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, 10 insertions, 31 deletions

diff --git a/gcc/cselib.c b/gcc/cselib.c
index 36f649d..500793b 100644
--- a/gcc/cselib.c
+++ b/gcc/cselib.c
@@ -55,8 +55,7 @@ static unsigned int cselib_hash_rtx (rtx, int, machine_mode);
 static cselib_val *new_cselib_val (unsigned int, machine_mode, rtx);
 static void add_mem_for_addr (cselib_val *, cselib_val *, rtx);
 static cselib_val *cselib_lookup_mem (rtx, int);
-static void cselib_invalidate_regno (unsigned int, machine_mode,
-				     const_rtx = NULL);
+static void cselib_invalidate_regno (unsigned int, machine_mode);
 static void cselib_invalidate_mem (rtx);
 static void cselib_record_set (rtx, cselib_val *, cselib_val *);
 static void cselib_record_sets (rtx_insn *);
@@ -1663,7 +1662,6 @@ cselib_expand_value_rtx_1 (rtx orig, struct expand_value_data *evd,
       /* SCRATCH must be shared because they represent distinct values.  */
       return orig;
     case CLOBBER:
-    case CLOBBER_HIGH:
       if (REG_P (XEXP (orig, 0)) && HARD_REGISTER_NUM_P (REGNO (XEXP (orig, 0))))
 	return orig;
       break;
@@ -2166,8 +2164,7 @@ cselib_lookup (rtx x, machine_mode mode,
    invalidating call clobbered registers across a call.  */
 
 static void
-cselib_invalidate_regno (unsigned int regno, machine_mode mode,
-			 const_rtx setter)
+cselib_invalidate_regno (unsigned int regno, machine_mode mode)
 {
   unsigned int endregno;
   unsigned int i;
@@ -2190,9 +2187,6 @@ cselib_invalidate_regno (unsigned int regno, machine_mode mode,
 	i = regno - max_value_regs;
 
       endregno = end_hard_regno (mode, regno);
-
-      if (setter && GET_CODE (setter) == CLOBBER_HIGH)
-	gcc_assert (endregno == regno + 1);
     }
   else
     {
@@ -2225,19 +2219,6 @@ cselib_invalidate_regno (unsigned int regno, machine_mode mode,
 	      continue;
 	    }
 
-	  /* Ignore if clobber high and the register isn't clobbered.  */
-	  if (setter && GET_CODE (setter) == CLOBBER_HIGH)
-	    {
-	      gcc_assert (endregno == regno + 1);
-	      const_rtx x = XEXP (setter, 0);
-	      if (!reg_is_clobbered_by_clobber_high (i, GET_MODE (v->val_rtx),
-						     x))
-		{
-		  l = &(*l)->next;
-		  continue;
-		}
-	    }
-
 	  /* We have an overlap.  */
 	  if (*l == REG_VALUES (i))
 	    {
@@ -2372,10 +2353,10 @@ cselib_invalidate_mem (rtx mem_rtx)
   *vp = &dummy_val;
 }
 
-/* Invalidate DEST, which is being assigned to or clobbered by SETTER.  */
+/* Invalidate DEST.  */
 
 void
-cselib_invalidate_rtx (rtx dest, const_rtx setter)
+cselib_invalidate_rtx (rtx dest)
 {
   while (GET_CODE (dest) == SUBREG
 	 || GET_CODE (dest) == ZERO_EXTRACT
@@ -2383,7 +2364,7 @@ cselib_invalidate_rtx (rtx dest, const_rtx setter)
     dest = XEXP (dest, 0);
 
   if (REG_P (dest))
-    cselib_invalidate_regno (REGNO (dest), GET_MODE (dest), setter);
+    cselib_invalidate_regno (REGNO (dest), GET_MODE (dest));
   else if (MEM_P (dest))
     cselib_invalidate_mem (dest);
 }
@@ -2391,10 +2372,10 @@ cselib_invalidate_rtx (rtx dest, const_rtx setter)
 /* A wrapper for cselib_invalidate_rtx to be called via note_stores.  */
 
 static void
-cselib_invalidate_rtx_note_stores (rtx dest, const_rtx setter,
+cselib_invalidate_rtx_note_stores (rtx dest, const_rtx,
 				   void *data ATTRIBUTE_UNUSED)
 {
-  cselib_invalidate_rtx (dest, setter);
+  cselib_invalidate_rtx (dest);
 }
 
 /* Record the result of a SET instruction.  DEST is being set; the source
@@ -2809,11 +2790,9 @@ cselib_process_insn (rtx_insn *insn)
   if (CALL_P (insn))
     {
       for (x = CALL_INSN_FUNCTION_USAGE (insn); x; x = XEXP (x, 1))
-	{
-	  gcc_assert (GET_CODE (XEXP (x, 0)) != CLOBBER_HIGH);
-	  if (GET_CODE (XEXP (x, 0)) == CLOBBER)
-	    cselib_invalidate_rtx (XEXP (XEXP (x, 0), 0));
-	}
+	if (GET_CODE (XEXP (x, 0)) == CLOBBER)
+	  cselib_invalidate_rtx (XEXP (XEXP (x, 0), 0));
+
       /* Flush everything on setjmp.  */
       if (cselib_preserve_constants
 	  && find_reg_note (insn, REG_SETJMP, NULL))