From: Bernd Schmidt <bernds@redhat.co.uk>
Date: Wed, 20 Dec 2000 13:47:24 +0000 (+0000)
Subject: Handle multiword hard regs properly in find_equiv_reg
X-Git-Tag: prereleases/gcc-2.95.3-test1~24
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b1077f68f454e38b818d6b65dd5380b42e75ae62;p=thirdparty%2Fgcc.git

Handle multiword hard regs properly in find_equiv_reg

From-SVN: r38396
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 09a5fad23217..49b0610895a2 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,17 @@
+2000-12-20  Bernd Schmidt  <bernds@redhat.co.uk>
+
+	Thu Nov  2 19:20:12 2000  J"orn Rennecke <amylaar@redhat.com>
+	* reload.c (find_equiv_reg): Test all hard registers for membership
+	in the requested class.
+
+	Sun Apr 23 16:24:35 2000  Denis Chertykov  <denisc@overta.ru>
+	* reload.c (find_equiv_reg): Checks all valueno regs
+	as a reload_reg_p regs.
+
+	Fri Apr 21 14:58:29 2000  Denis Chertykov  <denisc@overta.ru>
+	* reload.c (find_equiv_reg): Checks all valueno and regno regs
+	as a call-clobbered regs.
+
 2000-12-18  Bernd Schmidt  <bernds@redhat.co.uk>
 
 	2000-09-15  Bernd Schmidt  <bernds@redhat.co.uk>
diff --git a/gcc/reload.c b/gcc/reload.c
index 7aa297150e80..5b828670df2f 100644
--- a/gcc/reload.c
+++ b/gcc/reload.c
@@ -6274,16 +6274,29 @@ find_equiv_reg (goal, insn, class, other, reload_reg_p, goalreg, mode)
 		      && (valtry
 			  = operand_subword (SET_DEST (pat), 1, 0, VOIDmode))
 		      && (valueno = true_regnum (valtry)) >= 0)))
-	    if (other >= 0
-		? valueno == other
-		: ((unsigned) valueno < FIRST_PSEUDO_REGISTER
-		   && TEST_HARD_REG_BIT (reg_class_contents[(int) class],
-					 valueno)))
-	      {
-		value = valtry;
-		where = p;
-		break;
-	      }
+	    {
+	      if (other >= 0)
+		{
+		  if (valueno != other)
+		    continue;
+		}
+	      else if ((unsigned) valueno >= FIRST_PSEUDO_REGISTER)
+		continue;
+	      else
+		{
+		  int i;
+
+		  for (i = HARD_REGNO_NREGS (valueno, mode) - 1; i >= 0; i--)
+		    if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class],
+					     valueno + i))
+		      break;
+		  if (i >= 0)
+		    continue;
+		}
+	      value = valtry;
+	      where = p;
+	      break;
+	    }
 	}
     }
 
@@ -6326,15 +6339,22 @@ find_equiv_reg (goal, insn, class, other, reload_reg_p, goalreg, mode)
       && regno < valueno + HARD_REGNO_NREGS (valueno, mode))
     return 0;
 
+  nregs = HARD_REGNO_NREGS (regno, mode);
+  valuenregs = HARD_REGNO_NREGS (valueno, mode);
+
   /* Reject VALUE if it is one of the regs reserved for reloads.
      Reload1 knows how to reuse them anyway, and it would get
      confused if we allocated one without its knowledge.
      (Now that insns introduced by reload are ignored above,
      this case shouldn't happen, but I'm not positive.)  */
 
-  if (reload_reg_p != 0 && reload_reg_p != (short *) (HOST_WIDE_INT) 1
-      && reload_reg_p[valueno] >= 0)
-    return 0;
+  if (reload_reg_p != 0 && reload_reg_p != (short *) (HOST_WIDE_INT) 1)
+    {
+      int i;
+      for (i = 0; i < valuenregs; ++i)
+	if (reload_reg_p[valueno + i] >= 0)
+	  return 0;
+    }
 
   /* On some machines, certain regs must always be rejected
      because they don't behave the way ordinary registers do.  */
@@ -6344,9 +6364,6 @@ find_equiv_reg (goal, insn, class, other, reload_reg_p, goalreg, mode)
     return 0;
 #endif      
 
-  nregs = HARD_REGNO_NREGS (regno, mode);
-  valuenregs = HARD_REGNO_NREGS (valueno, mode);
-
   /* Reject VALUE if it is a register being used for an input reload
      even if it is not one of those reserved.  */
 
@@ -6382,16 +6399,23 @@ find_equiv_reg (goal, insn, class, other, reload_reg_p, goalreg, mode)
 
       /* Don't trust the conversion past a function call
 	 if either of the two is in a call-clobbered register, or memory.  */
-      if (GET_CODE (p) == CALL_INSN
-	  && ((regno >= 0 && regno < FIRST_PSEUDO_REGISTER
-	       && call_used_regs[regno])
-	      ||
-	      (valueno >= 0 && valueno < FIRST_PSEUDO_REGISTER
-	       && call_used_regs[valueno])
-	      ||
-	      goal_mem
-	      || need_stable_sp))
-	return 0;
+      if (GET_CODE (p) == CALL_INSN)
+	{
+	  int i;
+
+	  if (goal_mem || need_stable_sp)
+	    return 0;
+
+	  if (regno >= 0 && regno < FIRST_PSEUDO_REGISTER)
+	    for (i = 0; i < nregs; ++i)
+	      if (call_used_regs[regno + i])
+		return 0;
+
+	  if (valueno >= 0 && valueno < FIRST_PSEUDO_REGISTER)
+	    for (i = 0; i < valuenregs; ++i)
+	      if (call_used_regs[valueno + i])
+		return 0;
+	}
 
 #ifdef NON_SAVING_SETJMP 
       if (NON_SAVING_SETJMP && GET_CODE (p) == NOTE