eden-emu/opus
15
0
Fork 0
mirror of https://github.com/xiph/opus.git synced 2025-06-03 17:17:42 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Hack that makes the SMALL_FOOTPRINT CELT decoder use only 4.25 kB of stack.

Browse source
This commit is contained in:
Jean-Marc Valin 2014-01-06 09:11:52 -05:00
parent bdc7b93358
commit 32454dcadc
1 changed files with 16 additions and 8 deletions
Download patch file Download diff file Expand all files Collapse all files

24
celt/celt_decoder.c
View file

@ -708,7 +708,11 @@ int celt_decode_with_ec(CELTDecoder * OPUS_RESTRICT st, const unsigned char *dat
opus_int32 bits; opus_int32 bits;
ec_dec _dec; ec_dec _dec;
VARDECL(celt_sig, freq); VARDECL(celt_sig, freq);
#ifdef SMALL_FOOTPRINT
celt_norm *X;
#else
VARDECL(celt_norm, X); VARDECL(celt_norm, X);
#endif
VARDECL(int, fine_quant); VARDECL(int, fine_quant);
VARDECL(int, pulses); VARDECL(int, pulses);
VARDECL(int, cap); VARDECL(int, cap);
@ -944,9 +948,21 @@ int celt_decode_with_ec(CELTDecoder * OPUS_RESTRICT st, const unsigned char *dat
unquant_fine_energy(mode, start, end, oldBandE, fine_quant, dec, C); unquant_fine_energy(mode, start, end, oldBandE, fine_quant, dec, C);
c=0; do {
OPUS_MOVE(decode_mem[c], decode_mem[c]+N, DECODE_BUFFER_SIZE-N+overlap/2);
out_syn[c] = decode_mem[c]+DECODE_BUFFER_SIZE-N;
} while (++c<CC);
/* Decode fixed codebook */ /* Decode fixed codebook */
ALLOC(collapse_masks, C*nbEBands, unsigned char); ALLOC(collapse_masks, C*nbEBands, unsigned char);
#ifdef SMALL_FOOTPRINT
/* This is an ugly hack that breaks aliasing rules and would be easily broken,
but it saves almost 4kB of stack. */
X = (celt_norm*)(out_syn[CC-1]+overlap/2);
#else
ALLOC(X, C*N, celt_norm); /**< Interleaved normalised MDCTs */ ALLOC(X, C*N, celt_norm); /**< Interleaved normalised MDCTs */
#endif
quant_all_bands(0, mode, start, end, X, C==2 ? X+N : NULL, collapse_masks, quant_all_bands(0, mode, start, end, X, C==2 ? X+N : NULL, collapse_masks,
NULL, pulses, shortBlocks, spread_decision, dual_stereo, intensity, tf_res, NULL, pulses, shortBlocks, spread_decision, dual_stereo, intensity, tf_res,
@ -970,14 +986,6 @@ int celt_decode_with_ec(CELTDecoder * OPUS_RESTRICT st, const unsigned char *dat
oldBandE[i] = -QCONST16(28.f,DB_SHIFT); oldBandE[i] = -QCONST16(28.f,DB_SHIFT);
} }
c=0; do {
OPUS_MOVE(decode_mem[c], decode_mem[c]+N, DECODE_BUFFER_SIZE-N+overlap/2);
} while (++c<CC);
c=0; do {
out_syn[c] = decode_mem[c]+DECODE_BUFFER_SIZE-N;
} while (++c<CC);
celt_synthesis(mode, X, out_syn, oldBandE, start, effEnd, C, CC, isTransient, LM, st->downsample, silence); celt_synthesis(mode, X, out_syn, oldBandE, start, effEnd, C, CC, isTransient, LM, st->downsample, silence);
c=0; do { c=0; do {