expmed.c (store_bit_field): Handle paradoxical subregs on big endian machines.

2006-04-25  Andreas Krebbel  <krebbel1@de.ibm.com>

	* expmed.c (store_bit_field): Handle paradoxical subregs on big endian
	machines.

2006-04-25  Andreas Krebbel  <krebbel1@de.ibm.com>

	* gcc.dg/20060425-1.c: New testcase.

From-SVN: r113248

gcc/ChangeLog

+2006-04-25  Andreas Krebbel  <krebbel1@de.ibm.com>
+
+	* expmed.c (store_bit_field): Handle paradoxical subregs on big endian
+	machines.
+
 2006-04-25  Bernd Schmidt  <bernd.schmidt@analog.com>
 
 	* genmodes.c (make_vector_mode): Allow making VECTOR_MODE_INT of a

gcc/expmed.c

@@ -363,7 +363,25 @@ store_bit_field (rtx str_rtx, unsigned HOST_WIDE_INT bitsize,
 	 meaningful at a much higher level; when structures are copied
 	 between memory and regs, the higher-numbered regs
 	 always get higher addresses.  */
-      bitnum += SUBREG_BYTE (op0) * BITS_PER_UNIT;
+      int inner_mode_size = GET_MODE_SIZE (GET_MODE (SUBREG_REG (op0)));
+      int outer_mode_size = GET_MODE_SIZE (GET_MODE (op0));
+      
+      byte_offset = 0;
+
+      /* Paradoxical subregs need special handling on big endian machines.  */
+      if (SUBREG_BYTE (op0) == 0 && inner_mode_size < outer_mode_size)
+	{
+	  int difference = inner_mode_size - outer_mode_size;
+
+	  if (WORDS_BIG_ENDIAN)
+	    byte_offset += (difference / UNITS_PER_WORD) * UNITS_PER_WORD;
+	  if (BYTES_BIG_ENDIAN)
+	    byte_offset += difference % UNITS_PER_WORD;
+	}
+      else
+	byte_offset = SUBREG_BYTE (op0);
+
+      bitnum += byte_offset * BITS_PER_UNIT;
       op0 = SUBREG_REG (op0);
     }
 

gcc/testsuite/ChangeLog

+2006-04-25  Andreas Krebbel  <krebbel1@de.ibm.com>
+
+	* gcc.dg/20060425-1.c: New testcase.
+
 2006-04-25  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/26865

gcc/testsuite/gcc.dg/20060425-1.c

+/* { dg-do run } */
+/* { dg-options "-O1" } */
+
+/* This failed because if conversion didn't handle insv patterns properly.  */
+
+void abort (void);
+
+union y
+{
+  int a;
+  unsigned short b;
+};
+
+void __attribute__ ((noinline))
+bar (unsigned short u, union y v)
+{
+  if (u != 1)
+    abort ();
+}
+
+void __attribute__ ((noinline))
+foo (int check)
+{
+  union y x;
+
+  if (check != 0)
+    x.b = 1;
+  else
+    x.b = 2;
+  bar (x.b, x);
+}
+
+int
+main ()
+{
+  foo (1);
+  return 0;
+}