On Sun, Feb 20, 2011 at 10:09:46PM +0000, Peter Maydell wrote: > On 20 February 2011 21:52, Aurelien Jarno <aurel...@aurel32.net> wrote: > > On Fri, Feb 18, 2011 at 03:49:15PM +0100, Christophe Lyon wrote: > > >> +#define float64_half make_float64(0x3fe0000000000000LL) > >> +#define float64_256 make_float64(0x4070000000000000LL) > >> +#define float64_512 make_float64(0x4080000000000000LL) > >> > >> /*---------------------------------------------------------------------------- > >> | The pattern for a default generated double-precision NaN. > > > > While it's probably a good idea to define the commonly used values in > > softfloat.h, I don't think we should have all the values used by the > > different targets here. Infinity, one, half, two probably have their > > place here, I don't think it's the case of 256 and 512. It should be > > better to defined them at the target level. > > Are you happy with targets just doing make_float*() on a > bit pattern? I guess that's the most straightforward thing,
Yes, I think it is the way to go. > although at the moment the target-arm code seems to prefer > float32 three = int32_to_float32(3, s); > I don't care very much personally as long as we're not doing > a runtime division to get a constant 0.5 :-) Doing that at runtime is clearly not a good solution. > Incidentally, if you're up for some target-mips cleanup: > target-mips/op_helper.c:#define FLOAT_ONE32 make_float32(0x3f8 << 20) > > could be using float32_one instead. (ditto for float64). Yes, one is a really common value among target, and in my opinion we should keep it in softfloat.h. I have a local patch that does this cleanup and also moves the constant 2 to softfloat.h. I'll submit it one day with other mips softfloat cleanup. > > Also for consistency, I > > think it's better to define these value for all float size, or at least > > for all the common ones (32, 64, maybe 16). > > I wouldn't bother with 16, only ARM uses that and only for > conversions to other formats. > That's true, so let's do it float 32 and 64. -- Aurelien Jarno GPG: 1024D/F1BCDB73 aurel...@aurel32.net http://www.aurel32.net
