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Apply V8 r5951 to fix Mac build

From f3973972b727df480697443871d780596aba0201 Mon Sep 17 00:00:00 2001
From: erik.corry@gmail.com <erik.corry@gmail.com@ce2b1a6d-e550-0410-aec6-3dcde31c8c00>
Date: Wed, 8 Dec 2010 16:23:25 +0000
Subject: [PATCH] Speed up quoting of JSON strings by allocating a string that is big enough
 and then trimming it when the length is known.  This way we only have to
 traverse the input once.
 Review URL: http://codereview.chromium.org/5556012
v0.7.4-release
Ryan Dahl 14 years ago
parent
commit
32e8692b06
  1. 201
      deps/v8/src/runtime.cc
  2. 14
      deps/v8/src/spaces-inl.h
  3. 5
      deps/v8/src/spaces.h

201
deps/v8/src/runtime.cc

@ -4546,42 +4546,53 @@ static MaybeObject* Runtime_URIUnescape(Arguments args) {
static const unsigned int kQuoteTableLength = 128u;
static const char* const JsonQuotes[kQuoteTableLength] = {
"\\u0000", "\\u0001", "\\u0002", "\\u0003",
"\\u0004", "\\u0005", "\\u0006", "\\u0007",
"\\b", "\\t", "\\n", "\\u000b",
"\\f", "\\r", "\\u000e", "\\u000f",
"\\u0010", "\\u0011", "\\u0012", "\\u0013",
"\\u0014", "\\u0015", "\\u0016", "\\u0017",
"\\u0018", "\\u0019", "\\u001a", "\\u001b",
"\\u001c", "\\u001d", "\\u001e", "\\u001f",
NULL, NULL, "\\\"", NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
"\\\\", NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
};
static const int kJsonQuotesCharactersPerEntry = 8;
static const char* const JsonQuotes =
"\\u0000 \\u0001 \\u0002 \\u0003 "
"\\u0004 \\u0005 \\u0006 \\u0007 "
"\\b \\t \\n \\u000b "
"\\f \\r \\u000e \\u000f "
"\\u0010 \\u0011 \\u0012 \\u0013 "
"\\u0014 \\u0015 \\u0016 \\u0017 "
"\\u0018 \\u0019 \\u001a \\u001b "
"\\u001c \\u001d \\u001e \\u001f "
" ! \\\" # "
"$ % & ' "
"( ) * + "
", - . / "
"0 1 2 3 "
"4 5 6 7 "
"8 9 : ; "
"< = > ? "
"@ A B C "
"D E F G "
"H I J K "
"L M N O "
"P Q R S "
"T U V W "
"X Y Z [ "
"\\\\ ] ^ _ "
"` a b c "
"d e f g "
"h i j k "
"l m n o "
"p q r s "
"t u v w "
"x y z { "
"| } ~ \177 ";
// For a string that is less than 32k characters it should always be
// possible to allocate it in new space.
static const int kMaxGuaranteedNewSpaceString = 32 * 1024;
// Doing JSON quoting cannot make the string more than this many times larger.
static const int kJsonQuoteWorstCaseBlowup = 6;
// Covers the entire ASCII range (all other characters are unchanged by JSON
// quoting).
static const byte JsonQuoteLengths[kQuoteTableLength] = {
6, 6, 6, 6, 6, 6, 6, 6,
2, 2, 2, 6, 2, 2, 6, 6,
@ -4602,18 +4613,6 @@ static const byte JsonQuoteLengths[kQuoteTableLength] = {
};
template <typename Char>
Char* WriteString(Char* dst, const char* src_string) {
char c;
for (c = *src_string; c; c = *src_string) {
*dst = c;
dst++;
src_string++;
}
return dst;
}
template <typename StringType>
MaybeObject* AllocateRawString(int length);
@ -4631,58 +4630,104 @@ MaybeObject* AllocateRawString<SeqAsciiString>(int length) {
template <typename Char, typename StringType>
static MaybeObject* QuoteJsonString(Vector<const Char> characters) {
static MaybeObject* SlowQuoteJsonString(Vector<const Char> characters) {
int length = characters.length();
int quoted_length = 0;
for (int i = 0; i < length; i++) {
unsigned int c = characters[i];
if (sizeof(Char) > 1u) {
quoted_length += (c >= kQuoteTableLength) ? 1 : JsonQuoteLengths[c];
const Char* read_cursor = characters.start();
const Char* end = read_cursor + length;
const int kSpaceForQuotes = 2;
int quoted_length = kSpaceForQuotes;
while (read_cursor < end) {
Char c = *(read_cursor++);
if (sizeof(Char) > 1u && static_cast<unsigned>(c) >= kQuoteTableLength) {
quoted_length++;
} else {
quoted_length += JsonQuoteLengths[c];
quoted_length += JsonQuoteLengths[static_cast<unsigned>(c)];
}
}
Counters::quote_json_char_count.Increment(length);
// Add space for quotes.
quoted_length += 2;
MaybeObject* new_alloc = AllocateRawString<StringType>(quoted_length);
Object* new_object;
if (!new_alloc->ToObject(&new_object)) {
Counters::quote_json_char_recount.Increment(length);
return new_alloc;
}
StringType* new_string = StringType::cast(new_object);
Char* write_cursor = reinterpret_cast<Char*>(
new_string->address() + SeqAsciiString::kHeaderSize);
*(write_cursor++) = '"';
read_cursor = characters.start();
while (read_cursor < end) {
Char c = *(read_cursor++);
if (sizeof(Char) > 1u && static_cast<unsigned>(c) >= kQuoteTableLength) {
*(write_cursor++) = c;
} else {
int len = JsonQuoteLengths[static_cast<unsigned>(c)];
const char* replacement = JsonQuotes +
static_cast<unsigned>(c) * kJsonQuotesCharactersPerEntry;
for (int i = 0; i < len; i++) {
*write_cursor++ = *replacement++;
}
}
}
*(write_cursor++) = '"';
return new_string;
}
template <typename Char, typename StringType>
static MaybeObject* QuoteJsonString(Vector<const Char> characters) {
int length = characters.length();
Counters::quote_json_char_count.Increment(length);
const int kSpaceForQuotes = 2;
int worst_case_length = length * kJsonQuoteWorstCaseBlowup + kSpaceForQuotes;
if (worst_case_length > kMaxGuaranteedNewSpaceString) {
return SlowQuoteJsonString<Char, StringType>(characters);
}
MaybeObject* new_alloc = AllocateRawString<StringType>(worst_case_length);
Object* new_object;
if (!new_alloc->ToObject(&new_object)) {
return new_alloc;
}
StringType* new_string = StringType::cast(new_object);
ASSERT(Heap::new_space()->Contains(new_string));
STATIC_ASSERT(SeqTwoByteString::kHeaderSize == SeqAsciiString::kHeaderSize);
Char* write_cursor = reinterpret_cast<Char*>(
new_string->address() + SeqAsciiString::kHeaderSize);
*(write_cursor++) = '"';
const Char* read_cursor = characters.start();
if (quoted_length == length + 2) {
CopyChars(write_cursor, read_cursor, length);
write_cursor += length;
} else {
const Char* end = read_cursor + length;
while (read_cursor < end) {
Char c = *(read_cursor++);
if (sizeof(Char) > 1u && static_cast<unsigned>(c) >= kQuoteTableLength) {
*(write_cursor++) = c;
} else {
const char* replacement = JsonQuotes[static_cast<unsigned>(c)];
if (!replacement) {
*(write_cursor++) = c;
} else {
write_cursor = WriteString(write_cursor, replacement);
const Char* end = read_cursor + length;
while (read_cursor < end) {
Char c = *(read_cursor++);
if (sizeof(Char) > 1u && static_cast<unsigned>(c) >= kQuoteTableLength) {
*(write_cursor++) = c;
} else {
int len = JsonQuoteLengths[static_cast<unsigned>(c)];
const char* replacement = JsonQuotes +
static_cast<unsigned>(c) * kJsonQuotesCharactersPerEntry;
write_cursor[0] = replacement[0];
if (len > 1) {
write_cursor[1] = replacement[1];
if (len > 2) {
ASSERT(len == 6);
write_cursor[2] = replacement[2];
write_cursor[3] = replacement[3];
write_cursor[4] = replacement[4];
write_cursor[5] = replacement[5];
}
}
write_cursor += len;
}
}
*(write_cursor++) = '"';
ASSERT_EQ(SeqAsciiString::kHeaderSize + quoted_length * sizeof(Char),
reinterpret_cast<Address>(write_cursor) - new_string->address());
int final_length =
write_cursor - reinterpret_cast<Char*>(
new_string->address() + SeqAsciiString::kHeaderSize);
Heap::new_space()->ShrinkStringAtAllocationBoundary<StringType>(new_string,
final_length);
return new_string;
}

14
deps/v8/src/spaces-inl.h

@ -481,7 +481,7 @@ void LargeObjectChunk::Free(Executability executable) {
}
// -----------------------------------------------------------------------------
// LargeObjectSpace
// NewSpace
MaybeObject* NewSpace::AllocateRawInternal(int size_in_bytes,
AllocationInfo* alloc_info) {
@ -501,6 +501,18 @@ MaybeObject* NewSpace::AllocateRawInternal(int size_in_bytes,
}
template <typename StringType>
void NewSpace::ShrinkStringAtAllocationBoundary(String* string, int length) {
ASSERT(length <= string->length());
ASSERT(string->IsSeqString());
ASSERT(string->address() + StringType::SizeFor(string->length()) ==
allocation_info_.top);
allocation_info_.top =
string->address() + StringType::SizeFor(length);
string->set_length(length);
}
bool FreeListNode::IsFreeListNode(HeapObject* object) {
return object->map() == Heap::raw_unchecked_byte_array_map()
|| object->map() == Heap::raw_unchecked_one_pointer_filler_map()

5
deps/v8/src/spaces.h

@ -1643,6 +1643,11 @@ class NewSpace : public Space {
virtual bool ReserveSpace(int bytes);
// Resizes a sequential string which must be the most recent thing that was
// allocated in new space.
template <typename StringType>
inline void ShrinkStringAtAllocationBoundary(String* string, int len);
#ifdef ENABLE_HEAP_PROTECTION
// Protect/unprotect the space by marking it read-only/writable.
virtual void Protect();

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