|  | | | 
|  | |	ssin.sa 3.3 7/29/91 | 
|  | | | 
|  | |	The entry point sSIN computes the sine of an input argument | 
|  | |	sCOS computes the cosine, and sSINCOS computes both. The | 
|  | |	corresponding entry points with a "d" computes the same | 
|  | |	corresponding function values for denormalized inputs. | 
|  | | | 
|  | |	Input: Double-extended number X in location pointed to | 
|  | |		by address register a0. | 
|  | | | 
|  | |	Output: The function value sin(X) or cos(X) returned in Fp0 if SIN or | 
|  | |		COS is requested. Otherwise, for SINCOS, sin(X) is returned | 
|  | |		in Fp0, and cos(X) is returned in Fp1. | 
|  | | | 
|  | |	Modifies: Fp0 for SIN or COS; both Fp0 and Fp1 for SINCOS. | 
|  | | | 
|  | |	Accuracy and Monotonicity: The returned result is within 1 ulp in | 
|  | |		64 significant bit, i.e. within 0.5001 ulp to 53 bits if the | 
|  | |		result is subsequently rounded to double precision. The | 
|  | |		result is provably monotonic in double precision. | 
|  | | | 
|  | |	Speed: The programs sSIN and sCOS take approximately 150 cycles for | 
|  | |		input argument X such that |X| < 15Pi, which is the usual | 
|  | |		situation. The speed for sSINCOS is approximately 190 cycles. | 
|  | | | 
|  | |	Algorithm: | 
|  | | | 
|  | |	SIN and COS: | 
|  | |	1. If SIN is invoked, set AdjN := 0; otherwise, set AdjN := 1. | 
|  | | | 
|  | |	2. If |X| >= 15Pi or |X| < 2**(-40), go to 7. | 
|  | | | 
|  | |	3. Decompose X as X = N(Pi/2) + r where |r| <= Pi/4. Let | 
|  | |		k = N mod 4, so in particular, k = 0,1,2,or 3. Overwrite | 
|  | |		k by k := k + AdjN. | 
|  | | | 
|  | |	4. If k is even, go to 6. | 
|  | | | 
|  | |	5. (k is odd) Set j := (k-1)/2, sgn := (-1)**j. Return sgn*cos(r) | 
|  | |		where cos(r) is approximated by an even polynomial in r, | 
|  | |		1 + r*r*(B1+s*(B2+ ... + s*B8)),	s = r*r. | 
|  | |		Exit. | 
|  | | | 
|  | |	6. (k is even) Set j := k/2, sgn := (-1)**j. Return sgn*sin(r) | 
|  | |		where sin(r) is approximated by an odd polynomial in r | 
|  | |		r + r*s*(A1+s*(A2+ ... + s*A7)),	s = r*r. | 
|  | |		Exit. | 
|  | | | 
|  | |	7. If |X| > 1, go to 9. | 
|  | | | 
|  | |	8. (|X|<2**(-40)) If SIN is invoked, return X; otherwise return 1. | 
|  | | | 
|  | |	9. Overwrite X by X := X rem 2Pi. Now that |X| <= Pi, go back to 3. | 
|  | | | 
|  | |	SINCOS: | 
|  | |	1. If |X| >= 15Pi or |X| < 2**(-40), go to 6. | 
|  | | | 
|  | |	2. Decompose X as X = N(Pi/2) + r where |r| <= Pi/4. Let | 
|  | |		k = N mod 4, so in particular, k = 0,1,2,or 3. | 
|  | | | 
|  | |	3. If k is even, go to 5. | 
|  | | | 
|  | |	4. (k is odd) Set j1 := (k-1)/2, j2 := j1 (EOR) (k mod 2), i.e. | 
|  | |		j1 exclusive or with the l.s.b. of k. | 
|  | |		sgn1 := (-1)**j1, sgn2 := (-1)**j2. | 
|  | |		SIN(X) = sgn1 * cos(r) and COS(X) = sgn2*sin(r) where | 
|  | |		sin(r) and cos(r) are computed as odd and even polynomials | 
|  | |		in r, respectively. Exit | 
|  | | | 
|  | |	5. (k is even) Set j1 := k/2, sgn1 := (-1)**j1. | 
|  | |		SIN(X) = sgn1 * sin(r) and COS(X) = sgn1*cos(r) where | 
|  | |		sin(r) and cos(r) are computed as odd and even polynomials | 
|  | |		in r, respectively. Exit | 
|  | | | 
|  | |	6. If |X| > 1, go to 8. | 
|  | | | 
|  | |	7. (|X|<2**(-40)) SIN(X) = X and COS(X) = 1. Exit. | 
|  | | | 
|  | |	8. Overwrite X by X := X rem 2Pi. Now that |X| <= Pi, go back to 2. | 
|  | | | 
|  |  | 
|  | |		Copyright (C) Motorola, Inc. 1990 | 
|  | |			All Rights Reserved | 
|  | | | 
|  | |       For details on the license for this file, please see the | 
|  | |       file, README, in this same directory. | 
|  |  | 
|  | |SSIN	idnt	2,1 | Motorola 040 Floating Point Software Package | 
|  |  | 
|  | |section	8 | 
|  |  | 
|  | #include "fpsp.h" | 
|  |  | 
|  | BOUNDS1:	.long 0x3FD78000,0x4004BC7E | 
|  | TWOBYPI:	.long 0x3FE45F30,0x6DC9C883 | 
|  |  | 
|  | SINA7:	.long 0xBD6AAA77,0xCCC994F5 | 
|  | SINA6:	.long 0x3DE61209,0x7AAE8DA1 | 
|  |  | 
|  | SINA5:	.long 0xBE5AE645,0x2A118AE4 | 
|  | SINA4:	.long 0x3EC71DE3,0xA5341531 | 
|  |  | 
|  | SINA3:	.long 0xBF2A01A0,0x1A018B59,0x00000000,0x00000000 | 
|  |  | 
|  | SINA2:	.long 0x3FF80000,0x88888888,0x888859AF,0x00000000 | 
|  |  | 
|  | SINA1:	.long 0xBFFC0000,0xAAAAAAAA,0xAAAAAA99,0x00000000 | 
|  |  | 
|  | COSB8:	.long 0x3D2AC4D0,0xD6011EE3 | 
|  | COSB7:	.long 0xBDA9396F,0x9F45AC19 | 
|  |  | 
|  | COSB6:	.long 0x3E21EED9,0x0612C972 | 
|  | COSB5:	.long 0xBE927E4F,0xB79D9FCF | 
|  |  | 
|  | COSB4:	.long 0x3EFA01A0,0x1A01D423,0x00000000,0x00000000 | 
|  |  | 
|  | COSB3:	.long 0xBFF50000,0xB60B60B6,0x0B61D438,0x00000000 | 
|  |  | 
|  | COSB2:	.long 0x3FFA0000,0xAAAAAAAA,0xAAAAAB5E | 
|  | COSB1:	.long 0xBF000000 | 
|  |  | 
|  | INVTWOPI: .long 0x3FFC0000,0xA2F9836E,0x4E44152A | 
|  |  | 
|  | TWOPI1:	.long 0x40010000,0xC90FDAA2,0x00000000,0x00000000 | 
|  | TWOPI2:	.long 0x3FDF0000,0x85A308D4,0x00000000,0x00000000 | 
|  |  | 
|  | |xref	PITBL | 
|  |  | 
|  | .set	INARG,FP_SCR4 | 
|  |  | 
|  | .set	X,FP_SCR5 | 
|  | .set	XDCARE,X+2 | 
|  | .set	XFRAC,X+4 | 
|  |  | 
|  | .set	RPRIME,FP_SCR1 | 
|  | .set	SPRIME,FP_SCR2 | 
|  |  | 
|  | .set	POSNEG1,L_SCR1 | 
|  | .set	TWOTO63,L_SCR1 | 
|  |  | 
|  | .set	ENDFLAG,L_SCR2 | 
|  | .set	N,L_SCR2 | 
|  |  | 
|  | .set	ADJN,L_SCR3 | 
|  |  | 
|  | | xref	t_frcinx | 
|  | |xref	t_extdnrm | 
|  | |xref	sto_cos | 
|  |  | 
|  | .global	ssind | 
|  | ssind: | 
|  | |--SIN(X) = X FOR DENORMALIZED X | 
|  | bra		t_extdnrm | 
|  |  | 
|  | .global	scosd | 
|  | scosd: | 
|  | |--COS(X) = 1 FOR DENORMALIZED X | 
|  |  | 
|  | fmoves		#0x3F800000,%fp0 | 
|  | | | 
|  | |	9D25B Fix: Sometimes the previous fmove.s sets fpsr bits | 
|  | | | 
|  | fmovel		#0,%fpsr | 
|  | | | 
|  | bra		t_frcinx | 
|  |  | 
|  | .global	ssin | 
|  | ssin: | 
|  | |--SET ADJN TO 0 | 
|  | movel		#0,ADJN(%a6) | 
|  | bras		SINBGN | 
|  |  | 
|  | .global	scos | 
|  | scos: | 
|  | |--SET ADJN TO 1 | 
|  | movel		#1,ADJN(%a6) | 
|  |  | 
|  | SINBGN: | 
|  | |--SAVE FPCR, FP1. CHECK IF |X| IS TOO SMALL OR LARGE | 
|  |  | 
|  | fmovex		(%a0),%fp0	| ...LOAD INPUT | 
|  |  | 
|  | movel		(%a0),%d0 | 
|  | movew		4(%a0),%d0 | 
|  | fmovex		%fp0,X(%a6) | 
|  | andil		#0x7FFFFFFF,%d0		| ...COMPACTIFY X | 
|  |  | 
|  | cmpil		#0x3FD78000,%d0		| ...|X| >= 2**(-40)? | 
|  | bges		SOK1 | 
|  | bra		SINSM | 
|  |  | 
|  | SOK1: | 
|  | cmpil		#0x4004BC7E,%d0		| ...|X| < 15 PI? | 
|  | blts		SINMAIN | 
|  | bra		REDUCEX | 
|  |  | 
|  | SINMAIN: | 
|  | |--THIS IS THE USUAL CASE, |X| <= 15 PI. | 
|  | |--THE ARGUMENT REDUCTION IS DONE BY TABLE LOOK UP. | 
|  | fmovex		%fp0,%fp1 | 
|  | fmuld		TWOBYPI,%fp1	| ...X*2/PI | 
|  |  | 
|  | |--HIDE THE NEXT THREE INSTRUCTIONS | 
|  | lea		PITBL+0x200,%a1 | ...TABLE OF N*PI/2, N = -32,...,32 | 
|  |  | 
|  |  | 
|  | |--FP1 IS NOW READY | 
|  | fmovel		%fp1,N(%a6)		| ...CONVERT TO INTEGER | 
|  |  | 
|  | movel		N(%a6),%d0 | 
|  | asll		#4,%d0 | 
|  | addal		%d0,%a1	| ...A1 IS THE ADDRESS OF N*PIBY2 | 
|  | |				...WHICH IS IN TWO PIECES Y1 & Y2 | 
|  |  | 
|  | fsubx		(%a1)+,%fp0	| ...X-Y1 | 
|  | |--HIDE THE NEXT ONE | 
|  | fsubs		(%a1),%fp0	| ...FP0 IS R = (X-Y1)-Y2 | 
|  |  | 
|  | SINCONT: | 
|  | |--continuation from REDUCEX | 
|  |  | 
|  | |--GET N+ADJN AND SEE IF SIN(R) OR COS(R) IS NEEDED | 
|  | movel		N(%a6),%d0 | 
|  | addl		ADJN(%a6),%d0	| ...SEE IF D0 IS ODD OR EVEN | 
|  | rorl		#1,%d0	| ...D0 WAS ODD IFF D0 IS NEGATIVE | 
|  | cmpil		#0,%d0 | 
|  | blt		COSPOLY | 
|  |  | 
|  | SINPOLY: | 
|  | |--LET J BE THE LEAST SIG. BIT OF D0, LET SGN := (-1)**J. | 
|  | |--THEN WE RETURN	SGN*SIN(R). SGN*SIN(R) IS COMPUTED BY | 
|  | |--R' + R'*S*(A1 + S(A2 + S(A3 + S(A4 + ... + SA7)))), WHERE | 
|  | |--R' = SGN*R, S=R*R. THIS CAN BE REWRITTEN AS | 
|  | |--R' + R'*S*( [A1+T(A3+T(A5+TA7))] + [S(A2+T(A4+TA6))]) | 
|  | |--WHERE T=S*S. | 
|  | |--NOTE THAT A3 THROUGH A7 ARE STORED IN DOUBLE PRECISION | 
|  | |--WHILE A1 AND A2 ARE IN DOUBLE-EXTENDED FORMAT. | 
|  | fmovex		%fp0,X(%a6)	| ...X IS R | 
|  | fmulx		%fp0,%fp0	| ...FP0 IS S | 
|  | |---HIDE THE NEXT TWO WHILE WAITING FOR FP0 | 
|  | fmoved		SINA7,%fp3 | 
|  | fmoved		SINA6,%fp2 | 
|  | |--FP0 IS NOW READY | 
|  | fmovex		%fp0,%fp1 | 
|  | fmulx		%fp1,%fp1	| ...FP1 IS T | 
|  | |--HIDE THE NEXT TWO WHILE WAITING FOR FP1 | 
|  |  | 
|  | rorl		#1,%d0 | 
|  | andil		#0x80000000,%d0 | 
|  | |				...LEAST SIG. BIT OF D0 IN SIGN POSITION | 
|  | eorl		%d0,X(%a6)	| ...X IS NOW R'= SGN*R | 
|  |  | 
|  | fmulx		%fp1,%fp3	| ...TA7 | 
|  | fmulx		%fp1,%fp2	| ...TA6 | 
|  |  | 
|  | faddd		SINA5,%fp3 | ...A5+TA7 | 
|  | faddd		SINA4,%fp2 | ...A4+TA6 | 
|  |  | 
|  | fmulx		%fp1,%fp3	| ...T(A5+TA7) | 
|  | fmulx		%fp1,%fp2	| ...T(A4+TA6) | 
|  |  | 
|  | faddd		SINA3,%fp3 | ...A3+T(A5+TA7) | 
|  | faddx		SINA2,%fp2 | ...A2+T(A4+TA6) | 
|  |  | 
|  | fmulx		%fp3,%fp1	| ...T(A3+T(A5+TA7)) | 
|  |  | 
|  | fmulx		%fp0,%fp2	| ...S(A2+T(A4+TA6)) | 
|  | faddx		SINA1,%fp1 | ...A1+T(A3+T(A5+TA7)) | 
|  | fmulx		X(%a6),%fp0	| ...R'*S | 
|  |  | 
|  | faddx		%fp2,%fp1	| ...[A1+T(A3+T(A5+TA7))]+[S(A2+T(A4+TA6))] | 
|  | |--FP3 RELEASED, RESTORE NOW AND TAKE SOME ADVANTAGE OF HIDING | 
|  | |--FP2 RELEASED, RESTORE NOW AND TAKE FULL ADVANTAGE OF HIDING | 
|  |  | 
|  |  | 
|  | fmulx		%fp1,%fp0		| ...SIN(R')-R' | 
|  | |--FP1 RELEASED. | 
|  |  | 
|  | fmovel		%d1,%FPCR		|restore users exceptions | 
|  | faddx		X(%a6),%fp0		|last inst - possible exception set | 
|  | bra		t_frcinx | 
|  |  | 
|  |  | 
|  | COSPOLY: | 
|  | |--LET J BE THE LEAST SIG. BIT OF D0, LET SGN := (-1)**J. | 
|  | |--THEN WE RETURN	SGN*COS(R). SGN*COS(R) IS COMPUTED BY | 
|  | |--SGN + S'*(B1 + S(B2 + S(B3 + S(B4 + ... + SB8)))), WHERE | 
|  | |--S=R*R AND S'=SGN*S. THIS CAN BE REWRITTEN AS | 
|  | |--SGN + S'*([B1+T(B3+T(B5+TB7))] + [S(B2+T(B4+T(B6+TB8)))]) | 
|  | |--WHERE T=S*S. | 
|  | |--NOTE THAT B4 THROUGH B8 ARE STORED IN DOUBLE PRECISION | 
|  | |--WHILE B2 AND B3 ARE IN DOUBLE-EXTENDED FORMAT, B1 IS -1/2 | 
|  | |--AND IS THEREFORE STORED AS SINGLE PRECISION. | 
|  |  | 
|  | fmulx		%fp0,%fp0	| ...FP0 IS S | 
|  | |---HIDE THE NEXT TWO WHILE WAITING FOR FP0 | 
|  | fmoved		COSB8,%fp2 | 
|  | fmoved		COSB7,%fp3 | 
|  | |--FP0 IS NOW READY | 
|  | fmovex		%fp0,%fp1 | 
|  | fmulx		%fp1,%fp1	| ...FP1 IS T | 
|  | |--HIDE THE NEXT TWO WHILE WAITING FOR FP1 | 
|  | fmovex		%fp0,X(%a6)	| ...X IS S | 
|  | rorl		#1,%d0 | 
|  | andil		#0x80000000,%d0 | 
|  | |			...LEAST SIG. BIT OF D0 IN SIGN POSITION | 
|  |  | 
|  | fmulx		%fp1,%fp2	| ...TB8 | 
|  | |--HIDE THE NEXT TWO WHILE WAITING FOR THE XU | 
|  | eorl		%d0,X(%a6)	| ...X IS NOW S'= SGN*S | 
|  | andil		#0x80000000,%d0 | 
|  |  | 
|  | fmulx		%fp1,%fp3	| ...TB7 | 
|  | |--HIDE THE NEXT TWO WHILE WAITING FOR THE XU | 
|  | oril		#0x3F800000,%d0	| ...D0 IS SGN IN SINGLE | 
|  | movel		%d0,POSNEG1(%a6) | 
|  |  | 
|  | faddd		COSB6,%fp2 | ...B6+TB8 | 
|  | faddd		COSB5,%fp3 | ...B5+TB7 | 
|  |  | 
|  | fmulx		%fp1,%fp2	| ...T(B6+TB8) | 
|  | fmulx		%fp1,%fp3	| ...T(B5+TB7) | 
|  |  | 
|  | faddd		COSB4,%fp2 | ...B4+T(B6+TB8) | 
|  | faddx		COSB3,%fp3 | ...B3+T(B5+TB7) | 
|  |  | 
|  | fmulx		%fp1,%fp2	| ...T(B4+T(B6+TB8)) | 
|  | fmulx		%fp3,%fp1	| ...T(B3+T(B5+TB7)) | 
|  |  | 
|  | faddx		COSB2,%fp2 | ...B2+T(B4+T(B6+TB8)) | 
|  | fadds		COSB1,%fp1 | ...B1+T(B3+T(B5+TB7)) | 
|  |  | 
|  | fmulx		%fp2,%fp0	| ...S(B2+T(B4+T(B6+TB8))) | 
|  | |--FP3 RELEASED, RESTORE NOW AND TAKE SOME ADVANTAGE OF HIDING | 
|  | |--FP2 RELEASED. | 
|  |  | 
|  |  | 
|  | faddx		%fp1,%fp0 | 
|  | |--FP1 RELEASED | 
|  |  | 
|  | fmulx		X(%a6),%fp0 | 
|  |  | 
|  | fmovel		%d1,%FPCR		|restore users exceptions | 
|  | fadds		POSNEG1(%a6),%fp0	|last inst - possible exception set | 
|  | bra		t_frcinx | 
|  |  | 
|  |  | 
|  | SINBORS: | 
|  | |--IF |X| > 15PI, WE USE THE GENERAL ARGUMENT REDUCTION. | 
|  | |--IF |X| < 2**(-40), RETURN X OR 1. | 
|  | cmpil		#0x3FFF8000,%d0 | 
|  | bgts		REDUCEX | 
|  |  | 
|  |  | 
|  | SINSM: | 
|  | movel		ADJN(%a6),%d0 | 
|  | cmpil		#0,%d0 | 
|  | bgts		COSTINY | 
|  |  | 
|  | SINTINY: | 
|  | movew		#0x0000,XDCARE(%a6)	| ...JUST IN CASE | 
|  | fmovel		%d1,%FPCR		|restore users exceptions | 
|  | fmovex		X(%a6),%fp0		|last inst - possible exception set | 
|  | bra		t_frcinx | 
|  |  | 
|  |  | 
|  | COSTINY: | 
|  | fmoves		#0x3F800000,%fp0 | 
|  |  | 
|  | fmovel		%d1,%FPCR		|restore users exceptions | 
|  | fsubs		#0x00800000,%fp0	|last inst - possible exception set | 
|  | bra		t_frcinx | 
|  |  | 
|  |  | 
|  | REDUCEX: | 
|  | |--WHEN REDUCEX IS USED, THE CODE WILL INEVITABLY BE SLOW. | 
|  | |--THIS REDUCTION METHOD, HOWEVER, IS MUCH FASTER THAN USING | 
|  | |--THE REMAINDER INSTRUCTION WHICH IS NOW IN SOFTWARE. | 
|  |  | 
|  | fmovemx	%fp2-%fp5,-(%a7)	| ...save FP2 through FP5 | 
|  | movel		%d2,-(%a7) | 
|  | fmoves         #0x00000000,%fp1 | 
|  | |--If compact form of abs(arg) in d0=$7ffeffff, argument is so large that | 
|  | |--there is a danger of unwanted overflow in first LOOP iteration.  In this | 
|  | |--case, reduce argument by one remainder step to make subsequent reduction | 
|  | |--safe. | 
|  | cmpil	#0x7ffeffff,%d0		|is argument dangerously large? | 
|  | bnes	LOOP | 
|  | movel	#0x7ffe0000,FP_SCR2(%a6)	|yes | 
|  | |					;create 2**16383*PI/2 | 
|  | movel	#0xc90fdaa2,FP_SCR2+4(%a6) | 
|  | clrl	FP_SCR2+8(%a6) | 
|  | ftstx	%fp0			|test sign of argument | 
|  | movel	#0x7fdc0000,FP_SCR3(%a6)	|create low half of 2**16383* | 
|  | |					;PI/2 at FP_SCR3 | 
|  | movel	#0x85a308d3,FP_SCR3+4(%a6) | 
|  | clrl   FP_SCR3+8(%a6) | 
|  | fblt	red_neg | 
|  | orw	#0x8000,FP_SCR2(%a6)	|positive arg | 
|  | orw	#0x8000,FP_SCR3(%a6) | 
|  | red_neg: | 
|  | faddx  FP_SCR2(%a6),%fp0		|high part of reduction is exact | 
|  | fmovex  %fp0,%fp1		|save high result in fp1 | 
|  | faddx  FP_SCR3(%a6),%fp0		|low part of reduction | 
|  | fsubx  %fp0,%fp1			|determine low component of result | 
|  | faddx  FP_SCR3(%a6),%fp1		|fp0/fp1 are reduced argument. | 
|  |  | 
|  | |--ON ENTRY, FP0 IS X, ON RETURN, FP0 IS X REM PI/2, |X| <= PI/4. | 
|  | |--integer quotient will be stored in N | 
|  | |--Intermediate remainder is 66-bit long; (R,r) in (FP0,FP1) | 
|  |  | 
|  | LOOP: | 
|  | fmovex		%fp0,INARG(%a6)	| ...+-2**K * F, 1 <= F < 2 | 
|  | movew		INARG(%a6),%d0 | 
|  | movel          %d0,%a1		| ...save a copy of D0 | 
|  | andil		#0x00007FFF,%d0 | 
|  | subil		#0x00003FFF,%d0	| ...D0 IS K | 
|  | cmpil		#28,%d0 | 
|  | bles		LASTLOOP | 
|  | CONTLOOP: | 
|  | subil		#27,%d0	 | ...D0 IS L := K-27 | 
|  | movel		#0,ENDFLAG(%a6) | 
|  | bras		WORK | 
|  | LASTLOOP: | 
|  | clrl		%d0		| ...D0 IS L := 0 | 
|  | movel		#1,ENDFLAG(%a6) | 
|  |  | 
|  | WORK: | 
|  | |--FIND THE REMAINDER OF (R,r) W.R.T.	2**L * (PI/2). L IS SO CHOSEN | 
|  | |--THAT	INT( X * (2/PI) / 2**(L) ) < 2**29. | 
|  |  | 
|  | |--CREATE 2**(-L) * (2/PI), SIGN(INARG)*2**(63), | 
|  | |--2**L * (PIby2_1), 2**L * (PIby2_2) | 
|  |  | 
|  | movel		#0x00003FFE,%d2	| ...BIASED EXPO OF 2/PI | 
|  | subl		%d0,%d2		| ...BIASED EXPO OF 2**(-L)*(2/PI) | 
|  |  | 
|  | movel		#0xA2F9836E,FP_SCR1+4(%a6) | 
|  | movel		#0x4E44152A,FP_SCR1+8(%a6) | 
|  | movew		%d2,FP_SCR1(%a6)	| ...FP_SCR1 is 2**(-L)*(2/PI) | 
|  |  | 
|  | fmovex		%fp0,%fp2 | 
|  | fmulx		FP_SCR1(%a6),%fp2 | 
|  | |--WE MUST NOW FIND INT(FP2). SINCE WE NEED THIS VALUE IN | 
|  | |--FLOATING POINT FORMAT, THE TWO FMOVE'S	FMOVE.L FP <--> N | 
|  | |--WILL BE TOO INEFFICIENT. THE WAY AROUND IT IS THAT | 
|  | |--(SIGN(INARG)*2**63	+	FP2) - SIGN(INARG)*2**63 WILL GIVE | 
|  | |--US THE DESIRED VALUE IN FLOATING POINT. | 
|  |  | 
|  | |--HIDE SIX CYCLES OF INSTRUCTION | 
|  | movel		%a1,%d2 | 
|  | swap		%d2 | 
|  | andil		#0x80000000,%d2 | 
|  | oril		#0x5F000000,%d2	| ...D2 IS SIGN(INARG)*2**63 IN SGL | 
|  | movel		%d2,TWOTO63(%a6) | 
|  |  | 
|  | movel		%d0,%d2 | 
|  | addil		#0x00003FFF,%d2	| ...BIASED EXPO OF 2**L * (PI/2) | 
|  |  | 
|  | |--FP2 IS READY | 
|  | fadds		TWOTO63(%a6),%fp2	| ...THE FRACTIONAL PART OF FP1 IS ROUNDED | 
|  |  | 
|  | |--HIDE 4 CYCLES OF INSTRUCTION; creating 2**(L)*Piby2_1  and  2**(L)*Piby2_2 | 
|  | movew		%d2,FP_SCR2(%a6) | 
|  | clrw           FP_SCR2+2(%a6) | 
|  | movel		#0xC90FDAA2,FP_SCR2+4(%a6) | 
|  | clrl		FP_SCR2+8(%a6)		| ...FP_SCR2 is  2**(L) * Piby2_1 | 
|  |  | 
|  | |--FP2 IS READY | 
|  | fsubs		TWOTO63(%a6),%fp2		| ...FP2 is N | 
|  |  | 
|  | addil		#0x00003FDD,%d0 | 
|  | movew		%d0,FP_SCR3(%a6) | 
|  | clrw           FP_SCR3+2(%a6) | 
|  | movel		#0x85A308D3,FP_SCR3+4(%a6) | 
|  | clrl		FP_SCR3+8(%a6)		| ...FP_SCR3 is 2**(L) * Piby2_2 | 
|  |  | 
|  | movel		ENDFLAG(%a6),%d0 | 
|  |  | 
|  | |--We are now ready to perform (R+r) - N*P1 - N*P2, P1 = 2**(L) * Piby2_1 and | 
|  | |--P2 = 2**(L) * Piby2_2 | 
|  | fmovex		%fp2,%fp4 | 
|  | fmulx		FP_SCR2(%a6),%fp4		| ...W = N*P1 | 
|  | fmovex		%fp2,%fp5 | 
|  | fmulx		FP_SCR3(%a6),%fp5		| ...w = N*P2 | 
|  | fmovex		%fp4,%fp3 | 
|  | |--we want P+p = W+w  but  |p| <= half ulp of P | 
|  | |--Then, we need to compute  A := R-P   and  a := r-p | 
|  | faddx		%fp5,%fp3			| ...FP3 is P | 
|  | fsubx		%fp3,%fp4			| ...W-P | 
|  |  | 
|  | fsubx		%fp3,%fp0			| ...FP0 is A := R - P | 
|  | faddx		%fp5,%fp4			| ...FP4 is p = (W-P)+w | 
|  |  | 
|  | fmovex		%fp0,%fp3			| ...FP3 A | 
|  | fsubx		%fp4,%fp1			| ...FP1 is a := r - p | 
|  |  | 
|  | |--Now we need to normalize (A,a) to  "new (R,r)" where R+r = A+a but | 
|  | |--|r| <= half ulp of R. | 
|  | faddx		%fp1,%fp0			| ...FP0 is R := A+a | 
|  | |--No need to calculate r if this is the last loop | 
|  | cmpil		#0,%d0 | 
|  | bgt		RESTORE | 
|  |  | 
|  | |--Need to calculate r | 
|  | fsubx		%fp0,%fp3			| ...A-R | 
|  | faddx		%fp3,%fp1			| ...FP1 is r := (A-R)+a | 
|  | bra		LOOP | 
|  |  | 
|  | RESTORE: | 
|  | fmovel		%fp2,N(%a6) | 
|  | movel		(%a7)+,%d2 | 
|  | fmovemx	(%a7)+,%fp2-%fp5 | 
|  |  | 
|  |  | 
|  | movel		ADJN(%a6),%d0 | 
|  | cmpil		#4,%d0 | 
|  |  | 
|  | blt		SINCONT | 
|  | bras		SCCONT | 
|  |  | 
|  | .global	ssincosd | 
|  | ssincosd: | 
|  | |--SIN AND COS OF X FOR DENORMALIZED X | 
|  |  | 
|  | fmoves		#0x3F800000,%fp1 | 
|  | bsr		sto_cos		|store cosine result | 
|  | bra		t_extdnrm | 
|  |  | 
|  | .global	ssincos | 
|  | ssincos: | 
|  | |--SET ADJN TO 4 | 
|  | movel		#4,ADJN(%a6) | 
|  |  | 
|  | fmovex		(%a0),%fp0	| ...LOAD INPUT | 
|  |  | 
|  | movel		(%a0),%d0 | 
|  | movew		4(%a0),%d0 | 
|  | fmovex		%fp0,X(%a6) | 
|  | andil		#0x7FFFFFFF,%d0		| ...COMPACTIFY X | 
|  |  | 
|  | cmpil		#0x3FD78000,%d0		| ...|X| >= 2**(-40)? | 
|  | bges		SCOK1 | 
|  | bra		SCSM | 
|  |  | 
|  | SCOK1: | 
|  | cmpil		#0x4004BC7E,%d0		| ...|X| < 15 PI? | 
|  | blts		SCMAIN | 
|  | bra		REDUCEX | 
|  |  | 
|  |  | 
|  | SCMAIN: | 
|  | |--THIS IS THE USUAL CASE, |X| <= 15 PI. | 
|  | |--THE ARGUMENT REDUCTION IS DONE BY TABLE LOOK UP. | 
|  | fmovex		%fp0,%fp1 | 
|  | fmuld		TWOBYPI,%fp1	| ...X*2/PI | 
|  |  | 
|  | |--HIDE THE NEXT THREE INSTRUCTIONS | 
|  | lea		PITBL+0x200,%a1 | ...TABLE OF N*PI/2, N = -32,...,32 | 
|  |  | 
|  |  | 
|  | |--FP1 IS NOW READY | 
|  | fmovel		%fp1,N(%a6)		| ...CONVERT TO INTEGER | 
|  |  | 
|  | movel		N(%a6),%d0 | 
|  | asll		#4,%d0 | 
|  | addal		%d0,%a1		| ...ADDRESS OF N*PIBY2, IN Y1, Y2 | 
|  |  | 
|  | fsubx		(%a1)+,%fp0	| ...X-Y1 | 
|  | fsubs		(%a1),%fp0	| ...FP0 IS R = (X-Y1)-Y2 | 
|  |  | 
|  | SCCONT: | 
|  | |--continuation point from REDUCEX | 
|  |  | 
|  | |--HIDE THE NEXT TWO | 
|  | movel		N(%a6),%d0 | 
|  | rorl		#1,%d0 | 
|  |  | 
|  | cmpil		#0,%d0		| ...D0 < 0 IFF N IS ODD | 
|  | bge		NEVEN | 
|  |  | 
|  | NODD: | 
|  | |--REGISTERS SAVED SO FAR: D0, A0, FP2. | 
|  |  | 
|  | fmovex		%fp0,RPRIME(%a6) | 
|  | fmulx		%fp0,%fp0	 | ...FP0 IS S = R*R | 
|  | fmoved		SINA7,%fp1	| ...A7 | 
|  | fmoved		COSB8,%fp2	| ...B8 | 
|  | fmulx		%fp0,%fp1	 | ...SA7 | 
|  | movel		%d2,-(%a7) | 
|  | movel		%d0,%d2 | 
|  | fmulx		%fp0,%fp2	 | ...SB8 | 
|  | rorl		#1,%d2 | 
|  | andil		#0x80000000,%d2 | 
|  |  | 
|  | faddd		SINA6,%fp1	| ...A6+SA7 | 
|  | eorl		%d0,%d2 | 
|  | andil		#0x80000000,%d2 | 
|  | faddd		COSB7,%fp2	| ...B7+SB8 | 
|  |  | 
|  | fmulx		%fp0,%fp1	 | ...S(A6+SA7) | 
|  | eorl		%d2,RPRIME(%a6) | 
|  | movel		(%a7)+,%d2 | 
|  | fmulx		%fp0,%fp2	 | ...S(B7+SB8) | 
|  | rorl		#1,%d0 | 
|  | andil		#0x80000000,%d0 | 
|  |  | 
|  | faddd		SINA5,%fp1	| ...A5+S(A6+SA7) | 
|  | movel		#0x3F800000,POSNEG1(%a6) | 
|  | eorl		%d0,POSNEG1(%a6) | 
|  | faddd		COSB6,%fp2	| ...B6+S(B7+SB8) | 
|  |  | 
|  | fmulx		%fp0,%fp1	 | ...S(A5+S(A6+SA7)) | 
|  | fmulx		%fp0,%fp2	 | ...S(B6+S(B7+SB8)) | 
|  | fmovex		%fp0,SPRIME(%a6) | 
|  |  | 
|  | faddd		SINA4,%fp1	| ...A4+S(A5+S(A6+SA7)) | 
|  | eorl		%d0,SPRIME(%a6) | 
|  | faddd		COSB5,%fp2	| ...B5+S(B6+S(B7+SB8)) | 
|  |  | 
|  | fmulx		%fp0,%fp1	 | ...S(A4+...) | 
|  | fmulx		%fp0,%fp2	 | ...S(B5+...) | 
|  |  | 
|  | faddd		SINA3,%fp1	| ...A3+S(A4+...) | 
|  | faddd		COSB4,%fp2	| ...B4+S(B5+...) | 
|  |  | 
|  | fmulx		%fp0,%fp1	 | ...S(A3+...) | 
|  | fmulx		%fp0,%fp2	 | ...S(B4+...) | 
|  |  | 
|  | faddx		SINA2,%fp1	| ...A2+S(A3+...) | 
|  | faddx		COSB3,%fp2	| ...B3+S(B4+...) | 
|  |  | 
|  | fmulx		%fp0,%fp1	 | ...S(A2+...) | 
|  | fmulx		%fp0,%fp2	 | ...S(B3+...) | 
|  |  | 
|  | faddx		SINA1,%fp1	| ...A1+S(A2+...) | 
|  | faddx		COSB2,%fp2	| ...B2+S(B3+...) | 
|  |  | 
|  | fmulx		%fp0,%fp1	 | ...S(A1+...) | 
|  | fmulx		%fp2,%fp0	 | ...S(B2+...) | 
|  |  | 
|  |  | 
|  |  | 
|  | fmulx		RPRIME(%a6),%fp1	| ...R'S(A1+...) | 
|  | fadds		COSB1,%fp0	| ...B1+S(B2...) | 
|  | fmulx		SPRIME(%a6),%fp0	| ...S'(B1+S(B2+...)) | 
|  |  | 
|  | movel		%d1,-(%sp)	|restore users mode & precision | 
|  | andil		#0xff,%d1		|mask off all exceptions | 
|  | fmovel		%d1,%FPCR | 
|  | faddx		RPRIME(%a6),%fp1	| ...COS(X) | 
|  | bsr		sto_cos		|store cosine result | 
|  | fmovel		(%sp)+,%FPCR	|restore users exceptions | 
|  | fadds		POSNEG1(%a6),%fp0	| ...SIN(X) | 
|  |  | 
|  | bra		t_frcinx | 
|  |  | 
|  |  | 
|  | NEVEN: | 
|  | |--REGISTERS SAVED SO FAR: FP2. | 
|  |  | 
|  | fmovex		%fp0,RPRIME(%a6) | 
|  | fmulx		%fp0,%fp0	 | ...FP0 IS S = R*R | 
|  | fmoved		COSB8,%fp1			| ...B8 | 
|  | fmoved		SINA7,%fp2			| ...A7 | 
|  | fmulx		%fp0,%fp1	 | ...SB8 | 
|  | fmovex		%fp0,SPRIME(%a6) | 
|  | fmulx		%fp0,%fp2	 | ...SA7 | 
|  | rorl		#1,%d0 | 
|  | andil		#0x80000000,%d0 | 
|  | faddd		COSB7,%fp1	| ...B7+SB8 | 
|  | faddd		SINA6,%fp2	| ...A6+SA7 | 
|  | eorl		%d0,RPRIME(%a6) | 
|  | eorl		%d0,SPRIME(%a6) | 
|  | fmulx		%fp0,%fp1	 | ...S(B7+SB8) | 
|  | oril		#0x3F800000,%d0 | 
|  | movel		%d0,POSNEG1(%a6) | 
|  | fmulx		%fp0,%fp2	 | ...S(A6+SA7) | 
|  |  | 
|  | faddd		COSB6,%fp1	| ...B6+S(B7+SB8) | 
|  | faddd		SINA5,%fp2	| ...A5+S(A6+SA7) | 
|  |  | 
|  | fmulx		%fp0,%fp1	 | ...S(B6+S(B7+SB8)) | 
|  | fmulx		%fp0,%fp2	 | ...S(A5+S(A6+SA7)) | 
|  |  | 
|  | faddd		COSB5,%fp1	| ...B5+S(B6+S(B7+SB8)) | 
|  | faddd		SINA4,%fp2	| ...A4+S(A5+S(A6+SA7)) | 
|  |  | 
|  | fmulx		%fp0,%fp1	 | ...S(B5+...) | 
|  | fmulx		%fp0,%fp2	 | ...S(A4+...) | 
|  |  | 
|  | faddd		COSB4,%fp1	| ...B4+S(B5+...) | 
|  | faddd		SINA3,%fp2	| ...A3+S(A4+...) | 
|  |  | 
|  | fmulx		%fp0,%fp1	 | ...S(B4+...) | 
|  | fmulx		%fp0,%fp2	 | ...S(A3+...) | 
|  |  | 
|  | faddx		COSB3,%fp1	| ...B3+S(B4+...) | 
|  | faddx		SINA2,%fp2	| ...A2+S(A3+...) | 
|  |  | 
|  | fmulx		%fp0,%fp1	 | ...S(B3+...) | 
|  | fmulx		%fp0,%fp2	 | ...S(A2+...) | 
|  |  | 
|  | faddx		COSB2,%fp1	| ...B2+S(B3+...) | 
|  | faddx		SINA1,%fp2	| ...A1+S(A2+...) | 
|  |  | 
|  | fmulx		%fp0,%fp1	 | ...S(B2+...) | 
|  | fmulx		%fp2,%fp0	 | ...s(a1+...) | 
|  |  | 
|  |  | 
|  |  | 
|  | fadds		COSB1,%fp1	| ...B1+S(B2...) | 
|  | fmulx		RPRIME(%a6),%fp0	| ...R'S(A1+...) | 
|  | fmulx		SPRIME(%a6),%fp1	| ...S'(B1+S(B2+...)) | 
|  |  | 
|  | movel		%d1,-(%sp)	|save users mode & precision | 
|  | andil		#0xff,%d1		|mask off all exceptions | 
|  | fmovel		%d1,%FPCR | 
|  | fadds		POSNEG1(%a6),%fp1	| ...COS(X) | 
|  | bsr		sto_cos		|store cosine result | 
|  | fmovel		(%sp)+,%FPCR	|restore users exceptions | 
|  | faddx		RPRIME(%a6),%fp0	| ...SIN(X) | 
|  |  | 
|  | bra		t_frcinx | 
|  |  | 
|  | SCBORS: | 
|  | cmpil		#0x3FFF8000,%d0 | 
|  | bgt		REDUCEX | 
|  |  | 
|  |  | 
|  | SCSM: | 
|  | movew		#0x0000,XDCARE(%a6) | 
|  | fmoves		#0x3F800000,%fp1 | 
|  |  | 
|  | movel		%d1,-(%sp)	|save users mode & precision | 
|  | andil		#0xff,%d1		|mask off all exceptions | 
|  | fmovel		%d1,%FPCR | 
|  | fsubs		#0x00800000,%fp1 | 
|  | bsr		sto_cos		|store cosine result | 
|  | fmovel		(%sp)+,%FPCR	|restore users exceptions | 
|  | fmovex		X(%a6),%fp0 | 
|  | bra		t_frcinx | 
|  |  | 
|  | |end |