Gimplify VA_ARG_EXPR into simpler forms.

        * target.h: Add gimplify_va_arg_expr hook.
        * target-def.h: Add TARGET_GIMPLIFY_VA_ARG_EXPR.
        * fold-const.c (build_fold_addr_expr)
        (build_fold_addr_expr_with_type): Move from gimplify.c.
        * tree.h: Declare them.
        * gimplify.c (gimplify_and_add): New fn.
        (build_addr_expr, build_addr_expr_with_type): Move to fold-const.c.
        (gimplify_array_ref_to_plus, gimplify_modify_expr)
        (gimplify_expr): Use build_fold_*.
        (copy_if_shared_r): Only mark VA_ARG_EXPR volatile if we
        don't know how to gimplify it.
        * builtins.c (std_gimplify_va_arg_expr): New fn.
        (dummy_object): New static fn.
        (gimplify_va_arg_expr): New fn.
        (stabilize_va_list): Use build_fold_*.
        * tree-gimple.h: Declare new fns.
        * config/i386/i386.c (TARGET_GIMPLIFY_VA_ARG_EXPR): Define.
        (ix86_gimplify_va_arg): New fn.
        * config/i386/ia64.c (TARGET_GIMPLIFY_VA_ARG_EXPR): Define.
        (ia64_gimplify_va_arg): New fn.
        * config/i386/rs6000.c (rs6000_gimplify_va_arg): New fn.
        (TARGET_GIMPLIFY_VA_ARG_EXPR): Define.
        * config/i386/sparc.c (sparc_gimplify_va_arg): New fn.
        * alias.c (get_varargs_alias_set): Just return 0 for now.

        * c-objc-common.c (c_tree_printer): Improve handling of %T.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@82838 138bc75d-0d04-0410-961f-82ee72b054a4

13 files changed, 869 insertions, 60 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a19dcb2da21..1793e5c590e 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,33 @@
+2004-06-08  Jason Merrill  <jason@redhat.com>
+
+	Gimplify VA_ARG_EXPR into simpler forms.
+	* target.h: Add gimplify_va_arg_expr hook.
+	* target-def.h: Add TARGET_GIMPLIFY_VA_ARG_EXPR.
+	* fold-const.c (build_fold_addr_expr)
+	(build_fold_addr_expr_with_type): Move from gimplify.c.
+	* tree.h: Declare them.
+	* gimplify.c (gimplify_and_add): New fn.
+	(build_addr_expr, build_addr_expr_with_type): Move to fold-const.c.
+	(gimplify_array_ref_to_plus, gimplify_modify_expr)
+	(gimplify_expr): Use build_fold_*.
+	(copy_if_shared_r): Only mark VA_ARG_EXPR volatile if we
+	don't know how to gimplify it.
+	* builtins.c (std_gimplify_va_arg_expr): New fn.
+	(dummy_object): New static fn.
+	(gimplify_va_arg_expr): New fn.
+	(stabilize_va_list): Use build_fold_*.
+	* tree-gimple.h: Declare new fns.
+	* config/i386/i386.c (TARGET_GIMPLIFY_VA_ARG_EXPR): Define.
+	(ix86_gimplify_va_arg): New fn.
+	* config/i386/ia64.c (TARGET_GIMPLIFY_VA_ARG_EXPR): Define.
+	(ia64_gimplify_va_arg): New fn.
+	* config/i386/rs6000.c (rs6000_gimplify_va_arg): New fn.
+	(TARGET_GIMPLIFY_VA_ARG_EXPR): Define.
+	* config/i386/sparc.c (sparc_gimplify_va_arg): New fn.
+	* alias.c (get_varargs_alias_set): Just return 0 for now.
+	
+	* c-objc-common.c (c_tree_printer): Improve handling of %T.
+
 2004-06-09  Andrew Pinski  <pinskia@physics.uc.edu>
 
 	* tree-complex.c (expand_complex_comparison): Use fold_convert instead
diff --git a/gcc/alias.c b/gcc/alias.c
index e41e456892a..3e2bbbbad5d 100644
--- a/gcc/alias.c
+++ b/gcc/alias.c
@@ -737,10 +737,18 @@ static GTY(()) HOST_WIDE_INT varargs_set = -1;
 HOST_WIDE_INT
 get_varargs_alias_set (void)
 {
+#if 1
+  /* We now lower VA_ARG_EXPR, and there's currently no way to attach the
+     varargs alias set to an INDIRECT_REF (FIXME!), so we can't
+     consistently use the varargs alias set for loads from the varargs
+     area.  So don't use it anywhere.  */
+  return 0;
+#else
   if (varargs_set == -1)
     varargs_set = new_alias_set ();
 
   return varargs_set;
+#endif
 }
 
 /* Likewise, but used for the fixed portions of the frame, e.g., register
diff --git a/gcc/builtins.c b/gcc/builtins.c
index d10924f7919..9816af0817c 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -4106,10 +4106,7 @@ stabilize_va_list (tree valist, int needs_lvalue)
       if (TREE_CODE (TREE_TYPE (valist)) == ARRAY_TYPE)
 	{
 	  tree p1 = build_pointer_type (TREE_TYPE (va_list_type_node));
-	  tree p2 = build_pointer_type (va_list_type_node);
-
-	  valist = build1 (ADDR_EXPR, p2, valist);
-	  valist = fold_convert (p1, valist);
+	  valist = build_fold_addr_expr_with_type (valist, p1);
 	}
     }
   else
@@ -4128,8 +4125,7 @@ stabilize_va_list (tree valist, int needs_lvalue)
 
       if (TREE_SIDE_EFFECTS (valist))
 	valist = save_expr (valist);
-      valist = fold (build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (valist)),
-			     valist));
+      valist = build_fold_indirect_ref (valist);
     }
 
   return valist;
@@ -4364,6 +4360,184 @@ expand_builtin_va_arg (tree valist, tree type)
   return result;
 }
 
+/* Like std_expand_builtin_va_arg, but gimplify instead of expanding.  */
+
+void
+std_gimplify_va_arg_expr (tree *expr_p, tree *pre_p, tree *post_p)
+{
+  tree addr, t, type_size = NULL;
+  tree align, alignm1;
+  tree rounded_size;
+  HOST_WIDE_INT boundary;
+  tree valist = TREE_OPERAND (*expr_p, 0);
+  tree type = TREE_TYPE (*expr_p);
+
+  /* Compute the rounded size of the type.  */
+  align = size_int (PARM_BOUNDARY / BITS_PER_UNIT);
+  alignm1 = size_int (PARM_BOUNDARY / BITS_PER_UNIT - 1);
+  boundary = FUNCTION_ARG_BOUNDARY (TYPE_MODE (type), type);
+
+  /* Reduce valist it so it's sharable with the postqueue.  */
+  gimplify_expr (&valist, pre_p, post_p, is_gimple_min_lval, fb_lvalue);
+
+  /* va_list pointer is aligned to PARM_BOUNDARY.  If argument actually
+     requires greater alignment, we must perform dynamic alignment.  */
+
+  if (boundary > PARM_BOUNDARY)
+    {
+      if (!PAD_VARARGS_DOWN)
+	{
+	  t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist,
+		      build2 (PLUS_EXPR, TREE_TYPE (valist), valist,
+			      build_int_2 (boundary / BITS_PER_UNIT - 1, 0)));
+	  gimplify_stmt (&t);
+	  append_to_statement_list (t, pre_p);
+	}
+      t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist,
+		  build2 (BIT_AND_EXPR, TREE_TYPE (valist), valist,
+			  build_int_2 (~(boundary / BITS_PER_UNIT - 1), -1)));
+      gimplify_stmt (&t);
+      append_to_statement_list (t, pre_p);
+    }
+  if (type == error_mark_node
+      || (type_size = TYPE_SIZE_UNIT (TYPE_MAIN_VARIANT (type))) == NULL
+      || TREE_OVERFLOW (type_size))
+    rounded_size = size_zero_node;
+  else
+    {
+      rounded_size = fold (build2 (PLUS_EXPR, sizetype, type_size, alignm1));
+      rounded_size = fold (build2 (TRUNC_DIV_EXPR, sizetype,
+				   rounded_size, align));
+      rounded_size = fold (build2 (MULT_EXPR, sizetype,
+				   rounded_size, align));
+    }
+
+  /* Reduce rounded_size so it's sharable with the postqueue.  */
+  gimplify_expr (&rounded_size, pre_p, post_p, is_gimple_val, fb_rvalue);
+
+  /* Get AP.  */
+  addr = valist;
+  if (PAD_VARARGS_DOWN && ! integer_zerop (rounded_size))
+    {
+      /* Small args are padded downward.  */
+      addr = fold (build2 (PLUS_EXPR, TREE_TYPE (addr), addr,
+				fold (build3 (COND_EXPR, sizetype,
+					      fold (build2 (GT_EXPR, sizetype,
+							    rounded_size,
+							    align)),
+					      size_zero_node,
+					      fold (build2 (MINUS_EXPR,
+							    sizetype,
+							    rounded_size,
+							    type_size))))));
+    }
+
+  addr = convert (build_pointer_type (type), addr);
+  *expr_p = build1 (INDIRECT_REF, type, addr);
+
+  /* Compute new value for AP.  */
+  if (! integer_zerop (rounded_size))
+    {
+      t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist,
+		  build2 (PLUS_EXPR, TREE_TYPE (valist), valist,
+			  rounded_size));
+      gimplify_stmt (&t);
+      append_to_statement_list (t, post_p);
+    }
+}
+
+/* Return a dummy expression of type TYPE in order to keep going after an
+   error.  */
+
+static tree
+dummy_object (tree type)
+{
+  tree t = convert (build_pointer_type (type), null_pointer_node);
+  return build1 (INDIRECT_REF, type, t);
+}
+
+/* Like expand_builtin_va_arg, but gimplify instead of expanding.  */
+
+enum gimplify_status
+gimplify_va_arg_expr (tree *expr_p, tree *pre_p, tree *post_p)
+{
+  tree promoted_type, want_va_type, have_va_type;
+  tree valist = TREE_OPERAND (*expr_p, 0);
+  tree type = TREE_TYPE (*expr_p);
+  tree t;
+
+  /* Verify that valist is of the proper type.  */
+
+  want_va_type = va_list_type_node;
+  have_va_type = TREE_TYPE (valist);
+  if (TREE_CODE (want_va_type) == ARRAY_TYPE)
+    {
+      /* If va_list is an array type, the argument may have decayed
+	 to a pointer type, e.g. by being passed to another function.
+         In that case, unwrap both types so that we can compare the
+	 underlying records.  */
+      if (TREE_CODE (have_va_type) == ARRAY_TYPE
+	  || TREE_CODE (have_va_type) == POINTER_TYPE)
+	{
+	  want_va_type = TREE_TYPE (want_va_type);
+	  have_va_type = TREE_TYPE (have_va_type);
+	}
+    }
+
+  if (TYPE_MAIN_VARIANT (want_va_type) != TYPE_MAIN_VARIANT (have_va_type))
+    {
+      error ("first argument to `va_arg' not of type `va_list'");
+      *expr_p = dummy_object (type);
+      return GS_ALL_DONE;
+    }
+
+  /* Generate a diagnostic for requesting data of a type that cannot
+     be passed through `...' due to type promotion at the call site.  */
+  else if ((promoted_type = lang_hooks.types.type_promotes_to (type))
+	   != type)
+    {
+      static bool gave_help;
+
+      /* Unfortunately, this is merely undefined, rather than a constraint
+	 violation, so we cannot make this an error.  If this call is never
+	 executed, the program is still strictly conforming.  */
+      warning ("`%T' is promoted to `%T' when passed through `...'",
+	       type, promoted_type);
+      if (! gave_help)
+	{
+	  gave_help = true;
+	  warning ("(so you should pass `%T' not `%T' to `va_arg')",
+		   promoted_type, type);
+	}
+
+      /* We can, however, treat "undefined" any way we please.
+	 Call abort to encourage the user to fix the program.  */
+      inform ("if this code is reached, the program will abort");
+      t = build_function_call_expr (implicit_built_in_decls[BUILT_IN_TRAP],
+				    NULL);
+      append_to_statement_list (t, pre_p);
+
+      /* This is dead code, but go ahead and finish so that the
+	 mode of the result comes out right.  */
+      *expr_p = dummy_object (type);
+      return GS_ALL_DONE;
+    }
+  else
+    {
+      /* Make it easier for the backends by protecting the valist argument
+         from multiple evaluations.  */
+      valist = stabilize_va_list (valist, 0);
+      TREE_OPERAND (*expr_p, 0) = valist;
+
+      if (!targetm.calls.gimplify_va_arg_expr)
+	/* Once most targets are converted this should abort.  */
+	return GS_ALL_DONE;
+
+      targetm.calls.gimplify_va_arg_expr (expr_p, pre_p, post_p);
+      return GS_OK;
+    }
+}
+
 /* Expand ARGLIST, from a call to __builtin_va_end.  */
 
 static rtx
diff --git a/gcc/c-objc-common.c b/gcc/c-objc-common.c
index 6b17ad4e690..f32bf6d8fe0 100644
--- a/gcc/c-objc-common.c
+++ b/gcc/c-objc-common.c
@@ -270,17 +270,15 @@ c_tree_printer (pretty_printer *pp, text_info *text)
       break;
 
     case 'T':
-      if (TREE_CODE (t) == TYPE_DECL)
+      if (TYPE_P (t))
+	t = TYPE_NAME (t);
+      if (t && TREE_CODE (t) == TYPE_DECL)
 	{
 	  if (DECL_NAME (t))
 	    n = lang_hooks.decl_printable_name (t, 2);
 	}
-      else
-	{
-	  t = TYPE_NAME (t);
-	  if (t)
-	    n = IDENTIFIER_POINTER (t);
-	}
+      else if (t)
+	n = IDENTIFIER_POINTER (t);
       break;
 
     case 'E':
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 1ae82e82cab..6e2463b727e 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -46,6 +46,7 @@ Boston, MA 02111-1307, USA.  */
 #include "target-def.h"
 #include "langhooks.h"
 #include "cgraph.h"
+#include "tree-gimple.h"
 
 #ifndef CHECK_STACK_LIMIT
 #define CHECK_STACK_LIMIT (-1)
@@ -877,6 +878,7 @@ static bool ix86_expand_carry_flag_compare (enum rtx_code, rtx, rtx, rtx*);
 static tree ix86_build_builtin_va_list (void);
 static void ix86_setup_incoming_varargs (CUMULATIVE_ARGS *, enum machine_mode,
 					 tree, int *, int);
+static void ix86_gimplify_va_arg (tree *expr_p, tree *pre_p, tree *post_p);
 
 struct ix86_address
 {
@@ -1069,6 +1071,9 @@ static void init_ext_80387_constants (void);
 #undef TARGET_SETUP_INCOMING_VARARGS
 #define TARGET_SETUP_INCOMING_VARARGS ix86_setup_incoming_varargs
 
+#undef TARGET_GIMPLIFY_VA_ARG_EXPR
+#define TARGET_GIMPLIFY_VA_ARG_EXPR ix86_gimplify_va_arg
+
 struct gcc_target targetm = TARGET_INITIALIZER;
 
 
@@ -3410,6 +3415,258 @@ ix86_va_arg (tree valist, tree type)
 
   return addr_rtx;
 }
+
+/* Lower VA_ARG_EXPR at gimplification time.  */
+
+void
+ix86_gimplify_va_arg (tree *expr_p, tree *pre_p, tree *post_p)
+{
+  tree valist = TREE_OPERAND (*expr_p, 0);
+  tree type = TREE_TYPE (*expr_p);
+  static const int intreg[6] = { 0, 1, 2, 3, 4, 5 };
+  tree f_gpr, f_fpr, f_ovf, f_sav;
+  tree gpr, fpr, ovf, sav, t;
+  int size, rsize;
+  tree lab_false, lab_over = NULL_TREE;
+  tree addr, t2;
+  rtx container;
+  int indirect_p = 0;
+  tree ptrtype;
+
+  /* Only 64bit target needs something special.  */
+  if (!TARGET_64BIT)
+    {
+      std_gimplify_va_arg_expr (expr_p, pre_p, post_p);
+      return;
+    }
+
+  f_gpr = TYPE_FIELDS (TREE_TYPE (va_list_type_node));
+  f_fpr = TREE_CHAIN (f_gpr);
+  f_ovf = TREE_CHAIN (f_fpr);
+  f_sav = TREE_CHAIN (f_ovf);
+
+  valist = build_fold_indirect_ref (valist);
+  gpr = build (COMPONENT_REF, TREE_TYPE (f_gpr), valist, f_gpr);
+  fpr = build (COMPONENT_REF, TREE_TYPE (f_fpr), valist, f_fpr);
+  ovf = build (COMPONENT_REF, TREE_TYPE (f_ovf), valist, f_ovf);
+  sav = build (COMPONENT_REF, TREE_TYPE (f_sav), valist, f_sav);
+
+  size = int_size_in_bytes (type);
+  if (size == -1)
+    {
+      /* Variable-size types are passed by reference.  */
+      indirect_p = 1;
+      type = build_pointer_type (type);
+      size = int_size_in_bytes (type);
+    }
+  rsize = (size + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
+
+  container = construct_container (TYPE_MODE (type), type, 0,
+				   REGPARM_MAX, SSE_REGPARM_MAX, intreg, 0);
+  /*
+   * Pull the value out of the saved registers ...
+   */
+
+  addr = create_tmp_var (ptr_type_node, "addr");
+  DECL_POINTER_ALIAS_SET (addr) = get_varargs_alias_set ();
+
+  if (container)
+    {
+      int needed_intregs, needed_sseregs;
+      int need_temp;
+      tree int_addr, sse_addr;
+
+      lab_false = create_artificial_label ();
+      lab_over = create_artificial_label ();
+
+      examine_argument (TYPE_MODE (type), type, 0,
+		        &needed_intregs, &needed_sseregs);
+
+
+      need_temp = ((needed_intregs && TYPE_ALIGN (type) > 64)
+		   || TYPE_ALIGN (type) > 128);
+
+      /* In case we are passing structure, verify that it is consecutive block
+         on the register save area.  If not we need to do moves.  */
+      if (!need_temp && !REG_P (container))
+	{
+	  /* Verify that all registers are strictly consecutive  */
+	  if (SSE_REGNO_P (REGNO (XEXP (XVECEXP (container, 0, 0), 0))))
+	    {
+	      int i;
+
+	      for (i = 0; i < XVECLEN (container, 0) && !need_temp; i++)
+		{
+		  rtx slot = XVECEXP (container, 0, i);
+		  if (REGNO (XEXP (slot, 0)) != FIRST_SSE_REG + (unsigned int) i
+		      || INTVAL (XEXP (slot, 1)) != i * 16)
+		    need_temp = 1;
+		}
+	    }
+	  else
+	    {
+	      int i;
+
+	      for (i = 0; i < XVECLEN (container, 0) && !need_temp; i++)
+		{
+		  rtx slot = XVECEXP (container, 0, i);
+		  if (REGNO (XEXP (slot, 0)) != (unsigned int) i
+		      || INTVAL (XEXP (slot, 1)) != i * 8)
+		    need_temp = 1;
+		}
+	    }
+	}
+      if (!need_temp)
+	{
+	  int_addr = addr;
+	  sse_addr = addr;
+	}
+      else
+	{
+	  int_addr = create_tmp_var (ptr_type_node, "int_addr");
+	  DECL_POINTER_ALIAS_SET (int_addr) = get_varargs_alias_set ();
+	  sse_addr = create_tmp_var (ptr_type_node, "sse_addr");
+	  DECL_POINTER_ALIAS_SET (sse_addr) = get_varargs_alias_set ();
+	}
+      /* First ensure that we fit completely in registers.  */
+      if (needed_intregs)
+	{
+	  t = build_int_2 ((REGPARM_MAX - needed_intregs + 1) * 8, 0);
+	  TREE_TYPE (t) = TREE_TYPE (gpr);
+	  t = build2 (GE_EXPR, boolean_type_node, gpr, t);
+	  t2 = build1 (GOTO_EXPR, void_type_node, lab_false);
+	  t = build (COND_EXPR, void_type_node, t, t2, NULL_TREE);
+	  gimplify_and_add (t, pre_p);
+	}
+      if (needed_sseregs)
+	{
+	  t = build_int_2 ((SSE_REGPARM_MAX - needed_sseregs + 1) * 16
+			   + REGPARM_MAX * 8, 0);
+	  TREE_TYPE (t) = TREE_TYPE (fpr);
+	  t = build2 (GE_EXPR, boolean_type_node, fpr, t);
+	  t2 = build1 (GOTO_EXPR, void_type_node, lab_false);
+	  t = build (COND_EXPR, void_type_node, t, t2, NULL_TREE);
+	  gimplify_and_add (t, pre_p);
+	}
+
+      /* Compute index to start of area used for integer regs.  */
+      if (needed_intregs)
+	{
+	  /* int_addr = gpr + sav; */
+	  t = build2 (PLUS_EXPR, ptr_type_node, sav, gpr);
+	  t = build2 (MODIFY_EXPR, void_type_node, int_addr, t);
+	  gimplify_and_add (t, pre_p);
+	}
+      if (needed_sseregs)
+	{
+	  /* sse_addr = fpr + sav; */
+	  t = build2 (PLUS_EXPR, ptr_type_node, sav, fpr);
+	  t = build2 (MODIFY_EXPR, void_type_node, sse_addr, t);
+	  gimplify_and_add (t, pre_p);
+	}
+      if (need_temp)
+	{
+	  int i;
+	  tree temp = create_tmp_var (type, "va_arg_tmp");
+
+	  /* addr = &temp; */
+	  t = build1 (ADDR_EXPR, build_pointer_type (type), temp);
+	  t = build2 (MODIFY_EXPR, void_type_node, addr, t);
+	  gimplify_and_add (t, pre_p);
+	  
+	  for (i = 0; i < XVECLEN (container, 0); i++)
+	    {
+	      rtx slot = XVECEXP (container, 0, i);
+	      rtx reg = XEXP (slot, 0);
+	      enum machine_mode mode = GET_MODE (reg);
+	      tree piece_type = lang_hooks.types.type_for_mode (mode, 1);
+	      tree addr_type = build_pointer_type (piece_type);
+	      tree src_addr, src;
+	      int src_offset;
+	      tree dest_addr, dest;
+
+	      if (SSE_REGNO_P (REGNO (reg)))
+		{
+		  src_addr = sse_addr;
+		  src_offset = (REGNO (reg) - FIRST_SSE_REG) * 16;
+		}
+	      else
+		{
+		  src_addr = int_addr;
+		  src_offset = REGNO (reg) * 8;
+		}
+	      src_addr = convert (addr_type, src_addr);
+	      src_addr = fold (build2 (PLUS_EXPR, addr_type, src_addr,
+				       size_int (src_offset)));
+	      src = build_fold_indirect_ref (src_addr);
+
+	      dest_addr = convert (addr_type, addr);
+	      dest_addr = fold (build2 (PLUS_EXPR, addr_type, dest_addr,
+					size_int (INTVAL (XEXP (slot, 1)))));
+	      dest = build_fold_indirect_ref (dest_addr);
+
+	      t = build2 (MODIFY_EXPR, void_type_node, dest, src);
+	      gimplify_and_add (t, pre_p);
+	    }
+	}
+
+      if (needed_intregs)
+	{
+	  t = build2 (PLUS_EXPR, TREE_TYPE (gpr), gpr,
+		      build_int_2 (needed_intregs * 8, 0));
+	  t = build2 (MODIFY_EXPR, TREE_TYPE (gpr), gpr, t);
+	  gimplify_and_add (t, pre_p);
+	}
+      if (needed_sseregs)
+	{
+	  t =
+	    build2 (PLUS_EXPR, TREE_TYPE (fpr), fpr,
+		   build_int_2 (needed_sseregs * 16, 0));
+	  t = build2 (MODIFY_EXPR, TREE_TYPE (fpr), fpr, t);
+	  gimplify_and_add (t, pre_p);
+	}
+
+      t = build1 (GOTO_EXPR, void_type_node, lab_over);
+      gimplify_and_add (t, pre_p);
+
+      t = build1 (LABEL_EXPR, void_type_node, lab_false);
+      append_to_statement_list (t, pre_p);
+    }
+
+  /* ... otherwise out of the overflow area.  */
+
+  /* Care for on-stack alignment if needed.  */
+  if (FUNCTION_ARG_BOUNDARY (VOIDmode, type) <= 64)
+    t = ovf;
+  else
+    {
+      HOST_WIDE_INT align = FUNCTION_ARG_BOUNDARY (VOIDmode, type) / 8;
+      t = build (PLUS_EXPR, TREE_TYPE (ovf), ovf, build_int_2 (align - 1, 0));
+      t = build (BIT_AND_EXPR, TREE_TYPE (t), t, build_int_2 (-align, -1));
+    }
+  gimplify_expr (&t, pre_p, NULL, is_gimple_val, fb_rvalue);
+
+  t2 = build2 (MODIFY_EXPR, void_type_node, addr, t);
+  gimplify_and_add (t2, pre_p);
+
+  t = build2 (PLUS_EXPR, TREE_TYPE (t), t,
+	      build_int_2 (rsize * UNITS_PER_WORD, 0));
+  t = build2 (MODIFY_EXPR, TREE_TYPE (ovf), ovf, t);
+  gimplify_and_add (t, pre_p);
+
+  if (container)
+    {
+      t = build1 (LABEL_EXPR, void_type_node, lab_over);
+      append_to_statement_list (t, pre_p);
+    }
+
+  ptrtype = build_pointer_type (type);
+  addr = convert (ptrtype, addr);
+
+  if (indirect_p)
+    addr = build_fold_indirect_ref (addr);
+  *expr_p = build_fold_indirect_ref (addr);
+}
 
 /* Return nonzero if OP is either a i387 or SSE fp register.  */
 int
diff --git a/gcc/config/ia64/ia64.c b/gcc/config/ia64/ia64.c
index 0891ed23cd8..14fdfe25a1c 100644
--- a/gcc/config/ia64/ia64.c
+++ b/gcc/config/ia64/ia64.c
@@ -51,6 +51,7 @@ Boston, MA 02111-1307, USA.  */
 #include "hashtab.h"
 #include "langhooks.h"
 #include "cfglayout.h"
+#include "tree-gimple.h"
 
 /* This is used for communication between ASM_OUTPUT_LABEL and
    ASM_OUTPUT_LABELREF.  */
@@ -273,6 +274,7 @@ static void ia64_vms_init_libfuncs (void)
 static tree ia64_handle_model_attribute (tree *, tree, tree, int, bool *);
 static void ia64_encode_section_info (tree, rtx, int);
 static rtx ia64_struct_value_rtx (tree, int);
+static void ia64_gimplify_va_arg (tree *, tree *, tree *);
 
 
 /* Table of valid machine attributes.  */
@@ -407,6 +409,9 @@ static const struct attribute_spec ia64_attribute_table[] =
 #undef TARGET_STRICT_ARGUMENT_NAMING
 #define TARGET_STRICT_ARGUMENT_NAMING hook_bool_CUMULATIVE_ARGS_true
 
+#undef TARGET_GIMPLIFY_VA_ARG_EXPR
+#define TARGET_GIMPLIFY_VA_ARG_EXPR ia64_gimplify_va_arg
+
 struct gcc_target targetm = TARGET_INITIALIZER;
 
 /* Return 1 if OP is a valid operand for the MEM of a CALL insn.  */
@@ -3987,6 +3992,39 @@ ia64_va_arg (tree valist, tree type)
 
   return std_expand_builtin_va_arg (valist, type);
 }
+
+static void
+ia64_gimplify_va_arg (tree *expr_p, tree *pre_p, tree *post_p)
+{
+  tree valist = TREE_OPERAND (*expr_p, 0);
+  tree type = TREE_TYPE (*expr_p);
+
+  /* Variable sized types are passed by reference.  */
+  if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
+    {
+      TREE_TYPE (*expr_p) = build_pointer_type (type);
+      std_gimplify_va_arg_expr (expr_p, pre_p, post_p);
+      *expr_p = build_fold_indirect_ref (*expr_p);
+      return;
+    }
+
+  /* Aggregate arguments with alignment larger than 8 bytes start at
+     the next even boundary.  Integer and floating point arguments
+     do so if they are larger than 8 bytes, whether or not they are
+     also aligned larger than 8 bytes.  */
+  if ((TREE_CODE (type) == REAL_TYPE || TREE_CODE (type) == INTEGER_TYPE)
+      ? int_size_in_bytes (type) > 8 : TYPE_ALIGN (type) > 8 * BITS_PER_UNIT)
+    {
+      tree t = build (PLUS_EXPR, TREE_TYPE (valist), valist,
+		      build_int_2 (2 * UNITS_PER_WORD - 1, 0));
+      t = build (BIT_AND_EXPR, TREE_TYPE (t), t,
+		 build_int_2 (-2 * UNITS_PER_WORD, -1));
+      t = build (MODIFY_EXPR, TREE_TYPE (valist), valist, t);
+      gimplify_and_add (t, pre_p);
+    }
+
+  std_gimplify_va_arg_expr (expr_p, pre_p, post_p);
+}
 
 /* Return 1 if function return value returned in memory.  Return 0 if it is
    in a register.  */
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 79bc885d958..d0bc91d40d6 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -52,6 +52,7 @@
 #include "reload.h"
 #include "cfglayout.h"
 #include "sched-int.h"
+#include "tree-gimple.h"
 #if TARGET_XCOFF
 #include "xcoffout.h"  /* get declarations of xcoff_*_section_name */
 #endif
@@ -439,6 +440,7 @@ static tree get_prev_label (tree function_name);
 #endif
 
 static tree rs6000_build_builtin_va_list (void);
+static void rs6000_gimplify_va_arg (tree *, tree *, tree *);
 
 /* Hash table stuff for keeping track of TOC entries.  */
 
@@ -647,6 +649,9 @@ static const char alt_reg_names[][8] =
 #undef TARGET_BUILD_BUILTIN_VA_LIST
 #define TARGET_BUILD_BUILTIN_VA_LIST rs6000_build_builtin_va_list
 
+#undef TARGET_GIMPLIFY_VA_ARG_EXPR
+#define TARGET_GIMPLIFY_VA_ARG_EXPR rs6000_gimplify_va_arg
+
 struct gcc_target targetm = TARGET_INITIALIZER;
 
 
@@ -5287,6 +5292,243 @@ rs6000_va_arg (tree valist, tree type)
   return addr_rtx;
 }
 
+void
+rs6000_gimplify_va_arg (tree *expr_p, tree *pre_p, tree *post_p)
+{
+  tree valist = TREE_OPERAND (*expr_p, 0);
+  tree type = TREE_TYPE (*expr_p);
+  tree f_gpr, f_fpr, f_res, f_ovf, f_sav;
+  tree gpr, fpr, ovf, sav, reg, t, u;
+  int indirect_p, size, rsize, n_reg, sav_ofs, sav_scale;
+  tree lab_false, lab_over, addr;
+  int align;
+  tree ptrtype = build_pointer_type (type);
+
+  if (DEFAULT_ABI != ABI_V4)
+    {
+      /* Variable sized types are passed by reference, as are AltiVec
+	 vectors when 32-bit and not using the AltiVec ABI extension.  */
+      if (int_size_in_bytes (type) < 0
+	  || (TARGET_32BIT
+	      && !TARGET_ALTIVEC_ABI
+	      && ALTIVEC_VECTOR_MODE (TYPE_MODE (type))))
+	{
+	  /* Args grow upward.  */
+	  t = build2 (POSTINCREMENT_EXPR, TREE_TYPE (valist), valist,
+		      build_int_2 (POINTER_SIZE / BITS_PER_UNIT, 0));
+	  t = build1 (NOP_EXPR, build_pointer_type (ptrtype), t);
+	  t = build_fold_indirect_ref (t);
+	  t = build_fold_indirect_ref (t);
+
+	  *expr_p = t;
+	  return;
+	}
+      if (targetm.calls.split_complex_arg
+	  && TREE_CODE (type) == COMPLEX_TYPE)
+	{
+	  tree elem_type = TREE_TYPE (type);
+	  enum machine_mode elem_mode = TYPE_MODE (elem_type);
+	  int elem_size = GET_MODE_SIZE (elem_mode);
+
+	  if (elem_size < UNITS_PER_WORD)
+	    {
+	      tree real_part, imag_addr, dest_real, rr;
+	      tree post = NULL_TREE;
+
+	      /* This is a bit tricky because we can't just feed the
+		 VA_ARG_EXPRs back into gimplify_expr; if we did,
+		 gimplify_va_arg_expr would complain about trying to pass a
+		 float. */
+	      real_part = build1 (VA_ARG_EXPR, elem_type, valist);
+	      rs6000_gimplify_va_arg (&real_part, pre_p, &post);
+	      gimplify_expr (&real_part, pre_p, &post, is_gimple_val,
+			     fb_rvalue);
+	      append_to_statement_list (post, pre_p);
+
+	      imag_addr = build1 (VA_ARG_EXPR, elem_type, valist);
+	      rs6000_gimplify_va_arg (&imag_addr, pre_p, post_p);
+	      imag_addr = build_fold_addr_expr (imag_addr);
+	      gimplify_expr (&imag_addr, pre_p, post_p, is_gimple_val,
+			     fb_rvalue);
+
+	      /* We're not returning the value here, but the address.
+		 real_part and imag_part are not contiguous, and we know
+		 there is space available to pack real_part next to
+		 imag_part.  float _Complex is not promoted to
+		 double _Complex by the default promotion rules that
+		 promote float to double.  */
+	      if (2 * elem_size > UNITS_PER_WORD)
+		abort ();
+
+	      dest_real = fold (build2 (MINUS_EXPR, TREE_TYPE (imag_addr),
+					imag_addr, ssize_int (elem_size)));
+	      gimplify_expr (&dest_real, pre_p, post_p, is_gimple_val,
+			     fb_rvalue);
+
+	      rr = build_fold_indirect_ref (dest_real);
+	      rr = build2 (MODIFY_EXPR, void_type_node, rr, real_part);
+	      gimplify_and_add (rr, pre_p);
+
+	      dest_real = convert (build_pointer_type (type), dest_real);
+	      *expr_p = build_fold_indirect_ref (dest_real);
+
+	      return;
+	    }
+	}
+
+      std_gimplify_va_arg_expr (expr_p, pre_p, post_p);
+      return;
+    }
+
+  f_gpr = TYPE_FIELDS (TREE_TYPE (va_list_type_node));
+  f_fpr = TREE_CHAIN (f_gpr);
+  f_res = TREE_CHAIN (f_fpr);
+  f_ovf = TREE_CHAIN (f_res);
+  f_sav = TREE_CHAIN (f_ovf);
+
+  valist = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (valist)), valist);
+  gpr = build (COMPONENT_REF, TREE_TYPE (f_gpr), valist, f_gpr);
+  fpr = build (COMPONENT_REF, TREE_TYPE (f_fpr), valist, f_fpr);
+  ovf = build (COMPONENT_REF, TREE_TYPE (f_ovf), valist, f_ovf);
+  sav = build (COMPONENT_REF, TREE_TYPE (f_sav), valist, f_sav);
+
+  size = int_size_in_bytes (type);
+  rsize = (size + 3) / 4;
+  align = 1;
+
+  if (AGGREGATE_TYPE_P (type)
+      || TYPE_MODE (type) == TFmode
+      || (!TARGET_ALTIVEC_ABI && ALTIVEC_VECTOR_MODE (TYPE_MODE (type))))
+    {
+      /* Aggregates, long doubles, and AltiVec vectors are passed by
+	 reference.  */
+      indirect_p = 1;
+      reg = gpr;
+      n_reg = 1;
+      sav_ofs = 0;
+      sav_scale = 4;
+      size = 4;
+      rsize = 1;
+    }
+  else if (TARGET_HARD_FLOAT && TARGET_FPRS
+	   && (TYPE_MODE (type) == SFmode || TYPE_MODE (type) == DFmode))
+    {
+      /* FP args go in FP registers, if present.  */
+      indirect_p = 0;
+      reg = fpr;
+      n_reg = 1;
+      sav_ofs = 8*4;
+      sav_scale = 8;
+      if (TYPE_MODE (type) == DFmode)
+	align = 8;
+    }
+  else
+    {
+      /* Otherwise into GP registers.  */
+      indirect_p = 0;
+      reg = gpr;
+      n_reg = rsize;
+      sav_ofs = 0;
+      sav_scale = 4;
+      if (n_reg == 2)
+	align = 8;
+    }
+
+  /* Pull the value out of the saved registers....  */
+
+  lab_over = NULL;
+  addr = create_tmp_var (ptr_type_node, "addr");
+  DECL_POINTER_ALIAS_SET (addr) = get_varargs_alias_set ();
+
+  /*  AltiVec vectors never go in registers when -mabi=altivec.  */
+  if (TARGET_ALTIVEC_ABI && ALTIVEC_VECTOR_MODE (TYPE_MODE (type)))
+    align = 16;
+  else
+    {
+      lab_false = create_artificial_label ();
+      lab_over = create_artificial_label ();
+
+      /* Long long and SPE vectors are aligned in the registers.
+	 As are any other 2 gpr item such as complex int due to a
+	 historical mistake.  */
+      u = reg;
+      if (n_reg == 2)
+	{
+	  u = build2 (BIT_AND_EXPR, TREE_TYPE (reg), reg,
+		     build_int_2 (n_reg - 1, 0));
+	  u = build2 (POSTINCREMENT_EXPR, TREE_TYPE (reg), reg, u);
+	}
+
+      t = build_int_2 (8 - n_reg + 1, 0);
+      TREE_TYPE (t) = TREE_TYPE (reg);
+      t = build2 (GE_EXPR, boolean_type_node, u, t);
+      u = build1 (GOTO_EXPR, void_type_node, lab_false);
+      t = build3 (COND_EXPR, void_type_node, t, u, NULL_TREE);
+      gimplify_and_add (t, pre_p);
+
+      t = sav;
+      if (sav_ofs)
+	t = build2 (PLUS_EXPR, ptr_type_node, sav, build_int_2 (sav_ofs, 0));
+
+      u = build2 (POSTINCREMENT_EXPR, TREE_TYPE (reg), reg,
+		 build_int_2 (n_reg, 0));
+      u = build1 (CONVERT_EXPR, integer_type_node, u);
+      u = build2 (MULT_EXPR, integer_type_node, u, build_int_2 (sav_scale, 0));
+      t = build2 (PLUS_EXPR, ptr_type_node, t, u);
+
+      t = build2 (MODIFY_EXPR, void_type_node, addr, t);
+      gimplify_and_add (t, pre_p);
+
+      t = build1 (GOTO_EXPR, void_type_node, lab_over);
+      gimplify_and_add (t, pre_p);
+
+      t = build1 (LABEL_EXPR, void_type_node, lab_false);
+      append_to_statement_list (t, pre_p);
+
+      if (n_reg > 2)
+	{
+	  /* Ensure that we don't find any more args in regs.
+	     Alignment has taken care of the n_reg == 2 case.  */
+	  t = build (MODIFY_EXPR, TREE_TYPE (reg), reg, build_int_2 (8, 0));
+	  gimplify_and_add (t, pre_p);
+	}
+    }
+
+  /* ... otherwise out of the overflow area.  */
+
+  /* Care for on-stack alignment if needed.  */
+  t = ovf;
+  if (align != 1)
+    {
+      t = build2 (PLUS_EXPR, TREE_TYPE (t), t, build_int_2 (align - 1, 0));
+      t = build2 (BIT_AND_EXPR, TREE_TYPE (t), t, build_int_2 (-align, -1));
+    }
+  gimplify_expr (&t, pre_p, NULL, is_gimple_val, fb_rvalue);
+
+  u = build2 (MODIFY_EXPR, void_type_node, addr, t);
+  gimplify_and_add (u, pre_p);
+
+  t = build2 (PLUS_EXPR, TREE_TYPE (t), t, build_int_2 (size, 0));
+  t = build2 (MODIFY_EXPR, TREE_TYPE (ovf), ovf, t);
+  gimplify_and_add (t, pre_p);
+
+  if (lab_over)
+    {
+      t = build1 (LABEL_EXPR, void_type_node, lab_over);
+      append_to_statement_list (t, pre_p);
+    }
+
+  if (indirect_p)
+    {
+      addr = convert (build_pointer_type (ptrtype), addr);
+      addr = build_fold_indirect_ref (addr);
+    }
+  else
+    addr = convert (ptrtype, addr);
+
+  *expr_p = build_fold_indirect_ref (addr);
+}
+
 /* Builtins.  */
 
 #define def_builtin(MASK, NAME, TYPE, CODE)			\
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index b63f1c23671..ecd59f844f7 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -10001,4 +10001,73 @@ fold_relational_const (enum tree_code code, tree type, tree op0, tree op1)
   return tem;
 }
 
+/* Build an expression for the address of T.  Folds away INDIRECT_REF to
+   avoid confusing the gimplify process.  */
+
+tree
+build_fold_addr_expr_with_type (tree t, tree ptrtype)
+{
+  if (TREE_CODE (t) == INDIRECT_REF)
+    {
+      t = TREE_OPERAND (t, 0);
+      if (TREE_TYPE (t) != ptrtype)
+	t = build1 (NOP_EXPR, ptrtype, t);
+    }
+  else
+    {
+      tree base = t;
+      while (TREE_CODE (base) == COMPONENT_REF
+	     || TREE_CODE (base) == ARRAY_REF)
+	base = TREE_OPERAND (base, 0);
+      if (DECL_P (base))
+	TREE_ADDRESSABLE (base) = 1;
+
+      t = build1 (ADDR_EXPR, ptrtype, t);
+    }
+
+  return t;
+}
+
+tree
+build_fold_addr_expr (tree t)
+{
+  return build_fold_addr_expr_with_type (t, build_pointer_type (TREE_TYPE (t)));
+}
+
+/* Builds an expression for an indirection through T, simplifying some
+   cases.  */
+
+tree
+build_fold_indirect_ref (tree t)
+{
+  tree type = TREE_TYPE (TREE_TYPE (t));
+  tree sub = t;
+  tree subtype;
+
+  STRIP_NOPS (sub);
+  if (TREE_CODE (sub) == ADDR_EXPR)
+    {
+      tree op = TREE_OPERAND (sub, 0);
+      tree optype = TREE_TYPE (op);
+      /* *&p => p */
+      if (lang_hooks.types_compatible_p (type, optype))
+	return op;
+      /* *(foo *)&fooarray => fooarray[0] */
+      else if (TREE_CODE (optype) == ARRAY_TYPE
+	       && lang_hooks.types_compatible_p (type, TREE_TYPE (optype)))
+	return build2 (ARRAY_REF, type, op, size_zero_node);
+    }
+
+  /* *(foo *)fooarrptr => (*fooarrptr)[0] */
+  subtype = TREE_TYPE (sub);
+  if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
+      && lang_hooks.types_compatible_p (type, TREE_TYPE (TREE_TYPE (subtype))))
+    {
+      sub = build_fold_indirect_ref (sub);
+      return build2 (ARRAY_REF, type, sub, size_zero_node);
+    }
+
+  return build1 (INDIRECT_REF, type, t);
+}
+
 #include "gt-fold-const.h"
diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index c6378aa4d29..c25a89171b3 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -45,6 +45,7 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 #include "output.h"
 #include "expr.h"
 #include "ggc.h"
+#include "target.h"
 
 static struct gimplify_ctx
 {
@@ -237,6 +238,15 @@ append_to_statement_list_force (tree t, tree *list_p)
   append_to_statement_list_1 (t, list_p, t != NULL);
 }
 
+/* Both gimplify the statement T and append it to LIST_P.  */
+
+void
+gimplify_and_add (tree t, tree *list_p)
+{
+  gimplify_stmt (&t);
+  append_to_statement_list (t, list_p);
+}
+
 /* Add T to the end of a COMPOUND_EXPR pointed by LIST_P.  The type
    of the result is the type of T.  */
 
@@ -668,13 +678,17 @@ copy_if_shared_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
   else
     {
       TREE_VISITED (t) = 1;
-      if (TREE_CODE (*tp) == VA_ARG_EXPR)
+      if (TREE_CODE (*tp) == VA_ARG_EXPR
+	  && targetm.calls.gimplify_va_arg_expr == NULL)
 	{
 	  /* Mark any _DECL inside the operand as volatile to avoid
 	     the optimizers messing around with it. We have to do this
 	     early, otherwise we might mark a variable as volatile
 	     after we gimplify other statements that use the variable
 	     assuming it's not volatile.  */
+
+	  /* FIXME once most targets define the above hook, this should
+	     go away (perhaps along with the #include "target.h").  */
 	  walk_tree (&TREE_OPERAND (*tp, 0), mark_decls_volatile_r,
 		     NULL, NULL);
 	}
@@ -1633,39 +1647,6 @@ gimplify_minimax_expr (tree *expr_p, tree *pre_p, tree *post_p)
     return GS_OK;
 }
 
-/*  Build an expression for the address of T.  Folds away INDIRECT_REF to
-    avoid confusing the gimplify process.  */
-
-static tree
-build_addr_expr_with_type (tree t, tree ptrtype)
-{
-  if (TREE_CODE (t) == INDIRECT_REF)
-    {
-      t = TREE_OPERAND (t, 0);
-      if (TREE_TYPE (t) != ptrtype)
-	t = build1 (NOP_EXPR, ptrtype, t);
-    }
-  else
-    {
-      tree base = t;
-      while (TREE_CODE (base) == COMPONENT_REF
-	     || TREE_CODE (base) == ARRAY_REF)
-	base = TREE_OPERAND (base, 0);
-      if (DECL_P (base))
-	TREE_ADDRESSABLE (base) = 1;
-
-      t = build1 (ADDR_EXPR, ptrtype, t);
-    }
-
-  return t;
-}
-
-static tree
-build_addr_expr (tree t)
-{
-  return build_addr_expr_with_type (t, build_pointer_type (TREE_TYPE (t)));
-}
-
 /* Subroutine of gimplify_compound_lval and gimplify_array_ref.
    Converts an ARRAY_REF to the equivalent *(&array + offset) form.  */
 
@@ -1716,7 +1697,7 @@ gimplify_array_ref_to_plus (tree *expr_p, tree *pre_p, tree *post_p)
   if (ret == GS_ERROR)
     return ret;
 
-  addr = build_addr_expr_with_type (array, ptrtype);
+  addr = build_fold_addr_expr_with_type (array, ptrtype);
   result = fold (build (add_code, ptrtype, addr, offset));
   *expr_p = build1 (INDIRECT_REF, elttype, result);
 
@@ -2533,9 +2514,9 @@ gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value)
 	  t = TYPE_SIZE_UNIT (TREE_TYPE (*to_p));
 	  t = unshare_expr (t);
 	  args = tree_cons (NULL, t, NULL);
-	  t = build_addr_expr (*from_p);
+	  t = build_fold_addr_expr (*from_p);
 	  args = tree_cons (NULL, t, args);
-	  dest = build_addr_expr (*to_p);
+	  dest = build_fold_addr_expr (*to_p);
 	  args = tree_cons (NULL, dest, args);
 	  t = implicit_built_in_decls[BUILT_IN_MEMCPY];
 	  t = build_function_call_expr (t, args);
@@ -3239,14 +3220,7 @@ gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p,
 	  break;
 
 	case VA_ARG_EXPR:
-	  /* Mark any _DECL inside the operand as volatile to avoid the
-	     optimizers messing around with it. FIXME: Remove this once
-	     VA_ARG_EXPRs are properly lowered.  */
-	  walk_tree (&TREE_OPERAND (*expr_p, 0), mark_decls_volatile_r,
-		     NULL, NULL);
-
-	  /* va_arg expressions are in GIMPLE form already.  */
-	  ret = GS_ALL_DONE;
+	  ret = gimplify_va_arg_expr (expr_p, pre_p, post_p);
 	  break;
 
 	case CONVERT_EXPR:
@@ -3586,7 +3560,7 @@ gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p,
       /* An lvalue will do.  Take the address of the expression, store it
 	 in a temporary, and replace the expression with an INDIRECT_REF of
 	 that temporary.  */
-      tmp = build_addr_expr (*expr_p);
+      tmp = build_fold_addr_expr (*expr_p);
       gimplify_expr (&tmp, pre_p, post_p, is_gimple_reg, fb_rvalue);
       *expr_p = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (tmp)), tmp);
     }
diff --git a/gcc/target-def.h b/gcc/target-def.h
index f8c832a251e..40e9610ef61 100644
--- a/gcc/target-def.h
+++ b/gcc/target-def.h
@@ -358,6 +358,14 @@ Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
   default_pretend_outgoing_varargs_named
 #define TARGET_SPLIT_COMPLEX_ARG NULL
 
+#ifdef EXPAND_BUILTIN_VA_ARG
+/* If there's a target-specific va_arg expander, there needs to be a
+   target-specific gimplifier.  */
+#define TARGET_GIMPLIFY_VA_ARG_EXPR NULL
+#else
+#define TARGET_GIMPLIFY_VA_ARG_EXPR std_gimplify_va_arg_expr
+#endif
+
 #define TARGET_CALLS {						\
    TARGET_PROMOTE_FUNCTION_ARGS,				\
    TARGET_PROMOTE_FUNCTION_RETURN,				\
@@ -370,6 +378,7 @@ Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
    TARGET_STRICT_ARGUMENT_NAMING,				\
    TARGET_PRETEND_OUTGOING_VARARGS_NAMED,			\
    TARGET_SPLIT_COMPLEX_ARG,					\
+   TARGET_GIMPLIFY_VA_ARG_EXPR,					\
    }
 
 /* The whole shebang.  */
diff --git a/gcc/target.h b/gcc/target.h
index a7eb743b7d1..a2a564619fa 100644
--- a/gcc/target.h
+++ b/gcc/target.h
@@ -470,6 +470,10 @@ struct gcc_target
     /* Given a complex type T, return true if a parameter of type T
        should be passed as two scalars.  */
     bool (* split_complex_arg) (tree type);
+
+    /* Gimplifies a VA_ARG_EXPR.  */
+    void (* gimplify_va_arg_expr) (tree *expr_p, tree *pre_p,
+				   tree *post_p);
   } calls;
 
   /* Leave the boolean fields at the end.  */
diff --git a/gcc/tree-gimple.h b/gcc/tree-gimple.h
index 59cb3b365ac..eb3dea86e85 100644
--- a/gcc/tree-gimple.h
+++ b/gcc/tree-gimple.h
@@ -107,6 +107,7 @@ void gimplify_to_stmt_list (tree *);
 void gimplify_body (tree *, tree);
 void push_gimplify_context (void);
 void pop_gimplify_context (tree);
+void gimplify_and_add (tree, tree *);
 
 /* Miscellaneous helpers.  */
 tree get_base_address (tree t);
@@ -121,6 +122,8 @@ tree build_and_jump (tree *);
 tree alloc_stmt_list (void);
 void free_stmt_list (tree);
 tree force_labels_r (tree *, int *, void *);
+enum gimplify_status gimplify_va_arg_expr (tree *, tree *, tree *);
+void std_gimplify_va_arg_expr (tree *, tree *, tree *);
 
 /* In tree-nested.c.  */
 extern void lower_nested_functions (tree);
diff --git a/gcc/tree.h b/gcc/tree.h
index c6a9f078eca..03c6415d275 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -1602,7 +1602,7 @@ struct tree_block GTY(())
 #define TYPE_VECTOR_SUBPARTS(VECTOR_TYPE) \
   GET_MODE_NUNITS (VECTOR_TYPE_CHECK (VECTOR_TYPE)->type.mode)
 
-  /* Indicates that objects of this type must be initialized by calling a
+/* Indicates that objects of this type must be initialized by calling a
    function when they are created.  */
 #define TYPE_NEEDS_CONSTRUCTING(NODE) \
   (TYPE_CHECK (NODE)->type.needs_constructing_flag)
@@ -3468,6 +3468,9 @@ extern tree nondestructive_fold_unary_to_constant (enum tree_code, tree, tree);
 extern tree nondestructive_fold_binary_to_constant (enum tree_code, tree, tree, tree);
 extern tree fold_read_from_constant_string (tree);
 extern tree int_const_binop (enum tree_code, tree, tree, int);
+extern tree build_fold_addr_expr (tree);
+extern tree build_fold_addr_expr_with_type (tree, tree);
+extern tree build_fold_indirect_ref (tree);
 
 /* In builtins.c */
 extern tree fold_builtin (tree);