On 02/08/13 16:36, Peter Bergner wrote:
> On Fri, 2013-08-02 at 16:26 +0200, Andreas Krebbel wrote:
>> On 02/08/13 16:23, Peter Bergner wrote:
>> As long as libitm does not use FPRs itself this should be safe without
>> having tbegin clobbering FPRs.
>
> Is it a given that s390 doesn't use FPRs without explicit use of
> floating point types? I ask, because on POWER, we can and do
> generate floating point code without explicit use of double,
> float, etc. Maybe s390 is safe in that respect.
S/390 used to be on the safe side regarding this but with mainline we started
using FPRs as GPR save
slots. As Richard suggested we should build libitm with -msoft-float in order
to prevent this within
libitm. Unfortunately I forgot about this in my S/390 libitm patch. So I'll
commit the following:
Index: libitm/configure.tgt
===================================================================
*** libitm/configure.tgt.orig 2013-07-30 07:42:29.000000000 +0000
--- libitm/configure.tgt 2013-08-02 14:43:18.641206151 +0000
*************** case "${target_cpu}" in
*** 109,115 ****
ARCH=x86
;;
s390|s390x)
! XCFLAGS="${XCFLAGS} -mzarch -mhtm"
ARCH=s390
;;
--- 109,115 ----
ARCH=x86
;;
s390|s390x)
! XCFLAGS="${XCFLAGS} -mzarch -mhtm -msoft-float"
ARCH=s390
;;
