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Re: Not supporting all rounding modes
On 2012-05-29 at 15:46 +0200, Thomas Schwinge wrote:
> > On the other hand, sysdeps/sh/sh4/fpu/bits/fenv.h proclaims:
> >
> > /* The SH FPU supports all of the four defined rounding modes. We
> > use again the bit positions in the FPU control word as the values
> > for the appropriate macros. */
> > enum
> > {
> > FE_TONEAREST = 0x0,
> > #define FE_TONEAREST FE_TONEAREST
> > FE_TOWARDZERO = 0x1,
> > #define FE_TOWARDZERO FE_TOWARDZERO
> > FE_UPWARD = 0x2,
> > #define FE_UPWARD FE_UPWARD
> > FE_DOWNWARD = 0x3
> > #define FE_DOWNWARD FE_DOWNWARD
> > };
>
> Turns out this is directly from back when Kaz and Yutaka Niibe (CCed)
> added the SH glibc port, twelve years ago. Do you guys happen to
> remember the history about these rounding modes, or would you agree to
> remove FE_UPWARD and FE_DOWNWARD from the list of supported modes? Or,
> does SH-4-based hardware exist that supports all four modes, and we have
> to do this in a more fine-grained fashion?
I don't remember. I agree the removal. Please go ahead.
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