Commit Graph

20 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
Ralf Baechle fb738f8544 MIPS: math-emu: Reduce code duplication.
The fix in the preceeding commit did do exactly the same thing in two
places showing some code cleanup was due.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-06-26 10:47:55 +01:00
Ralf Baechle 91496ea9f8 MIPS: math-emu: Work around limitations of older GCC.
Older GCC doesn't get named initializations of anonymous structs right,
that is members are not initializable in the containing structure through
name however old style initializations are working fine.

The issue exists with gcc up to 4.5.x.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-06-16 12:47:47 +01:00
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 49548b09e0 MIPS: math-emu: Cleanup definition of structs describe sp/dp floats.
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 1eaf198d3a MIPS: math-emu: Cleanup stdarg usage including apparently bogus comment.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-23 15:11:12 +02:00
Ralf Baechle 08a07904e1 MIPS: math-emu: Remove most ifdefery.
Most of these tests should be runtime tests.  This also finally means
that on a MIPS III systems MIPS IV opcodes are going to result in an
exception as they're supposed to.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-21 11:12:58 +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 2370881821 MIPS: math-emu: Use English spelling of `constant' rather than Danish.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-21 11:12:48 +02:00
Ralf Baechle cae55066cb MIPS: math-emu: Mark exception handling functions as __cold.
Optimizes the code flow and shaves of half a percent of the math-emu
code size.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-21 11:12:47 +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
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
Richard Knutsson 8142294dda [MIPS] Compliment va_start() with va_end().
Signed-off-by: Richard Knutsson <ricknu-0@student.ltu.se>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-11-26 17:26:15 +00:00
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
Ralf Baechle 3c5c8f6748 Delete unused ieee754_cname[] and declaration.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-10-29 19:32:52 +01:00
Ralf Baechle efec3c4e96 Include for prototypes.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-10-29 19:32:51 +01:00
Ralf Baechle cd21dfcfbb Fix preemption and SMP problems in the FP emulator code.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-10-29 19:31:12 +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