inline-assembly

This question already has an answer here: How to invoke a system call via sysenter in inline assembly? 2 answers I'm trying to use inline assembly... I read this page http://www.codeproject.com/KB/cpp/edujini_inline_asm.aspx but I can't understand the parameters passing to my function. I'm writing a C write example.. this is my function header: write2(char *str, int len){ } And this is my assembly code: global write2 write2: push ebp mov ebp, esp mov eax, 4 ;sys_write mov ebx, 1 ;stdout mov ecx, [ebp+8] ;string pointer mov edx, [ebp+12] ;string size int 0x80 ;syscall leave ret What do I have

We are writing a byte-code for a high-level compiled language, and after a bit of profiling and optimization, it became clear that the current largest performance overhead is the switch statement we're using to jump to the byte-code cases. We investigated pulling out the address of each case label and storing it in the stream of byte-code itself, rather than the instruction ID that we usually switch on. If we do that, we can skip the jump table, and directly jump to the location of code of the currently executing instruction. This works fantastically in GCC, however, MSVC doesn't seem to

Why doesn't this code set temp to 1? How do I actually do that? int temp; __asm__( ".intel_syntax;" "mov %0, eax;" "mov eax, %1;" ".att_syntax;" : : "r"(1), "r"(temp) : "eax"); printf("%d\n", temp); You want temp to be an output, not an input, I think. Try: __asm__( ".intel_syntax;" "mov eax, %1;" "mov %0, eax;" ".att_syntax;" : "=r"(temp) : "r"(1) : "eax"); This code does what you are trying to achieve. I hope this helps you: #include <stdio.h> int main(void) { /* Compile with C99 */ int temp=0; asm ( ".intel_syntax;" "mov %0, 1;" ".att_syntax;" : "=r"(temp) : /* no input*/ ); printf("temp=%d