From: drh <>
Date: Wed, 19 Jul 2023 17:24:36 +0000 (+0000)
Subject: Further improvement to JSON parser performance.
X-Git-Tag: version-3.43.0~126^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=50834d8b74a88736dcf50e334197bcebe54b55ec;p=thirdparty%2Fsqlite.git

Further improvement to JSON parser performance.

FossilOrigin-Name: 144c8ccf6e5bb2527dd98742f0d67e0a16c627e7c67f754ce8ed4c4fb5b8d8b6
---

diff --git a/manifest b/manifest
index 5c20d00512..140124f2f1 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Further\sperformance\senhancements\sto\sJSON\sparsing\sand\srendering.\s\sTotal\nperformance\sgain\sfor\slarge\sJSONs\sso\sfar\son\sthis\sbranch\sis\sabout\s11%.
-D 2023-07-19T15:06:29.535
+C Further\simprovement\sto\sJSON\sparser\sperformance.
+D 2023-07-19T17:24:36.452
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -597,7 +597,7 @@ F src/hash.h 3340ab6e1d13e725571d7cee6d3e3135f0779a7d8e76a9ce0a85971fa3953c51
 F src/hwtime.h f9c2dfb84dce7acf95ce6d289e46f5f9d3d1afd328e53da8f8e9008e3b3caae6
 F src/in-operator.md 10cd8f4bcd225a32518407c2fb2484089112fd71
 F src/insert.c 3f0a94082d978bbdd33c38fefea15346c6c6bffb70bc645a71dc0f1f87dd3276
-F src/json.c 4a875e61ce6aa869bd6028836f198e7ab08d3efceb8ab8d0529bec8061b67e94
+F src/json.c e48136fce64e5004b1b8be76624cc9a4ac9ff6ae630a97df187c0ea4b9692d1b
 F src/legacy.c d7874bc885906868cd51e6c2156698f2754f02d9eee1bae2d687323c3ca8e5aa
 F src/loadext.c 176d6b2cb18a6ad73b133db17f6fc351c4d9a2d510deebdb76c22bde9cfd1465
 F src/main.c 512b1d45bc556edf4471a845afb7ba79e64bd5b832ab222dc195c469534cd002
@@ -2043,8 +2043,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P c9fbe0185cd5d64950724b00cd0bfb3a7939a985040465a0f35f445acb6e94a6
-R dbdd171b9775d82e33a4a9295a6ddced
+P adb4d6b007cbe9d7c9670f5fc196443ebe0f3a89df1f3290ba6247fcf83fe5bd
+R ab82eb710f468841d4023aaae186be2d
 U drh
-Z 04400ecbf8a4a25997341f5b2d7f0282
+Z d9c18383c20eeea0feca70f3dd0775a9
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index 7057be53c2..4a7e995a3f 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-adb4d6b007cbe9d7c9670f5fc196443ebe0f3a89df1f3290ba6247fcf83fe5bd
\ No newline at end of file
+144c8ccf6e5bb2527dd98742f0d67e0a16c627e7c67f754ce8ed4c4fb5b8d8b6
\ No newline at end of file
diff --git a/src/json.c b/src/json.c
index ed43a5ce96..176dcbfdb9 100644
--- a/src/json.c
+++ b/src/json.c
@@ -1272,8 +1272,30 @@ json_parse_restart:
   parse_string:
     cDelim = z[i];
     for(j=i+1; 1; j++){
-      unsigned char uc = (unsigned char)z[j];
-      if( uc=='\\' ){
+      static const char aOk[256] = {
+      	  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
+      	  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
+      	  1, 1, 0, 1, 1, 1, 1, 0,  1, 1, 1, 1, 1, 1, 1, 1,
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 0, 1, 1, 1,
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
+
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
+      	  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1
+      };
+      if( aOk[(unsigned char)z[j]] ) continue;
+      c = z[j];
+      if( c==cDelim ){
+        break;
+      }else if( c=='\\' ){
         c = z[++j];
         if( c=='"' || c=='\\' || c=='/' || c=='b' || c=='f'
            || c=='n' || c=='r' || c=='t'
@@ -1293,11 +1315,7 @@ json_parse_restart:
           pParse->iErr = j;
           return -1;
         }
-      }else if( uc>'\'' ){
-        continue;
-      }else if( uc==cDelim ){
-        break;
-      }else if( uc<=0x1f ){
+      }else if( c<=0x1f ){
         /* Control characters are not allowed in strings */
         pParse->iErr = j;
         return -1;