static SoftFloat sbr_sum_square_c(int (*x)[2], int n)
{
SoftFloat ret;
- uint64_t accu = 0, round;
- int i, nz;
+ uint64_t accu, round;
+ uint64_t accu0 = 0, accu1 = 0, accu2 = 0, accu3 = 0;
+ int i, nz, nz0;
unsigned u;
for (i = 0; i < n; i += 2) {
// Larger values are inavlid and could cause overflows of accu.
- av_assert2(FFABS(x[i + 0][0]) >> 29 == 0);
- accu += (int64_t)x[i + 0][0] * x[i + 0][0];
- av_assert2(FFABS(x[i + 0][1]) >> 29 == 0);
- accu += (int64_t)x[i + 0][1] * x[i + 0][1];
- av_assert2(FFABS(x[i + 1][0]) >> 29 == 0);
- accu += (int64_t)x[i + 1][0] * x[i + 1][0];
- av_assert2(FFABS(x[i + 1][1]) >> 29 == 0);
- accu += (int64_t)x[i + 1][1] * x[i + 1][1];
+ av_assert2(FFABS(x[i + 0][0]) >> 30 == 0);
+ accu0 += (int64_t)x[i + 0][0] * x[i + 0][0];
+ av_assert2(FFABS(x[i + 0][1]) >> 30 == 0);
+ accu1 += (int64_t)x[i + 0][1] * x[i + 0][1];
+ av_assert2(FFABS(x[i + 1][0]) >> 30 == 0);
+ accu2 += (int64_t)x[i + 1][0] * x[i + 1][0];
+ av_assert2(FFABS(x[i + 1][1]) >> 30 == 0);
+ accu3 += (int64_t)x[i + 1][1] * x[i + 1][1];
}
+ nz0 = 15;
+ while ((accu0|accu1|accu2|accu3) >> 62) {
+ accu0 >>= 1;
+ accu1 >>= 1;
+ accu2 >>= 1;
+ accu3 >>= 1;
+ nz0 --;
+ }
+ accu = accu0 + accu1 + accu2 + accu3;
+
u = accu >> 32;
- if (u == 0) {
- nz = 1;
- } else {
- nz = -1;
+ if (u) {
+ nz = 33;
while (u < 0x80000000U) {
u <<= 1;
- nz++;
+ nz--;
}
- nz = 32 - nz;
- }
+ } else
+ nz = 1;
round = 1ULL << (nz-1);
u = ((accu + round) >> nz);
u >>= 1;
- ret = av_int2sf(u, 15 - nz);
+ ret = av_int2sf(u, nz0 - nz);
return ret;
}