33 static int ssd_int8_vs_int16_altivec(
const int8_t *pix1,
const int16_t *pix2,
36 int i, size16 = size >> 4;
37 vector
signed char vpix1;
38 vector
signed short vpix2, vdiff, vpix1l, vpix1h;
40 vector
signed int vscore;
42 }
u = { .vscore = vec_splat_s32(0) };
48 vpix1 = vec_unaligned_load(pix1);
49 vpix2 = vec_unaligned_load(pix2);
52 vpix1h = vec_unpackh(vpix1);
53 vdiff = vec_sub(vpix1h, vpix2);
54 vpix1l = vec_unpackl(vpix1);
56 vpix2 = vec_unaligned_load(pix2);
57 u.vscore = vec_msum(vdiff, vdiff,
u.vscore);
58 vdiff = vec_sub(vpix1l, vpix2);
59 u.vscore = vec_msum(vdiff, vdiff,
u.vscore);
64 u.vscore = vec_sums(
u.vscore, vec_splat_s32(0));
67 for (i = 0; i <
size; i++)
68 u.score[3] += (pix1[i] - pix2[i]) * (pix1[
i] - pix2[
i]);
Macro definitions for various function/variable attributes.
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
#define u(width, name, range_min, range_max)
#define PPC_ALTIVEC(flags)
int(* ssd_int8_vs_int16)(const int8_t *pix1, const int16_t *pix2, intptr_t size)
av_cold void ff_svq1enc_init_ppc(SVQ1EncContext *c)
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Contains misc utility macros and inline functions.