diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 74482ede3af..ed624bb35f5 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2011-09-22  Richard Sandiford  <rdsandiford@googlemail.com>
+
+	PR middle-end/50113
+	PR middle-end/50061
+	* calls.c (emit_library_call_value_1): Use BLOCK_REG_PADDING to
+	get the locate.where_pad value for register-only arguments.
+	* config/arm/arm.c (arm_pad_arg_upward): Remove HFmode handling.
+	(arm_pad_reg_upward): Handle null types.
+
 2011-09-22  Jan Hubicka  <jh@suse.cz>
 
 	* ipa-inline-analysis.c: Fix overly long lines.
diff --git a/gcc/calls.c b/gcc/calls.c
index 1413c8d9dd6..3fa70b571f4 100644
--- a/gcc/calls.c
+++ b/gcc/calls.c
@@ -3577,20 +3577,29 @@ emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
       argvec[count].partial
 	= targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
 
-      locate_and_pad_parm (mode, NULL_TREE,
-#ifdef STACK_PARMS_IN_REG_PARM_AREA
-			   1,
-#else
-			   argvec[count].reg != 0,
-#endif
-			   argvec[count].partial,
-			   NULL_TREE, &args_size, &argvec[count].locate);
-
-      gcc_assert (!argvec[count].locate.size.var);
-
-      if (argvec[count].reg == 0 || argvec[count].partial != 0
+      if (argvec[count].reg == 0
+	  || argvec[count].partial != 0
 	  || reg_parm_stack_space > 0)
-	args_size.constant += argvec[count].locate.size.constant;
+	{
+	  locate_and_pad_parm (mode, NULL_TREE,
+#ifdef STACK_PARMS_IN_REG_PARM_AREA
+			       1,
+#else
+			       argvec[count].reg != 0,
+#endif
+			       argvec[count].partial,
+			       NULL_TREE, &args_size, &argvec[count].locate);
+	  args_size.constant += argvec[count].locate.size.constant;
+	  gcc_assert (!argvec[count].locate.size.var);
+	}
+#ifdef BLOCK_REG_PADDING
+      else
+	/* The argument is passed entirely in registers.  See at which
+	   end it should be padded.  */
+	argvec[count].locate.where_pad =
+	  BLOCK_REG_PADDING (mode, NULL_TREE,
+			     GET_MODE_SIZE (mode) <= UNITS_PER_WORD);
+#endif
 
       targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
     }
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index b45f9392e2f..e730881f40b 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -11573,7 +11573,7 @@ arm_must_pass_in_stack (enum machine_mode mode, const_tree type)
    aggregate types are placed in the lowest memory address.  */
 
 bool
-arm_pad_arg_upward (enum machine_mode mode, const_tree type)
+arm_pad_arg_upward (enum machine_mode mode ATTRIBUTE_UNUSED, const_tree type)
 {
   if (!TARGET_AAPCS_BASED)
     return DEFAULT_FUNCTION_ARG_PADDING(mode, type) == upward;
@@ -11581,36 +11581,38 @@ arm_pad_arg_upward (enum machine_mode mode, const_tree type)
   if (type && BYTES_BIG_ENDIAN && INTEGRAL_TYPE_P (type))
     return false;
 
-  /* Half-float values are only passed to libcalls, not regular functions.
-     They should be passed and returned as "short"s (see RTABI).  To achieve
-     that effect in big-endian mode, pad downwards so the value is passed in
-     the least-significant end of the register.  ??? This needs to be here
-     rather than in arm_pad_reg_upward due to peculiarity in the handling of
-     libcall arguments.  */
-  if (BYTES_BIG_ENDIAN && mode == HFmode)
-    return false;
-
   return true;
 }
 
 
 /* Similarly, for use by BLOCK_REG_PADDING (MODE, TYPE, FIRST).
-   For non-AAPCS, return !BYTES_BIG_ENDIAN if the least significant
-   byte of the register has useful data, and return the opposite if the
-   most significant byte does.
-   For AAPCS, small aggregates and small complex types are always padded
-   upwards.  */
+   Return !BYTES_BIG_ENDIAN if the least significant byte of the
+   register has useful data, and return the opposite if the most
+   significant byte does.  */
 
 bool
-arm_pad_reg_upward (enum machine_mode mode ATTRIBUTE_UNUSED,
+arm_pad_reg_upward (enum machine_mode mode,
                     tree type, int first ATTRIBUTE_UNUSED)
 {
-  if (TARGET_AAPCS_BASED
-      && BYTES_BIG_ENDIAN
-      && (AGGREGATE_TYPE_P (type) || TREE_CODE (type) == COMPLEX_TYPE
-	  || FIXED_POINT_TYPE_P (type))
-      && int_size_in_bytes (type) <= 4)
-    return true;
+  if (TARGET_AAPCS_BASED && BYTES_BIG_ENDIAN)
+    {
+      /* For AAPCS, small aggregates, small fixed-point types,
+	 and small complex types are always padded upwards.  */
+      if (type)
+	{
+	  if ((AGGREGATE_TYPE_P (type)
+	       || TREE_CODE (type) == COMPLEX_TYPE
+	       || FIXED_POINT_TYPE_P (type))
+	      && int_size_in_bytes (type) <= 4)
+	    return true;
+	}
+      else
+	{
+	  if ((COMPLEX_MODE_P (mode) || ALL_FIXED_POINT_MODE_P (mode))
+	      && GET_MODE_SIZE (mode) <= 4)
+	    return true;
+	}
+    }
 
   /* Otherwise, use default padding.  */
   return !BYTES_BIG_ENDIAN;