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)

Here is a wonderful resource to help you understand the proper use of FPU instructions:

http://webster.cs.ucr.edu/AoA/Windows/HTML/RealArithmetic.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

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.