Remove clobber_high

The AArch64 SVE tlsdesc patterns were the main motivating reason
for clobber_high.  It's no longer needed now that the patterns use
calls instead.

At the time, one of the possible future uses for clobber_high was for
asm statements.  However, the current code wouldn't handle that case
without modification, so I think we might as well remove it for now.
We can always reapply it in future if it turns out to be useful again.

2019-10-01  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* rtl.def (CLOBBER_HIGH): Delete.
	* doc/rtl.texi (clobber_high): Remove documentation.
	* rtl.h (SET_DEST): Remove CLOBBER_HIGH from the list of codes.
	(reg_is_clobbered_by_clobber_high): Delete.
	(gen_hard_reg_clobber_high): Likewise.
	* alias.c (record_set): Remove CLOBBER_HIGH handling.
	* cfgexpand.c (expand_gimple_stmt): Likewise.
	* combine-stack-adj.c (single_set_for_csa): Likewise.
	* combine.c (find_single_use_1, set_nonzero_bits_and_sign_copies)
	(can_combine_p, is_parallel_of_n_reg_sets, try_combine)
	(record_dead_and_set_regs_1, reg_dead_at_p_1): Likewise.
	* cse.c (invalidate_reg): Remove clobber_high parameter.
	(invalidate): Update call accordingly.
	(canonicalize_insn): Remove CLOBBER_HIGH handling.
	(invalidate_from_clobbers, invalidate_from_sets_and_clobbers)
	(count_reg_usage, insn_live_p): Likewise.
	* cselib.h (cselib_invalidate_rtx): Remove sett argument.
	* cselib.c (cselib_invalidate_regno, cselib_invalidate_rtx): Likewise.
	(cselib_invalidate_rtx_note_stores): Update call accordingly.
	(cselib_expand_value_rtx_1): Remove CLOBBER_HIGH handling.
	(cselib_invalidate_regno, cselib_process_insn): Likewise.
	* dce.c (deletable_insn_p, mark_nonreg_stores_1): Likewise.
	(mark_nonreg_stores_2): Likewise.
	* df-scan.c (df_find_hard_reg_defs, df_uses_record): Likewise.
	(df_get_call_refs): Likewise.
	* dwarf2out.c (mem_loc_descriptor): Likewise.
	* emit-rtl.c (verify_rtx_sharing): Likewise.
	(copy_insn_1, copy_rtx_if_shared_1): Likewise.
	(hard_reg_clobbers_high, gen_hard_reg_clobber_high): Delete.
	* genconfig.c (walk_insn_part): Remove CLOBBER_HIGH handling.
	* genemit.c (gen_exp, gen_insn): Likewise.
	* genrecog.c (validate_pattern, remove_clobbers): Likewise.
	* haifa-sched.c (haifa_classify_rtx): Likewise.
	* ira-build.c (create_insn_allocnos): Likewise.
	* ira-costs.c (scan_one_insn): Likewise.
	* ira.c (equiv_init_movable_p, memref_referenced_p): Likewise.
	(rtx_moveable_p, interesting_dest_for_shprep): Likewise.
	* jump.c (mark_jump_label_1): Likewise.
	* lra-int.h (lra_insn_reg::clobber_high): Delete.
	* lra-eliminations.c (lra_eliminate_regs_1): Remove CLOBBER_HIGH
	handling.
	(mark_not_eliminable): Likewise.
	* lra-lives.c (process_bb_lives): Likewise.
	* lra.c (new_insn_reg): Remove clobber_high parameter.
	(collect_non_operand_hard_regs): Likewise.  Update call to new
	insn_reg.  Remove CLOBBER_HIGH handling.
	(lra_set_insn_recog_data): Remove CLOBBER_HIGH handling.  Update call
	to collect_non_operand_hard_regs.
	(add_regs_to_insn_regno_info): Remove CLOBBER_HIGH handling.
	Update call to new_insn_reg.
	(lra_update_insn_regno_info): Remove CLOBBER_HIGH handling.
	* postreload.c (reload_cse_simplify, reload_combine_note_use)
	(move2add_note_store): Likewise.
	* print-rtl.c (print_pattern): Likewise.
	* recog.c (store_data_bypass_p_1, store_data_bypass_p): Likewise.
	(if_test_bypass_p): Likewise.
	* regcprop.c (kill_clobbered_value, kill_set_value): Likewise.
	* reginfo.c (reg_scan_mark_refs): Likewise.
	* reload1.c (maybe_fix_stack_asms, eliminate_regs_1): Likewise.
	(elimination_effects, mark_not_eliminable, scan_paradoxical_subregs)
	(forget_old_reloads_1): Likewise.
	* reorg.c (find_end_label, try_merge_delay_insns, redundant_insn)
	(own_thread_p, fill_simple_delay_slots, fill_slots_from_thread)
	(dbr_schedule): Likewise.
	* resource.c (update_live_status, mark_referenced_resources)
	(mark_set_resources): Likewise.
	* rtl.c (copy_rtx): Likewise.
	* rtlanal.c (reg_referenced_p, set_of_1, single_set_2, noop_move_p)
	(note_pattern_stores): Likewise.
	(reg_is_clobbered_by_clobber_high): Delete.
	* sched-deps.c (sched_analyze_reg, sched_analyze_insn): Remove
	CLOBBER_HIGH handling.

From-SVN: r276393

1 files changed, 3 insertions, 45 deletions

diff --git a/gcc/rtlanal.c b/gcc/rtlanal.c
index 6adef47..720aa09 100644
--- a/gcc/rtlanal.c
+++ b/gcc/rtlanal.c
@@ -1216,10 +1216,6 @@ reg_referenced_p (const_rtx x, const_rtx body)
 	  return 1;
       return 0;
 
-    case CLOBBER_HIGH:
-      gcc_assert (REG_P (XEXP (body, 0)));
-      return 0;
-
     case COND_EXEC:
       if (reg_overlap_mentioned_p (x, COND_EXEC_TEST (body)))
 	return 1;
@@ -1442,11 +1438,7 @@ set_of_1 (rtx x, const_rtx pat, void *data1)
 {
   struct set_of_data *const data = (struct set_of_data *) (data1);
   if (rtx_equal_p (x, data->pat)
-      || (GET_CODE (pat) == CLOBBER_HIGH
-	  && REGNO(data->pat) == REGNO(XEXP (pat, 0))
-	  && reg_is_clobbered_by_clobber_high (data->pat, XEXP (pat, 0)))
-      || (GET_CODE (pat) != CLOBBER_HIGH && !MEM_P (x)
-	  && reg_overlap_mentioned_p (data->pat, x)))
+      || (!MEM_P (x) && reg_overlap_mentioned_p (data->pat, x)))
     data->found = pat;
 }
 
@@ -1533,7 +1525,6 @@ single_set_2 (const rtx_insn *insn, const_rtx pat)
 	    {
 	    case USE:
 	    case CLOBBER:
-	    case CLOBBER_HIGH:
 	      break;
 
 	    case SET:
@@ -1687,9 +1678,7 @@ noop_move_p (const rtx_insn *insn)
 	{
 	  rtx tem = XVECEXP (pat, 0, i);
 
-	  if (GET_CODE (tem) == USE
-	      || GET_CODE (tem) == CLOBBER
-	      || GET_CODE (tem) == CLOBBER_HIGH)
+	  if (GET_CODE (tem) == USE || GET_CODE (tem) == CLOBBER)
 	    continue;
 
 	  if (GET_CODE (tem) != SET || ! set_noop_p (tem))
@@ -1923,9 +1912,7 @@ note_pattern_stores (const_rtx x,
   if (GET_CODE (x) == COND_EXEC)
     x = COND_EXEC_CODE (x);
 
-  if (GET_CODE (x) == SET
-      || GET_CODE (x) == CLOBBER
-      || GET_CODE (x) == CLOBBER_HIGH)
+  if (GET_CODE (x) == SET || GET_CODE (x) == CLOBBER)
     {
       rtx dest = SET_DEST (x);
 
@@ -6658,32 +6645,3 @@ tls_referenced_p (const_rtx x)
       return true;
   return false;
 }
-
-/* Return true if reg REGNO with mode REG_MODE would be clobbered by the
-   clobber_high operand in CLOBBER_HIGH_OP.  */
-
-bool
-reg_is_clobbered_by_clobber_high (unsigned int regno, machine_mode reg_mode,
-				  const_rtx clobber_high_op)
-{
-  unsigned int clobber_regno = REGNO (clobber_high_op);
-  machine_mode clobber_mode = GET_MODE (clobber_high_op);
-  unsigned char regno_nregs = hard_regno_nregs (regno, reg_mode);
-
-  /* Clobber high should always span exactly one register.  */
-  gcc_assert (REG_NREGS (clobber_high_op) == 1);
-
-  /* Clobber high needs to match with one of the registers in X.  */
-  if (clobber_regno < regno || clobber_regno >= regno + regno_nregs)
-    return false;
-
-  gcc_assert (reg_mode != BLKmode && clobber_mode != BLKmode);
-
-  if (reg_mode == VOIDmode)
-    return clobber_mode != VOIDmode;
-
-  /* Clobber high will clobber if its size might be greater than the size of
-     register regno.  */
-  return maybe_gt (exact_div (GET_MODE_SIZE (reg_mode), regno_nregs),
-		 GET_MODE_SIZE (clobber_mode));
-}