* emit-rtl.c (set_unique_reg_note): Don't create REG_EQUAL or

	REG_EQUIV notes for ASM_OPERANDS.  Return the new note (if any).
	* rtl.h (set_unique_reg_note): Change return value.
	* gcse.c (try_replace_reg): Use set_unique_reg_note.
	* cse.c (cse_insn): Likewise.
	* expr.c (emit_move_insn): Likewise.
	* explow.c (force_reg): Likewise.
	* local-alloc (update_equiv_regs): Likewise.
	* loop.c (move_moveables, load_mems): Likewise.
	* reload (find_reloads): Likewise.

	* gcc.dg/20011029-2.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@46636 138bc75d-0d04-0410-961f-82ee72b054a4

11 files changed, 46 insertions, 43 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index dabf4f7ecc4..94976b36047 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,16 @@
+2001-10-30  Jakub Jelinek  <jakub@redhat.com>
+
+	* emit-rtl.c (set_unique_reg_note): Don't create REG_EQUAL or
+	REG_EQUIV notes for ASM_OPERANDS.  Return the new note (if any).
+	* rtl.h (set_unique_reg_note): Change return value.
+	* gcse.c (try_replace_reg): Use set_unique_reg_note.
+	* cse.c (cse_insn): Likewise.
+	* expr.c (emit_move_insn): Likewise.
+	* explow.c (force_reg): Likewise.
+	* local-alloc (update_equiv_regs): Likewise.
+	* loop.c (move_moveables, load_mems): Likewise.
+	* reload (find_reloads): Likewise.
+
 2001-10-30  Paolo Bonzini  <bonzini@gnu.org>
 
 	Localization fixes.
diff --git a/gcc/cse.c b/gcc/cse.c
index cbeae55f72f..ad6c62030fe 100644
--- a/gcc/cse.c
+++ b/gcc/cse.c
@@ -5648,18 +5648,12 @@ cse_insn (insn, libcall_insn)
 		&& GET_CODE (XEXP (XEXP (src_const, 0), 0)) == LABEL_REF
 		&& GET_CODE (XEXP (XEXP (src_const, 0), 1)) == LABEL_REF))
 	{
-	  tem = find_reg_note (insn, REG_EQUAL, NULL_RTX);
-
 	  /* Make sure that the rtx is not shared with any other insn.  */
 	  src_const = copy_rtx (src_const);
 
 	  /* Record the actual constant value in a REG_EQUAL note, making
 	     a new one if one does not already exist.  */
-	  if (tem)
-	    XEXP (tem, 0) = src_const;
-	  else
-	    REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_EQUAL,
-						  src_const, REG_NOTES (insn));
+	  set_unique_reg_note (insn, REG_EQUAL, src_const);
 
           /* If storing a constant value in a register that
 	     previously held the constant value 0,
diff --git a/gcc/emit-rtl.c b/gcc/emit-rtl.c
index 008ceaadcba..992d6049781 100644
--- a/gcc/emit-rtl.c
+++ b/gcc/emit-rtl.c
@@ -3960,7 +3960,7 @@ force_next_line_note ()
 /* Place a note of KIND on insn INSN with DATUM as the datum. If a
    note of this type already exists, remove it first.  */
 
-void
+rtx
 set_unique_reg_note (insn, kind, datum)
      rtx insn;
      enum reg_note kind;
@@ -3968,11 +3968,20 @@ set_unique_reg_note (insn, kind, datum)
 {
   rtx note = find_reg_note (insn, kind, NULL_RTX);
 
-  /* First remove the note if there already is one.  */
+  /* Don't add ASM_OPERAND REG_EQUAL/REG_EQUIV notes.
+     It serves no useful purpose and breaks eliminate_regs.  */
+  if ((kind == REG_EQUAL || kind == REG_EQUIV)
+      && GET_CODE (datum) == ASM_OPERANDS)
+    return NULL_RTX;
+
   if (note)
-    remove_note (insn, note);
+    {
+      XEXP (note, 0) = datum;
+      return note;
+    }
 
   REG_NOTES (insn) = gen_rtx_EXPR_LIST (kind, datum, REG_NOTES (insn));
+  return REG_NOTES (insn);
 }
 
 /* Return an indication of which type of insn should have X as a body.
diff --git a/gcc/explow.c b/gcc/explow.c
index d0735aab78a..940a8395191 100644
--- a/gcc/explow.c
+++ b/gcc/explow.c
@@ -743,14 +743,7 @@ force_reg (mode, x)
   if (CONSTANT_P (x)
       && (set = single_set (insn)) != 0
       && SET_DEST (set) == temp)
-    {
-      rtx note = find_reg_note (insn, REG_EQUAL, NULL_RTX);
-
-      if (note)
-	XEXP (note, 0) = x;
-      else
-	REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_EQUAL, x, REG_NOTES (insn));
-    }
+    set_unique_reg_note (insn, REG_EQUAL, x);
   return temp;
 }
 
diff --git a/gcc/expr.c b/gcc/expr.c
index b5c5989991f..bf7ec926d7e 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -2774,8 +2774,7 @@ emit_move_insn (x, y)
   last_insn = emit_move_insn_1 (x, y);
 
   if (y_cst && GET_CODE (x) == REG)
-    REG_NOTES (last_insn)
-      = gen_rtx_EXPR_LIST (REG_EQUAL, y_cst, REG_NOTES (last_insn));
+    set_unique_reg_note (last_insn, REG_EQUAL, y_cst);
 
   return last_insn;
 }
diff --git a/gcc/gcse.c b/gcc/gcse.c
index a91cfd6836e..0bd96e02e4e 100644
--- a/gcc/gcse.c
+++ b/gcc/gcse.c
@@ -3929,8 +3929,7 @@ try_replace_reg (from, to, insn)
   /* If we've failed to do replacement, have a single SET, and don't already
      have a note, add a REG_EQUAL note to not lose information.  */
   if (!success && note == 0 && set != 0)
-    note = REG_NOTES (insn)
-      = gen_rtx_EXPR_LIST (REG_EQUAL, src, REG_NOTES (insn));
+    note = set_unique_reg_note (insn, REG_EQUAL, src);
 
   /* If there is already a NOTE, update the expression in it with our
      replacement.  */
diff --git a/gcc/local-alloc.c b/gcc/local-alloc.c
index 9945b45d14b..7cee3f5e456 100644
--- a/gcc/local-alloc.c
+++ b/gcc/local-alloc.c
@@ -927,13 +927,9 @@ update_equiv_regs ()
 
 	  /* cse sometimes generates function invariants, but doesn't put a
 	     REG_EQUAL note on the insn.  Since this note would be redundant,
-	     there's no point creating it earlier than here.  Don't do this
-	     for ASM_OPERANDS since eliminate_regs doesn't support it and
-	     it serves no useful purpose.  */
-	  if (! note && ! rtx_varies_p (src, 0)
-	      && GET_CODE (src) != ASM_OPERANDS)
-	    REG_NOTES (insn)
-	      = note = gen_rtx_EXPR_LIST (REG_EQUAL, src, REG_NOTES (insn));
+	     there's no point creating it earlier than here.  */
+	  if (! note && ! rtx_varies_p (src, 0))
+	    note = set_unique_reg_note (insn, REG_EQUAL, src);
 
 	  /* Don't bother considering a REG_EQUAL note containing an EXPR_LIST
 	     since it represents a function call */
diff --git a/gcc/loop.c b/gcc/loop.c
index baaa74b59ab..8b2f8daf013 100644
--- a/gcc/loop.c
+++ b/gcc/loop.c
@@ -1831,9 +1831,9 @@ move_movables (loop, movables, threshold, insn_count)
 
 		  i1 = loop_insn_hoist (loop, seq);
 		  if (! find_reg_note (i1, REG_EQUAL, NULL_RTX))
-		    REG_NOTES (i1)
-		      = gen_rtx_EXPR_LIST (m->is_equiv ? REG_EQUIV : REG_EQUAL,
-					   m->set_src, REG_NOTES (i1));
+		    set_unique_reg_note (i1,
+					 m->is_equiv ? REG_EQUIV : REG_EQUAL,
+					 m->set_src);
 
 		  if (loop_dump_stream)
 		    fprintf (loop_dump_stream, " moved to %d", INSN_UID (i1));
@@ -1991,10 +1991,8 @@ move_movables (loop, movables, threshold, insn_count)
 
 			  i1 = loop_insn_hoist (loop, seq);
 			  if (! find_reg_note (i1, REG_EQUAL, NULL_RTX))
-			    REG_NOTES (i1)
-			      = gen_rtx_EXPR_LIST ((m->is_equiv ? REG_EQUIV
-						    : REG_EQUAL),
-						   m->set_src, REG_NOTES (i1));
+			    set_unique_reg_note (i1, m->is_equiv ? REG_EQUIV
+						     : REG_EQUAL, m->set_src);
 			}
 		      else
 			i1 = loop_insn_hoist (loop, PATTERN (p));
@@ -9136,9 +9134,7 @@ load_mems (loop)
 	    }
 
 	  if (const_equiv)
-	    REG_NOTES (set) = gen_rtx_EXPR_LIST (REG_EQUAL,
-						 copy_rtx (const_equiv->loc),
-						 REG_NOTES (set));
+	    set_unique_reg_note (set, REG_EQUAL, copy_rtx (const_equiv->loc));
 
 	  if (written)
 	    {
diff --git a/gcc/reload.c b/gcc/reload.c
index 2e8c93fbe98..9ed9cd09948 100644
--- a/gcc/reload.c
+++ b/gcc/reload.c
@@ -2666,9 +2666,9 @@ find_reloads (insn, replace, ind_levels, live_known, reload_reg_p)
 	      && GET_CODE (reg) == REG
 	      && (GET_MODE_SIZE (GET_MODE (reg))
 		  >= GET_MODE_SIZE (GET_MODE (op))))
-	    REG_NOTES (emit_insn_before (gen_rtx_USE (VOIDmode, reg), insn))
-	      = gen_rtx_EXPR_LIST (REG_EQUAL,
-				   reg_equiv_memory_loc[REGNO (reg)], NULL_RTX);
+	    set_unique_reg_note (emit_insn_before (gen_rtx_USE (VOIDmode, reg),
+						   insn),
+				 REG_EQUAL, reg_equiv_memory_loc[REGNO (reg)]);
 
 	  substed_operand[i] = recog_data.operand[i] = op;
 	}
diff --git a/gcc/rtl.h b/gcc/rtl.h
index 1985f98ea4b..db1e913be44 100644
--- a/gcc/rtl.h
+++ b/gcc/rtl.h
@@ -1409,7 +1409,7 @@ extern enum machine_mode choose_hard_reg_mode PARAMS ((unsigned int,
 						       unsigned int));
 
 /* In emit-rtl.c  */
-extern void set_unique_reg_note         PARAMS ((rtx, enum reg_note, rtx));
+extern rtx set_unique_reg_note		PARAMS ((rtx, enum reg_note, rtx));
 
 /* Functions in rtlanal.c */
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 2556eb47f28..d8f07d99732 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2001-10-30  Jakub Jelinek  <jakub@redhat.com>
+
+	* gcc.dg/20011029-2.c: New test.
+
 Mon Oct 29 21:19:53 2001  Nicola Pero  <n.pero@mi.flashnet.it>
 
 	* objc/execute/class_self-1.m: New test.