From: drh <drh@noemail.net>
Date: Thu, 28 Apr 2016 18:53:08 +0000 (+0000)
Subject: Rearrange some code in the RowSet logic for clarity of presentation, while
X-Git-Tag: version-3.13.0~60
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=cb6d66becc06dd0ad293779e02b8b9b25dfe3301;p=thirdparty%2Fsqlite.git

Rearrange some code in the RowSet logic for clarity of presentation, while
adding an /*OPTIMIZATION-IF-TRUE*/ comment.  It should operate identically.

FossilOrigin-Name: 5748e64376c1c2be5154a632d1527cfebbb9ec74
---

diff --git a/manifest b/manifest
index 4e86475b14..0837962a87 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Use\scomments\sto\smark\sseveral\sbranches\sas\soptimizations.\s\sNo\schanges\sto\scode.
-D 2016-04-28T14:15:12.903
+C Rearrange\ssome\scode\sin\sthe\sRowSet\slogic\sfor\sclarity\sof\spresentation,\swhile\nadding\san\s/*OPTIMIZATION-IF-TRUE*/\scomment.\s\sIt\sshould\soperate\sidentically.
+D 2016-04-28T18:53:08.454
 F Makefile.in 9e816d0323e418fbc0f8b2c05fc14e0b3763d9e8
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 71b8b16cf9393f68e2e2035486ca104872558836
@@ -376,7 +376,7 @@ F src/prepare.c 22df6171aec1d86904ed2ad30c2348a5748aa04e
 F src/printf.c 63e6fb12bbe702dd664dc3703776c090383a5a26
 F src/random.c ba2679f80ec82c4190062d756f22d0c358180696
 F src/resolve.c b8f7174e5f8c33c44ded3a25a973d0bb89228c20
-F src/rowset.c 9fe4b3ad7cc00944386bb600233d8f523de07a6e
+F src/rowset.c d68d95e167cb234f51d655c9546f46752c9f6d45
 F src/select.c fd4a7ce2937497181063cfedb92058ac89491a5d
 F src/shell.c 14ff7f660530a52b117d110ba3390b7b2eb719b6
 F src/sqlite.h.in 9984129d86243424b765fcb3f147c697bd20bb54
@@ -1484,7 +1484,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P fcf85bfe50b254e825ee63a4cd0aa0b333b06eed
-R 197c644a6cd9b0806f84f77482d9fe15
+P 33e627472780b872716c504f2d585cc057c390a5
+R a33e3686da943dcb038124577baa15b4
 U drh
-Z 413f6650964e5d2ab342130728703294
+Z bac1d4beccda46e9aa1657c47d678425
diff --git a/manifest.uuid b/manifest.uuid
index abe023c752..976aebefbd 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-33e627472780b872716c504f2d585cc057c390a5
\ No newline at end of file
+5748e64376c1c2be5154a632d1527cfebbb9ec74
\ No newline at end of file
diff --git a/src/rowset.c b/src/rowset.c
index c2e73ed72e..65fcdb2318 100644
--- a/src/rowset.c
+++ b/src/rowset.c
@@ -338,20 +338,23 @@ static struct RowSetEntry *rowSetNDeepTree(
   if( *ppList==0 ){
     return 0;
   }
-  if( iDepth==1 ){
+  if( iDepth>1 ){   /*OPTIMIZATION-IF-TRUE*/
+    /* This branch cases a *balanced* tree to be generated.  A valid tree
+    ** is still generated without this branch, but it is wildly unbalanced
+    ** and inefficient. */
+    pLeft = rowSetNDeepTree(ppList, iDepth-1);
+    p = *ppList;
+    if( p==0 ){
+      return pLeft;
+    }
+    p->pLeft = pLeft;
+    *ppList = p->pRight;
+    p->pRight = rowSetNDeepTree(ppList, iDepth-1);
+  }else{
     p = *ppList;
     *ppList = p->pRight;
     p->pLeft = p->pRight = 0;
-    return p;
-  }
-  pLeft = rowSetNDeepTree(ppList, iDepth-1);
-  p = *ppList;
-  if( p==0 ){
-    return pLeft;
   }
-  p->pLeft = pLeft;
-  *ppList = p->pRight;
-  p->pRight = rowSetNDeepTree(ppList, iDepth-1);
   return p;
 }