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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* 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
#ifndef jit_Safepoints_h
#define jit_Safepoints_h
#include <stddef.h>
#include <stdint.h>
#include "jit/BitSet.h"
#include "jit/CompactBuffer.h"
#include "jit/RegisterSets.h"
namespace js {
namespace jit {
class CodeLocationLabel;
class IonScript;
class SafepointIndex;
struct SafepointSlotEntry;
class TempAllocator;
class LAllocation;
class LSafepoint;
static const uint32_t INVALID_SAFEPOINT_OFFSET = uint32_t(-1);
class SafepointWriter {
CompactBufferWriter stream_;
BitSet localSlots_;
BitSet argumentSlots_;
public:
explicit SafepointWriter(uint32_t localSlotsSize, uint32_t argumentsSize);
[[nodiscard]] bool init(TempAllocator& alloc);
private:
// A safepoint entry is written in the order these functions appear.
uint32_t startEntry();
void writeOsiCallPointOffset(uint32_t osiPointOffset);
void writeGcRegs(LSafepoint* safepoint);
void writeGcSlots(LSafepoint* safepoint);
void writeSlotsOrElementsSlots(LSafepoint* safepoint);
void writeWasmAnyRefSlots(LSafepoint* safepoint);
#ifdef JS_PUNBOX64
void writeValueSlots(LSafepoint* safepoint);
#else
void writeNunboxParts(LSafepoint* safepoint);
#endif
void endEntry();
public:
void encode(LSafepoint* safepoint);
size_t size() const { return stream_.length(); }
const uint8_t* buffer() const { return stream_.buffer(); }
bool oom() const { return stream_.oom(); }
};
class SafepointReader {
CompactBufferReader stream_;
uint32_t localSlots_;
uint32_t argumentSlots_;
uint32_t currentSlotChunk_;
bool currentSlotsAreStack_;
uint32_t nextSlotChunkNumber_;
uint32_t osiCallPointOffset_;
GeneralRegisterSet gcSpills_;
GeneralRegisterSet valueSpills_;
GeneralRegisterSet slotsOrElementsSpills_;
GeneralRegisterSet allGprSpills_;
GeneralRegisterSet wasmAnyRefSpills_;
FloatRegisterSet allFloatSpills_;
uint32_t nunboxSlotsRemaining_;
uint32_t slotsOrElementsSlotsRemaining_;
uint32_t wasmAnyRefSlotsRemaining_;
private:
void advanceFromGcRegs();
void advanceFromGcSlots();
void advanceFromNunboxOrValueSlots();
void advanceFromSlotsOrElementsSlots();
[[nodiscard]] bool getSlotFromBitmap(SafepointSlotEntry* entry);
public:
SafepointReader(IonScript* script, const SafepointIndex* si);
static CodeLocationLabel InvalidationPatchPoint(IonScript* script,
const SafepointIndex* si);
uint32_t osiCallPointOffset() const { return osiCallPointOffset_; }
LiveGeneralRegisterSet gcSpills() const {
return LiveGeneralRegisterSet(gcSpills_);
}
LiveGeneralRegisterSet slotsOrElementsSpills() const {
return LiveGeneralRegisterSet(slotsOrElementsSpills_);
}
LiveGeneralRegisterSet wasmAnyRefSpills() const {
return LiveGeneralRegisterSet(wasmAnyRefSpills_);
}
LiveGeneralRegisterSet valueSpills() const {
return LiveGeneralRegisterSet(valueSpills_);
}
LiveGeneralRegisterSet allGprSpills() const {
return LiveGeneralRegisterSet(allGprSpills_);
}
LiveFloatRegisterSet allFloatSpills() const {
return LiveFloatRegisterSet(allFloatSpills_);
}
uint32_t osiReturnPointOffset() const;
// Returns true if a slot was read, false if there are no more slots.
[[nodiscard]] bool getGcSlot(SafepointSlotEntry* entry);
// Returns true if a slot was read, false if there are no more value slots.
[[nodiscard]] bool getValueSlot(SafepointSlotEntry* entry);
// Returns true if a nunbox slot was read, false if there are no more
// nunbox slots.
[[nodiscard]] bool getNunboxSlot(LAllocation* type, LAllocation* payload);
// Returns true if a slot was read, false if there are no more slots.
[[nodiscard]] bool getSlotsOrElementsSlot(SafepointSlotEntry* entry);
// Returns true if a slot was read, false if there are no more slots.
[[nodiscard]] bool getWasmAnyRefSlot(SafepointSlotEntry* entry);
};
} // namespace jit
} // namespace js
#endif /* jit_Safepoints_h */