The following patch fixes
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58335
It required to implement a new approach for elimination updates for
insn frame_pointer = hard_frame_pointer + offset. The previous
implementation used parsing insns generated for offset elimination for
given insn. It is hard to parse all possible variants for such
elimination on different targets. For example, s390 code is quite
different from x86/x86-64 code and that was the reason for the PR.
The new implementation uses temporarily REG_EQUAL notes to avoid
generated insns
parsing. It solves the problem and makes LRA more portable.
The patch was successfully bootstrapped and tested on x86/x86-64 and s390.
Committed as rev. 202536.
2013-09-12 Vladimir Makarov <vmaka...@redhat.com>
PR middle-end/58335
* lra-eliminations.c (remove_reg_equal_offset_note): New.
(eliminate_regs_in_insn): Rewrite frame pointer to hard frame
pointer elimination with using remove_reg_equal_offset_note.
