Is it correct to perform a function call like this?

Question

I have an array with 32bit values (nativeParameters with length nativeParameterCount) and a pointer to the function (void* to a cdecl function, here method->nativeFunction) thats supposed to be called. Now I'm trying to do this:

// Push parameters for call
if (nativeParameterCount != 0) {
    uint32_t count = 0;
pushParameter:
    uint32_t value = nativeParameters[nativeParameterCount - count - 1];
            asm("push %0" : : "r"(value));
    if (++count < nativeParameterCount) goto pushParameter;
}

// Call method
asm("call *%0" : : "r"(method->nativeFunction));

// Return value
uint32_t eax;
uint32_t edx;
asm("push %eax");
asm("push %edx");
asm("pop %0" : "=r"(edx));
asm("pop %0" : "=r"(eax));
uint64_t returnValue = eax;

// If the typesize of the methods return type is >4 bytes, or with EDX
Type returnType = method->returnType.type;
if (TYPE_SIZES[returnType] > 4) {
    returnValue |= (((uint64_t) edx) << 32);
}

// Clean stack
asm("add %%esp, %0" : : "r"(parameterByteSize));

Is this approach suitable to perform a native call (assuming that all target functions accept only 32bit values as parameters)? Can I be sure that it doesn't destroy the stack or mess with registers, or somehow else influence the normal flow? Also, are there other ways of doing this?

Answer 1

Instead of doing this manually yourself, you might want to use the dyncall libary which does all this handling for you.