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DSPHLE: Preserve fractional sample position between voice render calls. sounds slightly, slightly cleaner :P

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git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@3637 8ced0084-cf51-0410-be5f-012b33b47a6e
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hrydgard
2009-07-01 22:26:01 +00:00
parent f6af7794cd
commit 0008d5ef77
4 changed files with 52 additions and 31 deletions
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31
docs/DSP/DSP_UC_Zelda.txt
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@ -2880,15 +2880,23 @@ void 087c_DefaultDecoder()
087c 8100 clr $ACC0 // ACC0 = 0
087d 1f5e mrr $AX0.H, $AC0.M
087e 00d8 0402 lr $AX0.L, @0x0402 // AX0.L = PB.RatioInt
0880 00dc 0430 lr $AC0.L, @0x0430 // AC0.L = PB.RatioFrac
// Sample fraction is stored in a common way, but sample position is not, so
// it's in the individual decoders. Some decoders, like square wave, only care about
// fractional sample position. So here we just load up the fractional sample
// position before handing control over.
0880 00dc 0430 lr $AC0.L, @0x0430 // AC0.L = PB.CurSampleFrac
0882 0080 0520 lri $AR0, #0x0520 // AR0 = 0x0520
0884 00df 0480 lr $AC1.M, @0x0480
0886 1501 lsl $ACC1, #1 // AC1.M = (PB.Format << 1)
0887 0340 007e andi $AC1.M, #0x007e // AC1.M &= 0x007e
0889 0300 0891 addi $AC1.M, #0x0891 // AC1.M += 0x0891
088b 1c5f mrr $AR2, $AC1.M // AR2 = AC1.M
088c 175f callr $AR2 // (*$AR2)() <-- See jump table at 0x0891
088d 00fc 0430 sr @0x0430, $AC0.L // PB.RatioFrac = AC0.L
// 0884 00df 0480 lr $AC1.M, @0x0480
// 0886 1501 lsl $ACC1, #1 // AC1.M = (PB.Format << 1)
// 0887 0340 007e andi $AC1.M, #0x007e // AC1.M &= 0x007e
// 0889 0300 0891 addi $AC1.M, #0x0891 // AC1.M += 0x0891
// 088b 1c5f mrr $AR2, $AC1.M // AR2 = AC1.M
// 088c 175f callr $AR2 // (*$AR2)() <-- See jump table at 0x0891
JumpTable0891(PB.Format);
088d 00fc 0430 sr @0x0430, $AC0.L // PB.CurSampleFrac = AC0.L
// 088f 029f 02d8 jmp 0x02d8
GOTO ContinueWithBlock: // in SyncFrame
@ -2916,7 +2924,7 @@ void 087c_DefaultDecoder()
08b1 02df ret
void 08b2_Decoder0x0_SquareWave() {
08b2 1401 lsl $ACC0, #1 // t = PB.RatioFrac * 2
08b2 1401 lsl $ACC0, #1 // t = samplePosition * 2
// Set up sound buffers
//08b3 009b c000 lri $AX1.H, #0xc000
@ -2934,16 +2942,15 @@ void 08b2_Decoder0x0_SquareWave() {
else
*$AR0++ = 0xc000;
08bf 4800 addax $ACC0, $AX0.L // t += PB.RatioInt
08bf 4800 addax $ACC0, $AX0.L // t += PB.Ratio
}
08c0 147f lsr $ACC0, #-1 // t /= 2
// Where ACC0 gets stored after this is interesting.
// 08c1 02df ret
}
void 08c2_Decoder0x3_RectangleWave() {
08c2 1402 lsl $ACC0, #2 // t = PB.RatioFrac * 4
08c2 1402 lsl $ACC0, #2 // t = PB.CurSampleFrac * 4
08c3 8900 clr $ACC1 // ACC1 = 0
08c4 1fb8 mrr $AC1.L, $AX0.L // AC1.L = PB.RatioInt
08c5 1501 lsl $ACC1, #1 // ACC1 *= 2