fistp to general purpose reg ?

Reply

Join Date: May 2009
Posts: 5
Reputation: nuliknol is an unknown quantity at this point 
Solved Threads: 0
nuliknol nuliknol is offline Offline
Newbie Poster

fistp to general purpose reg ?

 
0
  #1
Jun 2nd, 2009
Hi,

i have got a new question, is it possible to pop from the FPU stack and deposit to general purpose register without doing FIST to memory?
Or in other words,, is there any way to do
FISTP RAX
or something equivalent? (i can't write to memory because of low speed)
Reply With Quote Quick reply to this message  
Join Date: Mar 2005
Posts: 129
Reputation: Evenbit is on a distinguished road 
Solved Threads: 4
Evenbit's Avatar
Evenbit Evenbit is offline Offline
Junior Poster

Re: fistp to general purpose reg ?

 
1
  #2
Jun 3rd, 2009
Here is a wonderful resource to help you understand the proper use of FPU instructions:

http://webster.cs.ucr.edu/AoA/Window...ic.html#998833
while (CPU is present) {some assembly required}
Reply With Quote Quick reply to this message  
Join Date: May 2009
Posts: 5
Reputation: nuliknol is an unknown quantity at this point 
Solved Threads: 0
nuliknol nuliknol is offline Offline
Newbie Poster

Re: fistp to general purpose reg ?

 
0
  #3
Jun 3rd, 2009
Originally Posted by Evenbit View Post
Here is a wonderful resource to help you understand the proper use of FPU instructions:

http://webster.cs.ucr.edu/AoA/Window...ic.html#998833
ohh i see. so this relic can't move from general purpose reg to its stack because the stack is 64 bit long (well, actualy 80 bits long) and this thing was made in late 1970s , wow!
I hope that now all the micros are 64 bits, Intel reconsiders and adds direct move instructions to the stack , because if the FPU is good for something, it is for storage, almost 512 bits there on the regs, And regarding the calcs, you do it on XMMs, much faster
Reply With Quote Quick reply to this message  
Reply

This thread is more than three months old.
Perhaps start a new thread instead?
Message:



Similar Threads
Other Threads in the Assembly Forum
Thread Tools Search this Thread



About Us | Contact Us | Advertise | DaniWeb | Acceptable Use Policy | RSS Feed

©2003 - 2009 DaniWeb® LLC