From 58fe50d5c90eb14e3cecacf66035751fcc06dd3b Mon Sep 17 00:00:00 2001
From: Bin Cheng <bin.cheng@arm.com>
Date: Mon, 28 Oct 2013 03:26:58 +0000
Subject: [PATCH] tree-ssa-loop-ivopts.c (strip_offset_1): Change parameter
 type.

	* tree-ssa-loop-ivopts.c (strip_offset_1): Change parameter type.
	Count DECL_FIELD_BIT_OFFSET for COMPONENT_REF.
	(strip_offset): Convert offset to unsigned number.

From-SVN: r204116
---
 gcc/ChangeLog              |  6 +++++
 gcc/tree-ssa-loop-ivopts.c | 46 +++++++++++++++++++++++++-------------
 2 files changed, 37 insertions(+), 15 deletions(-)

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8d6147a3188..461439a308b 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2013-10-28  Bin Cheng  <bin.cheng@arm.com>
+
+	* tree-ssa-loop-ivopts.c (strip_offset_1): Change parameter type.
+	Count DECL_FIELD_BIT_OFFSET for COMPONENT_REF.
+	(strip_offset): Convert offset to unsigned number.
+
 2013-10-27  Tom de Vries  <tom@codesourcery.com>
 
 	* cfgexpand.c (gimple_expand_cfg): Remove test for parm_birth_insn.
diff --git a/gcc/tree-ssa-loop-ivopts.c b/gcc/tree-ssa-loop-ivopts.c
index bd2e6297785..0210dbbad3d 100644
--- a/gcc/tree-ssa-loop-ivopts.c
+++ b/gcc/tree-ssa-loop-ivopts.c
@@ -2023,12 +2023,12 @@ find_interesting_uses (struct ivopts_data *data)
 
 static tree
 strip_offset_1 (tree expr, bool inside_addr, bool top_compref,
-		unsigned HOST_WIDE_INT *offset)
+		HOST_WIDE_INT *offset)
 {
   tree op0 = NULL_TREE, op1 = NULL_TREE, tmp, step;
   enum tree_code code;
   tree type, orig_type = TREE_TYPE (expr);
-  unsigned HOST_WIDE_INT off0, off1, st;
+  HOST_WIDE_INT off0, off1, st;
   tree orig_expr = expr;
 
   STRIP_NOPS (expr);
@@ -2119,19 +2119,32 @@ strip_offset_1 (tree expr, bool inside_addr, bool top_compref,
       break;
 
     case COMPONENT_REF:
-      if (!inside_addr)
-	return orig_expr;
+      {
+	tree field;
 
-      tmp = component_ref_field_offset (expr);
-      if (top_compref
-	  && cst_and_fits_in_hwi (tmp))
-	{
-	  /* Strip the component reference completely.  */
-	  op0 = TREE_OPERAND (expr, 0);
-	  op0 = strip_offset_1 (op0, inside_addr, top_compref, &off0);
-	  *offset = off0 + int_cst_value (tmp);
-	  return op0;
-	}
+	if (!inside_addr)
+	  return orig_expr;
+
+	tmp = component_ref_field_offset (expr);
+	field = TREE_OPERAND (expr, 1);
+	if (top_compref
+	    && cst_and_fits_in_hwi (tmp)
+	    && cst_and_fits_in_hwi (DECL_FIELD_BIT_OFFSET (field)))
+	  {
+	    HOST_WIDE_INT boffset, abs_off;
+
+	    /* Strip the component reference completely.  */
+	    op0 = TREE_OPERAND (expr, 0);
+	    op0 = strip_offset_1 (op0, inside_addr, top_compref, &off0);
+	    boffset = int_cst_value (DECL_FIELD_BIT_OFFSET (field));
+	    abs_off = abs_hwi (boffset) / BITS_PER_UNIT;
+	    if (boffset < 0)
+	      abs_off = -abs_off;
+
+	    *offset = off0 + int_cst_value (tmp) + abs_off;
+	    return op0;
+	  }
+      }
       break;
 
     case ADDR_EXPR:
@@ -2182,7 +2195,10 @@ strip_offset_1 (tree expr, bool inside_addr, bool top_compref,
 static tree
 strip_offset (tree expr, unsigned HOST_WIDE_INT *offset)
 {
-  return strip_offset_1 (expr, false, false, offset);
+  HOST_WIDE_INT off;
+  tree core = strip_offset_1 (expr, false, false, &off);
+  *offset = off;
+  return core;
 }
 
 /* Returns variant of TYPE that can be used as base for different uses.