swscale: add padding to conversion buffer.

Altivec does unaligned reads from this buffer in
hscale_altivec_real(), and can thus read up to 16 bytes beyond
the end of the buffer. Therefore, add an extra 16 bytes of
padding at the end of the conversion buffer.

This fixes fate-lavfi-pixfmts_scale on AltiVec-enabled builds
under valgrind.

Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
This commit is contained in:
Sean McGovern 2011-11-10 19:16:58 -05:00 committed by Ronald S. Bultje
parent b8a1b880ee
commit 124e56454d

View File

@ -871,7 +871,7 @@ int sws_init_context(SwsContext *c, SwsFilter *srcFilter, SwsFilter *dstFilter)
if (c->dstBpc == 16)
dst_stride <<= 1;
FF_ALLOC_OR_GOTO(c, c->formatConvBuffer,
FFALIGN(srcW, 16) * 2 * FFALIGN(c->srcBpc, 8) >> 3,
(FFALIGN(srcW, 16) * 2 * FFALIGN(c->srcBpc, 8) >> 3) + 16,
fail);
if (HAVE_MMX2 && cpu_flags & AV_CPU_FLAG_MMX2 && c->srcBpc == 8 && c->dstBpc <= 10) {
c->canMMX2BeUsed= (dstW >=srcW && (dstW&31)==0 && (srcW&15)==0) ? 1 : 0;