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author | Matt A. Tobin <mattatobin@localhost.localdomain> | 2018-02-02 04:16:08 -0500 |
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committer | Matt A. Tobin <mattatobin@localhost.localdomain> | 2018-02-02 04:16:08 -0500 |
commit | 5f8de423f190bbb79a62f804151bc24824fa32d8 (patch) | |
tree | 10027f336435511475e392454359edea8e25895d /js/src/jit/StackSlotAllocator.h | |
parent | 49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff) | |
download | uxp-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.gz |
Add m-esr52 at 52.6.0
Diffstat (limited to 'js/src/jit/StackSlotAllocator.h')
-rw-r--r-- | js/src/jit/StackSlotAllocator.h | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/js/src/jit/StackSlotAllocator.h b/js/src/jit/StackSlotAllocator.h new file mode 100644 index 0000000000..07c9ee7635 --- /dev/null +++ b/js/src/jit/StackSlotAllocator.h @@ -0,0 +1,110 @@ +/* -*- 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/. */ + +#ifndef jit_StackSlotAllocator_h +#define jit_StackSlotAllocator_h + +#include "mozilla/Unused.h" + +#include "jit/Registers.h" + +namespace js { +namespace jit { + +class StackSlotAllocator +{ + js::Vector<uint32_t, 4, SystemAllocPolicy> normalSlots; + js::Vector<uint32_t, 4, SystemAllocPolicy> doubleSlots; + uint32_t height_; + + void addAvailableSlot(uint32_t index) { + // Ignoring OOM here (and below) is fine; it just means the stack slot + // will be unused. + mozilla::Unused << normalSlots.append(index); + } + void addAvailableDoubleSlot(uint32_t index) { + mozilla::Unused << doubleSlots.append(index); + } + + uint32_t allocateQuadSlot() { + MOZ_ASSERT(SupportsSimd); + // This relies on the fact that any architecture specific + // alignment of the stack pointer is done a priori. + if (height_ % 8 != 0) + addAvailableSlot(height_ += 4); + if (height_ % 16 != 0) + addAvailableDoubleSlot(height_ += 8); + return height_ += 16; + } + uint32_t allocateDoubleSlot() { + if (!doubleSlots.empty()) + return doubleSlots.popCopy(); + if (height_ % 8 != 0) + addAvailableSlot(height_ += 4); + return height_ += 8; + } + uint32_t allocateSlot() { + if (!normalSlots.empty()) + return normalSlots.popCopy(); + if (!doubleSlots.empty()) { + uint32_t index = doubleSlots.popCopy(); + addAvailableSlot(index - 4); + return index; + } + return height_ += 4; + } + + public: + StackSlotAllocator() : height_(0) + { } + + static uint32_t width(LDefinition::Type type) { + switch (type) { +#if JS_BITS_PER_WORD == 32 + case LDefinition::GENERAL: + case LDefinition::OBJECT: + case LDefinition::SLOTS: +#endif + case LDefinition::INT32: + case LDefinition::FLOAT32: return 4; +#if JS_BITS_PER_WORD == 64 + case LDefinition::GENERAL: + case LDefinition::OBJECT: + case LDefinition::SLOTS: +#endif +#ifdef JS_PUNBOX64 + case LDefinition::BOX: +#endif +#ifdef JS_NUNBOX32 + case LDefinition::TYPE: + case LDefinition::PAYLOAD: +#endif + case LDefinition::DOUBLE: return 8; + case LDefinition::SINCOS: + case LDefinition::SIMD128INT: + case LDefinition::SIMD128FLOAT: return 16; + } + MOZ_CRASH("Unknown slot type"); + } + + uint32_t allocateSlot(LDefinition::Type type) { + switch (width(type)) { + case 4: return allocateSlot(); + case 8: return allocateDoubleSlot(); + case 16: return allocateQuadSlot(); + } + MOZ_CRASH("Unknown slot width"); + } + + uint32_t stackHeight() const { + return height_; + } +}; + +} // namespace jit +} // namespace js + +#endif /* jit_StackSlotAllocator_h */ |