2011-07-14  Richard Sandiford  <richard.sandiford@linaro.org>

	Backport from mainline:
	gcc/
	2011-07-07  Richard Sandiford  <richard.sandiford@linaro.org>

	* reload1.c (choose_reload_regs): Use mode sizes to check whether
	an old reload register completely defines the required value.

	gcc/testsuite/
	2011-07-07  Richard Sandiford  <richard.sandiford@linaro.org>

	* gcc.target/arm/neon-modes-3.c: New test.

=== modified file 'gcc/reload1.c'
--- old/gcc/reload1.c	2011-07-01 09:27:50 +0000
+++ new/gcc/reload1.c	2011-07-11 10:05:08 +0000
@@ -6449,6 +6449,8 @@
 
 	      if (regno >= 0
 		  && reg_last_reload_reg[regno] != 0
+		  && (GET_MODE_SIZE (GET_MODE (reg_last_reload_reg[regno]))
+		      >= GET_MODE_SIZE (mode) + byte)
 #ifdef CANNOT_CHANGE_MODE_CLASS
 		  /* Verify that the register it's in can be used in
 		     mode MODE.  */
@@ -6460,24 +6462,12 @@
 		{
 		  enum reg_class rclass = rld[r].rclass, last_class;
 		  rtx last_reg = reg_last_reload_reg[regno];
-		  enum machine_mode need_mode;
 
 		  i = REGNO (last_reg);
 		  i += subreg_regno_offset (i, GET_MODE (last_reg), byte, mode);
 		  last_class = REGNO_REG_CLASS (i);
 
-		  if (byte == 0)
-		    need_mode = mode;
-		  else
-		    need_mode
-		      = smallest_mode_for_size
-		        (GET_MODE_BITSIZE (mode) + byte * BITS_PER_UNIT,
-			 GET_MODE_CLASS (mode) == MODE_PARTIAL_INT
-			 ? MODE_INT : GET_MODE_CLASS (mode));
-
-		  if ((GET_MODE_SIZE (GET_MODE (last_reg))
-		       >= GET_MODE_SIZE (need_mode))
-		      && reg_reloaded_contents[i] == regno
+		  if (reg_reloaded_contents[i] == regno
 		      && TEST_HARD_REG_BIT (reg_reloaded_valid, i)
 		      && HARD_REGNO_MODE_OK (i, rld[r].mode)
 		      && (TEST_HARD_REG_BIT (reg_class_contents[(int) rclass], i)

=== added file 'gcc/testsuite/gcc.target/arm/neon-modes-3.c'
--- old/gcc/testsuite/gcc.target/arm/neon-modes-3.c	1970-01-01 00:00:00 +0000
+++ new/gcc/testsuite/gcc.target/arm/neon-modes-3.c	2011-07-11 10:05:08 +0000
@@ -0,0 +1,61 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target arm_neon_ok } */
+/* { dg-options "-O" } */
+/* { dg-add-options arm_neon } */
+
+#include <arm_neon.h>
+
+void f1 (volatile float32x4_t *dest, volatile float32x4x4_t *src, int n)
+{
+  float32x4x4_t a5, a6, a7, a8, a9;
+  int i;
+
+  a5 = *src;
+  a6 = *src;
+  a7 = *src;
+  a8 = *src;
+  a9 = *src;
+  while (n--)
+    {
+      for (i = 0; i < 8; i++)
+	{
+	  float32x4x4_t a0, a1, a2, a3, a4;
+
+	  a0 = *src;
+	  a1 = *src;
+	  a2 = *src;
+	  a3 = *src;
+	  a4 = *src;
+	  *src = a0;
+	  *dest = a0.val[0];
+	  *dest = a0.val[3];
+	  *src = a1;
+	  *dest = a1.val[0];
+	  *dest = a1.val[3];
+	  *src = a2;
+	  *dest = a2.val[0];
+	  *dest = a2.val[3];
+	  *src = a3;
+	  *dest = a3.val[0];
+	  *dest = a3.val[3];
+	  *src = a4;
+	  *dest = a4.val[0];
+	  *dest = a4.val[3];
+	}
+      *src = a5;
+      *dest = a5.val[0];
+      *dest = a5.val[3];
+      *src = a6;
+      *dest = a6.val[0];
+      *dest = a6.val[3];
+      *src = a7;
+      *dest = a7.val[0];
+      *dest = a7.val[3];
+      *src = a8;
+      *dest = a8.val[0];
+      *dest = a8.val[3];
+      *src = a9;
+      *dest = a9.val[0];
+      *dest = a9.val[3];
+    }
+}