Kimmo Mustonen wrote:
>
> On Sat, 27 May 2000, Mark Taylor wrote:
>
> > The problem is gfc->cw_lower_index. It is set to 6, and is never
> > changed. Yet it has been changed to -1001465578, so there is
> > I would start by putting print statements in lame_encode_frame(),
> > and see if you can narrow down in which major block
> > of code cw_lower_limit is overwritten (psycho acoustics, MDCTs,
> > outer_loop or format_bitstream?
>
> The value is changed during L3psycho_anal in psymodel.c. I put lots of
> assertions in the channel loop (a very long loop really!) and the value
> was changed before the end of the loop:
>
> ---8<---
> assert(gfc->cw_lower_index == 6); /***** line 865 *****/
>
> /* threshold calculation for short blocks */
> for (sblock = 0; sblock < 3; sblock++) {
> j = 0;
> for (b = 0; b < gfc->npart_s_orig; b++) {
> int i;
> FLOAT ecb;
> ecb = gfc->energy_s[sblock][j++];
> for (i = gfc->numlines_s[b]; i > 0; i--) {
> ecb += gfc->energy_s[sblock][j++];
> }
> eb[b] = ecb;
> }
>
> for (b = 0; b < gfc->npart_s; b++) {
> FLOAT8 ecb;
> ecb = 0;
> for (k = gfc->s3ind_s[b][0]; k <= gfc->s3ind_s[b][1]; k++) {
> ecb += gfc->s3_s[b][k] * eb[k];
> }
> thr[b] = Max(1e-6, ecb);
> }
>
> for (sb = 0; sb < SBPSY_s; sb++) {
> FLOAT8 enn, thmm;
> enn = gfc->w1_s[sb] * eb[gfc->bu_s[sb]] + gfc->w2_s[sb] *
> eb[gfc->bo_s[sb]];
> thmm = gfc->w1_s[sb] *thr[gfc->bu_s[sb]] + gfc->w2_s[sb] *
> thr[gfc->bo_s[sb]];
> for (b = gfc->bu_s[sb]+1; b < gfc->bo_s[sb]; b++) {
> enn += eb[b];
> thmm += thr[b];
> }
> /*
> printf("&gfc->cw_lower_index = 0x%08x\n", &gfc->cw_lower_index);
> printf("&gfc->en[chn].s[sb][sblock] = 0x%08x\n",
> &gfc->en[chn].s[sb][sblock]);
> printf("&gfc->thm[chn].s[sb][sblock] = 0x%08x\n",
> &gfc->thm[chn].s[sb][sblock]);
> */
> gfc->en[chn].s[sb][sblock] = enn;
> gfc->thm[chn].s[sb][sblock] = thmm;
> }
> #if 0 /***** line 905 *****/
> assert(gfc->cw_lower_index == 6);
> #endif
> }
> assert(gfc->cw_lower_index == 6); /***** line 909 *****/
> } /* end loop over chn */
>
> assert(gfc->cw_lower_index == 6);
> ---8<---
>
> The result:
>
> Assertion (gfc->cw_lower_index == 6) failed in file psymodel.c at line 909
>
> On line 865 the assert condition is still true.
>
> Note that the line numbers in my version are very different from the
> original version, because I have lots of assertions added before these
> ones.
>
> But if I change the #if on line 905 to #if 1, the problem disappears and
> lame seems to work ok.
if ( You are saying : "Adding this assert() fixes the problem" )
then {
This means that you are triggering some compiler bug.
At least it looks like that to me.
Rationale : The added code doesn't really do anything, yet
the behaviour is different.
}
> So it's quite difficult to track it down more
> precisely. But I expect that it could be those gfc->en or gfc->thm that
> could be accessed out of bounds.
David Balazic
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