tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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KnownClass.cpp (3243B)

      1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
      2 * vim: set ts=8 sts=2 et sw=2 tw=80:
      3 * This Source Code Form is subject to the terms of the Mozilla Public
      4 * License, v. 2.0. If a copy of the MPL was not distributed with this
      5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      6 
      7 #include "jit/KnownClass.h"
      8 
      9 #include "jit/MIR-wasm.h"
     10 #include "jit/MIR.h"
     11 #include "vm/ArrayObject.h"
     12 #include "vm/Iteration.h"
     13 #include "vm/JSFunction.h"
     14 #include "vm/PlainObject.h"  // js::PlainObject
     15 #include "vm/RegExpObject.h"
     16 
     17 using namespace js;
     18 using namespace js::jit;
     19 
     20 KnownClass jit::GetObjectKnownClass(const MDefinition* def) {
     21  MOZ_ASSERT(def->type() == MIRType::Object);
     22 
     23  switch (def->op()) {
     24    case MDefinition::Opcode::NewArray:
     25    case MDefinition::Opcode::NewArrayDynamicLength:
     26    case MDefinition::Opcode::NewArrayObject:
     27    case MDefinition::Opcode::Rest:
     28    case MDefinition::Opcode::ArgumentsSlice:
     29    case MDefinition::Opcode::FrameArgumentsSlice:
     30    case MDefinition::Opcode::InlineArgumentsSlice:
     31      return KnownClass::Array;
     32 
     33    case MDefinition::Opcode::NewObject:
     34    case MDefinition::Opcode::NewPlainObject:
     35    case MDefinition::Opcode::CreateThis:
     36      return KnownClass::PlainObject;
     37 
     38    case MDefinition::Opcode::Lambda:
     39    case MDefinition::Opcode::FunctionWithProto:
     40      return KnownClass::Function;
     41 
     42    case MDefinition::Opcode::RegExp:
     43      return KnownClass::RegExp;
     44 
     45    case MDefinition::Opcode::NewIterator:
     46      switch (def->toNewIterator()->type()) {
     47        case MNewIterator::ArrayIterator:
     48          return KnownClass::ArrayIterator;
     49        case MNewIterator::StringIterator:
     50          return KnownClass::StringIterator;
     51        case MNewIterator::RegExpStringIterator:
     52          return KnownClass::RegExpStringIterator;
     53      }
     54      MOZ_CRASH("unreachable");
     55 
     56    case MDefinition::Opcode::Phi: {
     57      if (def->numOperands() == 0) {
     58        return KnownClass::None;
     59      }
     60 
     61      MDefinition* op = def->getOperand(0);
     62      // Check for Phis to avoid recursion for now.
     63      if (op->isPhi()) {
     64        return KnownClass::None;
     65      }
     66 
     67      KnownClass known = GetObjectKnownClass(op);
     68      if (known == KnownClass::None) {
     69        return KnownClass::None;
     70      }
     71 
     72      for (size_t i = 1; i < def->numOperands(); i++) {
     73        op = def->getOperand(i);
     74        if (op->isPhi() || GetObjectKnownClass(op) != known) {
     75          return KnownClass::None;
     76        }
     77      }
     78 
     79      return known;
     80    }
     81 
     82    default:
     83      break;
     84  }
     85 
     86  return KnownClass::None;
     87 }
     88 
     89 const JSClass* jit::GetObjectKnownJSClass(const MDefinition* def) {
     90  switch (GetObjectKnownClass(def)) {
     91    case KnownClass::PlainObject:
     92      return &PlainObject::class_;
     93    case KnownClass::Array:
     94      return &ArrayObject::class_;
     95    case KnownClass::Function:
     96      return &FunctionClass;
     97    case KnownClass::RegExp:
     98      return &RegExpObject::class_;
     99    case KnownClass::ArrayIterator:
    100      return &ArrayIteratorObject::class_;
    101    case KnownClass::StringIterator:
    102      return &StringIteratorObject::class_;
    103    case KnownClass::RegExpStringIterator:
    104      return &RegExpStringIteratorObject::class_;
    105    case KnownClass::None:
    106      break;
    107  }
    108 
    109  return nullptr;
    110 }