re PR target/13889 (Assignment of an int to an int of different size in a struct gives ICE)

	PR target/13889
	* cse.c (fold_rtx): Avoid substituting constants into unary
	convertion operations.

	* gcc.c-torture/compile/pr13889.c: New test case.

From-SVN: r79762

gcc/ChangeLog

+2004-03-20  Roger Sayle  <roger@eyesopen.com>
+
+	PR target/13889
+	* cse.c (fold_rtx): Avoid substituting constants into unary
+	convertion operations.
+
 2004-03-20  Kazu Hirata  <kazu@cs.umass.edu>
 
 	* fold-const.c (fold): Replace "expr" with "t".

gcc/cse.c

@@ -3662,6 +3662,23 @@ fold_rtx (rtx x, rtx insn)
 		|| (new_cost == old_cost && CONSTANT_P (XEXP (x, i))))
 	      break;
 
+	    /* It's not safe to substitute the operand of a conversion
+	       operator with a constant, as the conversion's identity
+	       depends upon the mode of it's operand.  This optimization
+	       is handled by the call to simplify_unary_operation.  */
+	    if (GET_RTX_CLASS (code) == RTX_UNARY
+		&& GET_MODE (replacements[j]) != mode_arg0
+		&& (code == ZERO_EXTEND
+		    || code == SIGN_EXTEND
+		    || code == TRUNCATE
+		    || code == FLOAT_TRUNCATE
+		    || code == FLOAT_EXTEND
+		    || code == FLOAT
+		    || code == FIX
+		    || code == UNSIGNED_FLOAT
+		    || code == UNSIGNED_FIX))
+	      continue;
+
 	    if (validate_change (insn, &XEXP (x, i), replacements[j], 0))
 	      break;
 

gcc/testsuite/ChangeLog

+2004-03-20  Roger Sayle  <roger@eyesopen.com>
+
+	PR target/13889
+	* gcc.c-torture/compile/pr13889.c: New test case.
+
 2004-03-20  Joseph S. Myers  <jsm@polyomino.org.uk>
 
 	PR c/14635

gcc/testsuite/gcc.c-torture/compile/pr13889.c

+/* PR target/13889 */
+struct { long long a; } *p;
+void initNetFlowFunct(void) {
+  unsigned int b = (unsigned int)-1;
+  p->a = b;
+}
+