Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 215 insertions, 0 deletions

diff --git a/js/src/gc/Nursery-inl.h b/js/src/gc/Nursery-inl.h
new file mode 100644
index 0000000000..3a29d76c07
--- /dev/null
+++ b/js/src/gc/Nursery-inl.h
@@ -0,0 +1,215 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=4 sw=2 et tw=80 ft=cpp:
+ *
+ * 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 gc_Nursery_inl_h
+#define gc_Nursery_inl_h
+
+#include "gc/Nursery.h"
+
+#include "gc/GCRuntime.h"
+#include "gc/RelocationOverlay.h"
+#include "js/TracingAPI.h"
+#include "vm/JSContext.h"
+#include "vm/NativeObject.h"
+
+inline JSRuntime* js::Nursery::runtime() const { return gc->rt; }
+
+template <typename T>
+bool js::Nursery::isInside(const SharedMem<T>& p) const {
+  return isInside(p.unwrap(/*safe - used for value in comparison above*/));
+}
+
+MOZ_ALWAYS_INLINE /* static */ bool js::Nursery::getForwardedPointer(
+    js::gc::Cell** ref) {
+  js::gc::Cell* cell = (*ref);
+  MOZ_ASSERT(IsInsideNursery(cell));
+  if (!cell->isForwarded()) {
+    return false;
+  }
+  const gc::RelocationOverlay* overlay = gc::RelocationOverlay::fromCell(cell);
+  *ref = overlay->forwardingAddress();
+  return true;
+}
+
+inline void js::Nursery::maybeSetForwardingPointer(JSTracer* trc, void* oldData,
+                                                   void* newData, bool direct) {
+  if (trc->isTenuringTracer()) {
+    setForwardingPointerWhileTenuring(oldData, newData, direct);
+  }
+}
+
+inline void js::Nursery::setForwardingPointerWhileTenuring(void* oldData,
+                                                           void* newData,
+                                                           bool direct) {
+  if (isInside(oldData)) {
+    setForwardingPointer(oldData, newData, direct);
+  }
+}
+
+inline void js::Nursery::setSlotsForwardingPointer(HeapSlot* oldSlots,
+                                                   HeapSlot* newSlots,
+                                                   uint32_t nslots) {
+  // Slot arrays always have enough space for a forwarding pointer, since the
+  // number of slots is never zero.
+  MOZ_ASSERT(nslots > 0);
+  setDirectForwardingPointer(oldSlots, newSlots);
+}
+
+inline void js::Nursery::setElementsForwardingPointer(ObjectElements* oldHeader,
+                                                      ObjectElements* newHeader,
+                                                      uint32_t capacity) {
+  // Only use a direct forwarding pointer if there is enough space for one.
+  setForwardingPointer(oldHeader->elements(), newHeader->elements(),
+                       capacity > 0);
+}
+
+inline void js::Nursery::setForwardingPointer(void* oldData, void* newData,
+                                              bool direct) {
+  if (direct) {
+    setDirectForwardingPointer(oldData, newData);
+    return;
+  }
+
+  setIndirectForwardingPointer(oldData, newData);
+}
+
+inline void js::Nursery::setDirectForwardingPointer(void* oldData,
+                                                    void* newData) {
+  MOZ_ASSERT(isInside(oldData));
+  MOZ_ASSERT(!isInside(newData));
+
+  new (oldData) BufferRelocationOverlay{newData};
+}
+
+inline void* js::Nursery::tryAllocateCell(gc::AllocSite* site, size_t size,
+                                          JS::TraceKind kind) {
+  // Ensure there's enough space to replace the contents with a
+  // RelocationOverlay.
+  // MOZ_ASSERT(size >= sizeof(RelocationOverlay));
+  MOZ_ASSERT(size % gc::CellAlignBytes == 0);
+  MOZ_ASSERT(size_t(kind) < gc::NurseryTraceKinds);
+  MOZ_ASSERT_IF(kind == JS::TraceKind::String, canAllocateStrings());
+  MOZ_ASSERT_IF(kind == JS::TraceKind::BigInt, canAllocateBigInts());
+
+  void* ptr = tryAllocate(sizeof(gc::NurseryCellHeader) + size);
+  if (MOZ_UNLIKELY(!ptr)) {
+    return nullptr;
+  }
+
+  new (ptr) gc::NurseryCellHeader(site, kind);
+
+  void* cell =
+      reinterpret_cast<void*>(uintptr_t(ptr) + sizeof(gc::NurseryCellHeader));
+  if (!cell) {
+    MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE(
+        "Successful allocation cannot result in nullptr");
+  }
+
+  // Update the allocation site. This code is also inlined in
+  // MacroAssembler::updateAllocSite.
+  uint32_t allocCount = site->incAllocCount();
+  if (allocCount == 1) {
+    pretenuringNursery.insertIntoAllocatedList(site);
+  }
+  MOZ_ASSERT_IF(site->isNormal(), site->isInAllocatedList());
+
+  gc::gcprobes::NurseryAlloc(cell, kind);
+  return cell;
+}
+
+inline void* js::Nursery::tryAllocate(size_t size) {
+  MOZ_ASSERT(isEnabled());
+  MOZ_ASSERT(!JS::RuntimeHeapIsBusy());
+  MOZ_ASSERT_IF(currentChunk_ == startChunk_, position() >= startPosition_);
+  MOZ_ASSERT(size % gc::CellAlignBytes == 0);
+  MOZ_ASSERT(position() % gc::CellAlignBytes == 0);
+
+  if (MOZ_UNLIKELY(currentEnd() < position() + size)) {
+    return nullptr;
+  }
+
+  void* ptr = reinterpret_cast<void*>(position());
+  if (!ptr) {
+    MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE(
+        "Successful allocation cannot result in nullptr");
+  }
+
+  position_ = position() + size;
+
+  DebugOnlyPoison(ptr, JS_ALLOCATED_NURSERY_PATTERN, size,
+                  MemCheckKind::MakeUndefined);
+
+  return ptr;
+}
+
+inline bool js::Nursery::registerTrailer(PointerAndUint7 blockAndListID,
+                                         size_t nBytes) {
+  MOZ_ASSERT(trailersAdded_.length() == trailersRemoved_.length());
+  MOZ_ASSERT(nBytes > 0);
+  if (MOZ_UNLIKELY(!trailersAdded_.append(blockAndListID))) {
+    return false;
+  }
+  if (MOZ_UNLIKELY(!trailersRemoved_.append(nullptr))) {
+    trailersAdded_.popBack();
+    return false;
+  }
+
+  // This is a clone of the logic in ::registerMallocedBuffer.  It may be
+  // that some other heuristic is better, once we know more about the
+  // typical behaviour of wasm-GC applications.
+  trailerBytes_ += nBytes;
+  if (MOZ_UNLIKELY(trailerBytes_ > capacity() * 8)) {
+    requestMinorGC(JS::GCReason::NURSERY_TRAILERS);
+  }
+  return true;
+}
+
+inline void js::Nursery::unregisterTrailer(void* block) {
+  MOZ_ASSERT(trailersRemovedUsed_ < trailersRemoved_.length());
+  trailersRemoved_[trailersRemovedUsed_] = block;
+  trailersRemovedUsed_++;
+}
+
+namespace js {
+
+// The allocation methods below will not run the garbage collector. If the
+// nursery cannot accomodate the allocation, the malloc heap will be used
+// instead.
+
+template <typename T>
+static inline T* AllocateCellBuffer(JSContext* cx, gc::Cell* cell,
+                                    uint32_t count) {
+  size_t nbytes = RoundUp(count * sizeof(T), sizeof(Value));
+  auto* buffer = static_cast<T*>(cx->nursery().allocateBuffer(
+      cell->zone(), cell, nbytes, js::MallocArena));
+  if (!buffer) {
+    ReportOutOfMemory(cx);
+  }
+
+  return buffer;
+}
+
+// If this returns null then the old buffer will be left alone.
+template <typename T>
+static inline T* ReallocateCellBuffer(JSContext* cx, gc::Cell* cell,
+                                      T* oldBuffer, uint32_t oldCount,
+                                      uint32_t newCount, arena_id_t arenaId) {
+  size_t oldBytes = RoundUp(oldCount * sizeof(T), sizeof(Value));
+  size_t newBytes = RoundUp(newCount * sizeof(T), sizeof(Value));
+
+  T* buffer = static_cast<T*>(cx->nursery().reallocateBuffer(
+      cell->zone(), cell, oldBuffer, oldBytes, newBytes, arenaId));
+  if (!buffer) {
+    ReportOutOfMemory(cx);
+  }
+
+  return buffer;
+}
+
+}  // namespace js
+
+#endif /* gc_Nursery_inl_h */