[Ffmpeg-devel] No llrint() in Cygwin

[Víctor Paesa]

Hi,


> Vi?ctor Paesa said:
>> Hi,
>>>
>>> SVN r6290 brought llrint(), but that function is not defined in Cygwin
>>> (because it uses newlib for math.h).
>>>
>>> I found this LGPL code that defines llrint() as inline for x86:
>>>
>>> http://sourceware.org/ml/cygwin/2002-12/msg01146/mathinline.h
>>>
>>> Would it be acceptable to copy that llrint() implementation
>>> into libavcodec/i386/mathops.h ?
>>>
>>
>> Maybe this patch will ignite some comments:
>>
>> ===================================================================
>> --- ffmpeg/libavcodec/i386/mathops.h    (revision 6329)
>> +++ ffmpeg/libavcodec/i386/mathops.h    (working copy)
>> @@ -37,3 +37,16 @@
>>       asm ("imull %2\n\t" : "=A"(rt) : "a" (ra), "g" (rb));\
>>       rt; })
>>
>> +#ifndef llrint
>> +#define __llrint_code \
>> +    long long int __llrintres;\
>> +    __asm__ \
>> +    ("fistpll %0" \
>> +    : "=m" (__llrintres) : "t" (__x) : "st"); \
>> +    return __llrintres
>> +
>> +__inline long long int llrint (double __x)
>> +{
>> +    __llrint_code;
>> +}
>> +#endif
>
> Identifiers starting with __ are reserved for the system.

OK

> What's the purpose of the macro?

In the original code it had a meaning, the macro was
reused by llrint(), llrintf(), llrintl().
Since I'm not familiar at all with inline assembler
I tried to minimize changes.

What about this new version:

===================================================================
--- ffmpeg/libavcodec/i386/mathops.h    (revision 6329)
+++ ffmpeg/libavcodec/i386/mathops.h    (working copy)
@@ -37,3 +37,13 @@
      asm ("imull %2\n\t" : "=A"(rt) : "a" (ra), "g" (rb));\
      rt; })

+#ifndef llrint
+inline long long int llrint (double x)
+{
+    long long int llrintres;
+    asm
+    ("fistpll %0"
+    : "=m" (llrintres) : "t" (x) : "st");
+    return llrintres;
+}
+#endif


Thanks for your review,
V?ctor Paesa
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ffmpeg.cygwin.llrint.2.diff
Type: text/x-patch
Size: 503 bytes
Desc: not available
URL: <http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/attachments/20060926/fc14cdeb/attachment.bin>