Diff
Modified: trunk/Source/_javascript_Core/ChangeLog (183987 => 183988)
--- trunk/Source/_javascript_Core/ChangeLog 2015-05-08 08:04:07 UTC (rev 183987)
+++ trunk/Source/_javascript_Core/ChangeLog 2015-05-08 08:44:23 UTC (rev 183988)
@@ -1,3 +1,27 @@
+2015-05-08 Andreas Kling <[email protected]>
+
+ Optimize serialization of quoted JSON strings.
+ <https://webkit.org/b/144754>
+
+ Reviewed by Darin Adler.
+
+ Optimized the serialization of quoted strings into JSON by moving the logic into
+ StringBuilder so it can make smarter decisions about buffering.
+
+ 12% progression on Kraken/json-stringify-tinderbox (on my Mac Pro.)
+
+ * bytecompiler/NodesCodegen.cpp:
+ (JSC::ObjectPatternNode::toString): Use the new StringBuilder API.
+
+ * runtime/JSONObject.h:
+ * runtime/JSONObject.cpp:
+ (JSC::Stringifier::Holder::appendNextProperty):
+ (JSC::appendStringToStringBuilder): Deleted.
+ (JSC::appendQuotedJSONStringToBuilder): Deleted.
+ (JSC::Stringifier::appendQuotedString): Deleted.
+ (JSC::Stringifier::appendStringifiedValue): Moved the bulk of this logic
+ to StringBuilder and call that from here.
+
2015-05-07 Commit Queue <[email protected]>
Unreviewed, rolling out r183961.
Modified: trunk/Source/_javascript_Core/bytecompiler/NodesCodegen.cpp (183987 => 183988)
--- trunk/Source/_javascript_Core/bytecompiler/NodesCodegen.cpp 2015-05-08 08:04:07 UTC (rev 183987)
+++ trunk/Source/_javascript_Core/bytecompiler/NodesCodegen.cpp 2015-05-08 08:44:23 UTC (rev 183988)
@@ -3087,7 +3087,7 @@
builder.append('{');
for (size_t i = 0; i < m_targetPatterns.size(); i++) {
if (m_targetPatterns[i].wasString)
- appendQuotedJSONStringToBuilder(builder, m_targetPatterns[i].propertyName.string());
+ builder.appendQuotedJSONString(m_targetPatterns[i].propertyName.string());
else
builder.append(m_targetPatterns[i].propertyName.string());
builder.append(':');
Modified: trunk/Source/_javascript_Core/runtime/JSONObject.cpp (183987 => 183988)
--- trunk/Source/_javascript_Core/runtime/JSONObject.cpp 2015-05-08 08:04:07 UTC (rev 183987)
+++ trunk/Source/_javascript_Core/runtime/JSONObject.cpp 2015-05-08 08:44:23 UTC (rev 183988)
@@ -107,8 +107,6 @@
friend class Holder;
- static void appendQuotedString(StringBuilder&, const String&);
-
JSValue toJSON(JSValue, const PropertyNameForFunctionCall&);
enum StringifyResult { StringifyFailed, StringifySucceeded, StringifyFailedDueToUndefinedValue };
@@ -255,72 +253,6 @@
return Local<Unknown>(m_exec->vm(), jsString(m_exec, result.toString()));
}
-template <typename CharType>
-static void appendStringToStringBuilder(StringBuilder& builder, const CharType* data, int length)
-{
- for (int i = 0; i < length; ++i) {
- int start = i;
- while (i < length && (data[i] > 0x1F && data[i] != '"' && data[i] != '\\'))
- ++i;
- builder.append(data + start, i - start);
- if (i >= length)
- break;
- switch (data[i]) {
- case '\t':
- builder.append('\\');
- builder.append('t');
- break;
- case '\r':
- builder.append('\\');
- builder.append('r');
- break;
- case '\n':
- builder.append('\\');
- builder.append('n');
- break;
- case '\f':
- builder.append('\\');
- builder.append('f');
- break;
- case '\b':
- builder.append('\\');
- builder.append('b');
- break;
- case '"':
- builder.append('\\');
- builder.append('"');
- break;
- case '\\':
- builder.append('\\');
- builder.append('\\');
- break;
- default:
- static const char hexDigits[] = "0123456789abcdef";
- UChar ch = data[i];
- LChar hex[] = { '\\', 'u', static_cast<LChar>(hexDigits[(ch >> 12) & 0xF]), static_cast<LChar>(hexDigits[(ch >> 8) & 0xF]), static_cast<LChar>(hexDigits[(ch >> 4) & 0xF]), static_cast<LChar>(hexDigits[ch & 0xF]) };
- builder.append(hex, WTF_ARRAY_LENGTH(hex));
- break;
- }
- }
-}
-
-void appendQuotedJSONStringToBuilder(StringBuilder& builder, const String& message)
-{
- builder.append('"');
-
- if (message.is8Bit())
- appendStringToStringBuilder(builder, message.characters8(), message.length());
- else
- appendStringToStringBuilder(builder, message.characters16(), message.length());
-
- builder.append('"');
-}
-
-void Stringifier::appendQuotedString(StringBuilder& builder, const String& value)
-{
- appendQuotedJSONStringToBuilder(builder, value);
-}
-
inline JSValue Stringifier::toJSON(JSValue value, const PropertyNameForFunctionCall& propertyName)
{
ASSERT(!m_exec->hadException());
@@ -385,7 +317,7 @@
String stringValue;
if (value.getString(m_exec, stringValue)) {
- appendQuotedString(builder, stringValue);
+ builder.appendQuotedJSONString(stringValue);
return StringifySucceeded;
}
@@ -556,7 +488,7 @@
stringifier.startNewLine(builder);
// Append the property name.
- appendQuotedString(builder, propertyName.string());
+ builder.appendQuotedJSONString(propertyName.string());
builder.append(':');
if (stringifier.willIndent())
builder.append(' ');
Modified: trunk/Source/_javascript_Core/runtime/JSONObject.h (183987 => 183988)
--- trunk/Source/_javascript_Core/runtime/JSONObject.h 2015-05-08 08:04:07 UTC (rev 183987)
+++ trunk/Source/_javascript_Core/runtime/JSONObject.h 2015-05-08 08:44:23 UTC (rev 183988)
@@ -62,8 +62,6 @@
JS_EXPORT_PRIVATE JSValue JSONParse(ExecState*, const String&);
JS_EXPORT_PRIVATE String JSONStringify(ExecState*, JSValue, unsigned indent);
-JS_EXPORT_PRIVATE void appendQuotedJSONStringToBuilder(StringBuilder&, const String&);
-
} // namespace JSC
Modified: trunk/Source/WTF/ChangeLog (183987 => 183988)
--- trunk/Source/WTF/ChangeLog 2015-05-08 08:04:07 UTC (rev 183987)
+++ trunk/Source/WTF/ChangeLog 2015-05-08 08:44:23 UTC (rev 183988)
@@ -1,3 +1,31 @@
+2015-05-08 Andreas Kling <[email protected]>
+
+ Optimize serialization of quoted JSON strings.
+ <https://webkit.org/b/144754>
+
+ Reviewed by Darin Adler.
+
+ Add a StringBuilder API for appending a quoted JSON string. This is used by
+ JSON.stringify() to implement efficient appending of strings while escaping
+ quotes, control characters and \uNNNN-style characters.
+
+ The main benefit comes from only doing a single buffer expansion up front,
+ instead of doing it every time we append something. The fudge factor is pretty
+ large, since the maximum number of output characters per input character is 6.
+
+ The first landing of this patch had two bugs in it:
+
+ - Made \uNNNN escapes uppercase hexadecimal instead of lowercase.
+ - Didn't preallocate enough space for 8-bit input strings.
+
+ Both were caught by existing tests on our bots, and both were due to last-minute
+ changes before landing. :/
+
+ * wtf/text/StringBuilder.cpp:
+ (WTF::appendQuotedJSONStringInternal):
+ (WTF::StringBuilder::appendQuotedJSONString):
+ * wtf/text/StringBuilder.h:
+
2015-05-07 Commit Queue <[email protected]>
Unreviewed, rolling out r183961.
Modified: trunk/Source/WTF/wtf/text/StringBuilder.cpp (183987 => 183988)
--- trunk/Source/WTF/wtf/text/StringBuilder.cpp 2015-05-08 08:04:07 UTC (rev 183987)
+++ trunk/Source/WTF/wtf/text/StringBuilder.cpp 2015-05-08 08:44:23 UTC (rev 183988)
@@ -28,6 +28,7 @@
#include "StringBuilder.h"
#include "IntegerToStringConversion.h"
+#include "MathExtras.h"
#include "WTFString.h"
#include <wtf/dtoa.h>
@@ -360,4 +361,88 @@
}
}
+template <typename OutputCharacterType, typename InputCharacterType>
+static void appendQuotedJSONStringInternal(OutputCharacterType*& output, const InputCharacterType* input, unsigned length)
+{
+ for (const InputCharacterType* end = input + length; input != end; ++input) {
+ if (*input > 0x1F && *input != '"' && *input != '\\') {
+ *output++ = *input;
+ continue;
+ }
+ switch (*input) {
+ case '\t':
+ *output++ = '\\';
+ *output++ = 't';
+ break;
+ case '\r':
+ *output++ = '\\';
+ *output++ = 'r';
+ break;
+ case '\n':
+ *output++ = '\\';
+ *output++ = 'n';
+ break;
+ case '\f':
+ *output++ = '\\';
+ *output++ = 'f';
+ break;
+ case '\b':
+ *output++ = '\\';
+ *output++ = 'b';
+ break;
+ case '"':
+ *output++ = '\\';
+ *output++ = '"';
+ break;
+ case '\\':
+ *output++ = '\\';
+ *output++ = '\\';
+ break;
+ default:
+ ASSERT((*input & 0xFF00) == 0);
+ static const char hexDigits[] = "0123456789abcdef";
+ *output++ = '\\';
+ *output++ = 'u';
+ *output++ = '0';
+ *output++ = '0';
+ *output++ = static_cast<LChar>(hexDigits[(*input >> 4) & 0xF]);
+ *output++ = static_cast<LChar>(hexDigits[*input & 0xF]);
+ break;
+ }
+ }
+}
+
+void StringBuilder::appendQuotedJSONString(const String& string)
+{
+ // Make sure we have enough buffer space to append this string without having
+ // to worry about reallocating in the middle.
+ // The 2 is for the '"' quotes on each end.
+ // The 6 is for characters that need to be \uNNNN encoded.
+ size_t maximumCapacityRequired = length() + 2 + string.length() * 6;
+ RELEASE_ASSERT(maximumCapacityRequired < std::numeric_limits<unsigned>::max());
+
+ if (is8Bit() && !string.is8Bit())
+ allocateBufferUpConvert(m_bufferCharacters8, roundUpToPowerOfTwo(maximumCapacityRequired));
+ else
+ reserveCapacity(roundUpToPowerOfTwo(maximumCapacityRequired));
+
+ if (is8Bit()) {
+ ASSERT(string.is8Bit());
+ LChar* output = m_bufferCharacters8 + m_length;
+ *output++ = '"';
+ appendQuotedJSONStringInternal(output, string.characters8(), string.length());
+ *output++ = '"';
+ m_length = output - m_bufferCharacters8;
+ } else {
+ UChar* output = m_bufferCharacters16 + m_length;
+ *output++ = '"';
+ if (string.is8Bit())
+ appendQuotedJSONStringInternal(output, string.characters8(), string.length());
+ else
+ appendQuotedJSONStringInternal(output, string.characters16(), string.length());
+ *output++ = '"';
+ m_length = output - m_bufferCharacters16;
+ }
+}
+
} // namespace WTF
Modified: trunk/Source/WTF/wtf/text/StringBuilder.h (183987 => 183988)
--- trunk/Source/WTF/wtf/text/StringBuilder.h 2015-05-08 08:04:07 UTC (rev 183987)
+++ trunk/Source/WTF/wtf/text/StringBuilder.h 2015-05-08 08:44:23 UTC (rev 183988)
@@ -159,6 +159,8 @@
append(U16_TRAIL(c));
}
+ WTF_EXPORT_PRIVATE void appendQuotedJSONString(const String&);
+
template<unsigned charactersCount>
ALWAYS_INLINE void appendLiteral(const char (&characters)[charactersCount]) { append(characters, charactersCount - 1); }
Modified: trunk/Source/WebKit2/ChangeLog (183987 => 183988)
--- trunk/Source/WebKit2/ChangeLog 2015-05-08 08:04:07 UTC (rev 183987)
+++ trunk/Source/WebKit2/ChangeLog 2015-05-08 08:44:23 UTC (rev 183988)
@@ -1,3 +1,13 @@
+2015-05-08 Andreas Kling <[email protected]>
+
+ Optimize serialization of quoted JSON strings.
+ <https://webkit.org/b/144754>
+
+ Reviewed by Darin Adler.
+
+ * NetworkProcess/cache/NetworkCacheEntry.cpp:
+ (WebKit::NetworkCache::Entry::asJSON): Use the new StringBuilder API.
+
2015-05-08 Commit Queue <[email protected]>
Unreviewed, rolling out r183945.
Modified: trunk/Source/WebKit2/NetworkProcess/cache/NetworkCacheEntry.cpp (183987 => 183988)
--- trunk/Source/WebKit2/NetworkProcess/cache/NetworkCacheEntry.cpp 2015-05-08 08:04:07 UTC (rev 183987)
+++ trunk/Source/WebKit2/NetworkProcess/cache/NetworkCacheEntry.cpp 2015-05-08 08:44:23 UTC (rev 183988)
@@ -30,7 +30,6 @@
#include "NetworkCacheCoders.h"
#include "NetworkCacheDecoder.h"
#include "NetworkCacheEncoder.h"
-#include <_javascript_Core/JSONObject.h>
#include <WebCore/ResourceRequest.h>
#include <WebCore/SharedBuffer.h>
#include <wtf/text/StringBuilder.h>
@@ -159,7 +158,7 @@
{
json.appendLiteral("{\n");
json.appendLiteral("\"hash\": ");
- JSC::appendQuotedJSONStringToBuilder(json, m_key.hashAsString());
+ json.appendQuotedJSONString(m_key.hashAsString());
json.appendLiteral(",\n");
json.appendLiteral("\"bodySize\": ");
json.appendNumber(info.bodySize);
@@ -168,16 +167,16 @@
json.appendNumber(info.worth);
json.appendLiteral(",\n");
json.appendLiteral("\"partition\": ");
- JSC::appendQuotedJSONStringToBuilder(json, m_key.partition());
+ json.appendQuotedJSONString(m_key.partition());
json.appendLiteral(",\n");
json.appendLiteral("\"timestamp\": ");
json.appendNumber(std::chrono::duration_cast<std::chrono::milliseconds>(m_timeStamp.time_since_epoch()).count());
json.appendLiteral(",\n");
json.appendLiteral("\"URL\": ");
- JSC::appendQuotedJSONStringToBuilder(json, m_response.url().string());
+ json.appendQuotedJSONString(m_response.url().string());
json.appendLiteral(",\n");
json.appendLiteral("\"bodyHash\": ");
- JSC::appendQuotedJSONStringToBuilder(json, info.bodyHash);
+ json.appendQuotedJSONString(info.bodyHash);
json.appendLiteral(",\n");
json.appendLiteral("\"bodyShareCount\": ");
json.appendNumber(info.bodyShareCount);
@@ -189,9 +188,9 @@
json.appendLiteral(",\n");
firstHeader = false;
json.appendLiteral(" ");
- JSC::appendQuotedJSONStringToBuilder(json, header.key);
+ json.appendQuotedJSONString(header.key);
json.appendLiteral(": ");
- JSC::appendQuotedJSONStringToBuilder(json, header.value);
+ json.appendQuotedJSONString(header.value);
}
json.appendLiteral("\n}\n");
json.appendLiteral("}");
