Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

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

1 files changed, 526 insertions, 0 deletions

diff --git a/js/src/vm/StringType-inl.h b/js/src/vm/StringType-inl.h
new file mode 100644
index 0000000000..8abc944c40
--- /dev/null
+++ b/js/src/vm/StringType-inl.h
@@ -0,0 +1,526 @@
+/* -*- 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 vm_StringType_inl_h
+#define vm_StringType_inl_h
+
+#include "vm/StringType.h"
+
+#include "mozilla/PodOperations.h"
+#include "mozilla/Range.h"
+
+#include "gc/Allocator.h"
+#include "gc/MaybeRooted.h"
+#include "gc/StoreBuffer.h"
+#include "js/UniquePtr.h"
+#include "vm/JSContext.h"
+#include "vm/StaticStrings.h"
+
+#include "gc/GCContext-inl.h"
+#include "gc/StoreBuffer-inl.h"
+
+namespace js {
+
+// Allocate a thin inline string if possible, and a fat inline string if not.
+template <AllowGC allowGC, typename CharT>
+static MOZ_ALWAYS_INLINE JSInlineString* AllocateInlineString(
+    JSContext* cx, size_t len, CharT** chars, js::gc::Heap heap) {
+  MOZ_ASSERT(JSInlineString::lengthFits<CharT>(len));
+
+  if (JSThinInlineString::lengthFits<CharT>(len)) {
+    return cx->newCell<JSThinInlineString, allowGC>(heap, len, chars);
+  }
+  return cx->newCell<JSFatInlineString, allowGC>(heap, len, chars);
+}
+
+template <typename CharT>
+static MOZ_ALWAYS_INLINE JSAtom* AllocateInlineAtom(JSContext* cx, size_t len,
+                                                    CharT** chars,
+                                                    js::HashNumber hash) {
+  MOZ_ASSERT(JSInlineString::lengthFits<CharT>(len));
+
+  if (JSThinInlineString::lengthFits<CharT>(len)) {
+    return cx->newCell<js::NormalAtom, js::NoGC>(len, chars, hash);
+  }
+  return cx->newCell<js::FatInlineAtom, js::NoGC>(len, chars, hash);
+}
+
+// Create a thin inline string if possible, and a fat inline string if not.
+template <AllowGC allowGC, typename CharT>
+static MOZ_ALWAYS_INLINE JSInlineString* NewInlineString(
+    JSContext* cx, mozilla::Range<const CharT> chars,
+    js::gc::Heap heap = js::gc::Heap::Default) {
+  /*
+   * Don't bother trying to find a static atom; measurement shows that not
+   * many get here (for one, Atomize is catching them).
+   */
+
+  size_t len = chars.length();
+  CharT* storage;
+  JSInlineString* str = AllocateInlineString<allowGC>(cx, len, &storage, heap);
+  if (!str) {
+    return nullptr;
+  }
+
+  mozilla::PodCopy(storage, chars.begin().get(), len);
+  return str;
+}
+
+template <typename CharT>
+static MOZ_ALWAYS_INLINE JSAtom* NewInlineAtom(JSContext* cx,
+                                               const CharT* chars,
+                                               size_t length,
+                                               js::HashNumber hash) {
+  CharT* storage;
+  JSAtom* str = AllocateInlineAtom(cx, length, &storage, hash);
+  if (!str) {
+    return nullptr;
+  }
+
+  mozilla::PodCopy(storage, chars, length);
+  return str;
+}
+
+// Create a thin inline string if possible, and a fat inline string if not.
+template <typename CharT>
+static MOZ_ALWAYS_INLINE JSInlineString* NewInlineString(
+    JSContext* cx, Handle<JSLinearString*> base, size_t start, size_t length,
+    js::gc::Heap heap) {
+  MOZ_ASSERT(JSInlineString::lengthFits<CharT>(length));
+
+  CharT* chars;
+  JSInlineString* s = AllocateInlineString<CanGC>(cx, length, &chars, heap);
+  if (!s) {
+    return nullptr;
+  }
+
+  JS::AutoCheckCannotGC nogc;
+  mozilla::PodCopy(chars, base->chars<CharT>(nogc) + start, length);
+  return s;
+}
+
+template <typename CharT>
+static MOZ_ALWAYS_INLINE JSLinearString* TryEmptyOrStaticString(
+    JSContext* cx, const CharT* chars, size_t n) {
+  // Measurements on popular websites indicate empty strings are pretty common
+  // and most strings with length 1 or 2 are in the StaticStrings table. For
+  // length 3 strings that's only about 1%, so we check n <= 2.
+  if (n <= 2) {
+    if (n == 0) {
+      return cx->emptyString();
+    }
+
+    if (JSLinearString* str = cx->staticStrings().lookup(chars, n)) {
+      return str;
+    }
+  }
+
+  return nullptr;
+}
+
+} /* namespace js */
+
+MOZ_ALWAYS_INLINE bool JSString::validateLength(JSContext* maybecx,
+                                                size_t length) {
+  return validateLengthInternal<js::CanGC>(maybecx, length);
+}
+
+template <js::AllowGC allowGC>
+MOZ_ALWAYS_INLINE bool JSString::validateLengthInternal(JSContext* maybecx,
+                                                        size_t length) {
+  if (MOZ_UNLIKELY(length > JSString::MAX_LENGTH)) {
+    if constexpr (allowGC) {
+      js::ReportOversizedAllocation(maybecx, JSMSG_ALLOC_OVERFLOW);
+    }
+    return false;
+  }
+
+  return true;
+}
+
+template <>
+MOZ_ALWAYS_INLINE const char16_t* JSString::nonInlineCharsRaw() const {
+  return d.s.u2.nonInlineCharsTwoByte;
+}
+
+template <>
+MOZ_ALWAYS_INLINE const JS::Latin1Char* JSString::nonInlineCharsRaw() const {
+  return d.s.u2.nonInlineCharsLatin1;
+}
+
+inline JSRope::JSRope(JSString* left, JSString* right, size_t length) {
+  // JITs expect rope children aren't empty.
+  MOZ_ASSERT(!left->empty() && !right->empty());
+
+  if (left->hasLatin1Chars() && right->hasLatin1Chars()) {
+    setLengthAndFlags(length, INIT_ROPE_FLAGS | LATIN1_CHARS_BIT);
+  } else {
+    setLengthAndFlags(length, INIT_ROPE_FLAGS);
+  }
+  d.s.u2.left = left;
+  d.s.u3.right = right;
+
+  // Post-barrier by inserting into the whole cell buffer if either
+  // this -> left or this -> right is a tenured -> nursery edge.
+  if (isTenured()) {
+    js::gc::StoreBuffer* sb = left->storeBuffer();
+    if (!sb) {
+      sb = right->storeBuffer();
+    }
+    if (sb) {
+      sb->putWholeCell(this);
+    }
+  }
+}
+
+template <js::AllowGC allowGC>
+MOZ_ALWAYS_INLINE JSRope* JSRope::new_(
+    JSContext* cx,
+    typename js::MaybeRooted<JSString*, allowGC>::HandleType left,
+    typename js::MaybeRooted<JSString*, allowGC>::HandleType right,
+    size_t length, js::gc::Heap heap) {
+  if (MOZ_UNLIKELY(!validateLengthInternal<allowGC>(cx, length))) {
+    return nullptr;
+  }
+  return cx->newCell<JSRope, allowGC>(heap, left, right, length);
+}
+
+inline JSDependentString::JSDependentString(JSLinearString* base, size_t start,
+                                            size_t length) {
+  MOZ_ASSERT(start + length <= base->length());
+  JS::AutoCheckCannotGC nogc;
+  if (base->hasLatin1Chars()) {
+    setLengthAndFlags(length, INIT_DEPENDENT_FLAGS | LATIN1_CHARS_BIT);
+    d.s.u2.nonInlineCharsLatin1 = base->latin1Chars(nogc) + start;
+  } else {
+    setLengthAndFlags(length, INIT_DEPENDENT_FLAGS);
+    d.s.u2.nonInlineCharsTwoByte = base->twoByteChars(nogc) + start;
+  }
+  d.s.u3.base = base;
+  if (isTenured() && !base->isTenured()) {
+    base->storeBuffer()->putWholeCell(this);
+  }
+}
+
+MOZ_ALWAYS_INLINE JSLinearString* JSDependentString::new_(
+    JSContext* cx, JSLinearString* baseArg, size_t start, size_t length,
+    js::gc::Heap heap) {
+  /*
+   * Try to avoid long chains of dependent strings. We can't avoid these
+   * entirely, however, due to how ropes are flattened.
+   */
+  if (baseArg->isDependent()) {
+    start += baseArg->asDependent().baseOffset();
+    baseArg = baseArg->asDependent().base();
+  }
+
+  MOZ_ASSERT(start + length <= baseArg->length());
+
+  /*
+   * Do not create a string dependent on inline chars from another string,
+   * both to avoid the awkward moving-GC hazard this introduces and because it
+   * is more efficient to immediately undepend here.
+   */
+  bool useInline = baseArg->hasTwoByteChars()
+                       ? JSInlineString::lengthFits<char16_t>(length)
+                       : JSInlineString::lengthFits<JS::Latin1Char>(length);
+  if (useInline) {
+    JS::Rooted<JSLinearString*> base(cx, baseArg);
+    return baseArg->hasLatin1Chars()
+               ? js::NewInlineString<JS::Latin1Char>(cx, base, start, length,
+                                                     heap)
+               : js::NewInlineString<char16_t>(cx, base, start, length, heap);
+  }
+
+  JSDependentString* str =
+      cx->newCell<JSDependentString, js::NoGC>(heap, baseArg, start, length);
+  if (str) {
+    return str;
+  }
+
+  JS::Rooted<JSLinearString*> base(cx, baseArg);
+  return cx->newCell<JSDependentString>(heap, base, start, length);
+}
+
+inline JSLinearString::JSLinearString(const char16_t* chars, size_t length) {
+  setLengthAndFlags(length, INIT_LINEAR_FLAGS);
+  // Check that the new buffer is located in the StringBufferArena
+  checkStringCharsArena(chars);
+  d.s.u2.nonInlineCharsTwoByte = chars;
+}
+
+inline JSLinearString::JSLinearString(const JS::Latin1Char* chars,
+                                      size_t length) {
+  setLengthAndFlags(length, INIT_LINEAR_FLAGS | LATIN1_CHARS_BIT);
+  // Check that the new buffer is located in the StringBufferArena
+  checkStringCharsArena(chars);
+  d.s.u2.nonInlineCharsLatin1 = chars;
+}
+
+void JSLinearString::disownCharsBecauseError() {
+  setLengthAndFlags(0, INIT_LINEAR_FLAGS | LATIN1_CHARS_BIT);
+  d.s.u2.nonInlineCharsLatin1 = nullptr;
+}
+
+template <js::AllowGC allowGC, typename CharT>
+MOZ_ALWAYS_INLINE JSLinearString* JSLinearString::new_(
+    JSContext* cx, js::UniquePtr<CharT[], JS::FreePolicy> chars, size_t length,
+    js::gc::Heap heap) {
+  if (MOZ_UNLIKELY(!validateLengthInternal<allowGC>(cx, length))) {
+    return nullptr;
+  }
+
+  return newValidLength<allowGC>(cx, std::move(chars), length, heap);
+}
+
+template <js::AllowGC allowGC, typename CharT>
+MOZ_ALWAYS_INLINE JSLinearString* JSLinearString::newValidLength(
+    JSContext* cx, js::UniquePtr<CharT[], JS::FreePolicy> chars, size_t length,
+    js::gc::Heap heap) {
+  MOZ_ASSERT(!cx->zone()->isAtomsZone());
+  JSLinearString* str =
+      cx->newCell<JSLinearString, allowGC>(heap, chars.get(), length);
+  if (!str) {
+    return nullptr;
+  }
+
+  if (!str->isTenured()) {
+    // If the following registration fails, the string is partially initialized
+    // and must be made valid, or its finalizer may attempt to free
+    // uninitialized memory.
+    if (!cx->runtime()->gc.nursery().registerMallocedBuffer(
+            chars.get(), length * sizeof(CharT))) {
+      str->disownCharsBecauseError();
+      if (allowGC) {
+        ReportOutOfMemory(cx);
+      }
+      return nullptr;
+    }
+  } else {
+    // This can happen off the main thread for the atoms zone.
+    cx->zone()->addCellMemory(str, length * sizeof(CharT),
+                              js::MemoryUse::StringContents);
+  }
+
+  (void)chars.release();
+  return str;
+}
+
+template <typename CharT>
+MOZ_ALWAYS_INLINE JSAtom* JSAtom::newValidLength(
+    JSContext* cx, js::UniquePtr<CharT[], JS::FreePolicy> chars, size_t length,
+    js::HashNumber hash) {
+  MOZ_ASSERT(validateLength(cx, length));
+  MOZ_ASSERT(cx->zone()->isAtomsZone());
+  JSAtom* str =
+      cx->newCell<js::NormalAtom, js::NoGC>(chars.get(), length, hash);
+  if (!str) {
+    return nullptr;
+  }
+  (void)chars.release();
+
+  MOZ_ASSERT(str->isTenured());
+  cx->zone()->addCellMemory(str, length * sizeof(CharT),
+                            js::MemoryUse::StringContents);
+
+  return str;
+}
+
+inline js::PropertyName* JSLinearString::toPropertyName(JSContext* cx) {
+#ifdef DEBUG
+  uint32_t dummy;
+  MOZ_ASSERT(!isIndex(&dummy));
+#endif
+  if (isAtom()) {
+    return asAtom().asPropertyName();
+  }
+  JSAtom* atom = js::AtomizeString(cx, this);
+  if (!atom) {
+    return nullptr;
+  }
+  return atom->asPropertyName();
+}
+
+template <js::AllowGC allowGC>
+MOZ_ALWAYS_INLINE JSThinInlineString* JSThinInlineString::new_(
+    JSContext* cx, js::gc::Heap heap) {
+  MOZ_ASSERT(!cx->zone()->isAtomsZone());
+  return cx->newCell<JSThinInlineString, allowGC>(heap);
+}
+
+template <js::AllowGC allowGC>
+MOZ_ALWAYS_INLINE JSFatInlineString* JSFatInlineString::new_(
+    JSContext* cx, js::gc::Heap heap) {
+  MOZ_ASSERT(!cx->zone()->isAtomsZone());
+  return cx->newCell<JSFatInlineString, allowGC>(heap);
+}
+
+inline JSThinInlineString::JSThinInlineString(size_t length,
+                                              JS::Latin1Char** chars) {
+  MOZ_ASSERT(lengthFits<JS::Latin1Char>(length));
+  setLengthAndFlags(length, INIT_THIN_INLINE_FLAGS | LATIN1_CHARS_BIT);
+  *chars = d.inlineStorageLatin1;
+}
+
+inline JSThinInlineString::JSThinInlineString(size_t length, char16_t** chars) {
+  MOZ_ASSERT(lengthFits<char16_t>(length));
+  setLengthAndFlags(length, INIT_THIN_INLINE_FLAGS);
+  *chars = d.inlineStorageTwoByte;
+}
+
+inline JSFatInlineString::JSFatInlineString(size_t length,
+                                            JS::Latin1Char** chars) {
+  MOZ_ASSERT(lengthFits<JS::Latin1Char>(length));
+  setLengthAndFlags(length, INIT_FAT_INLINE_FLAGS | LATIN1_CHARS_BIT);
+  *chars = d.inlineStorageLatin1;
+}
+
+inline JSFatInlineString::JSFatInlineString(size_t length, char16_t** chars) {
+  MOZ_ASSERT(lengthFits<char16_t>(length));
+  setLengthAndFlags(length, INIT_FAT_INLINE_FLAGS);
+  *chars = d.inlineStorageTwoByte;
+}
+
+inline JSExternalString::JSExternalString(
+    const char16_t* chars, size_t length,
+    const JSExternalStringCallbacks* callbacks) {
+  MOZ_ASSERT(callbacks);
+  setLengthAndFlags(length, EXTERNAL_FLAGS);
+  d.s.u2.nonInlineCharsTwoByte = chars;
+  d.s.u3.externalCallbacks = callbacks;
+}
+
+MOZ_ALWAYS_INLINE JSExternalString* JSExternalString::new_(
+    JSContext* cx, const char16_t* chars, size_t length,
+    const JSExternalStringCallbacks* callbacks) {
+  if (MOZ_UNLIKELY(!validateLength(cx, length))) {
+    return nullptr;
+  }
+  auto* str = cx->newCell<JSExternalString>(chars, length, callbacks);
+  if (!str) {
+    return nullptr;
+  }
+  size_t nbytes = length * sizeof(char16_t);
+
+  MOZ_ASSERT(str->isTenured());
+  js::AddCellMemory(str, nbytes, js::MemoryUse::StringContents);
+
+  return str;
+}
+
+inline js::NormalAtom::NormalAtom(size_t length, JS::Latin1Char** chars,
+                                  js::HashNumber hash)
+    : hash_(hash) {
+  MOZ_ASSERT(JSInlineString::lengthFits<JS::Latin1Char>(length));
+  setLengthAndFlags(length,
+                    INIT_THIN_INLINE_FLAGS | LATIN1_CHARS_BIT | ATOM_BIT);
+  *chars = d.inlineStorageLatin1;
+}
+
+inline js::NormalAtom::NormalAtom(size_t length, char16_t** chars,
+                                  js::HashNumber hash)
+    : hash_(hash) {
+  MOZ_ASSERT(JSInlineString::lengthFits<char16_t>(length));
+  setLengthAndFlags(length, INIT_THIN_INLINE_FLAGS | ATOM_BIT);
+  *chars = d.inlineStorageTwoByte;
+}
+
+inline js::NormalAtom::NormalAtom(const char16_t* chars, size_t length,
+                                  js::HashNumber hash)
+    : hash_(hash) {
+  setLengthAndFlags(length, INIT_LINEAR_FLAGS | ATOM_BIT);
+  // Check that the new buffer is located in the StringBufferArena
+  checkStringCharsArena(chars);
+  d.s.u2.nonInlineCharsTwoByte = chars;
+}
+
+inline js::NormalAtom::NormalAtom(const JS::Latin1Char* chars, size_t length,
+                                  js::HashNumber hash)
+    : hash_(hash) {
+  setLengthAndFlags(length, INIT_LINEAR_FLAGS | LATIN1_CHARS_BIT | ATOM_BIT);
+  // Check that the new buffer is located in the StringBufferArena
+  checkStringCharsArena(chars);
+  d.s.u2.nonInlineCharsLatin1 = chars;
+}
+
+inline js::FatInlineAtom::FatInlineAtom(size_t length, JS::Latin1Char** chars,
+                                        js::HashNumber hash)
+    : hash_(hash) {
+  MOZ_ASSERT(JSFatInlineString::lengthFits<JS::Latin1Char>(length));
+  setLengthAndFlags(length,
+                    INIT_FAT_INLINE_FLAGS | LATIN1_CHARS_BIT | ATOM_BIT);
+  *chars = d.inlineStorageLatin1;
+}
+
+inline js::FatInlineAtom::FatInlineAtom(size_t length, char16_t** chars,
+                                        js::HashNumber hash)
+    : hash_(hash) {
+  MOZ_ASSERT(JSFatInlineString::lengthFits<char16_t>(length));
+  setLengthAndFlags(length, INIT_FAT_INLINE_FLAGS | ATOM_BIT);
+  *chars = d.inlineStorageTwoByte;
+}
+
+inline JSLinearString* js::StaticStrings::getUnitStringForElement(
+    JSContext* cx, JSString* str, size_t index) {
+  MOZ_ASSERT(index < str->length());
+
+  char16_t c;
+  if (!str->getChar(cx, index, &c)) {
+    return nullptr;
+  }
+  if (c < UNIT_STATIC_LIMIT) {
+    return getUnit(c);
+  }
+  return js::NewInlineString<CanGC>(cx, mozilla::Range<const char16_t>(&c, 1),
+                                    js::gc::Heap::Default);
+}
+
+MOZ_ALWAYS_INLINE void JSString::finalize(JS::GCContext* gcx) {
+  /* FatInline strings are in a different arena. */
+  MOZ_ASSERT(getAllocKind() != js::gc::AllocKind::FAT_INLINE_STRING);
+  MOZ_ASSERT(getAllocKind() != js::gc::AllocKind::FAT_INLINE_ATOM);
+
+  if (isLinear()) {
+    asLinear().finalize(gcx);
+  } else {
+    MOZ_ASSERT(isRope());
+  }
+}
+
+inline void JSLinearString::finalize(JS::GCContext* gcx) {
+  MOZ_ASSERT(getAllocKind() != js::gc::AllocKind::FAT_INLINE_STRING);
+  MOZ_ASSERT(getAllocKind() != js::gc::AllocKind::FAT_INLINE_ATOM);
+
+  if (!isInline() && !isDependent()) {
+    gcx->free_(this, nonInlineCharsRaw(), allocSize(),
+               js::MemoryUse::StringContents);
+  }
+}
+
+inline void JSFatInlineString::finalize(JS::GCContext* gcx) {
+  MOZ_ASSERT(getAllocKind() == js::gc::AllocKind::FAT_INLINE_STRING);
+  MOZ_ASSERT(isInline());
+
+  // Nothing to do.
+}
+
+inline void js::FatInlineAtom::finalize(JS::GCContext* gcx) {
+  MOZ_ASSERT(JSString::isAtom());
+  MOZ_ASSERT(getAllocKind() == js::gc::AllocKind::FAT_INLINE_ATOM);
+
+  // Nothing to do.
+}
+
+inline void JSExternalString::finalize(JS::GCContext* gcx) {
+  MOZ_ASSERT(JSString::isExternal());
+
+  size_t nbytes = length() * sizeof(char16_t);
+  gcx->removeCellMemory(this, nbytes, js::MemoryUse::StringContents);
+
+  callbacks()->finalize(const_cast<char16_t*>(rawTwoByteChars()));
+}
+
+#endif /* vm_StringType_inl_h */