inline asm (Fasm) with C++

[agathes]

Good morning everyone,

Kindly be of some form of assistance to me. Here is what I wanted to know.
I know some c++, done some win32, and some normal projects, now here is an issue bothering me, can you do _asm (inline Asm) in c++ using FASM?

This has been an issue I have been working / thinking on. Can you be of assistance of some sort.

Waiting for your Replies.

[MiiNiPaa]

can you do [...] inline Asm

Yes. However it is compiler dependend. I believe Intel compiler can use FASM. Gcc uses gas and can switch between AT&T and Intel syntax. MSVS uses Microsoft assembler and Intel syntax.

Example of GCC inline assembler with AT&T syntax and resulting code (with ((noinline)) attribute on for testing):

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inline uint64_t processorTicks() { uint64_t tt; asm volatile ( "rdtsc;" "shl $32, %%rdx;" "or %%rdx, %%rax;" :"=a"(tt) : :"%rdx" ); return tt; }

0x00401640 rdtsc 0x00401642 shl $0x20,%rdx 0x00401646 or %rdx,%rax 0x00401649 retq