code/float-trap.lisp::
  * In the default case, check FOP to see if it's defined.  This means
    it's a divide exception.

 code/x86-vm.lisp::
  * Also check to see if the offending instruction is a DIV or IDIV,
    which means we got an integer overflow.  Return the appropriate
    values in this case.

prevents the exception from being resignaled immediately.

src/code/float-trap.lisp:
o Clear current and accrued exception bits that match any new enabled
  exceptions specified by :traps.

src/general-info/release-20d.txt:
o Update.

not running on solaris/x86.

the occasional problem about SIGFPE's with no exceptions enabled.

error.lisp:
o Add floating-point-denormal-operand arithmetic error.

exports.lisp:
o Export the new arithmetic error type.

float-trap.lisp:
o Check the denormal trap bit and signal the appropriate error.

release-20c.txt:
o Update.

entries with just the file path, removing the revision number, date,
author and state.  The actual information is now computed during
compilation and stored in the fasl itself.  (See ticket:48.)

Solaris/x86.  There should be no functional changes for either other
x86 ports or for the sparc port.

may get confused with source locations if the reader macros are
installed.

boot-2010-02-1 as the bootstrap file.  You should probably also use
the new -P option for build.sh to generate and update the po files
while building.

instead of 53 bits.  This causes the incorrect result (found by Paul):

(ffloor 1.1605184953130993d26 12622780800d0) ->

9.193841782573768d15
-8.05306368d8

The correct result should have a remainder of zero.

Force the precision to be 53 bits (double-float).

Use bootstrap-2009-01-1.lisp to bootstrap this change.

code/float-trap.lisp:
o FLOATING-POINT-MODES for :X87 needs to massage the results into the
  expected format (SSE2 MXCSR order).
o Update for changed VOP names too.

compiler/x86/float.lisp:
o Rename the floating-point-modes and set-floating-point-modes VOPS to
  x87-floating-point-modes and set-x87-floating-point-modes.  Change
  the translations accordingly too.

compiler/x86/parms.lisp:
o The float property bytes have been updated to match the SSE2 MXCSR
  register for both SSE2 and X87 builds because the code assumes SSE2
  format.

lisp/Linux-os.c:
o Don't OR in the SSE2 modes if we're not running an SSE2 build.
  Doing this can erroneously mask out exceptions because the Lisp code
  didn't set up the sse2 modes.  (This happens if you select the x87
  core on a chip that supports sse2.)

lisp/globals.h:
o Declare fpu_mode.

lisp/lisp.c:
o Set fpu_mode to be the mode determined from the core file.  Needed
  in Linux-os.c to process the SSE2 modes correctly with an x87 core
  on a sse2-capable chip.

sse2-packed-2008-11-12).

code.  Rather than introduce a new FreeBSD case to the x86 sigcontext
member accessor routines, collapse all of the system specific routines
down to a common set of routines.

* code/debug-int.lisp - Disable some Darwin-specific code to debug
  NULL mcontext pointers.

* code/float-trap.lisp - Remove ancient FreeBSD-specific code for
  handling floating point signals.

* code/macros.lisp, code/sap.lisp, compiler/saptran.lisp - Include the
  SAP-REF-LONG setter by default on the x86.

* code/x86-vm.lisp - Remove operating system specific sigcontext
  definitions and sigcontext accessors.  Define the alien sigcontext
  as a system area pointer.  Replace the sigcontext accessors with
  foreign function calls that mask the complexity of the underlying
  sigcontext member access.

* compiler/x86/float.lisp - Unconditionally define STORE-LONG-FLOAT.
  This function is used by the %SET-SAP-REF-LONG VOP that underlies
  the SAP-REF-LONG setter....

  the precision control will always be set to double precision.  For
  the duration of calls into C, the precision control will be set to
  the ABI default.  On Linux and Darwin this is double extended
  precision.  On all other platforms the precision control is left as
  double precision.  The specious FLOAT-ACCURACY declaration has been
  eliminated.

* Shorten the precision control field to 24-bits by disposing of the
  unexamined high order eight bits of the status word.  This compacts
  the code generated around floating point mode changes and reduces
  consing.

* Eliminate unnecessary uses of FLDENV and FSTENV.  We can substitute a
  use of FSTENV with FSTSW in FLOATING-POINT-MODES.  This reduces the
  number of cycles to access the relevant mode bits by a factor of
  thirty.  We cannot eliminate FLDENV in SET-FLOATING-POINT-MODES, but
  the common case does not require an update to the status word.  A
  fast path has been added to the VOP that improves the execution time
  by at least a factor of fifteen.

* Remove the precision control option to SET-FLOATING-POINT-MODES.  It
  is the responsibility of the compiler to generating code that yields
  correctly rounded results in double and single precision.

o Need to clear out the individual invalid operation bits when
  clearing the invalid exception bit.

code/exports.lisp:
compiler/ppc/parms.lisp:
o Export FLOAT-INVALID-OP-1-BYTE.  (Needs a better name.)

o Pass the modes to GET-FP-OPERANDS

compiler/ppc/float.lisp:
o If the destination register is the same as one of the source
  registers, an overflow or underflow exception will have replaced the
  source register with the result.  In that case, replace the source
  value with NIL to indicate we don't know.  (We could recompute the
  source from the result, but there would be a round-off error.)

code/float-trap.lisp:
o Set FP modes now.
o Clear out sticky bits in SIGFPE handler

code/ppc-vm.lisp:
o Add (setf sigcontext-floating-point-modes) to set the FP mode.

compiler/ppc/parms.lisp:
o Add fields for various invalid operations bits.
o Fix float-fast-bit

Besides support for Darwin foreign loading, and updates to the ppc-vm
and bsd-os files, this commit removes unix:unix-errno as a foreign variable
and replaces it with a function named unix-errno, and a (setf unix-errno).
This makes both glibc support cleaner, and enables ports like PPC/Darwin
(and the upcoming win32 port) which have no easy way of accessing errno as
a foreign variable able to support this functionality at all.

The current implementation of this is rather make-shift, it would likely
be much cleaner to go the SBCL way and mediate all access to errno via
defined functions in the C runtime.

As an interim feature, the frobbing of the float-trap-modes is currently
commented out for Darwin because of ongoing breakage.

 - add ignore declaration
 - fix endpwent alien routine for Solaris

	* src/code/float-trap.lisp (FPE_*) [freebsd4]: Define constants
	from machine/trap.h.
	(sigfpe-handler) [freebsd4]: Use the code parameter to determine
	the reason for the signal.

	package COMMON-LISP which LISP uses, so that COMMON-LISP no longer
	has the non-ANSI nickname LISP.

	To bootstrap, use boot13.lisp as target:bootstrap.lisp with pmai's
	build scripts, and do a full compile.

	* src/bootfiles/18e/boot13.lisp: Change for all the package
	changes.

	* src/code/exports.lisp: New package common-lisp,
	which lisp uses.

	* src/tools/worldload.lisp:
	* src/tools/setup.lisp: Use cl-user instead of user.
	Use lisp:: instead of cl::.

	* src/tools/worldcom.lisp:
	* src/tools/snapshot-update.lisp:
	* src/tools/pclcom.lisp:
	* src/tools/mk-lisp:
	* src/tools/hemcom.lisp:
	* src/tools/config.lisp:
	* src/tools/comcom.lisp:
	* src/tools/clxcom.lisp:
	* src/tools/clmcom.lisp:
	* src/pcl/defsys.lisp:
	* src/motif/lisp/initial.lisp:
	* src/interface/initial.lisp:
	* src/hemlock/lispmode.lisp (setup-lisp-mode):
	Use cl-user instead of user.

	* src/code/save.lisp (assert-user-package):
	* src/code/print.lisp (%with-standard-...

operation and operands that signalled the floating-point exception so
we can report it.

precision for x86 floating-point operations.

code which were previously conditionalized on :FreeBSD, are now
conditionalized on :BSD instead, with the :BSD feature now implying a
4.4BSD(lite2) derived OS.  This should make future BSD-ports easier.
FreeBSD and OpenBSD are differentiated by having either :FreeBSD or
:OpenBSD on the features list.

Currently the OpenBSD port does not have working ELF support, because
OpenBSD 2.9 is still non-ELF by default.  So don't put ELF on the
features list when building for OpenBSD, or fix the code to work
correctly in this case instead.

Make orig-modes a gensym in with-float-traps-masked.

as ignored on FreeBSD.

start of the body to support their checking within the body, and
restore these exceptions on exit to allow nesting.

from Raymond Toy.

floating point exceptions disabled. It avoids the overhead of
{set,get}-floating-point-modes, saving some consing and generally
giving smaller code. Exploit this new macro where
{set,get}-floating-point-modes has been used.