From: drh <drh@noemail.net>
Date: Wed, 17 Jun 2015 13:20:54 +0000 (+0000)
Subject: Performance optimization and comment fixes for the LIKE and GLOB operators.
X-Git-Tag: version-3.8.11~158
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b0870486aa7da180d8d2554b30d0e973dc99dd20;p=thirdparty%2Fsqlite.git

Performance optimization and comment fixes for the LIKE and GLOB operators.

FossilOrigin-Name: c89d772628564a808173f6f73bc1798ec714276b
---

diff --git a/manifest b/manifest
index fc919c6ac0..e12a41f4ba 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Make\sgetCellInfo()\sa\sreal\sfunction\sinstead\sof\sa\smacro,\sfor\sa\ssize\sreduction\nand\sa\s0.2%\sperformance\sgain.
-D 2015-06-17T02:11:46.631
+C Performance\soptimization\sand\scomment\sfixes\sfor\sthe\sLIKE\sand\sGLOB\soperators.
+D 2015-06-17T13:20:54.580
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 1063c58075b7400d93326b0eb332b48a54f53025
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -205,7 +205,7 @@ F src/delete.c 8857a6f27560718f65d43bdbec86c967ae1f8dfa
 F src/expr.c fbde754df3fa10bbd3a1dcea08e77b0f1684d188
 F src/fault.c 160a0c015b6c2629d3899ed2daf63d75754a32bb
 F src/fkey.c c9b63a217d86582c22121699a47f22f524608869
-F src/func.c 5b8b8e77a0fb644eaf8947d413804622e32692b6
+F src/func.c a98ea5880dc50e9ca6dd6f57079a37b9cfcdecf1
 F src/global.c 4f77cadbc5427d00139ba43d0f3979804cbb700e
 F src/hash.c 4263fbc955f26c2e8cdc0cf214bc42435aa4e4f5
 F src/hash.h c8f3c31722cf3277d03713909761e152a5b81094
@@ -1286,7 +1286,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 48bd54594752d5be3337f12c72f28d2080cb630b
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 66d033b9c9a8c16b9a342be0b325bd85b8487c03
-R b009f7bdded8eda946c7f086260f521c
+P 55c393ea14197ae5fa56ebca7a47e7d980511fa7
+R 1acc9fb214636b090a14b1a72649aa22
 U drh
-Z e2dd593dbc0c1057f97a55b340af2663
+Z f92b296584755a34dfd3307b30aabfde
diff --git a/manifest.uuid b/manifest.uuid
index ea7a1a60de..5a2f7d0fdb 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-55c393ea14197ae5fa56ebca7a47e7d980511fa7
\ No newline at end of file
+c89d772628564a808173f6f73bc1798ec714276b
\ No newline at end of file
diff --git a/src/func.c b/src/func.c
index 62abf13d4d..d0565357d5 100644
--- a/src/func.c
+++ b/src/func.c
@@ -575,17 +575,15 @@ struct compareInfo {
 
 /*
 ** For LIKE and GLOB matching on EBCDIC machines, assume that every
-** character is exactly one byte in size.  Also, all characters are
-** able to participate in upper-case-to-lower-case mappings in EBCDIC
-** whereas only characters less than 0x80 do in ASCII.
+** character is exactly one byte in size.  Also, provde the Utf8Read()
+** macro for fast reading of the next character in the common case where
+** the next character is ASCII.
 */
 #if defined(SQLITE_EBCDIC)
 # define sqlite3Utf8Read(A)        (*((*A)++))
-# define GlobUpperToLower(A)       A = sqlite3UpperToLower[A]
-# define GlobUpperToLowerAscii(A)  A = sqlite3UpperToLower[A]
+# define Utf8Read(A)               (*(A++))
 #else
-# define GlobUpperToLower(A)       if( A<=0x7f ){ A = sqlite3UpperToLower[A]; }
-# define GlobUpperToLowerAscii(A)  A = sqlite3UpperToLower[A]
+# define Utf8Read(A)               (A[0]<0x80?*(A++):sqlite3Utf8Read(&A))
 #endif
 
 static const struct compareInfo globInfo = { '*', '?', '[', 0 };
@@ -627,7 +625,7 @@ static const struct compareInfo likeInfoAlt = { '%', '_',   0, 0 };
 **      Ec        Where E is the "esc" character and c is any other
 **                character, including '%', '_', and esc, match exactly c.
 **
-** The comments through this routine usually assume glob matching.
+** The comments within this routine usually assume glob matching.
 **
 ** This routine is usually quick, but can be N**2 in the worst case.
 */
@@ -651,13 +649,12 @@ static int patternCompare(
   */
   matchOther = esc ? esc : pInfo->matchSet;
 
-  while( (c = sqlite3Utf8Read(&zPattern))!=0 ){
+  while( (c = Utf8Read(zPattern))!=0 ){
     if( c==matchAll ){  /* Match "*" */
       /* Skip over multiple "*" characters in the pattern.  If there
       ** are also "?" characters, skip those as well, but consume a
       ** single character of the input string for each "?" skipped */
-      while( (c=sqlite3Utf8Read(&zPattern)) == matchAll
-               || c == matchOne ){
+      while( (c=Utf8Read(zPattern)) == matchAll || c == matchOne ){
         if( c==matchOne && sqlite3Utf8Read(&zString)==0 ){
           return 0;
         }
@@ -702,7 +699,7 @@ static int patternCompare(
           if( patternCompare(zPattern,zString,pInfo,esc) ) return 1;
         }
       }else{
-        while( (c2 = sqlite3Utf8Read(&zString))!=0 ){
+        while( (c2 = Utf8Read(zString))!=0 ){
           if( c2!=c ) continue;
           if( patternCompare(zPattern,zString,pInfo,esc) ) return 1;
         }
@@ -748,7 +745,7 @@ static int patternCompare(
         continue;
       }
     }
-    c2 = sqlite3Utf8Read(&zString);
+    c2 = Utf8Read(zString);
     if( c==c2 ) continue;
     if( noCase && c<0x80 && c2<0x80 && sqlite3Tolower(c)==sqlite3Tolower(c2) ){
       continue;