[FFmpeg-cvslog] vc2enc: properly promote operations to 64 bits

[Rostislav Pehlivanov]

ffmpeg | branch: master | Rostislav Pehlivanov <atomnuker at gmail.com> | Mon Mar 12 23:31:22 2018 +0000| [688060fbb7233d9212a92ce171e3b94784f95ca1] | committer: Rostislav Pehlivanov

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 at gmail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=688060fbb7233d9212a92ce171e3b94784f95ca1
---

 libavcodec/vc2enc.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/libavcodec/vc2enc.c b/libavcodec/vc2enc.c
index 2e480ba8d0..d0101e01e4 100644
--- a/libavcodec/vc2enc.c
+++ b/libavcodec/vc2enc.c
@@ -1163,14 +1163,14 @@ static av_cold int vc2_encode_init(AVCodecContext *avctx)
         goto alloc_fail;
 
     for (i = 0; i < 116; i++) {
-        const uint32_t qf = ff_dirac_qscale_tab[i];
-        const int m = av_log2(qf);
-        const uint32_t t = (1UL << (m + 32)) / qf;
-        const uint32_t r = (t*qf + qf) & ((1UL << 32) - 1);
+        const uint64_t qf = ff_dirac_qscale_tab[i];
+        const uint32_t m = av_log2(qf);
+        const uint32_t t = (1ULL << (m + 32)) / qf;
+        const uint32_t r = (t*qf + qf) & UINT32_MAX;
         if (!(qf & (qf - 1))) {
             s->qmagic_lut[i][0] = 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][1] = 0;
         } else {