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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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#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);
+
+#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_;
+ FloatRegisterSet allFloatSpills_;
+ uint32_t nunboxSlotsRemaining_;
+ uint32_t slotsOrElementsSlotsRemaining_;
+
+ private:
+ void advanceFromGcRegs();
+ void advanceFromGcSlots();
+ void advanceFromNunboxOrValueSlots();
+ [[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 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);
+};
+
+} // namespace jit
+} // namespace js
+
+#endif /* jit_Safepoints_h */