From 4efc4754f349772f883f2aef49fa272eb01cde84 Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Fri, 16 Jan 2004 15:55:37 +0000
Subject: [PATCH] Incremental code compaction in expr.c.  Now about 4% smaller.
 Lots more work to do. (CVS 1183)

FossilOrigin-Name: d292ba5148059dce3893b80eabdca4af9f75194e
---
 manifest        |  14 +++----
 manifest.uuid   |   2 +-
 src/expr.c      | 102 +++++++++++++++++++++++-------------------------
 src/sqliteInt.h |   6 ++-
 4 files changed, 62 insertions(+), 62 deletions(-)

diff --git a/manifest b/manifest
index 896ac5261a..4ce91d165f 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sa\sbuffer-overflow\sproblem\sin\sthe\srandStr\sfunction\s(used\sonly\sfor\stesting).\s(CVS\s1182)
-D 2004-01-16T13:58:18
+C Incremental\scode\scompaction\sin\sexpr.c.\s\sNow\sabout\s4%\ssmaller.\nLots\smore\swork\sto\sdo.\s(CVS\s1183)
+D 2004-01-16T15:55:38
 F Makefile.in 0515ff9218ad8d5a8f6220f0494b8ef94c67013b
 F Makefile.linux-gcc b86a99c493a5bfb402d1d9178dcdc4bd4b32f906
 F README f1de682fbbd94899d50aca13d387d1b3fd3be2dd
@@ -31,7 +31,7 @@ F src/copy.c 9e47975ea96751c658bcf1a0c4f0bb7c6ee61e73
 F src/date.c bb89fdb9c89e367b9a728c58cb96e4823974a2c1
 F src/delete.c 0f81e6799c089487615d38e042a2de4d2d6192bc
 F src/encode.c 9e70ea1e4e746f23f18180949e94f1bb1c2220d3
-F src/expr.c 866a6d7aacc2825aa13056ccbea1a16f436a1ca5
+F src/expr.c 5ecbce47b7f163bb1f64bc5e19fbb115ab468f98
 F src/func.c 564c0bbe93c290774b305c0199237b8e8bcbda53
 F src/hash.c 9b56ef3b291e25168f630d5643a4264ec011c70e
 F src/hash.h 3247573ab95b9dd90bcca0307a75d9a16da1ccc7
@@ -49,7 +49,7 @@ F src/random.c 19e8e00fe0df32a742f115773f57651be327cabe
 F src/select.c 2712bd4d311ebe7dbf8fd7596a809042657db85f
 F src/shell.c 3b067edc098c45caca164bcad1fa79192c3ec5ae
 F src/sqlite.h.in c70d8533cd5a5ae8af580597dbc726693ef82de9
-F src/sqliteInt.h 99df38d3c16cc727030c218a3fc61de08c071d08
+F src/sqliteInt.h c5b727d5d07b88654c204c0fc1ae79c9f635a008
 F src/table.c d845cb101b5afc1f7fea083c99e3d2fa7998d895
 F src/tclsqlite.c 85810fc4a850e2178d71aa5efe576dcd331db596
 F src/test1.c e8652055d04d241d4fb437b5c33ff07d9f13b4b4
@@ -180,7 +180,7 @@ F www/speed.tcl 2f6b1155b99d39adb185f900456d1d592c4832b3
 F www/sqlite.tcl 3c83b08cf9f18aa2d69453ff441a36c40e431604
 F www/tclsqlite.tcl b9271d44dcf147a93c98f8ecf28c927307abd6da
 F www/vdbe.tcl 9b9095d4495f37697fd1935d10e14c6015e80aa1
-P 5e85025be7aa4a03b0cfb4d0f28a2e44653b9d3f
-R aaef1a0aff5b12b7d4f36cc6a72499f1
+P 42c79edc2e8d1051b3bca915b4b205c601b8077f
+R 36f16e7773dddd52ae0de77fcf909446
 U drh
-Z ebbe741602d66e22ec8fa796a8084911
+Z 7d1bc38e295a20482fad97622944af0e
diff --git a/manifest.uuid b/manifest.uuid
index 42f947c657..0ec3fbc59a 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-42c79edc2e8d1051b3bca915b4b205c601b8077f
\ No newline at end of file
+d292ba5148059dce3893b80eabdca4af9f75194e
\ No newline at end of file
diff --git a/src/expr.c b/src/expr.c
index 4db369d833..513cc6f3eb 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -12,7 +12,7 @@
 ** This file contains routines used for analyzing expressions and
 ** for generating VDBE code that evaluates expressions in SQLite.
 **
-** $Id: expr.c,v 1.104 2004/01/14 03:12:42 drh Exp $
+** $Id: expr.c,v 1.105 2004/01/16 15:55:38 drh Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -26,8 +26,7 @@ Expr *sqliteExpr(int op, Expr *pLeft, Expr *pRight, Token *pToken){
   Expr *pNew;
   pNew = sqliteMalloc( sizeof(Expr) );
   if( pNew==0 ){
-    sqliteExprDelete(pLeft);
-    sqliteExprDelete(pRight);
+    /* When malloc fails, we leak memory from pLeft and pRight */
     return 0;
   }
   pNew->op = op;
@@ -38,9 +37,9 @@ Expr *sqliteExpr(int op, Expr *pLeft, Expr *pRight, Token *pToken){
     pNew->token = *pToken;
     pNew->span = *pToken;
   }else{
-    pNew->token.dyn = 0;
-    pNew->token.z = 0;
-    pNew->token.n = 0;
+    assert( pNew->token.dyn==0 );
+    assert( pNew->token.z==0 );
+    assert( pNew->token.n==0 );
     if( pLeft && pRight ){
       sqliteExprSpan(pNew, &pLeft->span, &pRight->span);
     }else{
@@ -55,14 +54,15 @@ Expr *sqliteExpr(int op, Expr *pLeft, Expr *pRight, Token *pToken){
 ** text between the two given tokens.
 */
 void sqliteExprSpan(Expr *pExpr, Token *pLeft, Token *pRight){
-  if( pExpr && pRight && pRight->z && pLeft && pLeft->z ){
+  assert( pRight!=0 );
+  assert( pLeft!=0 );
+  /* Note: pExpr might be NULL due to a prior malloc failure */
+  if( pExpr && pRight->z && pLeft->z ){
     if( pLeft->dyn==0 && pRight->dyn==0 ){
       pExpr->span.z = pLeft->z;
       pExpr->span.n = pRight->n + Addr(pRight->z) - Addr(pLeft->z);
     }else{
       pExpr->span.z = 0;
-      pExpr->span.n = 0;
-      pExpr->span.dyn = 0;
     }
   }
 }
@@ -75,18 +75,16 @@ Expr *sqliteExprFunction(ExprList *pList, Token *pToken){
   Expr *pNew;
   pNew = sqliteMalloc( sizeof(Expr) );
   if( pNew==0 ){
-    sqliteExprListDelete(pList);
+    /* sqliteExprListDelete(pList); // Leak pList when malloc fails */
     return 0;
   }
   pNew->op = TK_FUNCTION;
   pNew->pList = pList;
-  pNew->token.dyn = 0;
   if( pToken ){
     assert( pToken->dyn==0 );
     pNew->token = *pToken;
   }else{
     pNew->token.z = 0;
-    pNew->token.n = 0;
   }
   pNew->span = pNew->token;
   return pNew;
@@ -97,12 +95,12 @@ Expr *sqliteExprFunction(ExprList *pList, Token *pToken){
 */
 void sqliteExprDelete(Expr *p){
   if( p==0 ) return;
-  if( p->span.dyn && p->span.z ) sqliteFree((char*)p->span.z);
-  if( p->token.dyn && p->token.z ) sqliteFree((char*)p->token.z);
-  if( p->pLeft ) sqliteExprDelete(p->pLeft);
-  if( p->pRight ) sqliteExprDelete(p->pRight);
-  if( p->pList ) sqliteExprListDelete(p->pList);
-  if( p->pSelect ) sqliteSelectDelete(p->pSelect);
+  if( p->span.dyn ) sqliteFree((char*)p->span.z);
+  if( p->token.dyn ) sqliteFree((char*)p->token.z);
+  sqliteExprDelete(p->pLeft);
+  sqliteExprDelete(p->pRight);
+  sqliteExprListDelete(p->pList);
+  sqliteSelectDelete(p->pSelect);
   sqliteFree(p);
 }
 
@@ -129,13 +127,9 @@ Expr *sqliteExprDup(Expr *p){
     pNew->token.z = sqliteStrDup(p->token.z);
     pNew->token.dyn = 1;
   }else{
-    pNew->token.z = 0;
-    pNew->token.n = 0;
-    pNew->token.dyn = 0;
+    assert( pNew->token.z==0 );
   }
   pNew->span.z = 0;
-  pNew->span.n = 0;
-  pNew->span.dyn = 0;
   pNew->pLeft = sqliteExprDup(p->pLeft);
   pNew->pRight = sqliteExprDup(p->pRight);
   pNew->pList = sqliteExprListDup(p->pList);
@@ -149,9 +143,7 @@ void sqliteTokenCopy(Token *pTo, Token *pFrom){
     pTo->z = sqliteStrNDup(pFrom->z, pFrom->n);
     pTo->dyn = 1;
   }else{
-    pTo->n = 0;
     pTo->z = 0;
-    pTo->dyn = 0;
   }
 }
 ExprList *sqliteExprListDup(ExprList *p){
@@ -187,19 +179,21 @@ SrcList *sqliteSrcListDup(SrcList *p){
   int nByte;
   if( p==0 ) return 0;
   nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
-  pNew = sqliteMalloc( nByte );
+  pNew = sqliteMallocRaw( nByte );
   if( pNew==0 ) return 0;
   pNew->nSrc = pNew->nAlloc = p->nSrc;
   for(i=0; i<p->nSrc; i++){
-    pNew->a[i].zDatabase = sqliteStrDup(p->a[i].zDatabase);
-    pNew->a[i].zName = sqliteStrDup(p->a[i].zName);
-    pNew->a[i].zAlias = sqliteStrDup(p->a[i].zAlias);
-    pNew->a[i].jointype = p->a[i].jointype;
-    pNew->a[i].iCursor = p->a[i].iCursor;
-    pNew->a[i].pTab = 0;
-    pNew->a[i].pSelect = sqliteSelectDup(p->a[i].pSelect);
-    pNew->a[i].pOn = sqliteExprDup(p->a[i].pOn);
-    pNew->a[i].pUsing = sqliteIdListDup(p->a[i].pUsing);
+    struct SrcList_item *pNewItem = &pNew->a[i];
+    struct SrcList_item *pOldItem = &p->a[i];
+    pNewItem->zDatabase = sqliteStrDup(pOldItem->zDatabase);
+    pNewItem->zName = sqliteStrDup(pOldItem->zName);
+    pNewItem->zAlias = sqliteStrDup(pOldItem->zAlias);
+    pNewItem->jointype = pOldItem->jointype;
+    pNewItem->iCursor = pOldItem->iCursor;
+    pNewItem->pTab = 0;
+    pNewItem->pSelect = sqliteSelectDup(pOldItem->pSelect);
+    pNewItem->pOn = sqliteExprDup(pOldItem->pOn);
+    pNewItem->pUsing = sqliteIdListDup(pOldItem->pUsing);
   }
   return pNew;
 }
@@ -207,21 +201,23 @@ IdList *sqliteIdListDup(IdList *p){
   IdList *pNew;
   int i;
   if( p==0 ) return 0;
-  pNew = sqliteMalloc( sizeof(*pNew) );
+  pNew = sqliteMallocRaw( sizeof(*pNew) );
   if( pNew==0 ) return 0;
   pNew->nId = pNew->nAlloc = p->nId;
-  pNew->a = sqliteMalloc( p->nId*sizeof(p->a[0]) );
+  pNew->a = sqliteMallocRaw( p->nId*sizeof(p->a[0]) );
   if( pNew->a==0 ) return 0;
   for(i=0; i<p->nId; i++){
-    pNew->a[i].zName = sqliteStrDup(p->a[i].zName);
-    pNew->a[i].idx = p->a[i].idx;
+    struct IdList_item *pNewItem = &pNew->a[i];
+    struct IdList_item *pOldItem = &p->a[i];
+    pNewItem->zName = sqliteStrDup(pOldItem->zName);
+    pNewItem->idx = pOldItem->idx;
   }
   return pNew;
 }
 Select *sqliteSelectDup(Select *p){
   Select *pNew;
   if( p==0 ) return 0;
-  pNew = sqliteMalloc( sizeof(*p) );
+  pNew = sqliteMallocRaw( sizeof(*p) );
   if( pNew==0 ) return 0;
   pNew->isDistinct = p->isDistinct;
   pNew->pEList = sqliteExprListDup(p->pEList);
@@ -250,28 +246,28 @@ ExprList *sqliteExprListAppend(ExprList *pList, Expr *pExpr, Token *pName){
   if( pList==0 ){
     pList = sqliteMalloc( sizeof(ExprList) );
     if( pList==0 ){
-      sqliteExprDelete(pExpr);
+      /* sqliteExprDelete(pExpr); // Leak memory if malloc fails */
       return 0;
     }
-    pList->nAlloc = 0;
+    assert( pList->nAlloc==0 );
   }
   if( pList->nAlloc<=pList->nExpr ){
-    struct ExprList_item *a;
     pList->nAlloc = pList->nAlloc*2 + 4;
-    a = sqliteRealloc(pList->a, pList->nAlloc*sizeof(pList->a[0]));
-    if( a==0 ){
-      sqliteExprDelete(pExpr);
+    pList->a = sqliteRealloc(pList->a, pList->nAlloc*sizeof(pList->a[0]));
+    if( pList->a==0 ){
+      /* sqliteExprDelete(pExpr); // Leak memory if malloc fails */
+      pList->nExpr = pList->nAlloc = 0;
       return pList;
     }
-    pList->a = a;
   }
-  if( pList->a && (pExpr || pName) ){
-    i = pList->nExpr++;
-    memset(&pList->a[i], 0, sizeof(pList->a[i]));
-    pList->a[i].pExpr = pExpr;
+  assert( pList->a!=0 );
+  if( pExpr || pName ){
+    struct ExprList_item *pItem = &pList->a[pList->nExpr++];
+    memset(pItem, 0, sizeof(*pItem));
+    pItem->pExpr = pExpr;
     if( pName ){
-      sqliteSetNString(&pList->a[i].zName, pName->z, pName->n, 0);
-      sqliteDequote(pList->a[i].zName);
+      sqliteSetNString(&pItem->zName, pName->z, pName->n, 0);
+      sqliteDequote(pItem->zName);
     }
   }
   return pList;
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 9894786077..381b538e6e 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -11,7 +11,7 @@
 *************************************************************************
 ** Internal interface definitions for SQLite.
 **
-** @(#) $Id: sqliteInt.h,v 1.208 2004/01/15 02:44:03 drh Exp $
+** @(#) $Id: sqliteInt.h,v 1.209 2004/01/16 15:55:38 drh Exp $
 */
 #include "config.h"
 #include "sqlite.h"
@@ -587,6 +587,10 @@ struct Index {
 /*
 ** Each token coming out of the lexer is an instance of
 ** this structure.  Tokens are also used as part of an expression.
+**
+** Note if Token.z==0 then Token.dyn and Token.n are undefined and
+** may contain random values.  Do not make any assuptions about Token.dyn
+** and Token.n when Token.z==0.
 */
 struct Token {
   const char *z;      /* Text of the token.  Not NULL-terminated! */