The Tor Browser: comparison js/src/jit/BaselineInspector.cpp

--1:000000000000
+:0931b7c51986
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+* vim: set ts=8 sts=4 et sw=4 tw=99:
+* This Source Code Form is subject to the terms of the Mozilla Public
+* License, v. 2.0. If a copy of the MPL was not distributed with this
+* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#include "jit/BaselineInspector.h"
+#include "mozilla/DebugOnly.h"
+#include "jit/BaselineIC.h"
+using namespace js;
+using namespace js::jit;
+using mozilla::DebugOnly;
+bool
+SetElemICInspector::sawOOBDenseWrite() const
+{
+if (!icEntry_)
+return false;
+// Check for a SetElem_DenseAdd stub.
+for (ICStub *stub = icEntry_->firstStub(); stub; stub = stub->next()) {
+if (stub->isSetElem_DenseAdd())
+return true;
+}
+// Check for a write hole bit on the SetElem_Fallback stub.
+ICStub *stub = icEntry_->fallbackStub();
+if (stub->isSetElem_Fallback())
+return stub->toSetElem_Fallback()->hasArrayWriteHole();
+return false;
+}
+bool
+SetElemICInspector::sawOOBTypedArrayWrite() const
+{
+if (!icEntry_)
+return false;
+// Check for SetElem_TypedArray stubs with expectOutOfBounds set.
+for (ICStub *stub = icEntry_->firstStub(); stub; stub = stub->next()) {
+if (!stub->isSetElem_TypedArray())
+continue;
+if (stub->toSetElem_TypedArray()->expectOutOfBounds())
+return true;
+}
+return false;
+}
+bool
+SetElemICInspector::sawDenseWrite() const
+{
+if (!icEntry_)
+return false;
+// Check for a SetElem_DenseAdd or SetElem_Dense stub.
+for (ICStub *stub = icEntry_->firstStub(); stub; stub = stub->next()) {
+if (stub->isSetElem_DenseAdd() || stub->isSetElem_Dense())
+return true;
+}
+return false;
+}
+bool
+SetElemICInspector::sawTypedArrayWrite() const
+{
+if (!icEntry_)
+return false;
+// Check for a SetElem_TypedArray stub.
+for (ICStub *stub = icEntry_->firstStub(); stub; stub = stub->next()) {
+if (stub->isSetElem_TypedArray())
+return true;
+}
+return false;
+}
+bool
+BaselineInspector::maybeShapesForPropertyOp(jsbytecode *pc, ShapeVector &shapes)
+{
+// Return a list of shapes seen by the baseline IC for the current op.
+// An empty list indicates no shapes are known, or there was an uncacheable
+// access.
+JS_ASSERT(shapes.empty());
+if (!hasBaselineScript())
+return true;
+JS_ASSERT(isValidPC(pc));
+const ICEntry &entry = icEntryFromPC(pc);
+ICStub *stub = entry.firstStub();
+while (stub->next()) {
+Shape *shape;
+if (stub->isGetProp_Native()) {
+shape = stub->toGetProp_Native()->shape();
+} else if (stub->isSetProp_Native()) {
+shape = stub->toSetProp_Native()->shape();
+} else {
+shapes.clear();
+return true;
+}
+// Don't add the same shape twice (this can happen if there are multiple
+// SetProp_Native stubs with different TypeObject's).
+bool found = false;
+for (size_t i = 0; i < shapes.length(); i++) {
+if (shapes[i] == shape) {
+found = true;
+break;
+}
+}
+if (!found && !shapes.append(shape))
+return false;
+stub = stub->next();
+}
+if (stub->isGetProp_Fallback()) {
+if (stub->toGetProp_Fallback()->hadUnoptimizableAccess())
+shapes.clear();
+} else {
+if (stub->toSetProp_Fallback()->hadUnoptimizableAccess())
+shapes.clear();
+}
+// Don't inline if there are more than 5 shapes.
+if (shapes.length() > 5)
+shapes.clear();
+return true;
+}
+ICStub *
+BaselineInspector::monomorphicStub(jsbytecode *pc)
+{
+if (!hasBaselineScript())
+return nullptr;
+const ICEntry &entry = icEntryFromPC(pc);
+ICStub *stub = entry.firstStub();
+ICStub *next = stub->next();
+if (!next || !next->isFallback())
+return nullptr;
+return stub;
+}
+bool
+BaselineInspector::dimorphicStub(jsbytecode *pc, ICStub **pfirst, ICStub **psecond)
+{
+if (!hasBaselineScript())
+return false;
+const ICEntry &entry = icEntryFromPC(pc);
+ICStub *stub = entry.firstStub();
+ICStub *next = stub->next();
+ICStub *after = next ? next->next() : nullptr;
+if (!after || !after->isFallback())
+return false;
+*pfirst = stub;
+*psecond = next;
+return true;
+}
+MIRType
+BaselineInspector::expectedResultType(jsbytecode *pc)
+{
+// Look at the IC entries for this op to guess what type it will produce,
+// returning MIRType_None otherwise.
+ICStub *stub = monomorphicStub(pc);
+if (!stub)
+return MIRType_None;
+switch (stub->kind()) {
+case ICStub::BinaryArith_Int32:
+if (stub->toBinaryArith_Int32()->allowDouble())
+return MIRType_Double;
+return MIRType_Int32;
+case ICStub::BinaryArith_BooleanWithInt32:
+case ICStub::UnaryArith_Int32:
+case ICStub::BinaryArith_DoubleWithInt32:
+return MIRType_Int32;
+case ICStub::BinaryArith_Double:
+case ICStub::UnaryArith_Double:
+return MIRType_Double;
+case ICStub::BinaryArith_StringConcat:
+case ICStub::BinaryArith_StringObjectConcat:
+return MIRType_String;
+default:
+return MIRType_None;
+}
+}
+// Whether a baseline stub kind is suitable for a double comparison that
+// converts its operands to doubles.
+static bool
+CanUseDoubleCompare(ICStub::Kind kind)
+{
+return kind == ICStub::Compare_Double || kind == ICStub::Compare_NumberWithUndefined;
+}
+// Whether a baseline stub kind is suitable for an int32 comparison that
+// converts its operands to int32.
+static bool
+CanUseInt32Compare(ICStub::Kind kind)
+{
+return kind == ICStub::Compare_Int32 || kind == ICStub::Compare_Int32WithBoolean;
+}
+MCompare::CompareType
+BaselineInspector::expectedCompareType(jsbytecode *pc)
+{
+ICStub *first = monomorphicStub(pc), *second = nullptr;
+if (!first && !dimorphicStub(pc, &first, &second))
+return MCompare::Compare_Unknown;
+if (CanUseInt32Compare(first->kind()) && (!second || CanUseInt32Compare(second->kind()))) {
+ICCompare_Int32WithBoolean *coerce =
+first->isCompare_Int32WithBoolean()
+? first->toCompare_Int32WithBoolean()
+: ((second && second->isCompare_Int32WithBoolean())
+? second->toCompare_Int32WithBoolean()
+: nullptr);
+if (coerce) {
+return coerce->lhsIsInt32()
+? MCompare::Compare_Int32MaybeCoerceRHS
+: MCompare::Compare_Int32MaybeCoerceLHS;
+}
+return MCompare::Compare_Int32;
+}
+if (CanUseDoubleCompare(first->kind()) && (!second || CanUseDoubleCompare(second->kind()))) {
+ICCompare_NumberWithUndefined *coerce =
+first->isCompare_NumberWithUndefined()
+? first->toCompare_NumberWithUndefined()
+: (second && second->isCompare_NumberWithUndefined())
+? second->toCompare_NumberWithUndefined()
+: nullptr;
+if (coerce) {
+return coerce->lhsIsUndefined()
+? MCompare::Compare_DoubleMaybeCoerceLHS
+: MCompare::Compare_DoubleMaybeCoerceRHS;
+}
+return MCompare::Compare_Double;
+}
+return MCompare::Compare_Unknown;
+}
+static bool
+TryToSpecializeBinaryArithOp(ICStub **stubs,
+uint32_t nstubs,
+MIRType *result)
+{
+DebugOnly<bool> sawInt32 = false;
+bool sawDouble = false;
+bool sawOther = false;
+for (uint32_t i = 0; i < nstubs; i++) {
+switch (stubs[i]->kind()) {
+case ICStub::BinaryArith_Int32:
+sawInt32 = true;
+break;
+case ICStub::BinaryArith_BooleanWithInt32:
+sawInt32 = true;
+break;
+case ICStub::BinaryArith_Double:
+sawDouble = true;
+break;
+case ICStub::BinaryArith_DoubleWithInt32:
+sawDouble = true;
+break;
+default:
+sawOther = true;
+break;
+}
+}
+if (sawOther)
+return false;
+if (sawDouble) {
+*result = MIRType_Double;
+return true;
+}
+JS_ASSERT(sawInt32);
+*result = MIRType_Int32;
+return true;
+}
+MIRType
+BaselineInspector::expectedBinaryArithSpecialization(jsbytecode *pc)
+{
+if (!hasBaselineScript())
+return MIRType_None;
+MIRType result;
+ICStub *stubs[2];
+const ICEntry &entry = icEntryFromPC(pc);
+ICStub *stub = entry.fallbackStub();
+if (stub->isBinaryArith_Fallback() &&
+stub->toBinaryArith_Fallback()->hadUnoptimizableOperands())
+{
+return MIRType_None;
+}
+stubs[0] = monomorphicStub(pc);
+if (stubs[0]) {
+if (TryToSpecializeBinaryArithOp(stubs, 1, &result))
+return result;
+}
+if (dimorphicStub(pc, &stubs[0], &stubs[1])) {
+if (TryToSpecializeBinaryArithOp(stubs, 2, &result))
+return result;
+}
+return MIRType_None;
+}
+bool
+BaselineInspector::hasSeenNonNativeGetElement(jsbytecode *pc)
+{
+if (!hasBaselineScript())
+return false;
+const ICEntry &entry = icEntryFromPC(pc);
+ICStub *stub = entry.fallbackStub();
+if (stub->isGetElem_Fallback())
+return stub->toGetElem_Fallback()->hasNonNativeAccess();
+return false;
+}
+bool
+BaselineInspector::hasSeenNegativeIndexGetElement(jsbytecode *pc)
+{
+if (!hasBaselineScript())
+return false;
+const ICEntry &entry = icEntryFromPC(pc);
+ICStub *stub = entry.fallbackStub();
+if (stub->isGetElem_Fallback())
+return stub->toGetElem_Fallback()->hasNegativeIndex();
+return false;
+}
+bool
+BaselineInspector::hasSeenAccessedGetter(jsbytecode *pc)
+{
+if (!hasBaselineScript())
+return false;
+const ICEntry &entry = icEntryFromPC(pc);
+ICStub *stub = entry.fallbackStub();
+if (stub->isGetProp_Fallback())
+return stub->toGetProp_Fallback()->hasAccessedGetter();
+return false;
+}
+bool
+BaselineInspector::hasSeenNonStringIterNext(jsbytecode *pc)
+{
+JS_ASSERT(JSOp(*pc) == JSOP_ITERNEXT);
+if (!hasBaselineScript())
+return false;
+const ICEntry &entry = icEntryFromPC(pc);
+ICStub *stub = entry.fallbackStub();
+return stub->toIteratorNext_Fallback()->hasNonStringResult();
+}
+bool
+BaselineInspector::hasSeenDoubleResult(jsbytecode *pc)
+{
+if (!hasBaselineScript())
+return false;
+const ICEntry &entry = icEntryFromPC(pc);
+ICStub *stub = entry.fallbackStub();
+JS_ASSERT(stub->isUnaryArith_Fallback() || stub->isBinaryArith_Fallback());
+if (stub->isUnaryArith_Fallback())
+return stub->toUnaryArith_Fallback()->sawDoubleResult();
+else
+return stub->toBinaryArith_Fallback()->sawDoubleResult();
+return false;
+}
+JSObject *
+BaselineInspector::getTemplateObject(jsbytecode *pc)
+{
+if (!hasBaselineScript())
+return nullptr;
+const ICEntry &entry = icEntryFromPC(pc);
+for (ICStub *stub = entry.firstStub(); stub; stub = stub->next()) {
+switch (stub->kind()) {
+case ICStub::NewArray_Fallback:
+return stub->toNewArray_Fallback()->templateObject();
+case ICStub::NewObject_Fallback:
+return stub->toNewObject_Fallback()->templateObject();
+case ICStub::Rest_Fallback:
+return stub->toRest_Fallback()->templateObject();
+case ICStub::Call_Scripted:
+if (JSObject *obj = stub->toCall_Scripted()->templateObject())
+return obj;
+break;
+default:
+break;
+}
+}
+return nullptr;
+}
+JSObject *
+BaselineInspector::getTemplateObjectForNative(jsbytecode *pc, Native native)
+{
+if (!hasBaselineScript())
+return nullptr;
+const ICEntry &entry = icEntryFromPC(pc);
+for (ICStub *stub = entry.firstStub(); stub; stub = stub->next()) {
+if (stub->isCall_Native() && stub->toCall_Native()->callee()->native() == native)
+return stub->toCall_Native()->templateObject();
+}
+return nullptr;
+}
+DeclEnvObject *
+BaselineInspector::templateDeclEnvObject()
+{
+if (!hasBaselineScript())
+return nullptr;
+JSObject *res = &templateCallObject()->as<ScopeObject>().enclosingScope();
+JS_ASSERT(res);
+return &res->as<DeclEnvObject>();
+}
+CallObject *
+BaselineInspector::templateCallObject()
+{
+if (!hasBaselineScript())
+return nullptr;
+JSObject *res = baselineScript()->templateScope();
+JS_ASSERT(res);
+return &res->as<CallObject>();
+}
+JSObject *
+BaselineInspector::commonGetPropFunction(jsbytecode *pc, Shape **lastProperty, JSFunction **commonGetter)
+{
+if (!hasBaselineScript())
+return nullptr;
+const ICEntry &entry = icEntryFromPC(pc);
+for (ICStub *stub = entry.firstStub(); stub; stub = stub->next()) {
+if (stub->isGetProp_CallScripted()  ||
+stub->isGetProp_CallNative()    ||
+stub->isGetProp_CallNativePrototype())
+{
+ICGetPropCallGetter *nstub = static_cast<ICGetPropCallGetter *>(stub);
+*lastProperty = nstub->holderShape();
+*commonGetter = nstub->getter();
+return nstub->holder();
+}
+}
+return nullptr;
+}
+JSObject *
+BaselineInspector::commonSetPropFunction(jsbytecode *pc, Shape **lastProperty, JSFunction **commonSetter)
+{
+if (!hasBaselineScript())
+return nullptr;
+const ICEntry &entry = icEntryFromPC(pc);
+for (ICStub *stub = entry.firstStub(); stub; stub = stub->next()) {
+if (stub->isSetProp_CallScripted() || stub->isSetProp_CallNative()) {
+ICSetPropCallSetter *nstub = static_cast<ICSetPropCallSetter *>(stub);
+*lastProperty = nstub->holderShape();
+*commonSetter = nstub->setter();
+return nstub->holder();
+}
+}
+return nullptr;
+}

The Tor Browser / file comparison

comparison: js/src/jit/BaselineInspector.cpp

js/src/jit/BaselineInspector.cpp