Enlist the FreeBSD-CURRENT users as testers of GCC 2.95.3 Release Candidate #1

1 files changed, 18 insertions, 18 deletions

diff --git a/contrib/gcc/emit-rtl.c b/contrib/gcc/emit-rtl.c
index 36b030a..54cee16 100644
--- a/contrib/gcc/emit-rtl.c
+++ b/contrib/gcc/emit-rtl.c
@@ -1847,25 +1847,17 @@ copy_rtx_if_shared (orig)
       return x;
 
     case MEM:
-      /* A MEM is allowed to be shared if its address is constant
-	 or is a constant plus one of the special registers.  */
-      if (CONSTANT_ADDRESS_P (XEXP (x, 0))
-	  || XEXP (x, 0) == virtual_stack_vars_rtx
-	  || XEXP (x, 0) == virtual_incoming_args_rtx)
+      /* A MEM is allowed to be shared if its address is constant.
+
+	 We used to allow sharing of MEMs which referenced 
+	 virtual_stack_vars_rtx or virtual_incoming_args_rtx, but
+	 that can lose.  instantiate_virtual_regs will not unshare
+	 the MEMs, and combine may change the structure of the address
+	 because it looks safe and profitable in one context, but
+	 in some other context it creates unrecognizable RTL.  */
+      if (CONSTANT_ADDRESS_P (XEXP (x, 0)))
 	return x;
 
-      if (GET_CODE (XEXP (x, 0)) == PLUS
-	  && (XEXP (XEXP (x, 0), 0) == virtual_stack_vars_rtx
-	      || XEXP (XEXP (x, 0), 0) == virtual_incoming_args_rtx)
-	  && CONSTANT_ADDRESS_P (XEXP (XEXP (x, 0), 1)))
-	{
-	  /* This MEM can appear in more than one place,
-	     but its address better not be shared with anything else.  */
-	  if (! x->used)
-	    XEXP (x, 0) = copy_rtx_if_shared (XEXP (x, 0));
-	  x->used = 1;
-	  return x;
-	}
       break;
 
     default:
@@ -2359,10 +2351,18 @@ try_split (pat, trial, last)
 	 it, in turn, will be split (SFmode on the 29k is an example).  */
       if (GET_CODE (seq) == SEQUENCE)
 	{
+	  int i;
+
+	  /* Avoid infinite loop if any insn of the result matches 
+	     the original pattern.  */
+	  for (i = 0; i < XVECLEN (seq, 0); i++)
+  	    if (GET_CODE (XVECEXP (seq, 0, i)) == INSN 
+		&& rtx_equal_p (PATTERN (XVECEXP (seq, 0, i)), pat))
+  	      return trial;
+
 	  /* If we are splitting a JUMP_INSN, look for the JUMP_INSN in
 	     SEQ and copy our JUMP_LABEL to it.  If JUMP_LABEL is non-zero,
 	     increment the usage count so we don't delete the label.  */
-	  int i;
 
 	  if (GET_CODE (trial) == JUMP_INSN)
 	    for (i = XVECLEN (seq, 0) - 1; i >= 0; i--)