michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
michael@0:  * vim: set ts=8 sts=4 et sw=4 tw=99:
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef jit_StackSlotAllocator_h
michael@0: #define jit_StackSlotAllocator_h
michael@0: 
michael@0: #include "jit/Registers.h"
michael@0: 
michael@0: namespace js {
michael@0: namespace jit {
michael@0: 
michael@0: class StackSlotAllocator
michael@0: {
michael@0:     js::Vector<uint32_t, 4, SystemAllocPolicy> normalSlots;
michael@0:     js::Vector<uint32_t, 4, SystemAllocPolicy> doubleSlots;
michael@0:     uint32_t height_;
michael@0: 
michael@0:     void freeSlot(uint32_t index) {
michael@0:         normalSlots.append(index);
michael@0:     }
michael@0:     void freeDoubleSlot(uint32_t index) {
michael@0:         doubleSlots.append(index);
michael@0:     }
michael@0: 
michael@0:     uint32_t allocateDoubleSlot() {
michael@0:         if (!doubleSlots.empty())
michael@0:             return doubleSlots.popCopy();
michael@0:         if (height_ % 8 != 0)
michael@0:             normalSlots.append(height_ += 4);
michael@0:         return height_ += 8;
michael@0:     }
michael@0:     uint32_t allocateSlot() {
michael@0:         if (!normalSlots.empty())
michael@0:             return normalSlots.popCopy();
michael@0:         if (!doubleSlots.empty()) {
michael@0:             uint32_t index = doubleSlots.popCopy();
michael@0:             normalSlots.append(index - 4);
michael@0:             return index;
michael@0:         }
michael@0:         return height_ += 4;
michael@0:     }
michael@0: 
michael@0:   public:
michael@0:     StackSlotAllocator() : height_(0)
michael@0:     { }
michael@0: 
michael@0:     void freeSlot(LDefinition::Type type, uint32_t index) {
michael@0:         switch (type) {
michael@0: #if JS_BITS_PER_WORD == 32
michael@0:           case LDefinition::GENERAL:
michael@0:           case LDefinition::OBJECT:
michael@0:           case LDefinition::SLOTS:
michael@0: #endif
michael@0:           case LDefinition::INT32:
michael@0:           case LDefinition::FLOAT32: return freeSlot(index);
michael@0: #if JS_BITS_PER_WORD == 64
michael@0:           case LDefinition::GENERAL:
michael@0:           case LDefinition::OBJECT:
michael@0:           case LDefinition::SLOTS:
michael@0: #endif
michael@0: #ifdef JS_PUNBOX64
michael@0:           case LDefinition::BOX:
michael@0: #endif
michael@0: #ifdef JS_NUNBOX32
michael@0:           case LDefinition::TYPE:
michael@0:           case LDefinition::PAYLOAD:
michael@0: #endif
michael@0:           case LDefinition::DOUBLE:  return freeDoubleSlot(index);
michael@0:           default: MOZ_ASSUME_UNREACHABLE("Unknown slot type");
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     uint32_t allocateSlot(LDefinition::Type type) {
michael@0:         switch (type) {
michael@0: #if JS_BITS_PER_WORD == 32
michael@0:           case LDefinition::GENERAL:
michael@0:           case LDefinition::OBJECT:
michael@0:           case LDefinition::SLOTS:
michael@0: #endif
michael@0:           case LDefinition::INT32:
michael@0:           case LDefinition::FLOAT32: return allocateSlot();
michael@0: #if JS_BITS_PER_WORD == 64
michael@0:           case LDefinition::GENERAL:
michael@0:           case LDefinition::OBJECT:
michael@0:           case LDefinition::SLOTS:
michael@0: #endif
michael@0: #ifdef JS_PUNBOX64
michael@0:           case LDefinition::BOX:
michael@0: #endif
michael@0: #ifdef JS_NUNBOX32
michael@0:           case LDefinition::TYPE:
michael@0:           case LDefinition::PAYLOAD:
michael@0: #endif
michael@0:           case LDefinition::DOUBLE:  return allocateDoubleSlot();
michael@0:           default: MOZ_ASSUME_UNREACHABLE("Unknown slot type");
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     uint32_t stackHeight() const {
michael@0:         return height_;
michael@0:     }
michael@0: };
michael@0: 
michael@0: } // namespace jit
michael@0: } // namespace js
michael@0: 
michael@0: #endif /* jit_StackSlotAllocator_h */