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Re: [Gcl-devel] [Maxima] Out of range floating point number determinatio
Re: [Gcl-devel] [Maxima] Out of range floating point number determination
Tue, 02 Oct 2012 15:14:52 -0400
Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux)
Raymond Toy <address@hidden> writes:
> On 9/7/12 11:45 AM, Camm Maguire wrote:
> Sorry for the delay! I missed the message earlier.
>> You mention that some implementations disassemble the faulting
>> instruction to get at the operands. I'm wondering if I could do this
>> with Linux's ucontext_t structure, containing fpregs and __fpregs_mem.
> Yes, this is what cmucl does, more or less. You could look there for an
> idea of how to do this. Look at src/code/x86-vm.lisp
One other question, in the local fun
;; Look at the byte and see what kind of operation is
(cdr (assoc x '((#x58 . +) (#x59 . *) (#x5c . -) (#x5e . /)))))
you associate #x5e with /, but I get
0x08806681: dc 75 e8 fdivl -0x18(%ebp)
=> 0x08806684: dd 1c 24 fstpl (%esp)
which shows as #475 in the $fop register. This value appeared to make
sense from the intel docs last I looked.
Camm Maguire address@hidden
"The earth is but one country, and mankind its citizens." -- Baha'u'llah