FSF addresses used in PA sources are no longer valid and rpmlint
generates numerous warnings during packaging because of this.
This patch changes all FSF addresses to FSF web page according to
the GPL how-to: https://www.gnu.org/licenses/gpl-howto.en.html
Done automatically by sed-ing through sources.
building PA with -O0 leads to test failure in mix-test on i386
issue reported by Felipe, see
http://lists.freedesktop.org/archives/pulseaudio-discuss/2014-August/021406.html
the problem is the value 0xbeffbd7f: when byte-swapped it becomes 0x7fbdffbe and according
to IEEE-754 represents a signalling NaN (starting with s111 1111 10, see http://en.wikipedia.org/wiki/NaN)
when this value is assigned to a floating point register, it becomes 0x7ffdffbe, representing
a quiet NaN (starting with s111 1111 11) -- a signalling NaN is turned into a quiet NaN!
so PA_FLOAT32_SWAP(PA_FLOAT32_SWAP(x)) != x for certain values, uhuh!
the following test code can be used; due to volatile, it will always demonstrate the issue;
without volatile, it depends on the optimization level (i386, 32-bit, gcc 4.9):
// snip
static inline float PA_FLOAT32_SWAP(float x) {
union {
float f;
uint32_t u;
} t;
t.f = x;
t.u = bswap_32(t.u);
return t.f;
}
int main() {
unsigned x = 0xbeffbd7f;
volatile float f = PA_FLOAT32_SWAP(*(float *)&x);
printf("%08x %08x %08x %f\n", 0xbeffbd7f, *(unsigned *)&f, bswap_32(*(unsigned *)&f), f);
}
// snip
the problem goes away with optimization when no temporary floating point registers are used
the proposed solution is to avoid passing swapped floating point data in a
float; this is done with new functions PA_READ_FLOAT32RE() and PA_WRITE_FLOAT32RE()
which use uint32_t to dereference a pointer and byte-swap the data, hence no temporary
float variable is used
also delete PA_FLOAT32_TO_LE()/_BE(), not used
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Reported-by: Felipe Sateler <fsateler@debian.org>
use (1<<15) instead of 0x7fff as a factor when converting from s16 to float32
use (1<<31) instead of 0x7fffffff as a factor when converting from s32 to float32
the change is motivated by the following desireable properties:
* s16_from_f32(f32_from_s16(x)) == x for all possible s16 values
* x / (1.0f << 15) == x * (1.0f / (1 << 15)) for all x in s16
above changes enable easier optimization while guaranteeing bit-exact results
further, other audio sample conversion code (libavresample) does it the same way
v3 (comments Tanu):
* fix saturation in pa_sconv_s16le_from_f32ne_neon(), use vqrshrn
v2 (comments Tanu):
* fix comments in ARM NEON code
* use llrintf() in pa_sconv_s32le_from_float32ne()
Signed-off-by: Peter Meerwald <p.meerwald@bct-electronic.com>
Cc: Tanu Kaskinen <tanuk@iki.fi>
Get rid of the liboil dependency and reimplement the liboil functions with an
equivalent C implementation. Note that most of these functions are deprecated in
liboil and that none of them had any optimisations. We can further specialize
our handrolled versions for some extra speedups.
