This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Re: [PATCH 01/27] S390: Fix handling of DXC-byte in FPC-register.
- From: Joseph Myers <joseph at codesourcery dot com>
- To: Stefan Liebler <stli at linux dot vnet dot ibm dot com>
- Cc: <libc-alpha at sourceware dot org>
- Date: Fri, 26 Jun 2015 20:53:38 +0000
- Subject: Re: [PATCH 01/27] S390: Fix handling of DXC-byte in FPC-register.
- Authentication-results: sourceware.org; auth=none
- References: <1435319512-22245-1-git-send-email-stli at linux dot vnet dot ibm dot com> <1435319512-22245-2-git-send-email-stli at linux dot vnet dot ibm dot com>
On Fri, 26 Jun 2015, Stefan Liebler wrote:
> 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.
Was this issue user-visible in existing releases (for user programs using
vector instructions)? If so, please file the usual bug in Bugzilla, put
the [BZ #N] notation in the ChangeLog entry, add to NEWS and close the bug
when committing.
--
Joseph S. Myers
joseph@codesourcery.com