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dmix: add S24_3LE support

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Add to the dmix plugin support for the S24_3LE sample format which is
used by 24-bit USB devices.

The optimized assembler version uses only 23 bits for sample data so
that the lowest bit can be used for synchronization because there is no
24-bit cmpxchg instruction.
This commit is contained in:
Clemens Ladisch 2005-12-19 07:39:03 +00:00
parent 46f81f994b
commit 45f63a8735
8 changed files with 404 additions and 7 deletions
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205
src/pcm/pcm_dmix_i386.h
View file

@ -352,3 +352,208 @@ static void MIX_AREAS2(unsigned int size,
: "esi", "edi", "edx", "ecx", "eax"
);
}
/*
* 24-bit version for plain i386
*/
static void MIX_AREAS3(unsigned int size,
volatile unsigned char *dst, unsigned char *src,
volatile signed int *sum, size_t dst_step,
size_t src_step, size_t sum_step)
{
unsigned int old_ebx;
/*
* ESI - src
* EDI - dst
* EBX - sum
* ECX - old sample
* EAX - sample / temporary
* EDX - temporary
*/
__asm__ __volatile__ (
"\n"
"\tmovl %%ebx, %7\n" /* ebx is GOT pointer (-fPIC) */
/*
* initialization, load ESI, EDI, EBX registers
*/
"\tmovl %1, %%edi\n"
"\tmovl %2, %%esi\n"
"\tmovl %3, %%ebx\n"
"\tcmpl $0, %0\n"
"\tjnz 1f\n"
"\tjmp 6f\n"
"\t.p2align 4,,15\n"
"1:"
/*
* sample = *src;
* sum_sample = *sum;
* if (test_and_set_bit(0, dst) == 0)
* sample -= sum_sample;
* *sum += sample;
*/
"\tmovsbl 2(%%esi), %%eax\n"
"\tmovzwl (%%esi), %%ecx\n"
"\tmovl (%%ebx), %%edx\n"
"\tsall $16, %%eax\n"
"\t" LOCK_PREFIX "btsl $0, (%%edi)\n"
"\tleal (%%ecx,%%eax,1), %%ecx\n"
"\tjc 2f\n"
"\tsubl %%edx, %%ecx\n"
"2:"
"\t" LOCK_PREFIX "addl %%ecx, (%%ebx)\n"
/*
* do {
* sample = old_sample = *sum;
* saturate(sample);
* *dst = sample | 1;
* } while (old_sample != *sum);
*/
"3:"
"\tmovl (%%ebx), %%ecx\n"
/*
* if (sample > 0x7fffff)
*/
"\tmovl $0x7fffff, %%eax\n"
"\tcmpl %%eax, %%ecx\n"
"\tjg 4f\n"
/*
* if (sample < -0x7fffff)
*/
"\tmovl $-0x7fffff, %%eax\n"
"\tcmpl %%eax, %%ecx\n"
"\tjl 4f\n"
"\tmovl %%ecx, %%eax\n"
"\torl $1, %%eax\n"
"4:"
"\tmovw %%ax, (%%edi)\n"
"\tshrl $16, %%eax\n"
"\tmovb %%al, 2(%%edi)\n"
"\tcmpl %%ecx, (%%ebx)\n"
"\tjnz 3b\n"
/*
* while (size-- > 0)
*/
"\tdecl %0\n"
"\tjz 6f\n"
"\tadd %4, %%edi\n"
"\tadd %5, %%esi\n"
"\tadd %6, %%ebx\n"
"\tjmp 1b\n"
"6:"
"\tmovl %7, %%ebx\n" /* ebx is GOT pointer (-fPIC) */
: /* no output regs */
: "m" (size), "m" (dst), "m" (src),
"m" (sum), "m" (dst_step), "m" (src_step),
"m" (sum_step), "m" (old_ebx)
: "esi", "edi", "edx", "ecx", "eax"
);
}
/*
* 24-bit version for Pentium Pro/II
*/
static void MIX_AREAS3_CMOV(unsigned int size,
volatile unsigned char *dst, unsigned char *src,
volatile signed int *sum, size_t dst_step,
size_t src_step, size_t sum_step)
{
unsigned int old_ebx;
/*
* ESI - src
* EDI - dst
* EBX - sum
* ECX - old sample
* EAX - sample / temporary
* EDX - temporary
*/
__asm__ __volatile__ (
"\n"
"\tmovl %%ebx, %7\n" /* ebx is GOT pointer (-fPIC) */
/*
* initialization, load ESI, EDI, EBX registers
*/
"\tmovl %1, %%edi\n"
"\tmovl %2, %%esi\n"
"\tmovl %3, %%ebx\n"
"\tcmpl $0, %0\n"
"\tjz 6f\n"
"\t.p2align 4,,15\n"
"1:"
/*
* sample = *src;
* sum_sample = *sum;
* if (test_and_set_bit(0, dst) == 0)
* sample -= sum_sample;
* *sum += sample;
*/
"\tmovsbl 2(%%esi), %%eax\n"
"\tmovzwl (%%esi), %%ecx\n"
"\tmovl (%%ebx), %%edx\n"
"\tsall $16, %%eax\n"
"\t" LOCK_PREFIX "btsl $0, (%%edi)\n"
"\tleal (%%ecx,%%eax,1), %%ecx\n"
"\tjc 2f\n"
"\tsubl %%edx, %%ecx\n"
"2:"
"\t" LOCK_PREFIX "addl %%ecx, (%%ebx)\n"
/*
* do {
* sample = old_sample = *sum;
* saturate(sample);
* *dst = sample | 1;
* } while (old_sample != *sum);
*/
"3:"
"\tmovl (%%ebx), %%ecx\n"
"\tmovl $0x7fffff, %%eax\n"
"\tmovl $-0x7fffff, %%edx\n"
"\tcmpl %%eax, %%ecx\n"
"\tcmovng %%ecx, %%eax\n"
"\tcmpl %%edx, %%ecx\n"
"\tcmovl %%edx, %%eax\n"
"\torl $1, %%eax\n"
"\tmovw %%ax, (%%edi)\n"
"\tshrl $16, %%eax\n"
"\tmovb %%al, 2(%%edi)\n"
"\tcmpl %%ecx, (%%ebx)\n"
"\tjnz 3b\n"
/*
* while (size-- > 0)
*/
"\tadd %4, %%edi\n"
"\tadd %5, %%esi\n"
"\tadd %6, %%ebx\n"
"\tdecl %0\n"
"\tjnz 1b\n"
"6:"
"\tmovl %7, %%ebx\n" /* ebx is GOT pointer (-fPIC) */
: /* no output regs */
: "m" (size), "m" (dst), "m" (src),
"m" (sum), "m" (dst_step), "m" (src_step),
"m" (sum_step), "m" (old_ebx)
: "esi", "edi", "edx", "ecx", "eax"
);
}