Commit Graph

15 Commits

Author SHA1 Message Date
Maciej W. Rozycki 90d53a91fb MIPS: math-emu: Add IEEE Std 754-2008 NaN encoding emulation
Implement IEEE Std 754-2008 NaN encoding wired to the state of the
FCSR.NAN2008 bit.  Make the interpretation of the quiet bit in NaN data
as follows:

* in the legacy mode originally defined by the MIPS architecture the
  value of 1 denotes an sNaN whereas the value of 0 denotes a qNaN,

* in the 2008 mode introduced with revision 5 of the MIPS architecture
  the value of 0 denotes an sNaN whereas the value of 1 denotes a qNaN,
  following the definition of the preferred NaN encoding introduced with
  IEEE Std 754-2008.

In the 2008 mode, following the requirement of the said standard, quiet
an sNaN where needed by setting the quiet bit to 1 and leaving all the
NaN payload bits unchanged.

Update format conversion operations according to the rules set by IEEE
Std 754-2008 and the MIPS architecture.  Specifically:

* propagate NaN payload bits through conversions between floating-point
  formats such that as much information as possible is preserved and
  specifically a conversion from a narrower format to a wider format and
  then back to the original format does not change a qNaN payload in any
  way,

* conversions from a floating-point to an integer format where the
  source is a NaN, infinity or a value that would convert to an integer
  outside the range of the result format produce, under the default
  exception handling, the respective values defined by the MIPS
  architecture.

In full FPU emulation set the FIR.HAS2008 bit to 1, however do not make
any further FCSR bits writable.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11477/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-20 00:39:20 +01:00
Markos Chandras 166457436e MIPS: math-emu: Fix indentation
Fix indentation for the final 'else' blocks.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10735/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-09-03 12:07:42 +02:00
Maciej W. Rozycki c9a1084516 MIPS: math-emu: Optimise NaN handling in comparisons
We have the input operands already classified in `ieee754sp_cmp' and
`ieee754dp_cmp' comparison operations, so use the class obtained to tell
NaNs and numbers apart rather than classifying inputs again for this
purpose, reducing the size of code by 24 and 40 instructions or 96 and
160 bytes respectively.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9689/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-08 01:09:35 +02:00
Ralf Baechle 3f7cac416b MIPS: math-emu: Cleanup coding style.
o Only define variables in the outermost block
 o One empty line at most
 o Format comments as per CodingStyle
 o Update FSF address in licensing term comment
 o Spell FPU and MIPS in all capitals.
 o Remove ####-type of lines in comments.
 o Try to make things a bit most consistent between sp_*.c / dp_*.c files.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-23 15:11:15 +02:00
Ralf Baechle 90efba36ed MIPS: math-emu: Get rid of the useless parts of exception handling.
All it really did was throw a printk for no obvious reason.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-23 15:11:14 +02:00
Ralf Baechle b3a7ad2b0c MIPS: math-emu: Eleminate duplicate definitions of identical macros.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-23 15:11:13 +02:00
Ralf Baechle ad8fb5537a MIPS: math-emu: Replace DP_MBITS with DP_FBITS and SP_MBITS with SP_FBITS.
Both were defined as 23 rsp. 52 though the mentissa is actually a bit more
than the fraction.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-23 15:11:13 +02:00
Ralf Baechle 9e8bad1f9c MIPS: math-emu: Turn macros into functions where possible.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-21 11:12:57 +02:00
Ralf Baechle bee1653593 MIPS: math-emu: Harden ieee754int.h against multiple inclusion.
The header file had no include guards; this only happened to work because
the file only contains macro definitions and protypes.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-21 11:12:56 +02:00
Ralf Baechle 47fa0c0251 MIPS: math-emu: Reformat code according to coding style.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-21 11:12:56 +02:00
Ralf Baechle 7034228792 MIPS: Whitespace cleanup.
Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-02-01 10:00:22 +01:00
David Daney 91b51f3008 MIPS: Fix GCC-4.6 'set but not used' warning in ieee754int.h
GCC-4.6 can find more unused code than previous versions could.

In the case of arch/mips/math-emu/ieee754int.h, the COMPXSP and
COMPXDP macros are used in several places, but a couple of them leave
xs unused.  The easiest thing to do is mark it as __maybe_unused to
quiet the warning.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2032/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-03-14 21:07:26 +01:00
Justin P. Mattock 50a23e6eec Update broken web addresses in arch directory.
The patch below updates broken web addresses in the arch directory.

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Reviewed-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-10-18 11:03:21 +02:00
Ralf Baechle 21a151d8ca [MIPS] checkfiles: Fix "need space after that ','" errors.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-11 23:46:15 +01:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00