cse.c (fold_rtx): Don't optimize if SUBREG changes mode class.

	* cse.c (fold_rtx): Don't optimize if SUBREG changes mode class.

	* g++.dg/opt/cse2.C: New test.

From-SVN: r53905

gcc/ChangeLog

+2002-05-26  Jakub Jelinek  <jakub@redhat.com>
+
+	* cse.c (fold_rtx): Don't optimize if SUBREG changes mode class.
+
 2002-05-26  Andreas Jaeger  <aj@suse.de>
 
 	* cfg.c (dump_flow_info): Remove extra argument to fprintf.

gcc/cse.c

@@ -3472,7 +3472,9 @@ fold_rtx (x, insn)
 		  && GET_CODE (elt->exp) != SIGN_EXTEND
 		  && GET_CODE (elt->exp) != ZERO_EXTEND
 		  && GET_CODE (XEXP (elt->exp, 0)) == SUBREG
-		  && GET_MODE (SUBREG_REG (XEXP (elt->exp, 0))) == mode)
+		  && GET_MODE (SUBREG_REG (XEXP (elt->exp, 0))) == mode
+		  && (GET_MODE_CLASS (mode)
+		      == GET_MODE_CLASS (GET_MODE (XEXP (elt->exp, 0)))))
 		{
 		  rtx op0 = SUBREG_REG (XEXP (elt->exp, 0));
 

gcc/testsuite/ChangeLog

+2002-05-26  Jakub Jelinek  <jakub@redhat.com>
+
+	* g++.dg/opt/cse2.C: New test.
+
 2002-05-26  Neil Booth  <neil@daikokuya.demon.co.uk>
 
 	* gcc.dg/cpp/arith-1.c: New semantic tests.

gcc/testsuite/g++.dg/opt/cse2.C

+// This testcase caused ICE on IA-32 in simplify_unary_operation
+// CSE did not assume SUBREGs changing mode from integral to floating.
+// { dg-do run { target i?86-*-* sparc*-*-* } }
+// { dg-options "-O2" }
+
+struct A
+{
+  union
+    {
+      float f;
+      unsigned int w;
+    } a;
+
+  static inline const A foo (void)
+    {
+      return A ((unsigned int) (__extension__ ((union { unsigned l; float d; })
+					       { l: 0x3f800000 }).d));
+    }
+  inline A (float f) { a.f = f; }
+  A ();
+  inline A (unsigned int w) { a.w = w; }
+};
+
+A::A()
+{
+  *this = foo ();
+}
+
+A a;
+
+extern "C" void abort (void);
+extern "C" void exit (int);
+
+int main ()
+{
+  if (a.a.w != 1)
+    abort ();
+  exit (0);
+}