Merge in gcc2-ss-010999

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@29150 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 37 insertions, 1 deletions

diff --git a/gcc/rtl.c b/gcc/rtl.c
index db28096ac65..1c5bf6db4cb 100644
--- a/gcc/rtl.c
+++ b/gcc/rtl.c
@@ -1,5 +1,6 @@
 /* Allocate and read RTL for GNU C Compiler.
-   Copyright (C) 1987, 1988, 1991, 1994, 1997, 1998 Free Software Foundation, Inc.
+   Copyright (C) 1987, 1988, 1991, 1994, 1997, 1998, 1999
+   Free Software Foundation, Inc.
 
 This file is part of GNU CC.
 
@@ -309,6 +310,41 @@ rtx_alloc (code)
   return rt;
 }
 
+/* Like the above, but allocate based only on the length.  This is called
+   by the routines built into genrtl.c.  */
+
+rtx
+obstack_alloc_rtx (length)
+     int length;
+{
+  rtx rt;
+  register struct obstack *ob = rtl_obstack;
+
+  /* This function is called more than any other in GCC,
+     so we manipulate the obstack directly.
+
+     Even though rtx objects are word aligned, we may be sharing an obstack
+     with tree nodes, which may have to be double-word aligned.  So align
+     our length to the alignment mask in the obstack.  */
+
+  length = (length + ob->alignment_mask) & ~ ob->alignment_mask;
+
+  if (ob->chunk_limit - ob->next_free < length)
+    _obstack_newchunk (ob, length);
+
+  rt = (rtx) ob->object_base;
+  ob->next_free += length;
+  ob->object_base = ob->next_free;
+
+  /* We want to clear everything up to the FLD array.  Normally,
+     this is one int, but we don't want to assume that and it
+     isn't very portable anyway; this is.  */
+
+  memset (rt, 0, sizeof (struct rtx_def) - sizeof (rtunion));
+
+  return rt;
+}
+
 /* Free the rtx X and all RTL allocated since X.  */
 
 void