Re: [patch 4.1.3] Correctly handle zero operands with gcc on PA

[John David Anglin]

> "John David Anglin" <address@hidden> writes:
> >
> > Here is a small fix to correctly handle zero operands using gcc on the
> > the PA.  See gcc/config/pa.c.
> >
> > 2004-05-24  John David Anglin  <address@hidden>
> >
> >     * longlong.h (add_ssaaaa, sub_ddmmss): Use 'r' modifier with register
> >     or zero operands.
> 
> You need to provide a failing test case.  As far as I know these
> macros work in current usages.

This is the error:

gcc -DHAVE_CONFIG_H -I. -I../../mpn -I.. -D__GMP_WITHIN_GMP -I../.. -DOPERATION_
divrem_1 -O2 -c divrem_1.c  -fPIC -DPIC -o .libs/divrem_1.o
/var/tmp//cc1NtSU6.s: Assembler messages:
/var/tmp//cc1NtSU6.s:119: Error: Invalid Compare/Subtract Condition: db
/var/tmp//cc1NtSU6.s:119: Error: Invalid Compare/Subtract Condition: db
/var/tmp//cc1NtSU6.s:156: Error: Invalid Compare/Subtract Condition: db
/var/tmp//cc1NtSU6.s:156: Error: Invalid Compare/Subtract Condition: db
/var/tmp//cc1NtSU6.s:195: Error: Invalid Compare/Subtract Condition: db
/var/tmp//cc1NtSU6.s:195: Error: Invalid Compare/Subtract Condition: db
/var/tmp//cc1NtSU6.s:285: Error: Invalid Compare/Subtract Condition: db
/var/tmp//cc1NtSU6.s:285: Error: Invalid Compare/Subtract Condition: db
/var/tmp//cc1NtSU6.s:325: Error: Invalid Compare/Subtract Condition: db
/var/tmp//cc1NtSU6.s:325: Error: Invalid Compare/Subtract Condition: db

This is the assembly code generated by gcc on line 119:

        sub,db %r20,0,%r20

The error message from gas is misleading.  The actual error is the
0 in the second operand.  The HP assembler accepts integers for register
numbers, but gas doesn't.  Changing the macro as indicated in the
patch causes the second operand to be output as %r0.  Register r0
always reads as a zero.

This is the gcc version:

# gcc -v
Reading specs from 
/opt/gnu64/gcc/gcc-3.4.0/lib/gcc/hppa64-hp-hpux11.11/3.4.0/specs
Configured with: ../gcc/configure --with-gnu-as --with-as=/opt/gnu64/bin/as 
--with-ld=/usr/ccs/bin/ld --enable-shared --disable-nls 
--with-local-prefix=/opt/gnu64 --prefix=/opt/gnu64/gcc/gcc-3.4.0 
--host=hppa64-hp-hpux11.11 --enable-threads=posix --disable-checking
Thread model: posix
gcc version 3.4.0

This how gmp was configured:

configured by ../configure, generated by GNU Autoconf 2.52,
  with options \"--prefix=/opt/gnu64 --build=hppa2.0w-hp-hpux11.11 
--host=hppa2.0w-hp-hpux11.11 CC=gcc CFLAGS=-O2 CXXFLAGS=-O2 CXX=g++ 
build_alias=hppa2.0w-hp-hpux11.11 host_alias=hppa2.0w-hp-hpux11.11\"

As noted in previous mail, the default config.guess values for the 64-bit
version of gcc need to be overridden to obtain the 2.0w ABI.  It's not
possible to do this directly:

# ../configure ABI=2.0w --prefix=/opt/gnu64         
checking build system type... hppa64-hp-hpux11.11
checking host system type... hppa64-hp-hpux11.11
checking for a BSD compatible install... /opt/gnu/bin/install -c
checking whether build environment is sane... yes
checking for mawk... no
checking for gawk... gawk
checking whether make sets ${MAKE}... yes
checking whether to enable maintainer-specific portions of Makefiles... no
configure: error: ABI=2.0w is not among the following valid choices: standard

Dave
-- 
J. David Anglin                                  address@hidden
National Research Council of Canada              (613) 990-0752 (FAX: 952-6602)