This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: IA32: printing FP register variables
- To: Jim Blandy <jimb at cygnus dot com>
- Subject: Re: IA32: printing FP register variables
- From: Jeffrey A Law <law at cygnus dot com>
- Date: Sat, 10 Jul 1999 17:30:46 -0600
- cc: "Ben Combee" <bcombee at metrowerks dot com>, egcs at egcs dot cygnus dot com, gdb at sourceware dot cygnus dot com
- Reply-To: law at cygnus dot com
In message <np3dyxu2ua.fsf@zwingli.cygnus.com>you write:
> I don't have an MMX manual handy, but it seems like a much easier case
> than the FPU, since the registers don't shift around every time you do
> an operation.
Correct. While the MMX registers are overloaded on the FPU registers,
they do not stack like FP operations do.
> Well, the reason this problem seems hard to me is exactly because the
> position of items relative to the top of the stack *will* change,
> whenever you execute instructions like FILD, FDIVP, etc. If they were
> a constant distance, then we could simply assign register numbers to
> ST(0) -- ST(7) in the usual way, and everything would work.
Precisely.
jeff