From 98f96ba187da56d93a8b58e794bd6acb58c7034c Mon Sep 17 00:00:00 2001
From: Kevin Buettner <kevinb@redhat.com>
Date: Sat, 2 Jun 2001 01:37:20 +0000
Subject: [PATCH] Make alignment of struct arguments in inferior function calls
 comply with the IA-64 Software Conventions and Runtime manual.

---
 gdb/ChangeLog   |  9 +++++++++
 gdb/ia64-tdep.c | 50 +++++++++++++++++++++++++++++++++++++++++++------
 2 files changed, 53 insertions(+), 6 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index a737322f75f..507c5c0614f 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,12 @@
+2001-06-01  Kevin Buettner  <kevinb@redhat.com>
+
+	* ia64-tdep.c (is_float_or_hfa_type_recurse): Call check_typedef()
+	on types that we wish to recurse on.
+	(slot_alignment_is_next_even): New function.
+	(ia64_push_arguments): Call slot_alignment_is_next_even() to
+	examine the type in order to decide if it's necessary to skip
+	an odd slot.
+
 2001-06-01  Michael Snyder  <msnyder@redhat.com>
 
 	* thread.c (delete_step_resume_breakpoint): New function.
diff --git a/gdb/ia64-tdep.c b/gdb/ia64-tdep.c
index afa0e1c76b9..cc2d0f23adc 100644
--- a/gdb/ia64-tdep.c
+++ b/gdb/ia64-tdep.c
@@ -1534,14 +1534,17 @@ is_float_or_hfa_type_recurse (struct type *t, struct type **etp)
 	}
       break;
     case TYPE_CODE_ARRAY:
-      return is_float_or_hfa_type_recurse (TYPE_TARGET_TYPE (t), etp);
+      return
+	is_float_or_hfa_type_recurse (check_typedef (TYPE_TARGET_TYPE (t)),
+				      etp);
       break;
     case TYPE_CODE_STRUCT:
       {
 	int i;
 
 	for (i = 0; i < TYPE_NFIELDS (t); i++)
-	  if (!is_float_or_hfa_type_recurse (TYPE_FIELD_TYPE (t, i), etp))
+	  if (!is_float_or_hfa_type_recurse
+	      (check_typedef (TYPE_FIELD_TYPE (t, i)), etp))
 	    return 0;
 	return 1;
       }
@@ -1565,6 +1568,40 @@ is_float_or_hfa_type (struct type *t)
 }
 
 
+/* Return 1 if the alignment of T is such that the next even slot
+   should be used.  Return 0, if the next available slot should
+   be used.  (See section 8.5.1 of the IA-64 Software Conventions
+   and Runtime manual.)  */
+
+static int
+slot_alignment_is_next_even (struct type *t)
+{
+  switch (TYPE_CODE (t))
+    {
+    case TYPE_CODE_INT:
+    case TYPE_CODE_FLT:
+      if (TYPE_LENGTH (t) > 8)
+	return 1;
+      else
+	return 0;
+    case TYPE_CODE_ARRAY:
+      return
+	slot_alignment_is_next_even (check_typedef (TYPE_TARGET_TYPE (t)));
+    case TYPE_CODE_STRUCT:
+      {
+	int i;
+
+	for (i = 0; i < TYPE_NFIELDS (t); i++)
+	  if (slot_alignment_is_next_even
+	      (check_typedef (TYPE_FIELD_TYPE (t, i))))
+	    return 1;
+	return 0;
+      }
+    default:
+      return 0;
+    }
+}
+
 /* Attempt to find (and return) the global pointer for the given
    function.
 
@@ -1732,9 +1769,7 @@ ia64_push_arguments (int nargs, value_ptr *args, CORE_ADDR sp,
       type = check_typedef (VALUE_TYPE (arg));
       len = TYPE_LENGTH (type);
 
-      /* FIXME: This is crude and it is wrong (IMO), but it matches
-         what gcc does, I think. */
-      if (len > 8 && (nslots & 1))
+      if ((nslots & 1) && slot_alignment_is_next_even (type))
 	nslots++;
 
       if (TYPE_CODE (type) == TYPE_CODE_FUNC)
@@ -1809,8 +1844,11 @@ ia64_push_arguments (int nargs, value_ptr *args, CORE_ADDR sp,
 	}
 
       /* Normal slots */
-      if (len > 8 && (slotnum & 1))
+
+      /* Skip odd slot if necessary...  */
+      if ((slotnum & 1) && slot_alignment_is_next_even (type))
 	slotnum++;
+
       argoffset = 0;
       while (len > 0)
 	{
-- 
2.30.2