lra_reg has an actual_call_used_reg_set field that is only used during
inheritance. This in turn required a special lra_create_live_ranges
pass for flag_ipa_ra to set up this field. This patch instead makes
the inheritance code do its own live register tracking, using the
same ABI-mask-and-clobber-set pair as for IRA.
Tracking ABIs simplifies (and cheapens) the logic in lra-lives.c and
means we no longer need a separate path for -fipa-ra. It also means
we can remove TARGET_RETURN_CALL_WITH_MAX_CLOBBERS.
The patch also strengthens the sanity check in lra_assigns so that
we check that reg_renumber is consistent with the whole conflict set,
not just the call-clobbered registers.
2019-09-30 Richard Sandiford <richard.sandiford@arm.com>
gcc/
* target.def (return_call_with_max_clobbers): Delete.
* doc/tm.texi.in (TARGET_RETURN_CALL_WITH_MAX_CLOBBERS): Delete.
* doc/tm.texi: Regenerate.
* config/aarch64/aarch64.c (aarch64_return_call_with_max_clobbers)
(TARGET_RETURN_CALL_WITH_MAX_CLOBBERS): Delete.
* lra-int.h (lra_reg::actual_call_used_reg_set): Delete.
(lra_reg::call_insn): Delete.
* lra.c: Include function-abi.h.
(initialize_lra_reg_info_element): Don't initialize the fields above.
(lra): Use crtl->abi to test whether the current function needs to
save a register in the prologue. Remove special pre-inheritance
lra_create_live_ranges pass for flag_ipa_ra.
* lra-assigns.c: Include function-abi.h
(find_hard_regno_for_1): Use crtl->abi to test whether the current
function needs to save a register in the prologue.
(lra_assign): Assert that registers aren't allocated to a
conflicting register, rather than checking only for overlaps
with call_used_or_fixed_regs. Do this even for flag_ipa_ra,
and for registers that are not live across a call.
* lra-constraints.c (last_call_for_abi): New variable.
(full_and_partial_call_clobbers): Likewise.
(setup_next_usage_insn): Remove the register from
full_and_partial_call_clobbers.
(need_for_call_save_p): Use call_clobbered_in_region_p to test
whether the register needs a caller save.
(need_for_split_p): Use full_and_partial_reg_clobbers instead
of call_used_or_fixed_regs.
(inherit_in_ebb): Initialize and maintain last_call_for_abi and
full_and_partial_call_clobbers.
* lra-lives.c (check_pseudos_live_through_calls): Replace
last_call_used_reg_set and call_insn arguments with an abi argument.
Remove handling of lra_reg::call_insn. Use function_abi::mode_clobbers
as the set of conflicting registers.
(calls_have_same_clobbers_p): Delete.
(process_bb_lives): Track the ABI of the last call instead of an
insn/HARD_REG_SET pair. Update calls to
check_pseudos_live_through_calls. Use eh_edge_abi to calculate
the set of registers that could be clobbered by an EH edge.
Include partially-clobbered as well as fully-clobbered registers.
(lra_create_live_ranges_1): Don't initialize lra_reg::call_insn.
* lra-remat.c: Include function-abi.h.
(call_used_regs_arr_len, call_used_regs_arr): Delete.
(set_bb_regs): Use insn_callee_abi to get the set of call-clobbered
registers and bitmap_view to combine them into dead_regs.
(call_used_input_regno_present_p): Take a function_abi argument
and use it to test whether a register is call-clobbered.
(calculate_gen_cands): Use insn_callee_abi to get the ABI of the
call insn target. Update tje call to call_used_input_regno_present_p.
(do_remat): Likewise.
(lra_remat): Remove the initialization of call_used_regs_arr_len
and call_used_regs_arr.
From-SVN: r276327
