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Further reductions in the amount of stack space required. (CVS 6707)

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FossilOrigin-Name: 04bad9eb6dd8bf7cafc9f3918b676e95d5b1c984
This commit is contained in:
drh
2009-06-02 21:31:38 +00:00
parent c54a617e1f
commit e98c9049a0
7 changed files with 91 additions and 66 deletions
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41
src/bitvec.c
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@@ -34,7 +34,7 @@
** start of a transaction, and is thus usually less than a few thousand,
** but can be as large as 2 billion for a really big database.
**
** @(#) $Id: bitvec.c,v 1.14 2009/04/01 23:49:04 drh Exp $
** @(#) $Id: bitvec.c,v 1.15 2009/06/02 21:31:39 drh Exp $
*/
#include "sqliteInt.h"
@@ -209,15 +209,20 @@ bitvec_set_rehash:
if( p->nSet>=BITVEC_MXHASH ){
unsigned int j;
int rc;
u32 aiValues[BITVEC_NINT];
memcpy(aiValues, p->u.aHash, sizeof(aiValues));
memset(p->u.apSub, 0, sizeof(aiValues));
p->iDivisor = (p->iSize + BITVEC_NPTR - 1)/BITVEC_NPTR;
rc = sqlite3BitvecSet(p, i);
for(j=0; j<BITVEC_NINT; j++){
if( aiValues[j] ) rc |= sqlite3BitvecSet(p, aiValues[j]);
u32 *aiValues = sqlite3StackAllocRaw(0, sizeof(p->u.aHash));
if( aiValues==0 ){
return SQLITE_NOMEM;
}else{
memcpy(aiValues, p->u.aHash, sizeof(p->u.aHash));
memset(p->u.apSub, 0, sizeof(p->u.apSub));
p->iDivisor = (p->iSize + BITVEC_NPTR - 1)/BITVEC_NPTR;
rc = sqlite3BitvecSet(p, i);
for(j=0; j<BITVEC_NINT; j++){
if( aiValues[j] ) rc |= sqlite3BitvecSet(p, aiValues[j]);
}
sqlite3StackFree(0, aiValues);
return rc;
}
return rc;
}
bitvec_set_end:
p->nSet++;
@@ -227,8 +232,11 @@ bitvec_set_end:
/*
** Clear the i-th bit.
**
** pBuf must be a pointer to at least BITVEC_SZ bytes of temporary storage
** that BitvecClear can use to rebuilt its hash table.
*/
void sqlite3BitvecClear(Bitvec *p, u32 i){
void sqlite3BitvecClear(Bitvec *p, u32 i, void *pBuf){
assert( p!=0 );
assert( i>0 );
i--;
@@ -244,9 +252,9 @@ void sqlite3BitvecClear(Bitvec *p, u32 i){
p->u.aBitmap[i/BITVEC_SZELEM] &= ~(1 << (i&(BITVEC_SZELEM-1)));
}else{
unsigned int j;
u32 aiValues[BITVEC_NINT];
memcpy(aiValues, p->u.aHash, sizeof(aiValues));
memset(p->u.aHash, 0, sizeof(aiValues));
u32 *aiValues = pBuf;
memcpy(aiValues, p->u.aHash, sizeof(p->u.aHash));
memset(p->u.aHash, 0, sizeof(p->u.aHash));
p->nSet = 0;
for(j=0; j<BITVEC_NINT; j++){
if( aiValues[j] && aiValues[j]!=(i+1) ){
@@ -330,12 +338,14 @@ int sqlite3BitvecBuiltinTest(int sz, int *aOp){
unsigned char *pV = 0;
int rc = -1;
int i, nx, pc, op;
void *pTmpSpace;
/* Allocate the Bitvec to be tested and a linear array of
** bits to act as the reference */
pBitvec = sqlite3BitvecCreate( sz );
pV = sqlite3_malloc( (sz+7)/8 + 1 );
if( pBitvec==0 || pV==0 ) goto bitvec_end;
pTmpSpace = sqlite3_malloc(BITVEC_SZ);
if( pBitvec==0 || pV==0 || pTmpSpace==0 ) goto bitvec_end;
memset(pV, 0, (sz+7)/8 + 1);
/* Run the program */
@@ -368,7 +378,7 @@ int sqlite3BitvecBuiltinTest(int sz, int *aOp){
}
}else{
CLEARBIT(pV, (i+1));
sqlite3BitvecClear(pBitvec, i+1);
sqlite3BitvecClear(pBitvec, i+1, pTmpSpace);
}
}
@@ -389,6 +399,7 @@ int sqlite3BitvecBuiltinTest(int sz, int *aOp){
/* Free allocated structure */
bitvec_end:
sqlite3_free(pTmpSpace);
sqlite3_free(pV);
sqlite3BitvecDestroy(pBitvec);
return rc;