🚀 go-pugleaf

[request for info on intermediate results kept in FP chip]
Trivial answer for Turbo C using 80x87.  It keeps intermediate results of a 
single expression in the '87 as 80 bit values.  Also, all float/double/long 
double functions actually return an 80 bit value in the FP top of stack.

This was a hassle for my Numerical Analysis class, where they wanted us to
show the difference between 32 and 64 bit arithmetic (had to store each 
intermediate result to a memory variable, and reload through an aliased
pointer :->)

Seems to work fine.  Code is simpler (stack-based instructions), results are 
'better' (although numerical analysis people have complained - see above).
Of course, the 387 supposedly runs faster when one of the operands is in
_memory_ as opposed to being in a register!  (Is this because it knows a
memory op is only 32 bits long, so it doesn't need to do the entire 80 bit
operation?  Confusion reigns)
	Don Corbitt, occasional grad student
	Don_A_Corbitt@cup.portal.com