内联asm

Question

我必须使用内联asm找到两点之间的距离，但是我被卡住了，因为加上两个坐标差异的幂后我得到的数字对于32位寄存器来说太大了。

#include <stdio.h>


void main()
{
// Input
unsigned int Point = 0xFFFFFFFF;
unsigned int PointSet = 0x000A0003
unsigned int dist=0;
/*
every point is a dword and the least significant word is the x coord while the other is the y coord
so for our point it would be (3,10) in decimal and the other point (FFFF,FFFF)
*/

//sqrt((x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1));
 __asm
{
    xor eax,eax
    mov eax, dword ptr PointSet[0]
    shr eax,16d //ax is x1
    xor ebx,ebx
    mov bx, word ptr PointSet[0] //bx is y1
    mov ecx, 0xFFFF //x2
    mov edx, 0xFFFF//y2
    sub ecx,eax //(x2-x1)
    sub edx,ebx //(y2-y1)
    imul ecx,ecx //(x2-x1)^2
    imul edx,edx //(x2-x1)^2
    add ecx,edx  //here the number is way too big to stay in a simple 32 bit register
    push esp
    mov  dword ptr[esp], ecx
    fild  dword ptr[esp]
    fsqrt
    fst dword ptr[esp]
    mov ecx,esp

}
printf("%d",dist);
getchar();


}