[PATCH v2] PR48344: Fix unrecognizable insn error when gcc

[Kelvin Nilsen <kdnilsen at linux dot vnet dot ibm dot com>]

This patch has bootstrapped and tested on powerpc64le-unknown-linux-gnu 
with no regressions.  Is this ok for the trunk?

See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=48344 for the original 
problem report.  The error resulted because gcc's processing of 
command-line options within gcc initialization code originally preceded 
the processing of target-specific configuration hooks.

In the unpatched gcc implementation, the Pmode (pointer mode) variable 
has not been initialized at the time the -fstack-limit-register 
command-line option is processed.  As a consequence, the stack-limiting 
register is not assigned a proper mode.  Thus, rtl instructions that 
make use of this stack-limiting register have an unspecified mode, and 
are therefore not matched by any known instructions.

The fix represented in this patch is to move the invocation of 
process_options () from within the implementation of do_compile () to 
immediately preceding the invocation of handle_common_deferred_options 
() (inside toplev::main ()).

gcc/ChangeLog:

2016-01-14  Kelvin Nilsen <kelvin@gcc.gnu.org>

    * toplev.c (do_compile): remove invocation of process_options ()
        from within do_compile ()
    (toplev::main): insert invocation of process_options () before
        invocation of handle_common_deferred_options ().

gcc/testsuite/ChangeLog:

2016-01-14  Kelvin Nilsen <kelvin@gcc.gnu.org>

    * gcc.target/powerpc/pr48344-1.c: New test.

Attachment: svn.diffs.1-20-2016
Description: Text document