Use mips3 as the default MIPS ISA for 32-bit FreeBSD/mips.

The in-tree GCC 4.2.1 defaults to a MIPS ISA of MIPS3 (which includes ll
and sc instructions needed for SMP-aware atomics).  However, out of the
box GCC defaults to MIPS1 for 32-bit MIPS (N32 and N64 both require a
minimum of MIPS3).  Change both devel/mips-gcc and base/gcc to default to
MIPS3 for 32-bit MIPS on FreeBSD.
- Fix the default target cpu to include MASK_ABICALLS in configure.tgt.
  The gcc/config/mips/freebsd.h header already overrides this anway, but
  it is more correct to fix this here.  We could perhaps remove the
  hack from freebsd.h now but I haven't done that.
- Fix the case that checks for 32-bit mips tuples to match on 'mips*'
  instead of 'mips32*' in configure.tgt.  We don't use mips32* in our
  tuples for O32 MIPS.
- Set MIPS_ISA_DEFAULT to 3 (MIPS3) rather than 33 (MIPS32R6 or some such)
  for O32.
- Remove MIPS_ISA_DEFAULT for N32 to use the default of MIPS3.
- Remove hackish driver specs and instead replace with more standard
  driver specs.  Add MIPS_DEFAULT_ISA_LEVEL_SPEC to the default driver
  specs.  This macro forces a suitable MIPS ISA parameter (such as -mips3)
  to always be added to the flags passed to subcommands.  In particular,
  without this change the compiler would assume MIPS3 by default via
  MIPS_ISA_DEFAULT but would not pass any flags on to as(1) and as
  would still use MIPS1.  The added macro ensures -mips3 is passed to
  as(1) if no explicit -march is specified.

The upshot of all this is that one no longer has to explicitly specify
TARGET_CPUTYPE=mips3 to build O32 MIPS.  It should also make /usr/bin/cc
from base/gcc more compatible with GCC 4.2.1.

Reviewed by:	bapt
Differential Revision:	https://reviews.freebsd.org/D15543

0 files changed, 0 insertions, 0 deletions