On 2017-06-11 11:34, Ivan Kalvachev wrote: > On 6/10/17, James Darnley <james.darn...@gmail.com> wrote: >> On 2017-06-09 13:41, Ivan Kalvachev wrote: >>> >>> const_*_edge is used on only one place is the code. >>> Would you check if this patch fixes the issue. >>> >>> I expected that the addresses would be pre-calculated >>> by n/yasm as one value and indexed >>> relative to the section start. >>> Instead it seems that each entry is represented with >>> its own address and offset from it. >>> Since the offset is negative it uses all 64 bits and >>> it makes difference if it is truncated to 32 bits. >>> >>> Same issue could happen with clang tools. >> >> The problem is with the relative addressing. You need to load the real >> address first before you can offset with another register at runtime. So >> something like: >> >>> mov reg1, [read_only_const] > lea ?
Yes, sorry about that. > ====== > --- a/libavcodec/x86/opus_pvq_search.asm > +++ b/libavcodec/x86/opus_pvq_search.asm > @@ -406,7 +406,7 @@ align 16 > ; uint32 N - Number of vector elements. Must be 0 < N < 8192 > ; > %macro PVQ_FAST_SEARCH 0 > -cglobal pvq_search,4,5,8, mmsize, inX, outY, K, N > +cglobal pvq_search,4,6,8, mmsize, inX, outY, K, N > %define tmpX rsp > > ; movsxdifnidn Nq, Nd > @@ -419,7 +419,12 @@ cglobal pvq_search,4,5,8, mmsize, inX, outY, K, N > add Nq, r4q ; Nq = align(Nq, mmsize) > sub rsp, Nq ; allocate tmpX[Nq] > > +%ifdef PIC > + lea r5q, [const_align_abs_edge] ; rip+const > + movups m3, [r5q+r4q-mmsize] ; this is the > bit mask for the padded read at the end of the input > +%else > movups m3, [const_align_abs_edge-mmsize+r4q] ; this is the > bit mask for the padded read at the end of the input > +%endif > > lea r4q, [Nq-mmsize] ; Nq is rounded up (aligned up) to > mmsize, so r4q can't become negative here, unless N=0. > movups m2, [inXq + r4q] > ====== FYI that diff works just fine, when I correct the line wrapping. I can compile and run on Win64. This is not a comment about the original patch. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
