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void* av_malloc ( unsigned int  size  ) 

Memory allocation of size byte with alignment suitable for all memory accesses (including vectors if available on the CPU). av_malloc(0) must return a non NULL pointer.

Definition at line 45 of file mem.c.

Referenced by ff_mdct_init(), and fft_inits().

    void *ptr;
#if defined (HAVE_MEMALIGN)
    ptr = memalign(16,size);
    /* Why 64? 
       Indeed, we should align it:
         on 4 for 386
         on 16 for 486
       on 32 for 586, PPro - k6-III
       on 64 for K7 (maybe for P3 too).
       Because L1 and L2 caches are aligned on those values.
       But I don't want to code such logic here!
     /* Why 16?
        because some cpus need alignment, for example SSE2 on P4, & most RISC cpus
        it will just trigger an exception and the unaligned load will be done in the
        exception handler or it will just segfault (SSE2 on P4)
        Why not larger? because i didnt see a difference in benchmarks ...
     /* benchmarks with p3
        memalign(64)+1        3071,3051,3032
        memalign(64)+2        3051,3032,3041
        memalign(64)+4        2911,2896,2915
        memalign(64)+8        2545,2554,2550
        memalign(64)+16       2543,2572,2563
        memalign(64)+32       2546,2545,2571
        memalign(64)+64       2570,2533,2558
        btw, malloc seems to do 8 byte alignment by default here
    ptr = malloc(size);
    return ptr;

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