shift.esm

来自「开放源码的编译器open watcom 1.6.0版的源代码」· ESM 代码 · 共 67 行

.387
.386p
		PUBLIC	__sqrtd
		PUBLIC	__sqrt
		PUBLIC	__FDLD
		PUBLIC	__LDFD
_TEXT		SEGMENT	DWORD PUBLIC USE32 'CODE'
		ASSUME CS:_TEXT, DS:DGROUP, SS:DGROUP
__sqrtd:
    push        ebx
    sub         esp,0cH
    mov         ebx,esp
    call        near ptr __FDLD
    mov         eax,esp
    call        near ptr __sqrt
    mov         eax,esp
    call        near ptr __LDFD
    add         esp,0cH
    pop         ebx
    ret         
__Exception_HNDLR:
    ret         
__sqrt:
    add         cx,cx
    add         cx,cx
    shr         cx,1
    add         edx,edx
    sar         cx,1
    shr         edx,1
    rcr         ebx,1
    rcr         edi,1
    rcr         esi,1
    rcr         esi,1
    rcr         esi,1
    rcr         eax,1
    ret         
__FDLD:
    shld        edx,eax,0bH
    shl         eax,0bH
    sar         ecx,14H
    add         eax,eax
    adc         edx,edx
    add         ecx,ecx
    rcr         cx,1
    ret         
__LDFD:
    shl         ebx,16H
    shrd        eax,edx,0cH
    add         edx,edx
    shr         edx,0cH
    shrd        eax,edx,0bH
    add         edx,edx
    shrd        edx,ecx,0bH
    add         bx,bx
    rcr         edx,1
    shrd        esi,eax,cl
    shrd        eax,edx,cl
    shr         edx,cl
    shrd        eax,edx,0bH
    add         edx,edx
    shr         edx,0bH
    add         bx,bx
    rcr         edx,1
    ret         
_TEXT		ENDS
		END