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+--- Thread: Hardware square root gcc (/Thread-Hardware-square-root-gcc)
Hardware square root gcc - philliepgmkygi - 07-24-2023
I'm trying to use the hardware instructions to compute some mathematical functions. For example the square root (sqrtpd instruction). I'm compiling my C code with GCC.
Does Anybody know what are the gcc options to force to compile with the hardware instructions and not to use the libc? Or if I need to do something special on my source code? (Without writing asm code).
RE: Hardware square root gcc - chamois256 - 07-24-2023
On gcc you should use `__builtin_ia32_sqrtpd`.
RE: Hardware square root gcc - strewn699342 - 07-24-2023
The easiest way is to use optimization flags. -O1 generates
`sqrtsd %xmm1, %xmm0`
in assembly code. Try using -S flag with gcc to generate assembly and look how optimization flags works.
RE: Hardware square root gcc - silsby383 - 07-24-2023
Why don't you just write the desired hardware instruction in assembly code directly.
As far as I know, writing assembly code directly in c code is possible. It is called Inline Assembly. [ See here:
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