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| author | Stefan Liebler <stli@linux.vnet.ibm.com> | 2015-08-26 10:26:18 +0200 |
|---|---|---|
| committer | Andreas Krebbel <krebbel@linux.vnet.ibm.com> | 2015-08-26 10:26:18 +0200 |
| commit | 5d96fe8c0dc3450bafe6c2aae2dabc76819df3e0 (patch) | |
| tree | d1b8a2905087b2a7d23d0d0947347667afa800b1 /ChangeLog | |
| parent | f97194930886838796546646e26a49bb5899075b (diff) | |
| download | glibc-5d96fe8c0dc3450bafe6c2aae2dabc76819df3e0.tar.xz glibc-5d96fe8c0dc3450bafe6c2aae2dabc76819df3e0.zip | |
S390: Fix handling of DXC-byte in FPC-register.
On s390, the DXC(data-exception-code)-byte in FPC(floating-point-control)-
register contains a code of the last occured exception.
If bits 6 and 7 of DXC-byte are zero, the bits 0-5 correspond to the
ieee-exception flag bits.
The current implementation always uses these bits as ieee-exception flag bits.
fetestexcept() reports any exception after the first usage of a
vector-instruction in a process, because it raises an "vector instruction
exception" with DXC-code 0xFE.
This patch fixes the handling of the DXC-byte. The DXC-Byte is only handled
if bits 6 and 7 are zero.
The #define _FPU_RESERVED is extended by the DXC-Byte.
Otherwise the tests math/test-fpucw-static and math/test-fpucw-ieee-static
fails, because DXC-Byte contains the vector instruction exception when reaching
main(). This exception was triggered by strrchr() call in __init_misc().
__init_misc() is called after __setfpucw () in __libc_init_first().
The field __ieee_instruction_pointer in struct fenv_t is renamed to __unused
because it is a relict from commit "Remove PTRACE_PEEKUSER"
(87b9b50f0d4b92248905e95a06a13c513dc45e59) and isn´t used anymore.
ChangeLog:
[BZ #18610]
* sysdeps/s390/fpu/bits/fenv.h (fenv_t): Rename
__ieee_instruction_pointer to __unused.
* sysdeps/s390/fpu/fesetenv.c (__fesetenv): Remove usage of
__ieee_instruction_pointer.
* sysdeps/s390/fpu/fclrexcpt.c (feclearexcept): Fix dxc-field handling.
* sysdeps/s390/fpu/fgetexcptflg.c (fegetexceptflag): Likewise.
* sysdeps/s390/fpu/fsetexcptflg.c (fesetexceptflag): Likewise.
* sysdeps/s390/fpu/ftestexcept.c (fetestexcept): Likewise.
* sysdeps/s390/fpu/fpu_control.h (_FPU_RESERVED):
Mark dxc-field as reserved.
Diffstat (limited to 'ChangeLog')
| -rw-r--r-- | ChangeLog | 14 |
1 files changed, 14 insertions, 0 deletions
@@ -1,3 +1,17 @@ +2015-08-26 Stefan Liebler <stli@linux.vnet.ibm.com> + + [BZ #18610] + * sysdeps/s390/fpu/bits/fenv.h (fenv_t): Rename + __ieee_instruction_pointer to __unused. + * sysdeps/s390/fpu/fesetenv.c (__fesetenv): Remove usage of + __ieee_instruction_pointer. + * sysdeps/s390/fpu/fclrexcpt.c (feclearexcept): Fix dxc-field handling. + * sysdeps/s390/fpu/fgetexcptflg.c (fegetexceptflag): Likewise. + * sysdeps/s390/fpu/fsetexcptflg.c (fesetexceptflag): Likewise. + * sysdeps/s390/fpu/ftestexcept.c (fetestexcept): Likewise. + * sysdeps/s390/fpu/fpu_control.h (_FPU_RESERVED): + Mark dxc-field as reserved. + 2015-08-25 Roland McGrath <roland@hack.frob.com> * sysdeps/nacl/start.c (_start): Call __nacl_main instead of main |