84 строки
3.9 KiB
Plaintext
84 строки
3.9 KiB
Plaintext
2002-01-19 Russell King <rmk@arm.linux.org.uk>
|
|
|
|
* fpa11.h - Add documentation
|
|
- remove userRegisters pointer from this structure.
|
|
- add new method to obtain integer register values.
|
|
* softfloat.c - Remove float128
|
|
* softfloat.h - Remove float128
|
|
* softfloat-specialize - Remove float128
|
|
|
|
* The FPA11 structure is not a kernel-specific data structure.
|
|
It is used by users of ptrace to examine the values of the
|
|
floating point registers. Therefore, any changes to the
|
|
FPA11 structure (size or position of elements contained
|
|
within) have to be well thought out.
|
|
|
|
* Since 128-bit float requires the FPA11 structure to change
|
|
size, it has been removed. 128-bit float is currently unused,
|
|
and needs various things to be re-worked so that we won't
|
|
overflow the available space in the task structure.
|
|
|
|
* The changes are designed to break any patch that goes on top
|
|
of this code, so that the authors properly review their changes.
|
|
|
|
1999-08-19 Scott Bambrough <scottb@netwinder.org>
|
|
|
|
* fpmodule.c - Changed version number to 0.95
|
|
* fpa11.h - modified FPA11, FPREG structures
|
|
* fpa11.c - Changes due to FPA11, FPREG structure alterations.
|
|
* fpa11_cpdo.c - Changes due to FPA11, FPREG structure alterations.
|
|
* fpa11_cpdt.c - Changes due to FPA11, FPREG structure alterations.
|
|
* fpa11_cprt.c - Changes due to FPA11, FPREG structure alterations.
|
|
* single_cpdo.c - Changes due to FPA11, FPREG structure alterations.
|
|
* double_cpdo.c - Changes due to FPA11, FPREG structure alterations.
|
|
* extended_cpdo.c - Changes due to FPA11, FPREG structure alterations.
|
|
|
|
* I discovered several bugs. First and worst is that the kernel
|
|
passes in a pointer to the FPE's state area. This is defined
|
|
as a struct user_fp (see user.h). This pointer was cast to a
|
|
FPA11*. Unfortunately FPA11 and user_fp are of different sizes;
|
|
user_fp is smaller. This meant that the FPE scribbled on things
|
|
below its area, which is bad, as the area is in the thread_struct
|
|
embedded in the process task structure. Thus we were scribbling
|
|
over one of the most important structures in the entire OS.
|
|
|
|
* user_fp and FPA11 have now been harmonized. Most of the changes
|
|
in the above code were dereferencing problems due to moving the
|
|
register type out of FPREG, and getting rid of the union variable
|
|
fpvalue.
|
|
|
|
* Second I noticed resetFPA11 was not always being called for a
|
|
task. This should happen on the first floating point exception
|
|
that occurs. It is controlled by init_flag in FPA11. The
|
|
comment in the code beside init_flag state the kernel guarantees
|
|
this to be zero. Not so. I found that the kernel recycles task
|
|
structures, and that recycled ones may not have init_flag zeroed.
|
|
I couldn't even find anything that guarantees it is zeroed when
|
|
when the task structure is initially allocated. In any case
|
|
I now initialize the entire FPE state in the thread structure to
|
|
zero when allocated and recycled. See alloc_task_struct() and
|
|
flush_thread() in arch/arm/process.c. The change to
|
|
alloc_task_struct() may not be necessary, but I left it in for
|
|
completeness (better safe than sorry).
|
|
|
|
1998-11-23 Scott Bambrough <scottb@netwinder.org>
|
|
|
|
* README.FPE - fix typo in description of lfm/sfm instructions
|
|
* NOTES - Added file to describe known bugs/problems
|
|
* fpmodule.c - Changed version number to 0.94
|
|
|
|
1998-11-20 Scott Bambrough <scottb@netwinder.org>
|
|
|
|
* README.FPE - fix description of URD, NRM instructions
|
|
* TODO - remove URD, NRM instructions from TODO list
|
|
* single_cpdo.c - implement URD, NRM
|
|
* double_cpdo.c - implement URD, NRM
|
|
* extended_cpdo.c - implement URD, NRM
|
|
|
|
1998-11-19 Scott Bambrough <scottb@netwinder.org>
|
|
|
|
* ChangeLog - Added this file to track changes made.
|
|
* fpa11.c - added code to initialize register types to typeNone
|
|
* fpa11_cpdt.c - fixed bug in storeExtended (typeExtended changed to
|
|
typeDouble in switch statement)
|