Changeset 38632 in webkit for trunk/JavaScriptCore/parser/Lexer.h

Timestamp:

Nov 20, 2008, 2:27:34 PM (17 years ago)

Author:

[email protected]

Message:

2008-11-20 Sam Weinig <​[email protected]>

Reviewed by Geoffrey Garen.

Speedup the lexer to offset coming re-parsing patch.

• .6% progression on Sunspider.

• bytecompiler/SegmentedVector.h: (JSC::SegmentedVector::shrink): Fixed bug where m_size would not be set when shrinking to 0.

• parser/Lexer.cpp: (JSC::Lexer::Lexer): (JSC::Lexer::isIdentStart): Use isASCIIAlpha and isASCII to avoid going into ICU in the common cases. (JSC::Lexer::isIdentPart): Use isASCIIAlphanumeric and isASCII to avoid going into ICU in the common cases (JSC::isDecimalDigit): Use version in ASCIICType.h. Inlining it was a regression. (JSC::Lexer::isHexDigit): Ditto. (JSC::Lexer::isOctalDigit): Ditto. (JSC::Lexer::clear): Resize the m_identifiers SegmentedVector to initial capacity
• parser/Lexer.h: Remove unused m_strings vector. Make m_identifiers a SegmentedVector<Identifier> to avoid allocating a new Identifier* for each identifier found. The SegmentedVector is need so we can passes references to the Identifier to the parser, which remain valid even when the vector is resized. (JSC::Lexer::makeIdentifier): Inline and return a reference to the added Identifier.

File:

• trunk/JavaScriptCore/parser/Lexer.h (modified) (3 diffs)

trunk/JavaScriptCore/parser/Lexer.h

@@ -24 +24 @@
 #define Lexer_h
 
+#include "Identifier.h"
 #include "Lookup.h"
-#include "UString.h"
+#include "SegmentedVector.h"
+#include "SourceCode.h"
 #include <wtf/Vector.h>
-#include "SourceCode.h"
 
 namespace JSC {
 
-    class Identifier;
     class RegExp;
 
@@ -113 +113 @@
         void record16(UChar);
 
-        JSC::Identifier* makeIdentifier(const Vector<UChar>& buffer);
+        JSC::Identifier* makeIdentifier(const Vector<UChar>& buffer)
+        {
+            m_identifiers.append(JSC::Identifier(m_globalData, buffer.data(), buffer.size()));
+            return &m_identifiers.last();
+        }
+
+        static const size_t initialReadBufferCapacity = 32;
+        static const size_t initialIdentifierTableCapacity = 64;
 
         int yylineno;
@@ -149 +156 @@
         int m_nextOffset3;
         
-        Vector<UString*> m_strings;
-        Vector<JSC::Identifier*> m_identifiers;
+        SegmentedVector<JSC::Identifier, initialIdentifierTableCapacity> m_identifiers;
 
         JSGlobalData* m_globalData;