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Based on kernel version 3.15.4. Page generated on 2014-07-07 08:59 EST.

1	This directory contains the version 0.92 test release of the NetWinder 
2	Floating Point Emulator.
3	
4	The majority of the code was written by me, Scott Bambrough It is
5	written in C, with a small number of routines in inline assembler
6	where required.  It was written quickly, with a goal of implementing a
7	working version of all the floating point instructions the compiler
8	emits as the first target.  I have attempted to be as optimal as
9	possible, but there remains much room for improvement.
10	
11	I have attempted to make the emulator as portable as possible.  One of
12	the problems is with leading underscores on kernel symbols.  Elf
13	kernels have no leading underscores, a.out compiled kernels do.  I
14	have attempted to use the C_SYMBOL_NAME macro wherever this may be
15	important.
16	
17	Another choice I made was in the file structure.  I have attempted to
18	contain all operating system specific code in one module (fpmodule.*).
19	All the other files contain emulator specific code.  This should allow
20	others to port the emulator to NetBSD for instance relatively easily.
21	
22	The floating point operations are based on SoftFloat Release 2, by
23	John Hauser.  SoftFloat is a software implementation of floating-point
24	that conforms to the IEC/IEEE Standard for Binary Floating-point
25	Arithmetic.  As many as four formats are supported: single precision,
26	double precision, extended double precision, and quadruple precision.
27	All operations required by the standard are implemented, except for
28	conversions to and from decimal.  We use only the single precision,
29	double precision and extended double precision formats.  The port of
30	SoftFloat to the ARM was done by Phil Blundell, based on an earlier
31	port of SoftFloat version 1 by Neil Carson for NetBSD/arm32.
32	
33	The file README.FPE contains a description of what has been implemented
34	so far in the emulator.  The file TODO contains a information on what 
35	remains to be done, and other ideas for the emulator.
36	
37	Bug reports, comments, suggestions should be directed to me at
38	<scottb@netwinder.org>.  General reports of "this program doesn't
39	work correctly when your emulator is installed" are useful for
40	determining that bugs still exist; but are virtually useless when
41	attempting to isolate the problem.  Please report them, but don't
42	expect quick action.  Bugs still exist.  The problem remains in isolating
43	which instruction contains the bug.  Small programs illustrating a specific
44	problem are a godsend.
45	
46	Legal Notices
47	-------------
48	
49	The NetWinder Floating Point Emulator is free software.  Everything Rebel.com
50	has written is provided under the GNU GPL.  See the file COPYING for copying
51	conditions.  Excluded from the above is the SoftFloat code.  John Hauser's 
52	legal notice for SoftFloat is included below.
53	
54	-------------------------------------------------------------------------------
55	SoftFloat Legal Notice
56	
57	SoftFloat was written by John R. Hauser.  This work was made possible in
58	part by the International Computer Science Institute, located at Suite 600,
59	1947 Center Street, Berkeley, California 94704.  Funding was partially
60	provided by the National Science Foundation under grant MIP-9311980.  The
61	original version of this code was written as part of a project to build
62	a fixed-point vector processor in collaboration with the University of
63	California at Berkeley, overseen by Profs. Nelson Morgan and John Wawrzynek.
64	
65	THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE.  Although reasonable effort
66	has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT
67	TIMES RESULT IN INCORRECT BEHAVIOR.  USE OF THIS SOFTWARE IS RESTRICTED TO
68	PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY
69	AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE.
70	-------------------------------------------------------------------------------
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