[Bug target/27772] New: mr instruction with odd-numbered register created

[rguenth at gcc dot gnu dot org]

I get testsuite failures in mpfr compiling for s390 with

/usr/lib/gcc/s390-suse-linux/4.1.0/cc1 -fpreprocessed mul.i -quiet -dumpbase
mul.c -march=z900 -mtune=z9-109 -m31 -mesa -auxbase mul -O2 -Wall -version
-fmessage-length=0 -fPIC -o mul.s

s390z27:/usr/src/packages/BUILD/mpfr-2.2.0/tests# LD_LIBRARY_PATH=../.libs/ gdb
.libs/tcheck 
GNU gdb 6.4.90.20060522
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "s390-suse-linux"...Using host libthread_db library
"/lib/libthread_db.so.1".

(gdb) run
Starting program: /usr/src/packages/BUILD/mpfr-2.2.0/tests/.libs/tcheck 

Program received signal SIGILL, Illegal instruction.
0x400c0902 in mpfr_mul () from ../.libs/libmpfr.so.1
(gdb) disassemble
...
0x400c08f6 <mpfr_mul+802>:      sra     %r5,31
0x400c08fa <mpfr_mul+806>:      l       %r1,0(%r3)
0x400c08fe <mpfr_mul+810>:      lr      %r4,%r2
0x400c0900 <mpfr_mul+812>:      mr      %r3,%r1
0x400c0902 <mpfr_mul+814>:      nr      %r5,%r1
0x400c0904 <mpfr_mul+816>:      sra     %r1,31
0x400c0908 <mpfr_mul+820>:      ar      %r5,%r3
0x400c090a <mpfr_mul+822>:      nr      %r2,%r1

where the only thing I notice is 'mr %r3,%r1' which seems to contradict
the requirement of an even-numbered register for the destination argument.

Note that even with -march=g5 odd-numbered target registers are produced
for mr.  I'll attach preprocessed source for mul.i.


-- 
           Summary: mr instruction with odd-numbered register created
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: rguenth at gcc dot gnu dot org
GCC target triplet: s390-ibm-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27772