gcse.c (gcse_constant_p): COMPARE of the same registers is a constant if...

2003-05-02	Andrew Pinski <pinskia@physics.uc.edu>

	* gcse.c (gcse_constant_p): COMPARE of the same registers is a constant
	if they are not floating point registers.

From-SVN: r69471

gcc/ChangeLog

 2003-07-16  Andrew Pinski  <pinskia@physics.uc.edu>
 
+	* gcse.c (gcse_constant_p): COMPARE of the same registers is a constant
+	if they are not floating point registers.
+
+2003-07-16  Andrew Pinski  <pinskia@physics.uc.edu>
+
 	PR c/10962
 	* ggc.h: Add header guards.
 	* c-decl.c (finish_struct): Sort fields if

gcc/gcse.c

@@ -2123,6 +2123,17 @@ gcse_constant_p (rtx x)
       && GET_CODE (XEXP (x, 1)) == CONST_INT)
     return true;
 
+
+  /* Consider a COMPARE of the same registers is a constant
+    if they are not floating point registers. */
+  if (GET_CODE(x) == COMPARE
+      && GET_CODE (XEXP (x, 0)) == REG
+      && GET_CODE (XEXP (x, 1)) == REG
+      && REGNO (XEXP (x, 0)) == REGNO (XEXP (x, 1))
+      && ! FLOAT_MODE_P (GET_MODE (XEXP (x, 0)))
+      && ! FLOAT_MODE_P (GET_MODE (XEXP (x, 1))))
+    return true;
+
   if (GET_CODE (x) == CONSTANT_P_RTX)
     return false;