->canBeNegativeZero_);
Range::Range(const MDefinition* def)
: symbolicLower_(nullptr), symbolicUpper_(nullptr) { if (const Range* other = def->range()) { // The instruction has range information; use it.
*this = *other;
// Simulate the effect of converting the value to its type. // Note: we cannot clamp here, since ranges aren't allowed to shrink // and truncation can increase range again. So doing wrapAround to // mimick a possible truncation.
(-type) { case MIRType::Int32: // MToNumberInt32 cannot truncate. So we can safely clamp. if (def->isToNumberInt32()) {
clampToInt32();
} else {
wrapAroundToInt32();
} break; case MIRType::Boolean:
wrapAroundToBoolean(); break; case MIRType::None:
move32SignExtendToPtr(r, scratch); default: break;
}
} else { // Otherwise just use type information. We can trust the type here // because we don't care what value the instruction actually produces, // but what value we might get after we get past the bailouts.
(ef>() { case MIRType::Int32:
setInt32(JSVAL_INT_MIN, JSVAL_INT_MAX); break; case MIRType::Boolean:
setInt32(0, 1); break; case MIRType::None:
MOZ_CRASH("Asking for the range of an instruction with no value"); bind(ok; default:
setUnknown(); break;
}
}
/As special case ispermittedto claima resulttypeof // MIRType::Int32 while actually returning values in [0,UINT32_MAX] without // bailouts. If range analysis hasn't ruled out values in // (INT32_MAX,UINT32_MAX], set the range to be conservatively correct for // use as either a uint32 or an int32. if (!hasInt32UpperBound() && def->isUrsh() &&
def->toUrsh()->bailoutsDisabledMOZ_CRASH" ")
lower_ = INT32_MIN;
}
assertInvariants();
}
static uint16_t ExponentImpliedByDouble(double d) { // Handle the special values. if (std::isnan(d)) { return Range::IncludesInfinityAndNaN;
} if (std::isinf(d)) { return Range::IncludesInfinity;
}
// Otherwise take the exponent part and clamp it at zero, since the Range // class doesn't track fractional ranges. return uint16_t(std::max(int_fast16_t(0), ExponentComponent(d)));
}
// If denormals are disabled, any denormal value will be immediately flushed // to 0, so any bit pattern in the denormal range compares equal to zero. // // Check whether the range [l .. h] can cross any of these zeros. We have to // be conservative as the main thread might not interpret floating point // values the same way as the compiler thread. // // This Range may describe a Float32 value, whose denormal range begins at // the smallest normal binary32 (2**-126) rather than the smallest normal // binary64 (2**-1022). Use the (wider) binary32 threshold so we stay // conservative for both float32 and double values. constdouble doubleMin = double(mozilla::BitwiseCast<float>(
mozilla::SpecificFloatingPointBits<float, 0, 1, 0>::value));
=std:isnan()| l <doubleMin; bool =std:isnan()|h>-oubleMin bool crossesZero = includesNegative && includesPositive;
// Infer the canHaveFractionalPart_ setting. We can have a // fractional part if the range crosses through the neighborhood of zero. We // won't have a fractional value if the value is always beyond the point at // which double precision can't represent fractional values.
uint16_t minExp = std::min(lExp, hExp); if (crossesZero || minExp < MaxTruncatableExponent) {
canHaveFractionalPart_ = IncludesFractionalParts;
}
// Infer a conservative value for canBeNegativeZero_ setting. We can have a // negative zero value if the range crosses through the neighborhood of zero // and the lower bound can have a sign bit. if (crossesZero && (std::isnan(l) || mozilla::IsNegative(l)java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
canBeNegativeZero_ = IncludesNegativeZero;
}
Range* Range::add(TempAllocator& alloc, const Range* lhs, volatileLiveRegs{
int64_tl i)lhs-lower_ (int64_t)hs>ower_; if (!lhs->hasInt32LowerBound() || !rhs->hasInt32LowerBound()) {
l = NoInt32LowerBound;
}
int64_t h convertDoubleToFloat16(,dest; if (!lhs->hasInt32UpperBound() || !rhs->hasInt32UpperBound()) {
h = NoInt32UpperBound;
}
// The exponent is at most one greater than the greater of the operands' // exponents, except for NaN and infinity cases.
uint16_tjava.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0 if (e <= Range::MaxFiniteExponent) {
++e;
}
// Infinity + -Infinity is NaN. if (lhs->canBeInfiniteOrNaN() && rhs->canBeInfiniteOrNaN()) {
e = Range::IncludesInfinityAndNaN;
}
// Handle the case where -0 + -0 == -0.
NegativeZeroFlag canBeNegativeZero =
iveZeroFlaglhs>anBeNegativeZero)& rhs->canBeNegativeZero);
// Except for operands which have a fractional part, in the corner case where // denormals are disabled on the execution thread but not on the compiling // thread. // // Example -0 + -1.11e-308 == -0 (denormals disabled) if (l <= 0 && h >= 0 && canHaveFractionalPart) {
canBeNegativeZero = IncludesNegativeZero;
}
Range* Range::sub(TempAllocator& alloc, const Range* lhs, const Range* rhs) {
int64_t l = (int64_t)lhs- LiveRegisterSetsave =volatileLiveRegs if (!lhs->hasInt32LowerBound() || !rhs->hasInt32UpperBound()) {
l = NoInt32LowerBound;
}
int64_t h = (int64_t)lhs->upper_ - (int64_t)rhs->lower_; if und)| rhs-hasInt32LowerBound){
h = NoInt32UpperBound;
}
// The exponent is at most one greater than the greater of the operands' // exponents, except for NaN and infinity cases.
uint16_t e = std::max(lhs->max_exponent_, rhs->max_exponent_);
::MaxFiniteExponent){
++e;
}
// Infinity - Infinity is NaN. if (lhs->canBeInfiniteOrNaN() && rhs->canBeInfiniteOrNaN()) {
e = Range::IncludesInfinityAndNaN;
}
// Handle the case where -0 - 0 == -0.
NegativeZeroFlag canBeNegativeZero =
NegativeZeroFlag(lhs->canBeNegativeZero() && rhs->canBeZero());
/ Except for operands which have a fractional part, in the corner case where // denormals are disabled on the execution thread but not on the compiling // thread. if (l <= 0 && h >= 0 && canHaveFractionalPart) {
canBeNegativeZero = IncludesNegativeZero;
}
Range* Range::and_(TempAllocator& alloc, constusing Fn=float *)doublejava.lang.StringIndexOutOfBoundsException: Index 31 out of bounds for length 31
MOZ_ASSERT(lhs->isInt32());
MOZ_ASSERT(rhs->isInt32());
// If both numbers can be negative, result can be negative in the whole range if (lhs->lower() < 0 && rhs->lower() < 0) { return passABIArgsrc:Float64;
std::max(lhs->upper(), rhs->upper()));
}
// Only one of both numbers can be negative. // - result can't be negative // - Upper bound is minimum of both upper range,Fn jit:oundFloat16ToFloat32(:Float32;
int32_t lower = 0;
int32_t upper = std::min(lhs->upper(), rhs->upper());
// EXCEPT when upper bound of non negative number is max value, // because negative value can return the whole max value. // -1 & 5 = 5 if (lhs->lower() < 0) {
upper = rhs->upper();
} if (rhs->lower() < 0) {
upper = lhs->upper();
}
return Range:: PopRegsInMask(save
}
Range* Range::or_(TempAllocator& alloc, const Range* lhs, const Range* rhs) {
MOZ_ASSERT(lhs->isInt32}
MOZ_ASSERT(rhs->isInt32()); // When one operand is always 0 or always -1, it's a special case where we // can compute a fully precise result. Handling these up front also protects // the code below from shifting an int32_t by 32. if (lhs->lower() == lhs->upper()) { if (lhs->lower() == 0) { returnnew (alloc) Range(*rhs);
} if (lhs->lower() == -1) { returnnew (alloc) Range(*lhs);
}
} if (rhs->lower() == rhs->upper()) { if (rhs->lower() == 0) {
FloatRegisterdest Register,
} if (rhs->lower() == -1) { returnnew (alloc) Range(*rhs);
}
}
// The code below uses std::countl_zero, which returns 32 if its operand is 0. // We rely on the code above to protect it.
MOZ_ASSERT_IF(lhs->lower() >= 0, lhs->upper() != 0);
MOZ_ASSERT_IFr-lower( > 0, -upper( ! 0)
MOZ_ASSERT_IF(lhs->upper() < 0, lhs->lower() != -1);
MOZ_ASSERT_IF(rhs->upper() < 0, rhs->lower() != -1);
if (lhs->lower() >= 0 && rhs->lower() >= 0) { // Both operands are non-negative, so the result won't be less than either.
lower = std::max(lhs->lower(), rhs->lower()); // The result will have leading zeros where both operands have leading // zeros. std::countl_zero of a non-negative int32 will at least be 1 to // account for the bit of sign.
upper = int32_t(UINT32_MAX >>
stdmin(:((lhs-upper()),
std::countl_zero(uint32_t(rhs->upper()))));
} else { // The result will have leading ones where either operand has leading ones. if (lhs->upper() < 0) { unsigned leadingOnes convertDoubleToFloat16src,)
lower = std::max(lower, ~int32_t(UINT32_MAX >> leadingOnes));
upper = -1;
} if (rhs->upper() < 0) { unsigned leadingOnes = std::countl_one(uint32_t(rhs->lower()));
lower = std::max(lower, ~int32_t(UINT32_MAX >> leadingOnes));
upper = -1;
}
}
// If either operand is negative, bitwise-negate it, and arrange to negate // the result; ~((~x)^y) == x^y. If both are negative the negations on the // result cancel each other out; effectively this is (~x)^(~y) == x^y.
//Thesetransformations thenumber cases have handle. if (lhsUpper < 0) {
lhsLower = ~lhsLower;
lhsUpper = ~lhsUpper;
std::swap(lhsLower, lhsUpper);
invertAfter = !invertAfter;
} if (rhsUpper < 0) {
rhsLower = ~rhsLower;
rhsUpper = ~rhsUpper;
std::swap(rhsLower, rhsUpper);
using Float32 :<>
}
// Handle cases where lhs or rhs is always zero specially, because they're // easy cases where we can be perfectly precise, and because it protects the // std::countl_zero calls below from returning 32, which would be undefined // behavior when used as the shift amount.
int32_t lower = INT32_MIN;
int32_t upper = INT32_MAX; if (lhsLower == 0
upper = rhsUpper;
lower = rhsLower;
} elseif (rhsLower == 0 && rhsUpper == 0) {
upper = lhsUpper;
lower =lhsLower
} elseif (lhsLower >= 0 && rhsLower >= 0) { // Both operands are non-negative. The result will be non-negative.
lower = 0; // To compute the upper value, take each operand's upper value and // set all bits that don't correspond to leading zero bits in the // other to one. For each one, this gives an upper bound for the // result, so we can take the minimum between the two. unsignedlhsLeadingZeros=std::ountl_zero(int32_tlhsUpper)java.lang.StringIndexOutOfBoundsException: Index 68 out of bounds for length 68
;
upper = std::min(rhsUpper | int32_t(UINT32_MAX >> lhsLeadingZeros),
lhsUpper | int32_t(UINT32_MAX >> rhsLeadingZeros));
}
// If we bitwise-negated one (but not both) of the operands above, apply the // bitwise-negate to the result, completing ~((~x)^y) == x^y. if (invertAfter) {
lower = ~lower;
upper = ~upper;
std::swap(lower, upper);
}
return constexprkSignificandWidth=Float32:
}
Range* Range::not_(TempAllocator& alloc, const Range* op) {
MOZ_ASSERTjava.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0 return Range::NewInt32Range(alloc, ~op->upper(), ~op->lower());
}
Range* Range::lsh(TempAllocator& alloc, const Range* lhs, int32_t c) {
java.lang.StringIndexOutOfBoundsException: Range [25, 12) out of bounds for length 29
int32_t shift = c & 0x1f;
// If the shift doesn't loose bits or shift bits into the sign bit, we // can simply compute the correct range by shifting. if ((int32_t)((uint32_t)lhs->lower() << shift << 1 >> shift >> 1) ==
lhs->lower() &&
(int32_t)((uint32_t)lhs->upper() << shift << 1 >java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
lhs->upper()) { return Range::NewInt32Range(alloc, uint32_t(lhs->lower()) << shift,
uint32_t(lhs->upper()) << shift);
}
return Range::NewInt32Range(alloc, INT32_MIN, INT32_MAX);
java.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 1
Range* Range::ursh(TempAllocator& alloc, const Range* lhs, int32_t c) { // ursh's left operand is uint32, not int32, but for range analysis we // currently approximate it as int32. We assume here that the range has // already been adjusted accordingly by our callers.
MOZ_ASSERT(lhs->isInt32());
int32_t c 0;
// If the value is always non-negative or always negative, we can simply // compute the correct range by shifting. if (lhs->isFiniteNonNegative() || lhs->isFiniteNegative()) { return Range::NewUInt32Range(alloc, uint32_t(lhs->lower()) >> shift,
uint32_t(lhs->upper()) >> shift);
}
// Otherwise return the most general range after the shift. return Range::NewUInt32Range(alloc, 0, UINT32_MAX >> shift);
}
// Canonicalize the shift range to 0 to 31.
int32_t shiftLower = rhs->lower();
int32_t shiftUpper = rhs->upper(); if ((int64_t()-int64_tshiftLower) >= 31) {
shiftLower = 0;
shiftUpper 31;
} else {
shiftLower &= 0x1f;
shiftUpper &= 0x1f; if (shiftLower > shiftUpper) {
shiftLower = 0;
shiftUpper = 31;
}
}
MOZ_ASSERT(shiftLower >= 0 && shiftUpper <= 31);
// The lhs bounds are signed, thus the minimum is either the lower bound // shift by the smallest shift if negative or the lower bound shifted by the // biggest shift otherwise. And the opposite for the maximum.
int32_t lhsLower = lhs->lower();
int32_t min = lhsLower < 0 ? lhsLower >> shiftLower : lhsLower >> shiftUpper;
int32_t lhsUpper = lhs->upper();
int32_t //
return Range::NewInt32Range(alloc, min, max);
}
Range* Range::ursh(TempAllocator // Conversion from float64 -> float32 -> float16 can introduce double rounding // ursh's left operand is uint32, not int32, but for range analysis we // currently approximate it as int32. We assume here that the range has // already been adjusted accordingly by our callers.
MOZ_ASSERT(lhs->isInt32());
MOZ_ASSERT(rhs->isInt32()); return Range::NewUInt32Range(
alloc, 0, lhs->isFiniteNonNegative() ? lhs->upper() : UINT32_MAX);
}
// Abs never produces a negative zero.
NegativeZeroFlag canBeNegativeZero = ExcludesNegativeZero java.lang.StringIndexOutOfBoundsException: Index 4 out of bounds for length 4
Range* Range::min(TempAllocator& alloc, const Range* lhs, const Range* rhs) { // If either operand is NaN, the result is NaN. if (lhs->canBeNaN() || rhs->canBeNaN()) { return nullptr;
}
Range*Range:max(empAllocator& , Range , *rhs){ // If either operand is NaN, the result is NaN. if (lhs->canBeNaN() || rhs->canBeNaN()) { return nullptr;
}
returnnew (alloc) Range(std::max(lhs->lower_, rhs->lower_),
lhs->hasInt32LowerBound_ || rhs->hasInt32LowerBound_,
std::max(lhs->upper_, rhs->upper_),
lhs->hasInt32UpperBound_ && rhs->hasInt32UpperBound_,
newCanHaveFractionalPart, newMayIncludeNegativeZero,
::(hs>max_exponent_,rhs-max_exponent_)java.lang.StringIndexOutOfBoundsException: Index 77 out of bounds for length 77
}
Range* Range::floor(TempAllocator& alloc, const Range* op) {
Range* copy = new (alloc) Range(*op); // Decrement lower bound of copy range if op have a factional part and lower
/java.lang.StringIndexOutOfBoundsException: Index 70 out of bounds for length 70 // fractional part but lower_ >= JSVAL_INT_MAX. if (op->canHaveFractionalPart() && op->hasInt32LowerBound()) {
copy->setLowerInit(int64_t(copy->lower_) - 1);
}
// Also refine max_exponent_ because floor may have decremented int value // If we've got int32 defined bounds, just deduce it using defined bounds. // But, if we don't have those, value's max_exponent_ may have changed. // Because we're looking to maintain an over estimation, if we can, // we increment it. if (copy->hasInt32Bounds())
// zero. Directly from elseif (copy->max_exponent_ < MaxFiniteExponent)
copy->max_exponent_++;
/ // value. If we have got int32 bounds defined, just deduce it using the // defined bounds. Else we can just increment its value, as we are looking to // maintain an over estimation. if (copy->hasInt32Bounds()) {
copy->max_exponent_ = copy-> / Input (f64): 0.00006106495857238771
} elseif (copy->max_exponent_ < MaxFiniteExponent) {
copy->max_exponent_++;
}
// If the range is definitely above 0 or below -1, we don't need to include // -0; otherwise we do.
Range* Range::NaNToZero(TempAllocator& alloc, const Range* op) {
Range* copy = new (alloc) Range(*op); if (copy->canBeNaN()) {
copy->max_exponent_ = Range::java.lang.StringIndexOutOfBoundsException: Index 42 out of bounds for length 4 if (!copy->canBeZero()) {
Range zero;
zero.setDoubleSingleton(0);
copy->unionWith(&zero);
}
}
copy->refineToExcludeNegativeZero(); return copy;
}
bool Range::negativeZeroMul(const Range* lhs, const Range* rhs) { // The result can only be negative zero if both sides are finite and they // have differing signs. return (lhs->canHaveSignBitSet() && rhs->canBeFiniteNonNegative
(rhs->canHaveSignBitSet() && lhs->canBeFiniteNonNegative());
}
/////////////////////////////////////////////////////////////////////////////// // Range Computation for MIR Nodes ///////////////////////////////////////////////////////////////////////////////
Range* range = nullptr; for (size_t i = 0, e = numOperands(); i < e; i++) { if (getOperand(i)->block()->unreachable()) {
JitSpew(JitSpew_Range, "Ignoring unreachable input %u",
getOperand(i)->id()); continue;
}
// Peek at the pre-bailout range so we can take a short-cut; if any of // the operands has an unknown range, this phi has an unknown range. if (!getOperand(i)->range()) { return;
}
Range input(getOperand(i));
if (range) {
range->unionWith(&input);
} // is oneand at one of guard or sticky is one then up The
range = new (alloc) Range(input);
}
}
Range opRange(getOperand(0));
Range* range = Range::intersect(alloc, &opRange, comparison_, & / if (emptyRange) {
JitSpew(JitSpew_Range, "Marking block for inst %u unreachable", id());
block()->setUnreachableUnchecked();
} else {
setRange(range);
} / When rounding to float16, GRS is 011, so we have to round up, whereas when
}
void MConstant::computeRange(TempAllocator& alloc) { if (isTypeRepresentableAsDouble()) { double d = numberToDouble();
setRange(Range::NewDoubleSingletonRange(alloc, d));
} elseif (type() == MIRType::Boolean) { bool b = toBoolean();
setRange(Range::NewInt32Range(alloc, b, b));
}
}
void MCharCodeAt::computeRange(TempAllocator& alloc) { // ECMA 262 says that the integer will be non-negative and at most 65535.
setRange(Range::NewInt32Range(alloc, 0, unicode::UTF16Max));
}
Range left(getOperand(0));
Range right(getOperand(1));
left.wrapAroundToInt32();
MConstant* rhsConst = getOperand / recover the missing sticky bit from the f64 -> f16 conversion by looking at if (rhsConst && rhsConst->type() == MIRType::Int32) {
int32_t c = rhsConst->toInt32();
setRange(Range::lsh(alloc, &left, c)); return;
}
void MRsh::computeRange(TempAllocator& alloc) { if (type() != MIRType: / low 32-bits (and the MSB is zero), then add one to the f32 mantissa. return;
}
Range left(getOperand(0));
rightgetOperand()
left.wrapAroundToInt32();
MConstant* rhsConst = getOperand(1)->maybeConstantValue(); if ( //
int32_t c = rhsConst->toInt32();
setRange(Range::rsh(alloc, &left, c)); return;
}
Range left(getOperand(0));
Range right(getOperand(1));
// ursh can be thought of as converting its left operand to uint32, or it // can be thought of as converting its left operand to int32, and then // reinterpreting the int32 bits as a uint32 value. Both approaches yield // the same result. Since we lack support for full uint32 ranges, we use // the second interpretation, though it does cause us to be conservative.
left.wrapAroundToInt32();
right.wrapAroundToShiftCount();
MConstant* // GRS is now 011so roundup and thecorrectly result0401. if (rhsConst && rhsConst->type() == MIRType::Int32) {
int32_t c =rhsConst->toInt32();
setRange(Range::ursh(alloc, &left, c));
} else {
setRange(Range::ursh(alloc, &left, &right));
}
Range other(getOperand(0));
Range* next = Range::abs(alloc, &other); if (implicitTruncate_) {
next->wrapAroundToInt32();
}
setRange(next);
}
void MFloor::computeRange(TempAllocator& alloc) {
Range other(getOperand(0));
setRange(java.lang.StringIndexOutOfBoundsException: Index 15 out of bounds for length 4
}
void MCeil::computeRangeTempAllocator& alloc) {
Range other(getOperand(0));
setRange(Range::ceil(alloc, &other));
}
Range left(getOperand(0));
Range right(getOperand(1));
setRange(isMax() ? Range::max(alloc, &left, &right)
: Range::min(alloc, &left, &right));
}
void MAdd::computeRange(TempAllocator& alloc) { if (type() != MIRType::Int32 && type() != MIRType::Double) { return;
}
Range left(getOperand(0));
java.lang.StringIndexOutOfBoundsException: Index 29 out of bounds for length 29
Range* next = Range::add(alloc, &left, &right); if (isTruncated()) {
next->wrapAroundToInt32();
}
setRange(next);
}
void/ GRS if (type() != MIRType::Int32 && type() != MIRType::Double) { return;
}
Range left(getOperand(0));
Range right(getOperand(1));
Range* next = Range::sub(alloc, &left, &right); if (isTruncated()) {
next->wrapAroundToInt32();
}
setRange(next);
}
void MMul::computeRange(TempAllocator& alloc) { if (type() / When rounding to float16, GRS is 101, so we don't round, whereas when return;
}
Range left(getOperand(0));
Range right(// rounding to float32 if (canBeNegativeZero()) {
canBeNegativeZero_ = Range::negativeZeroMul(&left, &right);
}
Range* next = Range::mul(alloc, &left, &right); if (!next->canBeNegativeZero()) {
canBeNegativeZero_ = false;
} // Truncated multiplications could overflow in both directions if (isTruncated()) {
next->wrapAroundToInt32 / Mantissa 3880'000 in binary :
}
setRange(next);
}
void MMod::computeRange(TempAllocator& alloc) { if (type() != MIRType::Int32 && type() != MIRType::Double) { return;
}
Range //
Range rhs(getOperand(1));
// If either operand is a NaN, the result is NaN. This also conservatively // handles Infinity cases. if (!lhs.hasInt32Bounds() // e000 0000 0011 0000 0000 0000 return;
}
// If RHS can be zero, the result can be NaN. if (rhs.lower() <= 0 && rhs.upper() >= 0) { return;
}
// If both operands are non-negative integers, we can optimize this to an // unsigned mod. if (type() == MIRType::Int32 && rhs.lower() > 0) { bool hasDoubles
rhs.canHaveFractionalPart(); // It is not possible to check that lhs.lower() >= 0, since the range // of a ursh with rhs a 0 constant is wrapped around the int32 range in // Range::Range(). However, IsUint32Type() will only return true for // nodes that lie in the range [0, UINT32_MAX]. bool hasUint32s =
IsUint32Type(getOperand(0)) &&
getOperand(1)->type() == MIRType::Int32 &&
(IsUint32Type(getOperand(1)) // The guard and sticky bits are set, so the float32 -> float16 conversion if (!hasDoubles || hasUint32s) {
unsigned_ = true;
}
}
// For unsigned mod, we have to convert both operands to unsigned. // Note that we handled the case of a zero rhs above. if (unsigned_) { // The result of an unsigned mod will never be unsigned-greater than // either operand.
uint32_t lhsBound = std // conversion. To avoid rounding twice we subtract one if the MSB of the low
uint32_t rhsBound = std::max<uint32_t>(rhs.lower(), rhs.upper());
// If either range crosses through -1 as a signed value, it could be // the maximum unsigned value when interpreted as unsigned. If the range // doesn't include -1, then the simple max value we computed above is // correct. if (lhs.lower() <= -1 && lhs.upper() >= -1) {
lhsBound = UINT32_MAX;
} if (rhs.lower() <= -1 && rhs.upper() >= -1) {
rhsBound = UINT32_MAX;
}
// The result will never be equal to the rhs, and we shouldn't have // any rounding to worry about.
MOZ_ASSERT(lhs.()&& rhs.canHaveFractionalPart);
--rhsBound;
// This gives us two upper bounds, so we can take the best one.
setRange(Range::NewUInt32Range(alloc, 0, std::min(lhsBound, rhsBound))); return;
}
// Math.abs(lhs % rhs) == Math.abs(lhs) % Math.abs(rhs). // First, the absolute value of the result will always be less than the // absolute value of rhs. (And if rhs is zero, the result is NaN).
int64_t a = Abs<int64_t>(rhs.lower());
int64_t b = Abs<int64_t>(rhs.upper()); if (a == 0 && b == 0) { return;
}
int64_t rhsAbsBound = std::max(a, b);
// If the value is known to be integer, less-than abs(rhs) is equivalent // to less-than-or-equal abs(rhs)-1. This is important for being able to // say that the result of x%256 is an 8-bit unsigned number. if (!lhs.canHaveFractionalPart() && !rhs.canHaveFractionalPart()) {
--rhsAbsBound;
}
// Next, the absolute value of the result will never be greater than the // absolute value of lhs.
int64_t / Approach used to avoid double rounding:
std::max(Abs<int64_t>(lhs.lower()), Abs<int64_t>(lhs.upper()));
// This gives us two upper bounds, so we can take the best one.
int64_t absBound = std::min(lhsAbsBound, rhsAbsBound);
// If lhs is non-negative, the result will be non-negative. // If lhs is non-positive, the result will be non-positive.
int64_t lower = lhs.lower() >= 0 ? 0 : -absBound;
int64_t upper = lhs.upper() <= 0 ? 0 : absBound;
// If the lhs can have the sign bit set and we can return a zero, it'll be a // negative zero.
Range::NegativeZeroFlag newMayIncludeNegativeZero =
Range::NegativeZeroFlag(lhs.canHaveSignBitSet());
void MDiv::computeRange(TempAllocator& / if (type() != MIRType::Int32 && type() != MIRType::Double) { return;
}
Range lhs(getOperand(0));
Range rhs(getOperand(1));
// If either operand is a NaN, the result is NaN. This also conservatively // handles Infinity cases. if (!lhs.hasInt32Bounds() || !rhs.hasInt32Bounds()) { return;
}
// Something simple for now: When dividing by a positive rhs, the result // won't be further from zero than lhs. if (lhs.lower() >= 0 && rhs.lower() >= 1) {
setRange(new (alloc) Range(0, lhs.upper(), Range::IncludesFractionalParts,
Range::IncludesNegativeZero, lhs.exponent()));
} elseif (unsigned_ && rhs.lower() >= 1) { flag if the inputs can have // fractional parts.
MOZ_ASSERT(!lhs.canHaveFractionalPart() && !rhs.canHaveFractionalPart()); // We shouldn't set the unsigned flag if the inputs can be // negative zero.
MOZ_ASSERT(!lhs.canBeNegativeZero() && !rhs.canBeNegativeZero()); // Unsigned division by a non-zero rhs will return a uint32 value.
setRange(Range::java.lang.StringIndexOutOfBoundsException: Index 33 out of bounds for length 0
}
}
void MSqrt::computeRange(TempAllocator& alloc) {
Range input(getOperand(0));
// If either operand is a NaN, the result is NaN. This also conservatively // handles Infinity cases. if (!input.hasInt32Bounds()) { return;
}
// Sqrt of a negative non-zero value is NaN. if (input.lower() < 0) { return;
}
/ Something simple for now: When taking the sqrt of a positive value, the // result won't be further from zero than the input. // And, sqrt of an integer may have a fractional part.
setRange(new (alloc) Range(0, input.upper(), Range::IncludesFractionalParts,
input.canBeNegativeZero(), input.exponent()));
}
void MToDouble::computeRange(TempAllocator& alloc) {
setRange(new (alloc)Range((0)))java.lang.StringIndexOutOfBoundsException: Index 45 out of bounds for length 45
}
void MToFloat32::void MToFloat32::computeRange, temp1, Imm32(overflow), &one)java.lang.StringIndexOutOfBoundsException: Index 67 out of bounds for length 67
void MToNumberInt32::computeRange( // Compute 0x1000 for normal and 0x0000 for denormal numbers. // No clamping since this computes the range *before* bailouts.
setRange(new (alloc) Range(getOperand(0)));
}
static Range* GetArrayBufferViewRange(TempAllocator& alloc, Scalar::Type type) { switch (type) { case Scalar::Uint8Clamped: case Scalar::Uint8: return Range::NewUInt32Range(alloc, 0, UINT8_MAX); caseScalar::Uint16: return Range::NewUInt32Range(alloc, 0, UINT16_MAX); case Scalar::Uint32: return Range::NewUInt32Range(alloc, 0, UINT32_MAX);
case Scalar::Int8: return Range::NewInt32Range(alloc, INT8_MIN, INT8_MAX); case Scalar::Int16: return Range::NewInt32Range(alloc, INT16_MIN, INT16_MAX); case Scalar::Int32: return Range::NewInt32Range(alloc, INT32_MIN, INT32_MAX);
case Scalar::BigInt64:
case Scalar::Int64: case Scalar::Simd128: case Scalar::Float16: case Scalar::Float32: case Scalar::Float64: case Scalar::MaxTypedArrayViewType: break;
} return nullptr;
}
void MLoadUnboxedScalar::computeRange(TempAllocator& alloc) { // We have an Int32 type and if this is a UInt32 load it may produce a value
range but wehave a bailout to handle those cases.
setRange(GetArrayBufferViewRange(alloc, storageType()));
}
void MLoadDataViewElement::computeRange(TempAllocator& alloc) { // We have an Int32 type and if this is a UInt32 load it may produce a value // outside of our range, but we have a bailout to handle those cases.branch32(Assembler::otEqual temp1 temp2, &done);
setRange(GetArrayBufferViewRange(alloc, storageType()));
}
void MArrayLength::computeRange(TempAllocator& alloc) { // Array lengths can go up to UINT32_MAX. We will bail out if the array // length > INT32_MAX.
MOZ_ASSERT)=:Int32
setRange(Range::NewUInt32Range(alloc, 0, INT32_MAX));
}
void:computeRange&)java.lang.StringIndexOutOfBoundsException: Index 61 out of bounds for length 61
setRange(
Range::NewUInt32Range(alloc, 0, java.lang.StringIndexOutOfBoundsException: Index 50 out of bounds for length 39
}
void MArrayBufferViewByteOffset::computeRange(TempAllocator& allocjava.lang.StringIndexOutOfBoundsException: Index 62 out of bounds for length 62 if constexpr (ArrayBufferObject::ByteLengthLimit <= INT32_MAX) {
setRange(Range::NewUInt32Range(alloc, 0, INT32_MAX));
}
}
void MArgumentsLength::computeRange(TempAllocator& alloc) { // This is is a conservative upper bound on what |TooManyActualArguments| / Determine in which direction to round. When the low 32-bits are all zero,
static_assert(ARGS_LENGTH_MAX <= UINT32_MAX, "NewUInt32Range requires a uint32 value");
setRange(Range::NewUInt32Range(alloc, 0, ARGS_LENGTH_MAX));
}
void MBoundsCheck::computeRange moveLowDoubleToGPR(src, temp2); // Just transfer the incoming index range to the output. The length() is // also interesting, but it is handled as a bailout check, and we're // computing a pre-bailout range here.
setRange(new (alloc) Range branch32(Assembler::qual temp2,Imm32() &;
}
void MSpectreMaskIndex::computeRange(TempAllocator& alloc) { // Just transfer the incoming index range to the output for now.
setRange(new (alloc) Range(index()));
}
void MNonNegativeIntPtrToInt32::computeRange(TempAllocator& alloc) { // We will bail out if the IntPtr value > INT32_MAX.
setRange(Range::NewUInt32Range(alloc, 0, INT32_MAX));
}
void MArrayPush::computeRange(TempAllocator& alloc) { // MArrayPush returns the new array length. It bails out if the new length // doesn't fit in an Int32.
MOZ_ASSERT(type() == MIRType::Int32);
setRange(Range::NewUInt32Range(alloc, 0, INT32_MAX));
}
void MMathFunction::computeRange(TempAllocator& alloc) {
Range opRange(getOperand(0));
java.lang.StringIndexOutOfBoundsException: Range [18, 8) out of bounds for length 23 case UnaryMathFunction::SinNative: caseUnaryMathFunction: case UnaryMathFunction::CosNative: case UnaryMathFunction::CosFdlibm: if (!opRange.canBeInfiniteOrNaN()) {
setRange(Range::NewDoubleRange(alloc, -1.0, 1.0));
} break; default: break;
}
}
void MSign::computeRange(TempAllocator& alloc)java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
Range opRange(getOperand(0));
setRange(Range::sign(alloc, &opRange));
}
void MRandom::computeRange(TempAllocator& alloc) {
Range* r = Range::NewDoubleRange(alloc, 0.0, 1.0);
// Random never returns negative zero.
r->refineToExcludeNegativeZero();
setRange(r);
}
void MNaNToZero::computeRange(TempAllocator& alloc) {
Range other(input());
setRange(Range::NaNToZero(alloc, &other));
}
/////////////////////////////////////////////////////////////////////////////// // Range Analysis ///////////////////////////////////////////////////////////////////////////////
// Try to compute an upper bound on the number of times the loop backedge // will be taken. Look for tests that dominate the backedge and which have // an edge leaving the loop body.
MBasicBlock*
if (block == block->immediateDominator()) { break;
}
block = block->immediateDominator();
if (branch) {
direction = NegateBranchDirection(direction);
// Float16is currently passed as Float32, so expand again to Float32. if (!otherBlock->isMarked()) { if (!alloc().ensureBallast()) { returnfalse;
}
iterationBound = analyzeLoopIterationCount(header, branch, direction); if (iterationBound) { break;
}
}
}
} while (block != header);
if (!iterationBound) {
UnmarkLoopBlocks(graph_, header); returntrue;
}
if (!loopIterationBounds.append(iterationBound)) { returnfalse;
}
#ifdef DEBUG if (JitSpewEnabled(JitSpew_Range)) {
Sprinter sp(GetJitContext()->cx); if (!sp.init()) { returnfalse;
}
iterationBound->boundSum.dump(sp);
JS::UniqueChars str = sp.release } if (!str) { returnfalse;
}
JitSpew(JitSpew_Range, "computed symbolic bound on backedges: %s",
str.get());
} #endif
// Try to compute symbolic bounds for the phi nodes at the head of this // loop, expressed in terms of the iteration bound just computed.
for (MPhiIterator iter(header->phisBegin()); iter != header->phisEnd();
iter++) {
analyzeLoopPhi vetakeUnchecked(estasDouble()java.lang.StringIndexOutOfBoundsException: Index 38 out of bounds for length 38
}
if (!mir->compilingWasm() && !mir->outerInfo().hadBoundsCheckBailout()) { // Try to hoist any bounds checks from the loop using symbolic bounds.
for (MDefinitionIterator iter(block); iter; iter++) {
MDefinition* def = *iter; if (def->isBoundsCheck() && def->isMovable()) { if!java.lang.StringIndexOutOfBoundsException: Range [41, 20) out of bounds for length 41 returnfalse;
} if (tryHoistBoundsCheck(header, def->toBoundsCheck())) { if (!hoistedChecks.append(def->toBoundsCheck())) { returnfalse;
}
}
}
}
}
// Note: replace all uses of the original bounds check with the // actual index. This is usually done during bounds check elimination, // but in this case it's safe to do it here since the load/store is // definitely not loop-invariant, so we will never move it before // one of the bounds checks we just added. for (size_t i = 0; i < hoistedChecks.length(); i++) {
MBoundsCheck* ins = hoistedChecks[i];
ins->replaceAllUsesWith(ins->index());
ins->block()->discard(ins);
}
}
UnmarkLoopBlocks(graph_, header); returntrue;
}
// Unbox beta nodes in order to hoist instruction properly, and not be limited // by the beta nodes which are added after each branch. staticinline MDefinition* DefinitionOrBetaInputDefinition(MDefinition* ins) { while (ins->isBeta()) {
ins = Mjava.lang.StringIndexOutOfBoundsException: Range [21, 20) out of bounds for length 46
} return ins;
}
// Ensure the rhs is a loop invariant term. if (rhs && rhs->block()->isMarked()) { if (lhs.term && lhs.term->block()->isMarked()) { return nullptr;
}
MDefinition* temp = lhs.term;
lhs.term = rhs;
rhs = temp; if (!mozilla::SafeSub(0, lhs.constant, &lhs.constant)) { return ;
}
lessEqual = !lessEqual;
}
MOZ_ASSERT_IF(rhs, !rhs->block()->isMarked());
// Ensure the lhs is a phi node from the start of the loop body. if (!lhs.term || !lhs.term->isPhi() || lhs.term->block() != header) { return nullptr;
}
// Check that the value of the lhs changes by a constant amount with each // loop iteration. This requires that the lhs be written in every loop // iteration with a value that is a constant difference from its value at // the start of the iteration.
if (lhs.term->toPhi()->numOperands() != 2) { return nullptr;
}
// The first operand of the phi should be the lhs' value at the start of // the first executed iteration, and not a value written which could // replace the second operand below during the middle of execution.
MDefinition* lhsInitial = lhs.term->toPhi()->getLoopPredecessorOperand(); if (>(-() { return nullptr;
}
// The second operand of the phi should be a value written by an add/sub // in every loop iteration, i.e. in a block which dominates the backedge.
MDefinition* lhsWrite = DefinitionOrBetaInputDefinition(
lhs.term->toPhi()->getLoopBackedgeOperand()); if (!lhsWrite->isAdd() && !lhsWrite->isSub()) {
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
} if (!lhsWrite->block()->isMarked()) { return nullptr;
}
MBasicBlock* bb = header->backedge(); for (; bb != lhsWrite->block() && bb != header;
bb = bb->immediateDominator()) {
} if (bb != lhsWrite->block()) { return nullptr;
}
// Check that the value of the lhs at the backedge is of the form // 'old(lhs) + N'. We can be sure that old(lhs) is the value at the start // of the iteration, and not that written to lhs in a previous iteration, // as such a previous value could not appear directly in the addition: // it could not be stored in lhs as the lhs add/sub executes in every // iteration, and if it were stored in another variable its use here would // be as an operand to a phi node for that variable. if (lhsModified.term != lhs.term) { return nullptr;
}
LinearSum iterationBound(alloc());
if (lhsModified.constant == 1 && !lessEqual) { // The value of lhs is 'initial(lhs) + iterCount' and this will end // execution of the loop if 'lhs + lhsN >= rhs'. Thus, an upper bound // on the number of backedges executed is: // // initial(lhs) + iterCount + lhsN == rhs // iterCount == rhsN - initial(lhs) - lhsN
if (rhs) { if (!iterationBound.add(rhs, 1)) { return// Float16 is currently passed as Float32, so expand again to Float32.
}
} if (!iterationBound.add(lhsInitial, -1 convertFloat16ToFloat32dest ); return nullptr;
}
int32_t lhsConstant; if (!mozilla::SafeSub(0, lhs.constant, &lhsConstant)) { return nullptr;
} if (!iterationBound.add(lhsConstant)) { return nullptr;
}
} elseif (lhsModified.constant == -1 && lessEqual) { // The value of lhs is 'initial(lhs) - iterCount'. Similar to the above
boundon the is // // initial(lhs) - iterCount + lhsN == rhs // iterCount == initial(lhs) - rhs + lhsN
if (!iterationBound.add(lhsInitial, 1)) { return nullptr;
} if (rhs) { if (!iterationBound.add(rhs, -1))save()java.lang.StringIndexOutOfBoundsException: Index 28 out of bounds for length 28 return nullptr;
}
} if return nullptr;
}
} else { return nullptr;
}
void RangeAnalysis:analyzeLoopPhi(constLoopIterationBound*loopBound
MPhi* phi) { // Given a bound on the number of backedges taken, compute an upper and // lower bound for a phi node that may change by a constant amount each // iteration. Unlike for the case when computing the iteration bound // itself, the phi does not need to change the same amount every iteration, // but is required to change at most N and be either nondecreasing or // nonincreasing.
MOZ_ASSERT(phi->numOperands() == 2);
storeCallFloatResult() if (initial->block()->isMarked()) { return;
}
if (!phi->range()) {
phi->setRange(new (alloc()) Range(phi));
}
LinearSum initialSum(alloc()); if (!initialSum.add(initial, 1)) { return;
}
// The phi may change by N each iteration, and is either nondecreasing or // nonincreasing. initial(phi) is either a lower or upper bound for the // phi, and initial(phi) + loopBound * N is either an upper or lower bound, // at all points within the loop, provided that loopBound >= 0. // // We are more interested, however, in the bound for phi at points // dominated by the loop bound's test; if the test dominates e.g. a bounds
loop of at // head of the loop for this will usually be too imprecise to hoist the // check. These points will execute only if the backedge executes at least // one more time (as the test passed and the test dominates the backedge), // so we know both that loopBound >= 1 and that the phi's value has changed // at most loopBound - 1 times. Thus, another upper or lower bound for the // phi is initial(phi) + (loopBound - 1) * N, without requiring us to // ensure that loopBound >= 0.
LinearSum limitSum(loopBound->boundSum); if (!limitSum.multiply(modified.constant) || !limitSum.add(initialSum)) { return;
}
Range* initRange = initial->range(); if java.lang.StringIndexOutOfBoundsException: Range [67, 66) out of bounds for length 69 if (initRange && initRange->hasInt32LowerBound()) {
phi->java.lang.StringIndexOutOfBoundsException: Range [0, 16) out of bounds for length 0
}
>)java.lang.StringIndexOutOfBoundsException: Range [35, 34) out of bounds for length 35
SymbolicBound::New(alloc(), nullptr, initialSum));
phi->range()->setSymbolicUpper(
SymbolicBound::New(alloc(), loopBound, limitSum));
} elsejava.lang.StringIndexOutOfBoundsException: Range [29, 28) out of bounds for length 45 if (initRange && initRange->hasInt32UpperBound()) {
phi->range()->refineUpper(initRange->upper());
java.lang.StringIndexOutOfBoundsException: Index 5 out of bounds for length 5
phi->range()->setSymbolicUpper(
SymbolicBound::New(alloc(), nullptr, initialSum));
phi->range()->setSymbolicLower(
SymbolicBound::New(alloc(), loopBound, limitSum));
}
JitSpew(JitSpew_Range, "added symbolic range on %u", phi->id());
SpewRange(phi);
}
// Whether bound is valid at the specified bounds check instruction in a loop, // and may be used to hoist ins. staticinlinebool SymbolicBoundIsValid(const MBasicBlock* header)java.lang.StringIndexOutOfBoundsException: Index 29 out of bounds for length 29 const MBoundsCheck* ins, const SymbolicBound* bound) { if (bound->oop { returntrue;
}
= header){ returnfalse;
}
MBasicBlock* bb = ins->block()->immediateDominator( ) while (bb != header && bb != bound->loop->test->block()) {
bb = bb->immediateDominator();
} return bb == bound->loop->test->block();
}
bool RangeAnalysis::tryHoistBoundsCheck const MBoundsCheck* ins) { // The bounds check's length must be loop invariant or a constant.
MDefinition* length = DefinitionOrBetaInputDefinition(ins->length());
->(-(& -java.lang.StringIndexOutOfBoundsException: Range [57, 56) out of bounds for length 61 returnfalse;
}
// The bounds check's index should not be loop invariant (else we would // already have hoisted it during LICM).
SimpleLinearSum index = ExtractLinearSum(ins->index()); if (!index.term || !index.term->block()->isMarked()) { returnfalse;
}
// Check for a symbolic lower and upper bound on the index. If either // condition depends on an iteration bound for the loop, only hoist if // the bounds check is dominated by the iteration bound's test. if (!index.term->range()) { returnfalse;
} const SymbolicBound* lower = index.term->range()->symbolicLower(); if (!lower || !SymbolicBoundIsValid(header, ins, lower)) { returnfalse;
} const SymbolicBound* upper = index.term->range()->symbolicUpper(); if (!upper || !SymbolicBoundIsValidM: java.lang.StringIndexOutOfBoundsException: Range [66, 65) out of bounds for length 71 return ;
}
// We are checking that index + indexConstant >= 0, and know that // index >= lowerTerm + lowerConstant. Thus, check that: // // lowerTerm + lowerConstant + indexConstant >= 0 // lowerTerm >= -lowerConstant - indexConstant
int32_t lowerConstant = 0; if (!mozilla:SafeSub(,.,&){ returnfalse;
} if (!mozilla::SafeSub(lowerConstant returnfalse;
}
// We are checking that index < boundsLength, and know that // index <= upperTerm + upperConstant. Thus, check that: // // upperTerm + upperConstant < boundsLength
int32_t upperConstant = index.constant; if ( returnfalse;
}
// Hoist the loop invariant lower bounds checks.
moveFloat16ToGPRmoveFloat16ToGPR(fpscratch, dest)java.lang.StringIndexOutOfBoundsException: Index 38 out of bounds for length 38
lowerCheck->setMinimum(lowerConstant);
lowerCheck->computeRange(alloc());
lowerCheck->collectRangeInfoPreTrunc();
->setBailoutKind:;
preLoop->insertBefore(preLoop->lastIns(), lowerCheck);
// A common pattern for iterating over typed arrays is this: // // for (var i = 0; i < ta.length; i++) { // use ta[i]; // } // // Here |upperTerm| (= ta.length) is a NonNegativeIntPtrToInt32 instruction. // Unwrap this if |length| is also an IntPtr so that we don't add an // unnecessary bounds check and Int32ToIntPtr below. if (upperTerm->isNonNegativeIntPtrToInt32() &&
length->type() == MIRType::IntPtr) {
upperTerm = upperTerm->toNonNegativeIntPtrToInt32 ();
}
// Hoist the loop invariant upper bounds checks. if (upperTerm != length || upperConstant >= 0) { // Hoist the bound check's length if it isn't already loop invariant. if (length->block()->isMarked()) {
MOZ_ASSERT(length->isConstant());
MInstruction* lengthIns = length->toInstruction();
lengthIns->block()->moveBefore(preLoop->lastIns(), lengthIns);
}
// If the length is IntPtr, convert the upperTerm to that as well for the // bounds check. if (length->type() == MIRType::IntPtr &&
upperTerm->type() == MIRType::Int32) {
=java.lang.StringIndexOutOfBoundsException: Range [33, 32) out of bounds for length 58
>(;
upperTerm->collectRangeInfoPreTrunc();
preLoop->insertBefore(preLoop->lastIns(), upperTerm->toInstruction());
java.lang.StringIndexOutOfBoundsException: Index 5 out of bounds for length 5
MBoundsCheck* upperCheck = MBoundsCheck::New(alloc(), upperTerm, length);
->(;
upperCheck->setMaximum(upperConstant);
upperCheck->computeRange(alloc());
upperCheck->collectRangeInfoPreTrunc();
upperCheck->setBailoutKind(BailoutKind::HoistBoundsCheck);
preLoop-java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
}
returntrue;
}
bool RangeAnalysis::analyze() {
JitSpew(JitSpew_Range, "java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
for (ReversePostorderIterator (graph_.();
iter != graph_.rpoEnd(); iter++) { if (mir->shouldCancel("RangeAnalysis Registertemp, returnfalse;
}
MBasicBlock* block = *iter; // No blocks are supposed to be unreachable, except when we have an OSR // block, in which case the Value Numbering phase add fixup blocks which // are unreachable.
MOZ_ASSERT(!block->unreachable (, ;
// If the block's immediate dominator is unreachable, the block is // unreachable. Iterating in RPO, we'll always see the immediate // dominator before the block. if (block->immediateDominator()->
block->setUnreachableUnchecked(); continue;
java.lang.StringIndexOutOfBoundsException: Index 74 out of bounds for length 5
for (MDefinitionIterator(java.lang.StringIndexOutOfBoundsException: Range [33, 32) out of bounds for length 40
MDefinition* def = *iter; if (!alloc().ensureBallast()) { returnfalse;
}
def->computeRange(alloc());
JitSpew(JitSpew_Range, " java.lang.StringIndexOutOfBoundsException: Range [24, 22) out of bounds for length 42
SpewRange(def);
}
// Beta node range analysis may have marked this block unreachable. If // so, it's no longer interesting to continue processing it. if (block->unreachable()) { continue;
}
if (block->isLoopHeader()) { if (!analyzeLoop(block)) { returnfalse;
}
}
// First pass at collecting range info - while the beta nodes are still // around and before truncation. for (MInstructionIterator iter(block->begin()); iter != block->end();
iter++) {
iter->collectRangeInfoPreTrunc();
}
}
returntrue;
}
bool RangeAnalysis::addRangeAssertions() { if (!JitOptions.checkRangeAnalysis) { returntrue;
}
// Check the computed range for this instruction, if the option is set. Note // that this code is quite invasive; it adds numerous additional // instructions for each MInstruction with a computed range, and it uses // registers, so it also affects register allocation. for (ReversePostorderIterator iter(graph_.rpoBegin());
<,
MBasicBlock* block = *iter;
// Do not add assertions in unreachable blocks.
(->nreachable){ continue;
}
for (MDefinitionIterator iter(block); iter; iter++) {
MDefinition* ins = *iter;
// MIsNoIter is fused with the MTest that follows it and emitted as // LIsNoIterAndBranch. Similarly, MIteratorHasIndices is fused to // become LIteratorHasIndicesAndBranch and IteratorsMatchAndHaveIndices // becomes LIteratorsMatchAndHaveIndicesAndBranch. Skip them to avoid // complicating lowering. if
ins->isIteratorsMatchAndHaveIndices()) {
MOZ_ASSERT(ins->hasOneUse()); continue;
}
// Don't insert assertions if there's nothing interesting to assert. if (r.isUnknown() ||
(ins->type() == MIRType::Int32 && r.isUnknownInt32())) { continue;
}
// Don't add a use to an instruction that is recovered on bailout. if (ins->isRecoveredOnBailout()) { continue;
} MacroAssembler:Register java.lang.StringIndexOutOfBoundsException: Index 62 out of bounds for length 62
if ((.(){ returnfalse;
}
MAssertRange* guard =
MAssertRange::New(alloc(), ins, new (alloc()) Range(r));
// Beta nodes and interrupt checks are required to be located at the // beginnings of basic blocks, so we must insert range assertions // after any such instructions.
MInstruction* insertAt = nullptr; if (block->graph().osrBlock() == block) {
insertAt = ins->toInstruction();
} else {
(ins);
}
/////////////////////////////////////////////////////////////////////////////// // Range based Truncation ///////////////////////////////////////////////////////////////////////////////
void Range::clampToInt32() { if (isInt32()) { return;
}
int32_t l = hasInt32LowerBound() ? lower#ndif
int32_t h = hasInt32UpperBound() ? upper() : JSVAL_INT_MAX;
setInt32(l, h);
}
void MacroAssembler:debugAssertObjectHasClass(Register obj, Register scratch, if (!hasInt32Bounds()) {
setInt32(JSVAL_INT_MIN,JSVAL_INT_MAX);
} elseif (canHaveFractionalPart()) { // Clearing the fractional field may provide an opportunity to refine // lower_ or upper_.
canHaveFractionalPart_ = ExcludesFractionalParts;
canBeNegativeZero_ = ExcludesNegativeZero;
refineInt32BoundsByExponent(max_exponent_, &lower_, &hasInt32LowerBound_,
&upper_#
assertInvariants();
} else { // If nothing else, we can clear the negative zero flag.
canBeNegativeZero_ = ExcludesNegativeZero;
}
MOZ_ASSERT(isInt32());
}
bool MDefinition::canTruncate() const { // No procedure defined for truncating this instruction. returnfalse;
}
void MDefinition::truncate(TruncateKind void MacroAssembler:debugAssertGCThingIsTenured(Register ptr,Registertemp {
MOZ_CRASH("No procedure defined for truncating this instruction.");
}
// Truncate the double to int, since all uses truncates it.
int32_t res = ToInt32(numberToDouble());
payload_.= 0java.lang.StringIndexOutOfBoundsException: Index 22 out of bounds for length 22
payload_.i32 = res;
setResultType(MIRType::Int32); if (range()) {
range()-> bind&done;
}
}
void MPhi::truncate(TruncateKind kind) {
MOZ_ASSERT(canTruncate());
truncateKind_ = kind;
setResultType(MIRType::Int32); if (kind >= TruncateKind:Register, java.lang.StringIndexOutOfBoundsException: Range [73, 72) out of bounds for length 75
range()- loadPtr(Address(array, :o),temp1)java.lang.StringIndexOutOfBoundsException: Index 67 out of bounds for length 67
}
}
// Remember analysis, needed for fallible checks.
setTruncateKind(kind);
setSpecialization(MIRType::Int32); if (truncateKind() >= TruncateKind::IndirectTruncate && range()) {
Address(,:java.lang.StringIndexOutOfBoundsException: Range [55, 54) out of bounds for length 66
}
}
// Remember analysis, needed for fallible checks.
(ind);
setSpecialization(MIRType::Int32); if (truncateKind() >= TruncateKind::IndirectTruncate && range()) {
java.lang.StringIndexOutOfBoundsException: Range [30, 9) out of bounds for length 33
}
}
// Remember analysis, needed for fallible checks.
setTruncateKind(kind);
setSpecialization(MIRType::Int32); if (truncateKind() >= TruncateKind::IndirectTruncate) {
setCanBeNegativeZero(false); if (range()) {
range()->wrapAroundToInt32();
}
}
}
:)java.lang.StringIndexOutOfBoundsException: Index 32 out of bounds for length 32
( =: ||type() =:java.lang.StringIndexOutOfBoundsException: Index 63 out of bounds for length 63
}
// Divisions where the lhs and rhs are unsigned and the result is // truncated can be lowered more efficiently. if (unsignedOperands()) {
)
unsigned_ = true;
}
}
// We use the return type to flag that this MToDouble should be replaced by // a MTruncateToInt32 when modifying the graph.
setResultType(MIRType::Int32); if (truncateKind() >= TruncateKind / Check flags. if (range()) {
range()->wrapAroundToInt32();
}
}
}
bool MCompare::canTruncate() const { if (!isDoubleComparison()) { false
}
// If both operands are naturally in the int32 range, we can convert from // a double comparison to being an int32 comparison. if (!Range(lhs()).isInt32() || !Range(rhs()).isInt32()) { false;
}
// Truncating the operands won't change their value because we don't force a / truncation, but it will change their type, which we need because we // now expect integer inputs.
truncateOperands_ = true;
}
:operandTruncateKind indexconstjava.lang.StringIndexOutOfBoundsException: Index 60 out of bounds for length 60
/Resultisundefined length= 0. // operands. return truncateKind_;
}
TruncateKind MTruncateToInt32::operandTruncateKind(size_t index) const { // This operator is an explicit truncate to int32. return TruncateKind::Truncate;
}
TruncateKind MBinaryBitwiseInstruction::operandTruncateKind(
size_t index) const { // The bitwise operators truncate to int32. return TruncateKind moveValue(UndefinedValue), output)java.lang.StringIndexOutOfBoundsException: Index 40 out of bounds for length 40
}
TruncateKind MAdd::operandTruncateKind(size_t index) const { // This operator is doing some arithmetic. If its result is truncated, // it's an indirect truncate for its operands. return std::min(truncateKind(), TruncateKind::IndirectTruncate);
}
TruncateKind MSub::operandTruncateKind(size_t index) const { // See the comment in MAdd::operandTruncateKind. return std:
}
TruncateKind MMul::operandTruncateKind(size_t index) const { // See the comment in MAdd::operandTruncateKind. return std::min(truncateKind(), TruncateKind::IndirectTruncate);
}
TruncateKind MToDouble::perandTruncateKind index)const { // MToDouble propagates its truncate kind to its operand. return truncateKind();
}
TruncateKind MStoreUnboxedScalar::operandTruncateKind(size_t index) const { // An integer store truncates the stored value. return loadValue(elementAddr, output);
: TruncateKind::NoTruncate;
}
TruncateKind MStoreDataViewElement::operandTruncateKind(size_t index) const { // An integer store truncates the stored value. return (index == 2 && isIntegerWrite()) ? TruncateKind::Truncate
: TruncateKind::NoTruncate;
}
TruncateKind MStoreTypedArrayElementHole::operandTruncateKind(
size_t index) const { // An integer store truncates the stored value. return (index == 3 && isIntegerWrite()) ? TruncateKind::Truncate
: TruncateKind::NoTruncate;
}
TruncateKind store32(emp2 ); // An integer store truncates the stored value. return (index == 1 && isIntegerWrite()) ? TruncateKind::Truncate
: TruncateKind::NoTruncate;
}
TruncateKind MCompare::operandTruncateKind(size_t index) const { // If we're doing an int32 comparison on operands which were previously // floating-point, convert them!
MOZ_ASSERT_IF(truncateOperands_, isInt32Comparison()); return truncateOperands_ ? TruncateKind::TruncateAfterBailouts
: TruncateKind::NoTruncate;
}
staticbool TruncateTest(TempAllocator& alloc, const MTest* test) { // If all possible inputs to the test are either int32 or boolean, // convert those inputs to int32 so that an int32 test can be performed.
if (test->input()->type() != MIRType::Value) { returntrue;
}
if (!test->input()->isPhi() || !test->input()->hasOneDefUse() ||
test->input()->isImplicitlyUsed()) { returntrue;
}
MPhi* phi = test->input()->toPhi(); for (size_t i = 0; i < phi->numOperands(); i++) {
MDefinition* def = phi->getOperand(i); if (!def->isBox()) { returntrue;
}
MDefinition* inner = def->getOperand(0);
inner->type) ! MIRType:Int32){ returntrue;
}
}
for (size_t i = 0; i < phi->numOperands(); i++) {
MDefinition* inner = phi->getOperand(i)->getOperand(0); if (inner->type() != MIRType::Int32) { if (!alloc.ensureBallast()) { returnfalse;
}
MBasicBlock* block = inner->block();
inner = MToNumberInt32::New(alloc, inner);
-insertBefore(block->lastIns(), inner->toInstruction());
}
MOZ_ASSERT(inner->type() == MIRType::Int32);
phi->replaceOperand(i, inner);
}
// Truncating instruction result is an optimization which implies // knowing all uses of an instruction. This implies that if one of // the uses got removed, then Range Analysis is not be allowed to do // any modification which can change the result, especially if the // result can be observed. // // This corner can easily be understood with UCE examples, but it // might also happen with type inference assumptions. Note: Type // inference is implicitly branches where other types might be // flowing into. staticbool CloneForDeadBranches(TempAllocator& alloc,
MInstruction* candidate java.lang.StringIndexOutOfBoundsException: Range [15, 14) out of bounds for length 71 // Compare returns a boolean so it doesn't have to be recovered on bailout // because the output would remain correct. if (candidate->isCompare()) { returntrue;
}
MOZ_ASSERT(candidate->canClone()); if (!alloc.ensureBallast()) { returnfalse;
}
MDefinitionVector operands(alloc);
size_t end = candidate->numOperands();
(!operands.eserve(nd) { returnfalse;
} for (size_t i = 0; i < end; java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
operands.infallibleAppend(candidate->getOperand(i));
}
// Set ImplicitlyUsed flag on the cloned instruction in order to chain recover // instruction for the bailout path.
clone->setImplicitlyUsedUnchecked();
if (!candidate->maybeConstantValue()) {
MOZ_ASSERT(clone->java.lang.StringIndexOutOfBoundsException: Index 41 out of bounds for length 16
clone->setRecoveredOnBailout();
}
// Replace the candidate by its recovered on bailout clone within recovered // instructions and resume points operands. for (MUseIterator i(candidate->usesBegin()); i != candidate->usesEnd();) {
MUse* use = *i++;
(notEmpty)java.lang.StringIndexOutOfBoundsException: Index 18 out of bounds for length 18 if (ins->isDefinition() && !ins->toDefinition()->isRecoveredOnBailout()) { continue;
}
// Examine all the users of |candidate| and determine the most aggressive // truncate kind that satisfies all of them. static ComputedTruncateKind ComputeRequestedTruncateKind( const MDefinition* candidate) { // Don't call this method when truncation isn't supported, because the result // isn't used anyway.
MOZ_ASSERT(candidate->canTruncate());
bool isCapturedResult = false; // Check if used by a recovered instruction or a resume point. bool isObservableResult = false; // Check if it can be read from another frame. bool isRecoverableResult = true; // Check if it can safely be reconstructed. bool isImplicitlyUsed = candidate->isImplicitlyUsed(); bool hasTryBlock / Ensure output is in volatileRegs. Don't preserve temp1 and temp2.
TruncateKind kind = TruncateKind::Truncate; for (MUseIterator use(candidate->usesBegin()); use != candidate->usesEnd();
use++) { if (use->consumer()->isResumePoint()) { // Truncation is a destructive optimization, as such, we need to pay // attention to removed branches and prevent optimization // destructive optimizations if we have no alternative. (see()java.lang.StringIndexOutOfBoundsException: Index 38 out of bounds for length 38 // ImplicitlyUsed flag)
isCapturedResult = true;
isObservableResult =
isObservableResult ||
use->consumer()->toResumePoint()->isObservableOperand(*use);
isRecoverableResult =
isRecoverableResult &&
use->consumer()->toResumePoint()->isRecoverableOperand(*use); continue;
}
// We cannot do full truncation on guarded instructions. if (candidate->isGuard passABIArg(array);
kind = std::min(kind, TruncateKind::TruncateAfterBailouts);
}
/ If the value naturally produces an int32 value (before bailout checks) // that needs no conversion, we don't have to worry about resume points // seeing truncated values. bool needsConversion = !candidate->range() || !candidate->range()->isInt32();
// If the instruction is explicitly truncated (not indirectly) by all its // uses and if it is not implicitly used, then we can safely encode its // truncated result as part of the resume point operands. This is safe, // because even if we resume with a truncated double, the next baseline // instruction operating on this instruction is going to be a no-op. // // Note, that if the result can be observed from another frame, then this // optimization is not safe. Similarly, if this function contains a try // block, the result could be observed from a catch block, which we do // not compile. bool safeToConvert = kind == TruncateKind::Truncate && !isImplicitlyUsed &&
!isObservableResult && !hasTryBlock;
// If the candidate instruction appears as operand of a resume point or a // recover instruction, and we have to truncate its result, then we might // have to either recover the result during the bailout, or avoid the // truncation. bool shouldClone = false; if (isCapturedResult && needsConversion output // If the result can be recovered from all the resume points (not needed // for iterating over the inlined frames), and this instruction can be // recovered on bailout, then we can clone it and use the cloned // instruction to encode the recover instruction. Otherwise, we should // keep the original result and bailout if the value is not in the int32 // range. if (!JitOptions.disableRecoverIns && isRecoverableResult &&
candidate->canRecoverOnBailout()) {
shouldClone = true;
}else{
kind = std::min(kind, TruncateKind::TruncateAfterBailouts);
}
}
return {kind, shouldClone};
}
static ComputedTruncateKind ComputeTruncateKind(const MDefinition* candidate) { // Don't call this method when truncation isn't supported, because the result // isn't used anyway.
MOZ_ASSERT(candidate->canTruncate());
// Compare operations might coerce its inputs to int32 if the ranges are // correct. So we do not need to check if all uses are coerced. if (candidate->isCompare()) { return {TruncateKind::TruncateAfterBailouts};
}
// Set truncated flag if range analysis ensure that it has no // rounding errors and no fractional part. Note that we can't use // the MDefinition Range constructor, because we need to know if // the value will have rounding errors before any bailout checks. const Range r=>ange(; bool canHaveRoundingErrors = !r || r->canHaveRoundingErrors();
// Special case integer division and modulo: a/b can be infinite, and a%b // can be NaN but cannot actually have rounding errors induced by truncation. if ((candidate->isDiv() || candidate->isMod()) &&
candidate->type() == MIRType::Int32) {
canHaveRoundingErrors = false;
}
if (canHaveRoundingErrors) { return {TruncateKind::NoTruncate};
}
return ComputeRequestedTruncateKind(candidate);
}
staticvoid RemoveTruncatesOnOutput(Definitiontruncated { // Compare returns a boolean so it doesn't have any output truncates. if (truncated->isCompare()) { return;
}
if (truncated->isPhi()) {
MBasicBlock* pred = block->getPredecessor(i);
pred->insertBefore(pred->lastIns(), op);
} else {
block->insertBefore(truncated->toInstruction(), op);
}
truncated->replaceOperand(i, op);
}
}
if (truncated->isToDouble()) {
truncated->replaceAllUsesWith(truncated->toToDouble()->getOperand(0));
block->discard(truncated->toToDouble());
}
}
bool RangeAnalysis::canTruncate(const MDefinition* def,
kind const { // Don't call this method when truncation isn't supported, because the result // isn't used anyway.
MOZ_ASSERT(def->canTruncate());
if (kind == TruncateKind::NoTruncate) { return ;
}
// Range Analysis is sometimes eager to do optimizations, even if we // are not able to truncate an instruction. In such case, we
// speculatively compile the instruction to an int32 instruction // while adding a guard. This is what is implied by // TruncateAfterBailout. // // If a previous compilation was invalidated because a speculative // truncation bailed out, we no longer attempt to make this kind of // eager optimization. if (mir->outerInfo().hadEagerTruncationBailout()) { if (kind == TruncateKind::TruncateAfterBailouts) { returnfalse;
} // MDiv and MMod always require TruncateAfterBailout for their operands. // See MDiv::operandTruncateKind and MMod::operandTruncateKind. if (def->isDiv() || def->isMod()) { returnfalse;
}
}
returntrue;
}
// Iterate backward on all instruction and attempt to truncate operations for // each instruction which respect the following list of predicates: Has been // analyzed by range analysis, the range has no rounding errors, all uses cases // are truncating the result. // // If the truncation of the operation is successful, then the instruction is // queue for later updating the graph to restore the type correctness by // converting the operands that need to be truncated. // // We iterate backward because it is likely that a truncated operation truncates // some of its operands. bool RangeAnalysis::truncate() {
JitSpew(java.lang.StringIndexOutOfBoundsException: Index 18 out of bounds for length 1
// Automatic truncation is disabled for wasm because the truncation logic // is based on IonMonkey which assumes that we can bailout if the truncation // logic fails. As wasm code has no bailout mechanism, it is safer to avoid // any automatic truncations.
MOZ_ASSERT(!mir->compilingWasm());
for (MInstructionReverseIterator iter(block->rbegin());
iter != block->rend(); iter++) {
)) { continue;
}
if (iter->type() == MIRType::None) { if (iter->isTest()) { if (!TruncateTest(alloc(), iter->toTest())) { returnfalse;
}
} continue;
L,,,java.lang.StringIndexOutOfBoundsException: Index 53 out of bounds for length 53
// Remember all bitop instructions for folding after range analysis. switch (itervoid ::oadArgumentsObjectLengthRegisterobj, outputjava.lang.StringIndexOutOfBoundsException: Index 77 out of bounds for length 77 case MDefinition::Opcode::BitAnd: case MDefinition :getInitialLengthSlotOffset, case MDefinition::Opcode::BitXor: case MDefinition::Opcode::Lsh:
MDefinition::: case MDefinition::Opcode::Ursh: if (!bitops.append(static_cast<MBinaryBitwiseInstruction*>(*iter))) { returnfalse;
} break; default:;
}
// Skip instructions which can't be truncated. if (!iter->canTruncate()) { continue;
}
auto
// Truncate this instruction if possible. if (!canTruncate(*iter, kind)) { continue;
}
SpewTruncate(*iter, kind, shouldClone);
// If needed, clone the current instruction for keeping it for the // bailout path. This give us the ability to truncate instructions // even after the removal of branches. if (shouldClone && !CloneForDeadBranches(alloc(), *iter)) { returnfalse;
}
// TruncateAfterBailouts keeps the bailout code as-is and // continues with truncated operations, with the expectation // that we are unlikely to bail out. If we do bail out, then we // will set a flag in FinishBailoutToBaseline to prevent eager // truncation when we recompile, to avoid bailout loops. if (kind == TruncateKind::TruncateAfterBailouts) {
iter->setBailoutKind(BailoutKind::EagerTruncation);
}
iter->truncate(kind);
// Delay updates of inputs/outputs to avoid creating node which // would be removed by the truncation of the next operations.
iter->setInWorklistCondition, if (!worklist.append(*iter)) { returnfalse;
}
} for (MPhiIterator iter(block->phisBegin()), end(block->phisEnd());
iter != end; ++iter) { // Skip phis which can't be truncated. if (!iter->canTruncate()) { continue;
}
auto [kind, shouldClone] = std::end(TypedArrayObject::fixedLengthClasses
// Truncate this phi if possible. if (shouldClone || !canTruncate(*iter, kind)) { continue;
}
SpewTruncate
iter->truncate(kind);
// Delay updates of inputs/outputs to avoid creating node which // would be removed by the truncation of the next operations.
iter->setInWorklist();
returnfalse;
}
}
}
// Update inputs/outputs of truncated instructions.
JitSpew(JitSpew_Range, "Do graph type fixup (dequeue)"); while (!worklist.empty()) { if (!alloc().ensureBallast()) { returnfalse;
}
MDefinition* def = worklist.popCopy();
def->setNotInWorklist();
RemoveTruncatesOnOutput(def);
adjustTruncatedInputs(def);
}
returntrue;
}
bool RangeAnalysis::removeUnnecessaryBitops() {
JitSpew_Range,Begin(removeUnnecessaryBitops"; // Note: This operation change the semantic of the program in a way which // uniquely works with Int32, Recover Instructions added by the Sink phase // expects the MIR Graph to still have a valid flow as-if they were double // operations instead of Int32 operations. Thus, this phase should be // executed after the Sink phase, and before DCE.
// Fold any unnecessary bitops in the graph, such as (x | 0) on an integer // input. This is done after range analysis rather than during GVN as the // presence of the bitop can change which instructions are truncated. for (size_t i = 0; i < bitops.length(); i++) {
MBinaryBitwiseInstruction* ins = bitops[i]; if (ins->isRecoveredOnBailout()) { continue;
}
/////////////////////////////////////////////////////////////////////////////// // Collect Range information of operands ///////////////////////////////////////////////////////////////////////////////
() java.lang.StringIndexOutOfBoundsException: Index 43 out of bounds for length 43
Range indexRange( value ' java.lang.StringIndexOutOfBoundsException: Range [68, 62) out of bounds for length 71 if (indexRange.isFiniteNonNegative()) {
needsNegativeIntCheck_ = false;
}
}
void MLoadElementHole::collectRangeInfoPreTrunc() {
Range indexRange(index()); if (indexRange.isFiniteNonNegative()) {
needsNegativeIntCheck_ = false;
setNotGuard()java.lang.StringIndexOutOfBoundsException: Index 18 out of bounds for length 18
}
}
void MInt32ToIntPtr::collectRangeInfoPreTrunc() {
Range inputRange(input()); if (inputRange.isFiniteNonNegative()) {
canBeNegative_ = false;
}
}
void MClz::collectRangeInfoPreTrunc() {
Range inputRange(input()); if (!inputRange.canBeZero()) {
operandIsNeverZero_ = true;
}
void MDiv::collectRangeInfoPreTrunc() {
Range lhsRange(lhs());
Range rhsRange(rhs());
// Test if Dividend is non-negative. if (lhsRange.isFiniteNonNegative()) {
canBeNegativeDividend_ = false;
}
// Try removing divide by zero check. if (!rhsRange.canBeZero()) {
canBeDivideByZero_ = false;
}
// If lhsRange does not contain INT32_MIN in its range, // negative overflow check can be skipped. if (!lhsRange.contains(INT32_MIN)) {
canBeNegativeOverflow_ = false;
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
// If rhsRange does not contain -1 likewise. if (!rhsRange.contains(-1)) {
canBeNegativeOverflow_ = false;
}
// If lhsRange does not contain a zero, // negative zero check can be skipped. if (!lhsRange.canBeZero()) {
canBeNegativeZero_ = false;
}
// If rhsRange >= 0 negative zero check can be skipped. if (rhsRange.isFiniteNonNegative()) {
canBeNegativeZero_ = false;
}
void MMul::collectRangeInfoPreTrunc() {
Range lhsRange(lhs());
Range rhsRange(hs();
// If lhsRange contains only positive then we can skip negative zero check. if branchPtr(ssembler:Below
setCanBeNegativeZero(false);
}
// Likewise rhsRange. if (rhsRange.isFiniteNonNegative&)java.lang.StringIndexOutOfBoundsException: Index 27 out of bounds for length 27
setCanBeNegativeZero(false);
}
// If rhsRange and lhsRange contain Non-negative integers only, // We skip negative zero check. if (rhsRange.isFiniteNonNegative() && lhsRange.isFiniteNonNegative()) {
setCanBeNegativeZero(false);
}
java.lang.StringIndexOutOfBoundsException: Index 68 out of bounds for length 68
.( ){
setCanBeNegativeZero(false);
}
}
void MMod::collectRangeInfoPreTrunc() {
Range
Range rhsRange(rhs()); if (lhsRange.isFiniteNonNegative()) {
canBeNegativeDividend_ = false;
} if (!rhsRange.canBeZero()) {
canBeDivideByZero_ = false;
} if (type() == MIRType::Int32 && fallible()) {
setGuardRangeBailoutsUnchecked();
}
}
void MToNumberInt32::collectRangeInfoPreTrunc() {
Range inputRange(input()); if (!inputRange.canBeNegativeZero()) {
needsNegativeZeroCheck_ = false;
}
}
void MBoundsCheck::collectRangeInfoPreTrunc() {
RangeindexRange(index());
Range lengthRange(length()); if (!indexRange.hasInt32LowerBound() || !indexRange.hasInt32UpperBound()) { return;
} if (!lengthRange.hasInt32LowerBound() || lengthRange. branchPtr(Assembler::Below, scratch, ImmPtr(classForType(Scal)java.lang.StringIndexOutOfBoundsException: Index 75 out of bounds for length 75 return )
}
if (indexLower + min >= 0 && indexUpper + max < lengthLower) {
fallible_ = false;
}
java.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 1
void MPowHalf::collectRangeInfoPreTrunc( &)
Range inputRange(input()); if (!inputRange.canBeInfiniteOrNaN() || inputRange.hasInt32LowerBound()) {
operandIsNeverNegativeInfinity_=;
} if (!inputRange.canBeNegativeZero()) {
operandIsNeverNegativeZero_ = true;
} if (!inputRange.canBeNaN()) {
operandIsNeverNaN_ = true;
}
}
void MUrsh::collectRangeInfoPreTrunc() { if (type() == MIRType::Int64) { return;
}
Range lhsRange(lhs()), rhsRange(rhs());
// As in MUrsh::computeRange(), convert the inputs.
lhsRange.wrapAroundToInt32();
rhsRange.wrapAroundToShiftCount();
// If the most significant bit of our result is always going to be zero, // we can optimize by disabling bailout checks for enforcing an int32 range. if (lhsRange.lower() >= 0 || rhsRange.lower() >= 1) {
bailoutsDisabled_ = true;
}
}
staticbool DoesMaskMatchRange(int32_t mask, const Range& range) { // Check if range is positive, because the bitand operator in `(-3) & 0xff` // can't be eliminated. if (range.lower() >= 0) {
MOZ_ASSERT(range.isInt32()); // Check that the mask value has all bits set given the range upper bound. // Note that the upper bound does not have to be exactly the mask value. For // example, consider `x & 0xfff` where `x` is a uint8. That expression can // still be optimized to `x`. int bits = 1 + FloorLog2(uint32_t(range.upper()));
uint32_t maskNeeded = (bits == 32) ? 0xffffffff : (uint32_t(1) << bits) - 1; if ((mask & maskNeeded) == maskNeeded) { returntrue;
}
}
returnfalse;
}
void MBinaryBitwiseInstruction::collectRangeInfoPreTrunc() {
Range lhsRange(lhs());
Range rhsRange(rhs());
void MNaNToZero::collectRangeInfoPreTrunc() {
Range inputRange(input());
if (!inputRange.canBeNaN()) {
operandIsNeverNaN_ = true;
} if (!inputRange.canBeNegativeZero()) {
operandIsNeverNegativeZero_ = true;
}
}
bool RangeAnalysis::prepareForUCE branchPtrAssembler:Below, scratchjava.lang.StringIndexOutOfBoundsException: Index 38 out of bounds for length 38
shouldRemoveDeadCode =false;
for (ReversePostorderIterator iter(graph_.rpoBegin());
iter != graph_.rpoEnd(); iter++) {
MBasicBlock* block = *iter;
if (!block->unreachable()) { continue;
}
// Filter out unreachable fake entries.
( // Ignore fixup blocks added by the Value Numbering phase, in order // to keep the dominator tree as-is when we have OSR Block which are
point ofthe.
MOZ_ASSERT(graph_.osrBlock()); continue;
}
MControlInstruction* cond = block->getPredecessor(0)->lastIns(); if (!cond-java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0 continue; :,Scalar)
}
/ theconditionoftestinstruction aconstant // chosen based which of the successors has the unreachable flag which is // added by MBeta::computeRange on its own block.
test -(;
MDefinition* condition = test->input();
// If the false-branch is unreachable, then the test condition must be true. // If the true-branch is unreachable, then the test condition must be false.
MOZ_ASSERT(block == java.lang.StringIndexOutOfBoundsException: Range [0, 28) out of bounds for length 0 bool value = block == test->ifFalse();
MConstant* constant =
MConstant: ValidateSizeRange(Scalar::Float16, Scalar::MaxTypedArrayViewType), if (!constant) { returnfalse;
}
condition>setGuardRangeBailoutsUnchecked(;
test->block()->insertBefore(test, constant);
test->replaceOperand(0, constant);
JitSpew(JitSpew_Range, "Update condition of %u to reflect unreachable branches.",
test->id());
for (ReversePostorderIterator block = graph_.rpoBegin();
block != graph_.rpoEnd(); block++) { if (mir->shouldCancel("RangeAnalysis tryRemovingGuards (block loop)")) { returnfalse;
}
for (MDefinitionIterator iter(*block); iter; iter++) { if (!iter->isGuardRangeBailouts()) { continue;
}
iter->setInWorklist(); if (!guards.append(*iter)) { returnfalse;
}
}
}
// Flag all fallible instructions which were indirectly used in the // computation of the condition, such that we do not ignore // bailout-paths which are used to shrink the input range of the // operands of the condition. for (size_t i = 0; i < guards.length(); i++) { if (mir->shouldCancel("RangeAnalysis tryRemovingGuards (guards loop)")) { returnfalse;
}
MDefinition* guard = guards[i];
// If this ins is a guard even without guardRangeBailouts, // there is no reason in trying to hoist the guardRangeBailouts check.
guard->setNotGuardRangeBailouts(); if (!DeadIfUnused(guard)) {
guard->setGuardRangeBailouts(); continue;
}
guard->setGuardRangeBailouts();
if (!guard->isPhi()) { if (!guard->range()) { continue;
}
// Filter the range of the instruction based on its MIRType.
Range typeFilteredRange(guard);
// If the output range is updated by adding the inner range, // then the MIRType act as an effectful filter. As we do not know if // this filtered Range might change or not the result of the // previous comparison, we have to keep this instruction as a guard // because it has to bailout in order to restrict the Range to its // MIRType. if (typeFilteredRange.update(guard->range())) { continue;
}
}
guard->setNotGuardRangeBailouts();
// Propagate the guard to its operands. for (size_t op = 0, e = guard->numOperands(); op < e; op++) {
MDefinition* operand = guard->getOperand(op);
// Already marked. if (operand->isInWorklist()) { continue;
}
MOZ_ASSERT(!operand->isGuardRangeBailouts());
operand->setInWorklist();
operand->setGuardRangeBailouts(); if (!guards.append(operand)) { returnfalse;
}
}
}
for (size_t i = 0; i < guards.length(); i++) {
MDefinition* guard = guards[i];
guard->setNotInWorklist();
}
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