[Bug rtl-optimization/44194] struct returned by value generates useless stores

[ebotcazou at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44194

--- Comment #46 from Eric Botcazou <ebotcazou at gcc dot gnu.org> 2012-09-14 13:28:52 UTC ---
Author: ebotcazou
Date: Fri Sep 14 13:28:44 2012
New Revision: 191302

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=191302
Log:
    PR rtl-optimization/44194
    * calls.c (expand_call): In the PARALLEL case, copy the return value
    into pseudos instead of spilling it onto the stack.
    * emit-rtl.c (adjust_address_1): Rename ADJUST into ADJUST_ADDRESS and
    add new ADJUST_OBJECT parameter.
    If ADJUST_OBJECT is set, drop the underlying object if it cannot be
    proved that the adjusted memory access is still within its bounds.
    (adjust_automodify_address_1): Adjust call to adjust_address_1.
    (widen_memory_access): Likewise.
    * expmed.c (store_bit_field_1): Call adjust_bitfield_address instead
    of adjust_address.  Do not drop the underlying object of a MEM.
    (store_fixed_bit_field): Likewise.
    (extract_bit_field_1): Likewise.  Fix oversight in recursion.
    (extract_fixed_bit_field): Likewise.
    * expr.h (adjust_address_1): Adjust prototype.
    (adjust_address): Adjust call to adjust_address_1.
    (adjust_address_nv): Likewise.
    (adjust_bitfield_address): New macro.
    (adjust_bitfield_address_nv): Likewise.
    * expr.c (expand_assignment): Handle a PARALLEL in more cases.
    (store_expr): Likewise.
    (store_field): Likewise.

    * dse.c: Fix typos in the head comment.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/calls.c
    trunk/gcc/dse.c
    trunk/gcc/emit-rtl.c
    trunk/gcc/expmed.c
    trunk/gcc/expr.c
    trunk/gcc/expr.h
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/pr44194-1.c