From 0ade2ddf23d75245e4e9f0783604ece21a12be79 Mon Sep 17 00:00:00 2001
From: Tom Tromey <tromey@redhat.com>
Date: Fri, 10 Mar 2006 00:39:49 +0000
Subject: [PATCH] re PR libgcj/23495 (java.lang.String.equals is suboptimal)
PR libgcj/23495:
* java/lang/natString.cc (_Jv_NewString): Use memcpy.
(equals): Use memcmp.
(contentEquals): Likewise.
(getChars): Use memcpy.
(toCharArray): Likewise.
(regionMatches): Use memcmp.
(regionMatches): Likewise.
(startsWith): Likewise.
(concat): Use memcpy.
(valueOf): Likewise.
From-SVN: r111919
---
libjava/ChangeLog | 14 +++++
libjava/java/lang/natString.cc | 94 +++++++++++++---------------------
2 files changed, 51 insertions(+), 57 deletions(-)
diff --git a/libjava/ChangeLog b/libjava/ChangeLog
index af25e325abba..2e09bccd1d44 100644
--- a/libjava/ChangeLog
+++ b/libjava/ChangeLog
@@ -1,3 +1,17 @@
+2006-03-09 Tom Tromey <tromey@redhat.com>
+
+ PR libgcj/23495:
+ * java/lang/natString.cc (_Jv_NewString): Use memcpy.
+ (equals): Use memcmp.
+ (contentEquals): Likewise.
+ (getChars): Use memcpy.
+ (toCharArray): Likewise.
+ (regionMatches): Use memcmp.
+ (regionMatches): Likewise.
+ (startsWith): Likewise.
+ (concat): Use memcpy.
+ (valueOf): Likewise.
+
2006-03-09 Tom Tromey <tromey@redhat.com>
* configure: Rebuilt.
diff --git a/libjava/java/lang/natString.cc b/libjava/java/lang/natString.cc
index 3f630812d5ef..f3f3e4d567b5 100644
--- a/libjava/java/lang/natString.cc
+++ b/libjava/java/lang/natString.cc
@@ -409,8 +409,7 @@ _Jv_NewString(const jchar *chars, jsize len)
{
jstring str = _Jv_AllocString(len);
jchar* data = JvGetStringChars (str);
- while (--len >= 0)
- *data++ = *chars++;
+ memcpy (data, chars, len * sizeof (jchar));
return str;
}
@@ -534,16 +533,20 @@ java::lang::String::equals(jobject anObject)
jstring other = (jstring) anObject;
if (count != other->count)
return false;
- /* if both are interned, return false. */
- jint i = count;
+
+ // If both have cached hash codes, check that. If the cached hash
+ // codes are zero, don't bother trying to compute them.
+ int myHash = cachedHashCode;
+ int otherHash = other->cachedHashCode;
+ if (myHash && otherHash && myHash != otherHash)
+ return false;
+
+ // We could see if both are interned, and return false. But that
+ // seems too expensive.
+
jchar *xptr = JvGetStringChars (this);
jchar *yptr = JvGetStringChars (other);
- while (--i >= 0)
- {
- if (*xptr++ != *yptr++)
- return false;
- }
- return true;
+ return ! memcmp (xptr, yptr, count * sizeof (jchar));
}
jboolean
@@ -556,13 +559,9 @@ java::lang::String::contentEquals(java::lang::StringBuffer* buffer)
return false;
if (data == buffer->value)
return true; // Possible if shared.
- jint i = count;
jchar *xptr = JvGetStringChars(this);
jchar *yptr = elements(buffer->value);
- while (--i >= 0)
- if (*xptr++ != *yptr++)
- return false;
- return true;
+ return ! memcmp (xptr, yptr, count * sizeof (jchar));
}
jboolean
@@ -599,9 +598,8 @@ java::lang::String::getChars(jint srcBegin, jint srcEnd,
throw new ArrayIndexOutOfBoundsException;
jchar *dPtr = elements (dst) + dstBegin;
jchar *sPtr = JvGetStringChars (this) + srcBegin;
- jint i = srcEnd-srcBegin;
- while (--i >= 0)
- *dPtr++ = *sPtr++;
+ jint i = srcEnd - srcBegin;
+ memcpy (dPtr, sPtr, i * sizeof (jchar));
}
jbyteArray
@@ -666,8 +664,7 @@ java::lang::String::toCharArray()
jchar *dPtr = elements (array);
jchar *sPtr = JvGetStringChars (this);
jint i = count;
- while (--i >= 0)
- *dPtr++ = *sPtr++;
+ memcpy (dPtr, sPtr, i * sizeof (jchar));
return array;
}
@@ -704,12 +701,7 @@ java::lang::String::regionMatches (jint toffset,
jchar *tptr = JvGetStringChars (this) + toffset;
jchar *optr = JvGetStringChars (other) + ooffset;
jint i = len;
- while (--i >= 0)
- {
- if (*tptr++ != *optr++)
- return false;
- }
- return true;
+ return ! memcmp (tptr, optr, i * sizeof (jchar));
}
jint
@@ -742,25 +734,20 @@ java::lang::String::regionMatches (jboolean ignoreCase, jint toffset,
jchar *optr = JvGetStringChars (other) + ooffset;
jint i = len;
if (ignoreCase)
- while (--i >= 0)
- {
- jchar tch = *tptr++;
- jchar och = *optr++;
- if ((java::lang::Character::toLowerCase (tch)
- != java::lang::Character::toLowerCase (och))
- && (java::lang::Character::toUpperCase (tch)
- != java::lang::Character::toUpperCase (och)))
- return false;
- }
- else
- while (--i >= 0)
- {
- jchar tch = *tptr++;
- jchar och = *optr++;
- if (tch != och)
- return false;
- }
- return true;
+ {
+ while (--i >= 0)
+ {
+ jchar tch = *tptr++;
+ jchar och = *optr++;
+ if ((java::lang::Character::toLowerCase (tch)
+ != java::lang::Character::toLowerCase (och))
+ && (java::lang::Character::toUpperCase (tch)
+ != java::lang::Character::toUpperCase (och)))
+ return false;
+ }
+ return true;
+ }
+ return ! memcmp (tptr, optr, i * sizeof (jchar));
}
jboolean
@@ -771,12 +758,7 @@ java::lang::String::startsWith (jstring prefix, jint toffset)
return false;
jchar *xptr = JvGetStringChars (this) + toffset;
jchar *yptr = JvGetStringChars (prefix);
- while (--i >= 0)
- {
- if (*xptr++ != *yptr++)
- return false;
- }
- return true;
+ return ! memcmp (xptr, yptr, i * sizeof (jchar));
}
jint
@@ -868,12 +850,11 @@ java::lang::String::concat(jstring str)
jchar *dstPtr = JvGetStringChars(result);
jchar *srcPtr = JvGetStringChars(this);
jint i = count;
- while (--i >= 0)
- *dstPtr++ = *srcPtr++;
+ memcpy (dstPtr, srcPtr, i * sizeof (jchar));
+ dstPtr += i;
srcPtr = JvGetStringChars(str);
i = str->count;
- while (--i >= 0)
- *dstPtr++ = *srcPtr++;
+ memcpy (dstPtr, srcPtr, i * sizeof (jchar));
return result;
}
@@ -1048,8 +1029,7 @@ java::lang::String::valueOf(jcharArray data, jint offset, jint count)
jstring result = JvAllocString(count);
jchar *sPtr = elements (data) + offset;
jchar *dPtr = JvGetStringChars(result);
- while (--count >= 0)
- *dPtr++ = *sPtr++;
+ memcpy (dPtr, sPtr, count * sizeof (jchar));
return result;
}
--
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