Divide REG_LABEL notes into REG_LABEL_OPERAND and REG_LABEL_TARGET.

	* doc/rtl.texi (Insns): Specify when a label_ref makes a jump_insn.
	Similar for what label_refs can go in the JUMP_TARGET field.  Split
	REG_LABEL documentation into REG_LABEL_TARGET and REG_LABEL_OPERAND.
	* reload.c (find_reloads): Generate REG_LABEL_OPERAND, not
	REG_LABEL when replacing an operand with a LABEL_REF for a
	non-jump insn.
	(subst_reloads): When replacing a LABEL_REG with a register,
	instead of generating a REG_LABEL note, assert that there already
	is one or that the label is a known target for the insn.
	* rtlanal.c (computed_jump_p): Instead of looking for a REG_LABEL
	note, check the JUMP_LABEL field.  Remove "else" after return.
	* reorg.c (emit_delay_sequence): Replace case for REG_LABEL with
	cases for REG_LABEL_OPERAND and REG_LABEL_TARGET.
	(fill_slots_from_thread): Handle both REG_LABEL_OPERAND and
	REG_LABEL_TARGET notes, including the JUMP_TARGET field on JUMP_P
	insns.  Iterate over all notes; don't assume there's only one.
	* cse.c (recorded_label_ref): Adjust comment to refer to
	REG_LABEL_OPERAND.
	(cse_extended_basic_block): Do LABEL_REF check for all INSN_P
	insns, not just NONJUMP_INSN_P.
	(check_for_label_ref): For JUMP_P insns, check that the LABEL_REF
	isn't a jump target.
	* jump.c (rebuild_jump_labels): Adjust head comment.
	(init_label_info): Ditto.  Remove REG_LABEL_OPERAND notes only;
	don't reset REG_LABEL_TARGET notes, including the JUMP_LABEL field.
	(mark_all_labels): For JUMP_P insns without a target, check if the
	the target is noted on the previous nonjump insn.
	(mark_jump_label_1): New function, guts from mark_jump_label.
	<case IF_THEN_ELSE>: Handle first operand as a non-target when
	marking jump target labels.
	<case LABEL_REF>: Adjust for whether to generate a
	REG_LABEL_TARGET or a REG_LABEL_OPERAND note.
	For 'E' format rtl, iterate in descending element order.
	(delete_related_insns): Handle both REG_LABEL_TARGET and
	REG_LABEL_OPERAND notes.  For JUMP_P insns with labels with zero
	reference count, delete and fallthrough.  Move finding-next-
	non-deleted insn last in the function.  Look at all INSN_P insns
	for REG_LABEL_OPERAND notes.
	(redirect_jump_2): Assert that OLABEL equals the old JUMP_LABEL of
	JUMP.
	* print-rtl.c (print_rtx): For JUMP_P insns and a non-NULL
	JUMP_LABEL, output the INSN_UID of it.
	* gcse.c: Adjust comments as appropriate to say REG_LABEL_OPERAND
	and/or REG_LABEL_TARGET.
	(add_label_notes): Only add REG_LABEL_OPERAND notes.  Put in line
	with jump.c copy by only adding notes for labels actually
	referenced in the insn.
	* emit-rtl.c (try_split): Don't assume only NONJUMP_INSN_P need
	usage count increment; handle all INSN_P trial insns.
	(emit_copy_of_insn_after): Change to not copy REG_LABEL_OPERAND
	notes.
	* rtl.h (struct rtx_def) <volatil>: Adjust to mention
	REG_LABEL_TARGET and REG_LABEL_OPERAND.
	(LABEL_REF_NONLOCAL_P): Allow REG_LABEL_TARGET and
	REG_LABEL_OPERAND.
	* combine.c (distribute_notes): Adjust for REG_LABEL_TARGET on
	JUMP_P insns and REG_LABEL_OPERAND everywhere.
	* sched-rgn.c (is_cfg_nonregular): Check for REG_LABEL_OPERANDS
	on all INSN_P insns.
	* reg-notes.def (LABEL_TARGET, LABEL_OPERAND): Split from LABEL.
	* cfgrtl.c (delete_insn): Adjust to handle REG_LABEL_TARGET and
	REG_LABEL_OPERAND notes.
	* reload1.c (calculate_needs_all_insns): Adjust comments.
	(set_label_offsets): Adjust to look for REG_LABEL_OPERAND notes.
	* config/alpha/alpha.md (split for load of an address into a
	four-insn sequence on Unicos/Mk): Adjust to use
	REG_LABEL_OPERAND.
	* config/sh/sh.md (sh_reorg, final_prescan_insn): Ditto.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@128287 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 14 insertions, 10 deletions

diff --git a/gcc/cse.c b/gcc/cse.c
index c26c6e73efc..7e766611e6e 100644
--- a/gcc/cse.c
+++ b/gcc/cse.c
@@ -353,8 +353,9 @@ static HARD_REG_SET hard_regs_in_table;
 
 static int cse_jumps_altered;
 
-/* Nonzero if we put a LABEL_REF into the hash table for an INSN without a
-   REG_LABEL, we have to rerun jump after CSE to put in the note.  */
+/* Nonzero if we put a LABEL_REF into the hash table for an INSN
+   without a REG_LABEL_OPERAND, we have to rerun jump after CSE to put
+   in the note.  */
 static int recorded_label_ref;
 
 /* canon_hash stores 1 in do_not_record
@@ -6091,7 +6092,7 @@ cse_extended_basic_block (struct cse_basic_block_data *ebb_data)
 	    
 	      /* If we haven't already found an insn where we added a LABEL_REF,
 		 check this one.  */
-	      if (NONJUMP_INSN_P (insn) && ! recorded_label_ref
+	      if (INSN_P (insn) && ! recorded_label_ref
 		  && for_each_rtx (&PATTERN (insn), check_for_label_ref,
 				   (void *) insn))
 		recorded_label_ref = 1;
@@ -6277,23 +6278,26 @@ cse_main (rtx f ATTRIBUTE_UNUSED, int nregs)
   return cse_jumps_altered || recorded_label_ref;
 }
 
-/* Called via for_each_rtx to see if an insn is using a LABEL_REF for which
-   there isn't a REG_LABEL note.  Return one if so.  DATA is the insn.  */
+/* Called via for_each_rtx to see if an insn is using a LABEL_REF for
+   which there isn't a REG_LABEL_OPERAND note.
+   Return one if so.  DATA is the insn.  */
 
 static int
 check_for_label_ref (rtx *rtl, void *data)
 {
   rtx insn = (rtx) data;
 
-  /* If this insn uses a LABEL_REF and there isn't a REG_LABEL note for it,
-     we must rerun jump since it needs to place the note.  If this is a
-     LABEL_REF for a CODE_LABEL that isn't in the insn chain, don't do this
-     since no REG_LABEL will be added.  */
+  /* If this insn uses a LABEL_REF and there isn't a REG_LABEL_OPERAND
+     note for it, we must rerun jump since it needs to place the note.  If
+     this is a LABEL_REF for a CODE_LABEL that isn't in the insn chain,
+     don't do this since no REG_LABEL_OPERAND will be added.  */
   return (GET_CODE (*rtl) == LABEL_REF
 	  && ! LABEL_REF_NONLOCAL_P (*rtl)
+	  && (!JUMP_P (insn)
+	      || !label_is_jump_target_p (XEXP (*rtl, 0), insn))
 	  && LABEL_P (XEXP (*rtl, 0))
 	  && INSN_UID (XEXP (*rtl, 0)) != 0
-	  && ! find_reg_note (insn, REG_LABEL, XEXP (*rtl, 0)));
+	  && ! find_reg_note (insn, REG_LABEL_OPERAND, XEXP (*rtl, 0)));
 }
 
 /* Count the number of times registers are used (not set) in X.