import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

js/src/jsatominlines.h

@@ -0,0 +1,221 @@
+/* -*- 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 jsatominlines_h
+#define jsatominlines_h
+
+#include "jsatom.h"
+
+#include "mozilla/PodOperations.h"
+#include "mozilla/RangedPtr.h"
+
+#include "jscntxt.h"
+#include "jsnum.h"
+
+#include "vm/String.h"
+
+inline JSAtom*
+js::AtomStateEntry::asPtr(js::ExclusiveContext* cx) const
+{
+    JSAtom* atom = asPtrUnbarriered();
+    if (cx->isJSContext())
+        JSString::readBarrier(atom);
+    return atom;
+}
+
+inline JSAtom*
+js::AtomStateEntry::asPtrUnbarriered() const
+{
+    MOZ_ASSERT(bits != 0);
+    return reinterpret_cast<JSAtom*>(bits & NO_TAG_MASK);
+}
+
+namespace js {
+
+inline jsid
+AtomToId(JSAtom* atom)
+{
+    JS_STATIC_ASSERT(JSID_INT_MIN == 0);
+
+    uint32_t index;
+    if (atom->isIndex(&index) && index <= JSID_INT_MAX)
+        return INT_TO_JSID(int32_t(index));
+
+    return JSID_FROM_BITS(size_t(atom));
+}
+
+inline bool
+ValueToIdPure(const Value& v, jsid* id)
+{
+    int32_t i;
+    if (ValueFitsInInt32(v, &i) && INT_FITS_IN_JSID(i)) {
+        *id = INT_TO_JSID(i);
+        return true;
+    }
+
+    if (js::IsSymbolOrSymbolWrapper(v)) {
+        *id = SYMBOL_TO_JSID(js::ToSymbolPrimitive(v));
+        return true;
+    }
+
+    if (!v.isString() || !v.toString()->isAtom())
+        return false;
+
+    *id = AtomToId(&v.toString()->asAtom());
+    return true;
+}
+
+template <AllowGC allowGC>
+inline bool
+ValueToId(ExclusiveContext* cx, typename MaybeRooted<Value, allowGC>::HandleType v,
+          typename MaybeRooted<jsid, allowGC>::MutableHandleType idp)
+{
+    int32_t i;
+    if (ValueFitsInInt32(v, &i) && INT_FITS_IN_JSID(i)) {
+        idp.set(INT_TO_JSID(i));
+        return true;
+    }
+
+    if (js::IsSymbolOrSymbolWrapper(v)) {
+        idp.set(SYMBOL_TO_JSID(js::ToSymbolPrimitive(v)));
+        return true;
+    }
+
+    JSAtom* atom = ToAtom<allowGC>(cx, v);
+    if (!atom)
+        return false;
+
+    idp.set(AtomToId(atom));
+    return true;
+}
+
+/*
+ * Write out character representing |index| to the memory just before |end|.
+ * Thus |*end| is not touched, but |end[-1]| and earlier are modified as
+ * appropriate.  There must be at least js::UINT32_CHAR_BUFFER_LENGTH elements
+ * before |end| to avoid buffer underflow.  The start of the characters written
+ * is returned and is necessarily before |end|.
+ */
+template <typename T>
+inline mozilla::RangedPtr<T>
+BackfillIndexInCharBuffer(uint32_t index, mozilla::RangedPtr<T> end)
+{
+#ifdef DEBUG
+    /*
+     * Assert that the buffer we're filling will hold as many characters as we
+     * could write out, by dereferencing the index that would hold the most
+     * significant digit.
+     */
+    (void) *(end - UINT32_CHAR_BUFFER_LENGTH);
+#endif
+
+    do {
+        uint32_t next = index / 10, digit = index % 10;
+        *--end = '0' + digit;
+        index = next;
+    } while (index > 0);
+
+    return end;
+}
+
+bool
+IndexToIdSlow(ExclusiveContext* cx, uint32_t index, MutableHandleId idp);
+
+inline bool
+IndexToId(ExclusiveContext* cx, uint32_t index, MutableHandleId idp)
+{
+    if (index <= JSID_INT_MAX) {
+        idp.set(INT_TO_JSID(index));
+        return true;
+    }
+
+    return IndexToIdSlow(cx, index, idp);
+}
+
+static MOZ_ALWAYS_INLINE JSFlatString*
+IdToString(JSContext* cx, jsid id)
+{
+    if (JSID_IS_STRING(id))
+        return JSID_TO_ATOM(id);
+
+    if (MOZ_LIKELY(JSID_IS_INT(id)))
+        return Int32ToString<CanGC>(cx, JSID_TO_INT(id));
+
+    RootedValue idv(cx, IdToValue(id));
+    JSString* str = ToStringSlow<CanGC>(cx, idv);
+    if (!str)
+        return nullptr;
+
+    return str->ensureFlat(cx);
+}
+
+inline
+AtomHasher::Lookup::Lookup(const JSAtom* atom)
+  : isLatin1(atom->hasLatin1Chars()), length(atom->length()), atom(atom)
+{
+    hash = atom->hash();
+    if (isLatin1) {
+        latin1Chars = atom->latin1Chars(nogc);
+        MOZ_ASSERT(mozilla::HashString(latin1Chars, length) == hash);
+    } else {
+        twoByteChars = atom->twoByteChars(nogc);
+        MOZ_ASSERT(mozilla::HashString(twoByteChars, length) == hash);
+    }
+}
+
+inline bool
+AtomHasher::match(const AtomStateEntry& entry, const Lookup& lookup)
+{
+    JSAtom* key = entry.asPtrUnbarriered();
+    if (lookup.atom)
+        return lookup.atom == key;
+    if (key->length() != lookup.length || key->hash() != lookup.hash)
+        return false;
+
+    if (key->hasLatin1Chars()) {
+        const Latin1Char* keyChars = key->latin1Chars(lookup.nogc);
+        if (lookup.isLatin1)
+            return mozilla::PodEqual(keyChars, lookup.latin1Chars, lookup.length);
+        return EqualChars(keyChars, lookup.twoByteChars, lookup.length);
+    }
+
+    const char16_t* keyChars = key->twoByteChars(lookup.nogc);
+    if (lookup.isLatin1)
+        return EqualChars(lookup.latin1Chars, keyChars, lookup.length);
+    return mozilla::PodEqual(keyChars, lookup.twoByteChars, lookup.length);
+}
+
+inline Handle<PropertyName*>
+TypeName(JSType type, const JSAtomState& names)
+{
+    MOZ_ASSERT(type < JSTYPE_LIMIT);
+    JS_STATIC_ASSERT(offsetof(JSAtomState, undefined) +
+                     JSTYPE_LIMIT * sizeof(ImmutablePropertyNamePtr) <=
+                     sizeof(JSAtomState));
+    JS_STATIC_ASSERT(JSTYPE_VOID == 0);
+    return (&names.undefined)[type];
+}
+
+inline Handle<PropertyName*>
+ClassName(JSProtoKey key, JSAtomState& atomState)
+{
+    MOZ_ASSERT(key < JSProto_LIMIT);
+    JS_STATIC_ASSERT(offsetof(JSAtomState, Null) +
+                     JSProto_LIMIT * sizeof(ImmutablePropertyNamePtr) <=
+                     sizeof(JSAtomState));
+    JS_STATIC_ASSERT(JSProto_Null == 0);
+    return (&atomState.Null)[key];
+}
+
+inline Handle<PropertyName*>
+ClassName(JSProtoKey key, ExclusiveContext* cx)
+{
+    return ClassName(key, cx->names());
+}
+
+} // namespace js
+
+#endif /* jsatominlines_h */