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fix ym2612 asm, rework EG

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this should be split, but I'm lazy
EG saves ~900 bytes
This commit is contained in:
notaz 2017-09-30 00:19:55 +03:00
parent e0bcb7a90d
commit 6d28fb5023
3 changed files with 117 additions and 157 deletions
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108
pico/sound/ym2612.c
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@ -739,83 +739,57 @@ INLINE int advance_lfo(int lfo_ampm, UINT32 lfo_cnt_old, UINT32 lfo_cnt)
return lfo_ampm;
}
#define EG_INC_VAL() \
((1 << ((pack >> ((eg_cnt>>shift)&7)*3)&7)) >> 1)
INLINE UINT32 update_eg_phase(FM_SLOT *SLOT, UINT32 eg_cnt)
INLINE void update_eg_phase(UINT16 *vol_out, FM_SLOT *SLOT, UINT32 eg_cnt)
{
INT32 volume = SLOT->volume;
UINT32 pack = SLOT->eg_pack[SLOT->state - 1];
UINT32 shift = pack >> 24;
INT32 eg_inc_val;
switch(SLOT->state)
if (eg_cnt & ((1 << shift) - 1))
return;
eg_inc_val = pack >> ((eg_cnt >> shift) & 7) * 3;
eg_inc_val = (1 << (eg_inc_val & 7)) >> 1;
switch (SLOT->state)
{
case EG_ATT: /* attack phase */
case EG_ATT: /* attack phase */
volume += ( ~volume * eg_inc_val ) >> 4;
if ( volume <= MIN_ATT_INDEX )
{
UINT32 pack = SLOT->eg_pack_ar;
UINT32 shift = pack>>24;
if ( !(eg_cnt & ((1<<shift)-1) ) )
{
volume += ( ~volume * EG_INC_VAL() ) >>4;
if (volume <= MIN_ATT_INDEX)
{
volume = MIN_ATT_INDEX;
SLOT->state = EG_DEC;
}
}
break;
volume = MIN_ATT_INDEX;
SLOT->state = EG_DEC;
}
break;
case EG_DEC: /* decay phase */
case EG_DEC: /* decay phase */
volume += eg_inc_val;
if ( volume >= (INT32) SLOT->sl )
SLOT->state = EG_SUS;
break;
case EG_SUS: /* sustain phase */
volume += eg_inc_val;
if ( volume >= MAX_ATT_INDEX )
{
UINT32 pack = SLOT->eg_pack_d1r;
UINT32 shift = pack>>24;
if ( !(eg_cnt & ((1<<shift)-1) ) )
{
volume += EG_INC_VAL();
if ( volume >= (INT32) SLOT->sl )
SLOT->state = EG_SUS;
}
break;
volume = MAX_ATT_INDEX;
/* do not change SLOT->state (verified on real chip) */
}
break;
case EG_SUS: /* sustain phase */
case EG_REL: /* release phase */
volume += eg_inc_val;
if ( volume >= MAX_ATT_INDEX )
{
UINT32 pack = SLOT->eg_pack_d2r;
UINT32 shift = pack>>24;
if ( !(eg_cnt & ((1<<shift)-1) ) )
{
volume += EG_INC_VAL();
if ( volume >= MAX_ATT_INDEX )
{
volume = MAX_ATT_INDEX;
/* do not change SLOT->state (verified on real chip) */
}
}
break;
}
case EG_REL: /* release phase */
{
UINT32 pack = SLOT->eg_pack_rr;
UINT32 shift = pack>>24;
if ( !(eg_cnt & ((1<<shift)-1) ) )
{
volume += EG_INC_VAL();
if ( volume >= MAX_ATT_INDEX )
{
volume = MAX_ATT_INDEX;
SLOT->state = EG_OFF;
}
}
break;
volume = MAX_ATT_INDEX;
SLOT->state = EG_OFF;
}
break;
}
SLOT->volume = volume;
return SLOT->tl + ((UINT32)volume); /* tl is 7bit<<3, volume 0-1023 (0-2039 total) */
*vol_out = SLOT->tl + volume; /* tl is 7bit<<3, volume 0-1023 (0-2039 total) */
}
#endif
@ -873,10 +847,10 @@ static void chan_render_loop(chan_rend_context *ct, int *buffer, int length)
ct->eg_timer -= EG_TIMER_OVERFLOW;
ct->eg_cnt++;
if (ct->CH->SLOT[SLOT1].state != EG_OFF) ct->vol_out1 = update_eg_phase(&ct->CH->SLOT[SLOT1], ct->eg_cnt);
if (ct->CH->SLOT[SLOT2].state != EG_OFF) ct->vol_out2 = update_eg_phase(&ct->CH->SLOT[SLOT2], ct->eg_cnt);
if (ct->CH->SLOT[SLOT3].state != EG_OFF) ct->vol_out3 = update_eg_phase(&ct->CH->SLOT[SLOT3], ct->eg_cnt);
if (ct->CH->SLOT[SLOT4].state != EG_OFF) ct->vol_out4 = update_eg_phase(&ct->CH->SLOT[SLOT4], ct->eg_cnt);
if (ct->CH->SLOT[SLOT1].state != EG_OFF) update_eg_phase(&ct->vol_out1, &ct->CH->SLOT[SLOT1], ct->eg_cnt);
if (ct->CH->SLOT[SLOT2].state != EG_OFF) update_eg_phase(&ct->vol_out2, &ct->CH->SLOT[SLOT2], ct->eg_cnt);
if (ct->CH->SLOT[SLOT3].state != EG_OFF) update_eg_phase(&ct->vol_out3, &ct->CH->SLOT[SLOT3], ct->eg_cnt);
if (ct->CH->SLOT[SLOT4].state != EG_OFF) update_eg_phase(&ct->vol_out4, &ct->CH->SLOT[SLOT4], ct->eg_cnt);
}
if (ct->pack & 4) continue; /* output disabled */
@ -1071,7 +1045,7 @@ static void chan_render_loop(chan_rend_context *ct, int *buffer, int length)
} else {
buffer[scounter] += smp;
}
ct->algo = 8; // algo is only used in asm, here only bit3 is used
ct->algo |= 8;
}
/* update phase counters AFTER output calculations */