Re: [Tinycc-devel] The inline assembly clobber for floating point register stack `%st' not implemented?

[YX Hao]

Hi,

This serial of functions in 'math.h' all use "st":
http://en.cppreference.com/w/c/numeric/math/rint
and
http://blogs.msdn.com/b/vcblog/archive/2013/07/19/c99-library-support-in-visual-studio-2013.aspx

----- Original Message ----- 
From: "Sergey Korshunoff" <address@hidden>
Sent: Tuesday, January 20, 2015 4:41 PM


I'm assumed that "st" register can be considered  by tcc as "memory"
specification. This assumption allowed me to build a nimrod compiler
for windows. Not tested if it works.

2015-01-19 14:37 GMT+03:00, YX Hao <address@hidden>
> Hi,
>
> From: "Sergey Korshunoff" <address@hidden>
> Sent: Monday, January 19, 2015 1:14 AM
>
>
> > Hi! Another question:  Compiling a nimrod compiler by i386-win-tcc I
> > got  the following error:
> > /usr/local/lib/win32/include/math.h:541: error: invalid clobber register
> > 'st'
>
> Go into include/math.h:541:
>
>   __CRT_INLINE long __cdecl lrint (double x)
>   {
>     long retval;
>     __asm__ __volatile__             \
>       ("fistpl %0"  : "=m" (retval) : "t" (x) : "st");          \
>       return retval;
>   }
>
> __asm__　__volatile__("Instruction List" : Output : Input : 
> Clobber/Modify);
>
> Guide to Inline Assembly:
> http://www.delorie.com/djgpp/doc/brennan/brennan_att_inline_djgpp.html
> Clobber List:
> http://www.ibiblio.org/gferg/ldp/GCC-Inline-Assembly-HOWTO.html#ss5.3
> st:
> http://sourceware.org/binutils/docs-2.25/as/i386_002dRegs.html#i386_002dRegs
>
> Anyone know more abount it?