From fe4b3c7996410a60bd1b9164eae31bc3946deded Mon Sep 17 00:00:00 2001
From: Jeff Law <law@redhat.com>
Date: Mon, 13 May 2002 22:15:57 -0600
Subject: [PATCH] flow.c (invalidate_mems_from_autoinc): Rewrite to use
 for_each_rtx.

        * flow.c (invalidate_mems_from_autoinc): Rewrite to use for_each_rtx.
        Update prototype and callers.
        (propagate_one_insn): Stack pointer adjustments kill MEMs on
        the mem_set_list which reference the stack pointer, as do
        calls to constant functions as they may clobber outgoing
        argument space.

From-SVN: r53442
---
 gcc/ChangeLog |  7 +++++++
 gcc/flow.c    | 46 ++++++++++++++++++++++++++--------------------
 2 files changed, 33 insertions(+), 20 deletions(-)

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 87181b40b1f..95760b39a7d 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -23,6 +23,13 @@
 
 2002-05-13  Jeffrey A Law  (law@redhat.com)
 
+	* flow.c (invalidate_mems_from_autoinc): Rewrite to use for_each_rtx.
+	Update prototype and callers.
+	(propagate_one_insn): Stack pointer adjustments kill MEMs on
+	the mem_set_list which reference the stack pointer, as do
+	calls to constant functions as they may clobber outgoing
+	argument space.
+
 	* i386.c (ia32_multipass_dfa_lookahead): Prototype.
 
 	* i386.c (TARGET_SCHED_FIRST_CYCLE_MULTIPASS_DFA_LOOKAHEAD): Define.
diff --git a/gcc/flow.c b/gcc/flow.c
index 380c3d3421d..8a9a9db1a45 100644
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -338,8 +338,7 @@ void dump_flow_info			PARAMS ((FILE *));
 void debug_flow_info			PARAMS ((void));
 static void add_to_mem_set_list		PARAMS ((struct propagate_block_info *,
 						 rtx));
-static void invalidate_mems_from_autoinc PARAMS ((struct propagate_block_info *,
-						  rtx));
+static int invalidate_mems_from_autoinc PARAMS ((rtx *, void *));
 static void invalidate_mems_from_set	PARAMS ((struct propagate_block_info *,
 						 rtx));
 static void clear_log_links		PARAMS ((sbitmap));
@@ -1715,8 +1714,9 @@ propagate_one_insn (pbi, insn)
     /* We have an insn to pop a constant amount off the stack.
        (Such insns use PLUS regardless of the direction of the stack,
        and any insn to adjust the stack by a constant is always a pop.)
-       These insns, if not dead stores, have no effect on life.  */
-    ;
+       These insns, if not dead stores, have no effect on life, though
+       they do have an effect on the memory stores we are tracking.  */
+    invalidate_mems_from_set (pbi, stack_pointer_rtx);
   else
     {
       rtx note;
@@ -1741,12 +1741,16 @@ propagate_one_insn (pbi, insn)
 	  if (GET_CODE (PATTERN (insn)) == COND_EXEC)
 	    cond = COND_EXEC_TEST (PATTERN (insn));
 
-	  /* Non-constant calls clobber memory.  */
+	  /* Non-constant calls clobber memory, constant calls do not
+	     clobber memory, though they may clobber outgoing arguments
+	     on the stack.  */
 	  if (! CONST_OR_PURE_CALL_P (insn))
 	    {
 	      free_EXPR_LIST_list (&pbi->mem_set_list);
 	      pbi->mem_set_list_len = 0;
 	    }
+          else
+	    invalidate_mems_from_set (pbi, stack_pointer_rtx);
 
 	  /* There may be extra registers to be clobbered.  */
 	  for (note = CALL_INSN_FUNCTION_USAGE (insn);
@@ -2415,15 +2419,21 @@ add_to_mem_set_list (pbi, mem)
    Find any entries on the mem_set_list that need to be invalidated due
    to an address change.  */
 
-static void
-invalidate_mems_from_autoinc (pbi, insn)
-     struct propagate_block_info *pbi;
-     rtx insn;
+static int
+invalidate_mems_from_autoinc (px, data)
+     rtx *px;
+     void *data;
 {
-  rtx note = REG_NOTES (insn);
-  for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
-    if (REG_NOTE_KIND (note) == REG_INC)
-      invalidate_mems_from_set (pbi, XEXP (note, 0));
+  rtx x = *px;
+  struct propagate_block_info *pbi = data;
+
+  if (GET_RTX_CLASS (GET_CODE (x)) == 'a')
+    {
+      invalidate_mems_from_set (pbi, XEXP (x, 0));
+      return -1;
+    }
+
+  return 0;
 }
 
 /* EXP is a REG.  Remove any dependent entries from pbi->mem_set_list.  */
@@ -2645,15 +2655,11 @@ mark_set_1 (pbi, code, reg, cond, insn, flags)
 	 address modes.  Then we may need to kill some entries on the
 	 memory set list.  */
       if (insn && GET_CODE (reg) == MEM)
-	invalidate_mems_from_autoinc (pbi, insn);
+	for_each_rtx (&PATTERN (insn), invalidate_mems_from_autoinc, pbi);
 
       if (GET_CODE (reg) == MEM && ! side_effects_p (reg)
 	  /* ??? With more effort we could track conditional memory life.  */
-	  && ! cond
-	  /* There are no REG_INC notes for SP, so we can't assume we'll see
-	     everything that invalidates it.  To be safe, don't eliminate any
-	     stores though SP; none of them should be redundant anyway.  */
-	  && ! reg_mentioned_p (stack_pointer_rtx, reg))
+	  && ! cond)
         add_to_mem_set_list (pbi, canon_rtx (reg));
     }
 
@@ -3780,7 +3786,7 @@ mark_used_regs (pbi, x, cond, insn)
 	     address modes.  Then we may need to kill some entries on the
 	     memory set list.  */
 	  if (insn)
-	    invalidate_mems_from_autoinc (pbi, insn);
+	    for_each_rtx (&PATTERN (insn), invalidate_mems_from_autoinc, pbi);
 	}
 
 #ifdef AUTO_INC_DEC