[PATCH, SMS] Support instructions with REG_INC_NOTE (re-submisson)

[Revital Eres <revital dot eres at linaro dot org>]

Hello,

This is a re-submission of the patch to support instructions with REG_INC_NOTE.
(http://gcc.gnu.org/ml/gcc-patches/2011-04/msg01309.html)

It contains a minor change from the previous submission suggested by
Richard Sandiford: to use reg_referenced_p instead of
rtx_referenced_p.

The patch supports instructions with auto inc/dec operations as to
support such instructions we can not assume that there is only one
definition in the instruction. This assumption is currently used to
generate reg-moves information. Because the auto inc/dec instruction
defines more then one register we need to generate different reg-moves
for each of the definitions. At some point in the SMS procedure we
need to find
the first reg-move generated for a specific definition(*) and if there
is more than one definition in the instruction (lets call it insn1)
we can not simply assume it's first reg-move instruction is the first
instruction right before insn1.

for example, the following instruction defines two variables: x and i:
x = mem [POST_INC (i)]

lets say both of them need reg-move

insn 1) reg_move_i = i
insn 2) reg_move_x = x
insn 3) x = mem [POST_INC (i)]

then in order to reach the first reg-move of i we can not just go to
insn 2 like in the current implementation, so we need to save for each
definition in the instruction it's first reg-move instruction.

(*) I'm referring to the generation of prologue and epilogue
(duplicate_insns_of_cycles) which uses first_reg_move field in
node_sched_params structure, and SCHED_FIRST_REG_MOVE definition in
modulo-sched.c.

Reg-tested and bootstrap on ppc64-redhat-linux enabling SMS on loops with SC 1.

OK for mainline?

Thanks,
Revital


        * modulo-sched.c (record_inc_dec_insn_info,
        free_node_sched_params): New functions.
        (SCHED_FIRST_REG_MOVE, SCHED_NREG_MOVES): Remove.
        (struct regmove_info): New.
        (insn_regmove_info): New field in node_sched_params.
        (print_node_sched_params): Print information for all the
        definitions in the instructions.
        (generate_reg_moves, duplicate_insns_of_cycles,
        set_node_sched_params): Adjust the code to handle instructions
        that have multiple definitions.
        (sms_schedule): Handle loops that contain instructions with
        FIND_REG_INC_NOTE and call free_node_sched_params.

Attachment: patch_sms_auto_inc_dec_11_8.txt
Description: Text document