From: Bernd Schmidt <bernds@redhat.co.uk>
Date: Thu, 30 Nov 2000 12:28:02 +0000 (+0000)
Subject: Backport a change to the 2.95 branch
X-Git-Tag: prereleases/gcc-2.95.3-test1~46
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3f3fdff8fb3017383c2e275effac90687e673576;p=thirdparty%2Fgcc.git

Backport a change to the 2.95 branch

From-SVN: r37887
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 16dde7299e9e..2924f0daf97a 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,13 @@
 2000-11-30  Bernd Schmidt  <bernds@redhat.co.uk>
 
+	Wed Oct 27 03:09:23 1999  J"orn Rennecke  <amylaar@redhat.co.uk>
+	* reload.h (earlyclobber_operand_p): Declare.
+	* reload.c (earlyclobber_operand_p): Don't declare.  No longer static.
+	* reload1.c (reload_reg_free_for_value_p):  RELOAD_OTHER reloads with
+	an earlyclobbered output conflict with RELOAD_INPUT reloads - handle
+	case where the RELOAD_OTHER reload is new.  Use
+	earlyclobber_operand_p.
+
 	2000-01-12  Bernd Schmidt  <bernds@redhat.co.uk>
 	* reload1.c (reload_reg_unavailable): New static variable.
 	(reload_reg_free_p): Test it.
diff --git a/gcc/reload.c b/gcc/reload.c
index 689acaa2ec3c..72b38f325165 100644
--- a/gcc/reload.c
+++ b/gcc/reload.c
@@ -322,7 +322,6 @@ static int find_reusable_reload	PROTO((rtx *, rtx, enum reg_class,
 static rtx find_dummy_reload	PROTO((rtx, rtx, rtx *, rtx *,
 				       enum machine_mode, enum machine_mode,
 				       enum reg_class, int, int));
-static int earlyclobber_operand_p PROTO((rtx));
 static int hard_reg_set_here_p	PROTO((int, int, rtx));
 static struct decomposition decompose PROTO((rtx));
 static int immune_p		PROTO((rtx, rtx, struct decomposition));
@@ -2006,7 +2005,7 @@ find_dummy_reload (real_in, real_out, inloc, outloc,
 
 /* Return 1 if X is an operand of an insn that is being earlyclobbered.  */
 
-static int
+int
 earlyclobber_operand_p (x)
      rtx x;
 {
diff --git a/gcc/reload.h b/gcc/reload.h
index 968d3124af49..50526db8566f 100644
--- a/gcc/reload.h
+++ b/gcc/reload.h
@@ -342,3 +342,5 @@ extern void save_call_clobbered_regs PROTO((void));
 
 /* Replace (subreg (reg)) with the appropriate (reg) for any operands.  */
 extern void cleanup_subreg_operands PROTO ((rtx));
+
+extern int earlyclobber_operand_p PROTO((rtx));
diff --git a/gcc/reload1.c b/gcc/reload1.c
index b49d9925551f..82c7cbe4b5c9 100644
--- a/gcc/reload1.c
+++ b/gcc/reload1.c
@@ -5206,6 +5206,10 @@ reload_reg_free_for_value_p (regno, opnum, type, value, out, reloadnum,
      int ignore_address_reloads;
 {
   int time1;
+  /* Set if we see an input reload that must not share its reload register
+     with any new earlyclobber, but might otherwise share the reload
+     register with an output or input-output reload.  */
+  int check_earlyclobber = 0;
   int i;
   int copy = 0;
 
@@ -5333,6 +5337,7 @@ reload_reg_free_for_value_p (regno, opnum, type, value, out, reloadnum,
 		  break;
 		case RELOAD_FOR_INPUT:
 		  time2 = reload_opnum[i] * 4 + 4;
+		  check_earlyclobber = 1;
 		  break;
 		/* reload_opnum[i] * 4 + 4 <= (MAX_RECOG_OPERAND - 1) * 4 + 4
 		   == MAX_RECOG_OPERAND * 4  */
@@ -5345,6 +5350,7 @@ reload_reg_free_for_value_p (regno, opnum, type, value, out, reloadnum,
 		  break;
 		case RELOAD_FOR_OPERAND_ADDRESS:
 		  time2 = MAX_RECOG_OPERANDS * 4 + 2;
+		  check_earlyclobber = 1;
 		  break;
 		case RELOAD_FOR_INSN:
 		  time2 = MAX_RECOG_OPERANDS * 4 + 3;
@@ -5373,6 +5379,9 @@ reload_reg_free_for_value_p (regno, opnum, type, value, out, reloadnum,
 		  if (! reload_in[i] || rtx_equal_p (reload_in[i], value))
 		    {
 		      time2 = MAX_RECOG_OPERANDS * 4 + 4;
+		      /* Earlyclobbered outputs must conflict with inputs.  */
+		      if (earlyclobber_operand_p (reload_out[i]))
+			time2 = MAX_RECOG_OPERANDS * 4 + 3;
 		      break;
 		    }
 		  time2 = 1;
@@ -5395,6 +5404,11 @@ reload_reg_free_for_value_p (regno, opnum, type, value, out, reloadnum,
 	    }
 	}
     }
+
+  /* Earlyclobbered outputs must conflict with inputs.  */
+  if (check_earlyclobber && out && earlyclobber_operand_p (out))
+    return 0;
+
   return 1;
 }