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;***;; Copyright (c) 1984-2001, Microsoft Corporation. All rights reserved.;;Revision History:;;*******************************************************************************
.xlist include cruntime.inc include elem87.inc.list .conststaticQ One, 03FF0000000000000RglobalW _DEFAULT_CW_in_mem 027fhglobalT _pi_by_2_to_61 0403ec90fdaa22168c235R ; (2**61) * pistaticQ DblMax, 07fefffffffffffffRstaticQ DblMin, 00010000000000000RstaticQ IeeeAdjO, 0c098000000000000RstaticQ IeeeAdjU, 04098000000000000RstaticQ _infinity, 07ff0000000000000RstaticQ _zero, 00000000000000000R
CODESEG
extrn _startOneArgErrorHandling:nearextrn _startTwoArgErrorHandling:near
;***********************************************************;; _twoToTOS;;***********************************************************; Recieves:; TOS is not NaN; Retunns:; 2^TOS; Note:; uses 3 entries of FPU stack
_twoToTOS proc fld st(0) ; duplicate stack top frndint ; N = round(y) fsubr st(1), st fxch fchs ; g = y - N where abs(g) < 1 f2xm1 ; 2**g - 1 fld1 fadd ; 2**g fscale ; (2**g) * (2**N) - gives 2**y fstp st(1) ret ; pop extra stuff from fp stack_twoToTOS endp
;***********************************************************;; _load_CW;;***********************************************************; receives current control word on stack; and it's known that it differs from default; Purpose:; load default CW, but take precision from current CW (bits 8 and 9); Note:; value of edx is destroyed;_load_CW proc mov edx,[esp+4] and edx,0300H ; all bits except precision are zero or edx,DEFAULT_CW_without_precision mov [esp+6],dx ; use 2 free bytes in stack fldcw [esp+6] ret_load_CW endp
;***********************************************************;; _convertTOStoQNaN;;***********************************************************; Recieves:; TOS is QNaN or SNaN; eax is high dword of TOS; Retunns:; if TOS=QNaN; eax=DOMAIN_QNAN; else (TOS=SNaN); eax=DOMAIN; TOS=QNaN
_convertTOStoQNaN proc test eax, 00080000H ; test weather arg is QNaN or SNaN jz tosIsSNaN mov eax,DOMAIN_QNAN ; TOS is QNaN rettosIsSNaN: fadd [One] ; convert SNaN to QNan mov eax,DOMAIN ; TOS was SNaN ret ; _cdecl return
_convertTOStoQNaN endp
;***********************************************************;; _fload_withFB;;***********************************************************; Load arg in the fp stack without raising an exception if the argument; is a signaling NaN; In other words, when arg is 53-bit SNaN convert it to 64-bit SNaN;; edx points to argument (in double precision); return value:; if we have normal number:; eax=exponent; Zero flag is 0; if we have special number:; eax=high dword; Zero flag is 1
_fload_withFB proc ; load with feed back mov eax, [edx+4] ; get exponent field and eax, 07ff00000h cmp eax, 07ff00000h ; check for special exponent je fpload_special fld qword ptr[edx] ; ZF=0 ret ; _cdecl return
; have special argument (NaN or INF)fpload_special: ; convert to long double mov eax,[edx+4] ; high dword of double sub esp,LDBLSIZE or eax, 7fff0000h ; preserve sign, set max long double exp mov [esp+6],eax ; store sign and power mov eax,[edx+4] ; low dword of double mov ecx,[edx] shld eax,ecx,11 shl ecx,11
mov [esp+4],eax mov [esp],ecx fld tbyte ptr [esp] add esp,LDBLSIZE test eax,0 ; ZF=1 mov eax,[edx+4] ; high dword of double
ret ; _cdecl return_fload_withFB endp
;***********************************************************;; _checkTOS_withFB;;***********************************************************; Test first argument on INTEGER stack and set registers and flags exactly like _fload_withFB;; we have on stack : ret_value(4 bytes), arg1(8 bytes); return value:; if we have normal number:; eax=exponent; Zero flag is 0; if we have special number:; eax=high dword; Zero flag is 1
_checkTOS_withFB proc mov eax, [esp+8] ; get high dword and eax,07ff00000h cmp eax,07ff00000h ; check for special exponent ; and set ZF je special_exp ret ; _cdecl returnspecial_exp: mov eax, [esp+8] ; get exponent field ret ; _cdecl return
_checkTOS_withFB endp
;***********************************************************;; _fast_exit;;***********************************************************; called after execution of each math function (sin,cos, ....),; and if __fastflag!=0;_fast_exit proc cmp word ptr[esp],default_CW je fast_exit_CW_is_restored fldcw [esp]fast_exit_CW_is_restored: pop edx ; remove saved CW from stack ret ; _cdecl return_fast_exit endp
;***********************************************************;; _math_exit;;***********************************************************; called after execution of each math function (sin,cos, ....); and if __fastflag=0.; The purpose is to check inexact exception.; ecx points to function name; edx function id (for example OP_LOG)
_math_exit proc mov ax,word ptr[esp] cmp ax,default_CW je CW_is_restored ; we assume here that in default CW inexact ; exception is masked and ax,20h ; test if inexact exception is masked jz restore_CW fstsw ax and ax,20h jz restore_CW mov eax,INEXACT call _startOneArgErrorHandling pop edx ; remove saved CW from stack retrestore_CW: fldcw [esp]CW_is_restored: pop edx ; remove saved CW from stack ret ; _cdecl return_math_exit endp
;***********************************************************;; _check_overflow_exit;;***********************************************************;_check_overflow_exit proc sub esp,DBLSIZE ; prepare place for argument fst qword ptr[esp] mov eax,[esp+4] ; eax=high dword add esp,DBLSIZE and eax,7ff00000H jmp _check_overflow_start_check_overflow_exit endp
;***********************************************************;; _check_range_exit;;***********************************************************; called after execution of math functions, which may generate; overflow/underflow, and if __fastflag=0.; used in exp() and pow() functions; The purpose is to check inexact overflow/underflow and inexact exception; ecx points to function name; edx function id (for example OP_EXP)
_check_range_exit proc sub esp,DBLSIZE ; prepare place for argument fst qword ptr[esp] mov eax,[esp+4] ; eax=high dword add esp,DBLSIZE and eax,7ff00000H jz haveunderflow_check_overflow_start label proc cmp eax,7ff00000H jz haveoverflow
; check INEXACT(precision) exception mov ax,word ptr[esp] ; saved CW cmp ax,default_CW je CW_is_restored ; we assume here that in default CW inexact ; exception is masked and ax,20h ; test if inexact exception is masked jnz restore_CW fstsw ax and ax,20h jz restore_CW mov eax,INEXACThave_error: cmp edx,OP_POW je have_error_in_pow call _startOneArgErrorHandling pop edx ; remove saved CW from stack rethave_error_in_pow: call _startTwoArgErrorHandling pop edx ; remove saved CW from stack ret
restore_CW: fldcw [esp]CW_is_restored: pop edx ; remove saved CW from stack ret ; _cdecl return
; this code is taken from previous version, to receive; exactly the same result as before. But we may simplify it...haveunderflow: ; underflow is detected fld IeeeAdjU fxch fscale fstp st(1) fld st(0) fabs fcomp [DblMin] fstsw ax sahf mov eax,UNDERFLOW JSAE have_error fmul [_zero] jmp short have_error
haveoverflow: ; overflow is detected fld IeeeAdjO fxch fscale fstp st(1) fld st(0) fabs fcomp [DblMax] fstsw ax sahf mov eax,OVERFLOW JSBE have_error fmul [_infinity] jmp short have_error
_check_range_exit endp end
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