Fix a code generator bug caused by the new CSE optimization. Add test cases
to prevent a recurrence. (CVS 5011)
FossilOrigin-Name: d04246a46399e839e70b1bd57e209f80143f0d5b
diff --git a/src/expr.c b/src/expr.c
index 3002ef7..f58743b 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 1.366 2008/04/11 15:36:03 drh Exp $
+** $Id: expr.c,v 1.367 2008/04/15 12:14:22 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
@@ -2104,6 +2104,24 @@
}
/*
+** If the last instruction coded is an ephemeral copy of any of
+** the registers in the nReg registers beginning with iReg, then
+** convert the last instruction from OP_SCopy to OP_Copy.
+*/
+void sqlite3ExprHardCopy(Parse *pParse, int iReg, int nReg){
+ int addr;
+ VdbeOp *pOp;
+ Vdbe *v;
+
+ v = pParse->pVdbe;
+ addr = sqlite3VdbeCurrentAddr(v);
+ pOp = sqlite3VdbeGetOp(v, addr-1);
+ if( pOp->opcode==OP_SCopy && pOp->p1>=iReg && pOp->p1<iReg+nReg ){
+ pOp->opcode = OP_Copy;
+ }
+}
+
+/*
** Generate code into the current Vdbe to evaluate the given
** expression. Attempt to store the results in register "target".
** Return the register where results are stored.
@@ -2374,7 +2392,7 @@
if( pList ){
nExpr = pList->nExpr;
r1 = sqlite3GetTempRange(pParse, nExpr);
- sqlite3ExprCodeExprList(pParse, pList, r1);
+ sqlite3ExprCodeExprList(pParse, pList, r1, 1);
}else{
nExpr = r1 = 0;
}
@@ -2804,7 +2822,8 @@
int sqlite3ExprCodeExprList(
Parse *pParse, /* Parsing context */
ExprList *pList, /* The expression list to be coded */
- int target /* Where to write results */
+ int target, /* Where to write results */
+ int doHardCopy /* Call sqlite3ExprHardCopy on each element if true */
){
struct ExprList_item *pItem;
int i, n;
@@ -2814,9 +2833,9 @@
}
assert( target>0 );
n = pList->nExpr;
- for(pItem=pList->a, i=n; i>0; i--, pItem++){
- sqlite3ExprCode(pParse, pItem->pExpr, target);
- target++;
+ for(pItem=pList->a, i=0; i<n; i++, pItem++){
+ sqlite3ExprCode(pParse, pItem->pExpr, target+i);
+ if( doHardCopy ) sqlite3ExprHardCopy(pParse, target, n);
}
return n;
}