add support for 64bit datapath through inverse filter

src/libFLAC/stream_decoder.c

@@ -78,6 +78,7 @@ typedef struct FLAC__StreamDecoderPrivate {
 	FLAC__StreamDecoderMetadataCallback metadata_callback;
 	FLAC__StreamDecoderErrorCallback error_callback;
 	void (*local_lpc_restore_signal)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
+	void (*local_lpc_restore_signal_64bit)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
 	void (*local_lpc_restore_signal_16bit)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
 	void *client_data;
 	FLAC__BitBuffer *input;
@@ -260,6 +261,7 @@ FLAC__StreamDecoderState FLAC__stream_decoder_init(FLAC__StreamDecoder *decoder)
 	FLAC__cpu_info(&decoder->private_->cpuinfo);
 	/* first default to the non-asm routines */
 	decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal;
+	decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide;
 	decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal;
 	/* now override with asm where appropriate */
 #ifndef FLAC__NO_ASM
@@ -1741,8 +1743,10 @@ FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, unsigned channel, un
 	memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
 	if(bps <= 16 && subframe->qlp_coeff_precision <= 16)
 		decoder->private_->local_lpc_restore_signal_16bit(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel]+order);
-	else
+	else if(bps + subframe->qlp_coeff_precision + order <= 32)
 		decoder->private_->local_lpc_restore_signal(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel]+order);
+	else
+		decoder->private_->local_lpc_restore_signal_64bit(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel]+order);
 
 	return true;
 }