C/C++ Inline Assembler with Instructions in String Variables

Can't execute inline assembler with the instructions in a string variable

The instructions must be in a form of a string literal(actual written string, the name of a char array is a pointer btw).
Other than that you got the general idea:)

#include <stdio.h>

int main(int argc, char ** argv){
char a[20] = "nice try:)";
char * dst;

asm("mov %[dst], %[src]\n\t"
    : [dst]"=r" (dst) : [src]"r"(a));

printf("%s\n", dst);
return 0;
}

and a useful link:
https://dmalcolm.fedorapeople.org/gcc/2015-08-31/rst-experiment/how-to-use-inline-assembly-language-in-c-code.html

Can I use asm function with a c - string variable instead of a string literal as an argument?

As far as I know asm code fragment are inlined during compilation phase, not run-time. Which means you can't do what you are doing.

As pmg suggested, you could do it by calling external commands, but it would mean user would need to have all the tools installed.

How to use a String in C++ Inline Assembly code?

The Visual C++ compiler allows you to use variables directly in assembly code. Example from here: http://msdn.microsoft.com/en-us/library/y8b57x4b(v=vs.80).aspx

// InlineAssembler_Calling_C_Functions_in_Inline_Assembly.cpp
// processor: x86
#include <stdio.h>

char format[] = "%s %s\n";
char hello[] = "Hello";
char world[] = "world";
int main( void )
{
   __asm
   {
      mov  eax, offset world
      push eax
      mov  eax, offset hello
      push eax
      mov  eax, offset format
      push eax
      call printf
      //clean up the stack so that main can exit cleanly
      //use the unused register ebx to do the cleanup
      pop  ebx
      pop  ebx
      pop  ebx
   }
}

It doesn't get any easier than this, IMO. You get all the speed, without all the hassle of trying to find out where variables are stored.

How to inline assembly code using bits (hard code) in C?

You can put raw bytes in with .byte:

__asm__ (".byte 0xf0, 0x0b, 0xaa");

Add variable in assembly instruction (asm inline C example)

You can read something like this and this

static inline void cpuid(int code, uint32_t *a, uint32_t *d) {
  asm volatile("cpuid":"=a"(*a),"=d"(*d):"a"(code):"ecx","ebx");
}

/** issue a complete request, storing general registers output as a string
 */
static inline int cpuid_string(int code, uint32_t where[4]) {
  asm volatile("cpuid":"=a"(*where),"=b"(*(where+1)),
               "=c"(*(where+2)),"=d"(*(where+3)):"a"(code));
  return (int)where[0];
}