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1da177e4c   Linus Torvalds   Linux-2.6.12-rc2 
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  |
  |	scosh.sa 3.1 12/10/90
  |
  |	The entry point sCosh computes the hyperbolic cosine of
  |	an input argument; sCoshd does the same except for denormalized
  |	input.
  |
  |	Input: Double-extended number X in location pointed to
  |		by address register a0.
  |
  |	Output: The value cosh(X) returned in floating-point register Fp0.
  |
  |	Accuracy and Monotonicity: The returned result is within 3 ulps 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 program sCOSH takes approximately 250 cycles.
  |
  |	Algorithm:
  |
  |	COSH
  |	1. If |X| > 16380 log2, go to 3.
  |
  |	2. (|X| <= 16380 log2) Cosh(X) is obtained by the formulae
  |		y = |X|, z = exp(Y), and
  |		cosh(X) = (1/2)*( z + 1/z ).
  |		Exit.
  |
  |	3. (|X| > 16380 log2). If |X| > 16480 log2, go to 5.
  |
  |	4. (16380 log2 < |X| <= 16480 log2)
  |		cosh(X) = sign(X) * exp(|X|)/2.
  |		However, invoking exp(|X|) may cause premature overflow.
  |		Thus, we calculate sinh(X) as follows:
  |		Y	:= |X|
  |		Fact	:=	2**(16380)
  |		Y'	:= Y - 16381 log2
  |		cosh(X) := Fact * exp(Y').
  |		Exit.
  |
  |	5. (|X| > 16480 log2) sinh(X) must overflow. Return
  |		Huge*Huge to generate overflow and an infinity with
  |		the appropriate sign. Huge is the largest finite number in
  |		extended format. Exit.
  |
  |
  
  |		Copyright (C) Motorola, Inc. 1990
  |			All Rights Reserved
  |
e00d82d07   Matt Waddel   [PATCH] Add wordi... 
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  |       For details on the license for this file, please see the
  |       file, README, in this same directory.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2 
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  |SCOSH	idnt	2,1 | Motorola 040 Floating Point Software Package
  
  	|section	8
  
  	|xref	t_ovfl
  	|xref	t_frcinx
  	|xref	setox
  
  T1:	.long 0x40C62D38,0xD3D64634 | ... 16381 LOG2 LEAD
  T2:	.long 0x3D6F90AE,0xB1E75CC7 | ... 16381 LOG2 TRAIL
  
  TWO16380: .long 0x7FFB0000,0x80000000,0x00000000,0x00000000
  
  	.global	scoshd
  scoshd:
  |--COSH(X) = 1 FOR DENORMALIZED X
  
  	fmoves		#0x3F800000,%fp0
  
  	fmovel		%d1,%FPCR
  	fadds		#0x00800000,%fp0
  	bra		t_frcinx
  
  	.global	scosh
  scosh:
  	fmovex		(%a0),%fp0	| ...LOAD INPUT
  
  	movel		(%a0),%d0
  	movew		4(%a0),%d0
  	andil		#0x7FFFFFFF,%d0
  	cmpil		#0x400CB167,%d0
  	bgts		COSHBIG
  
  |--THIS IS THE USUAL CASE, |X| < 16380 LOG2
  |--COSH(X) = (1/2) * ( EXP(X) + 1/EXP(X) )
  
  	fabsx		%fp0		| ...|X|
  
  	movel		%d1,-(%sp)
  	clrl		%d1
  	fmovemx	%fp0-%fp0,(%a0)	|pass parameter to setox
  	bsr		setox		| ...FP0 IS EXP(|X|)
  	fmuls		#0x3F000000,%fp0	| ...(1/2)EXP(|X|)
  	movel		(%sp)+,%d1
  
  	fmoves		#0x3E800000,%fp1	| ...(1/4)
  	fdivx		%fp0,%fp1		| ...1/(2 EXP(|X|))
  
  	fmovel		%d1,%FPCR
  	faddx		%fp1,%fp0
  
  	bra		t_frcinx
  
  COSHBIG:
  	cmpil		#0x400CB2B3,%d0
  	bgts		COSHHUGE
  
  	fabsx		%fp0
  	fsubd		T1(%pc),%fp0		| ...(|X|-16381LOG2_LEAD)
  	fsubd		T2(%pc),%fp0		| ...|X| - 16381 LOG2, ACCURATE
  
  	movel		%d1,-(%sp)
  	clrl		%d1
  	fmovemx	%fp0-%fp0,(%a0)
  	bsr		setox
  	fmovel		(%sp)+,%fpcr
  
  	fmulx		TWO16380(%pc),%fp0
  	bra		t_frcinx
  
  COSHHUGE:
  	fmovel		#0,%fpsr		|clr N bit if set by source
  	bclrb		#7,(%a0)		|always return positive value
  	fmovemx	(%a0),%fp0-%fp0
  	bra		t_ovfl
  
  	|end