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vc2enc: properly promote operations to 64 bits 

On Windows machines, the UL suffix still means 32 bits.
The only parts that need 64 bits are (1ULL << (m + 32)) and
(t*qf + qf). Hence, use the proper ULL suffix for the former
and just increase the type of the qf constant for the latter.
No overflows can happen as long as these are done in 64 bits and
the quantization table doesn't change.

Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
This commit is contained in:
Rostislav Pehlivanov 2018-03-12 23:31:22 +00:00
parent 040b28aecc
commit 688060fbb7
1 changed files with 5 additions and 5 deletions
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10
libavcodec/vc2enc.c
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@ -1163,14 +1163,14 @@ static av_cold int vc2_encode_init(AVCodecContext *avctx)
goto alloc_fail; goto alloc_fail;
for (i = 0; i < 116; i++) { for (i = 0; i < 116; i++) {
const uint32_t qf = ff_dirac_qscale_tab[i]; const uint64_t qf = ff_dirac_qscale_tab[i];
const int m = av_log2(qf); const uint32_t m = av_log2(qf);
const uint32_t t = (1UL << (m + 32)) / qf; const uint32_t t = (1ULL << (m + 32)) / qf;
const uint32_t r = (t*qf + qf) & ((1UL << 32) - 1); const uint32_t r = (t*qf + qf) & UINT32_MAX;
if (!(qf & (qf - 1))) { if (!(qf & (qf - 1))) {
s->qmagic_lut[i][0] = 0xFFFFFFFF; s->qmagic_lut[i][0] = 0xFFFFFFFF;
s->qmagic_lut[i][1] = 0xFFFFFFFF; s->qmagic_lut[i][1] = 0xFFFFFFFF;
} else if (r <= 1UL << m) { } else if (r <= 1 << m) {
s->qmagic_lut[i][0] = t + 1; s->qmagic_lut[i][0] = t + 1;
s->qmagic_lut[i][1] = 0; s->qmagic_lut[i][1] = 0;
} else { } else {