[PATCH] Simplify gimple_assign_load

[Richard Biener <rguenther@suse.de>]

The following simplifies and outlines gimple_assign_load.  In
particular it is not necessary to get at the base of the possibly
loaded expression but just handle the case of a single handled
component wrapping a non-memory operand.

Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.

	* gimple.h (gimple_assign_load): Outline...
	* gimple.cc (gimple_assign_load): ... here.  Avoid
	get_base_address and instead just strip the outermost
	handled component, treating a remaining handled component
	as load.
---
 gcc/gimple.cc | 20 ++++++++++++++++++++
 gcc/gimple.h  | 18 +-----------------
 2 files changed, 21 insertions(+), 17 deletions(-)

diff --git a/gcc/gimple.cc b/gcc/gimple.cc
index 5e4eda417fb..e0ba42add39 100644
--- a/gcc/gimple.cc
+++ b/gcc/gimple.cc
@@ -1788,6 +1788,26 @@ gimple_assign_unary_nop_p (gimple *gs)
               == TYPE_MODE (TREE_TYPE (gimple_assign_rhs1 (gs)))));
 }
 
+/* Return true if GS is an assignment that loads from its rhs1.  */
+
+bool
+gimple_assign_load_p (const gimple *gs)
+{
+  tree rhs;
+  if (!gimple_assign_single_p (gs))
+    return false;
+  rhs = gimple_assign_rhs1 (gs);
+  if (TREE_CODE (rhs) == WITH_SIZE_EXPR)
+    return true;
+  if (handled_component_p (rhs))
+    rhs = TREE_OPERAND (rhs, 0);
+  return (handled_component_p (rhs)
+	  || DECL_P (rhs)
+	  || TREE_CODE (rhs) == MEM_REF
+	  || TREE_CODE (rhs) == TARGET_MEM_REF);
+}
+
+
 /* Set BB to be the basic block holding G.  */
 
 void
diff --git a/gcc/gimple.h b/gcc/gimple.h
index 081d18e425a..daf55242f68 100644
--- a/gcc/gimple.h
+++ b/gcc/gimple.h
@@ -1629,6 +1629,7 @@ tree gimple_call_nonnull_arg (gcall *);
 bool gimple_assign_copy_p (gimple *);
 bool gimple_assign_ssa_name_copy_p (gimple *);
 bool gimple_assign_unary_nop_p (gimple *);
+bool gimple_assign_load_p (const gimple *);
 void gimple_set_bb (gimple *, basic_block);
 void gimple_assign_set_rhs_from_tree (gimple_stmt_iterator *, tree);
 void gimple_assign_set_rhs_with_ops (gimple_stmt_iterator *, enum tree_code,
@@ -2952,23 +2953,6 @@ gimple_store_p (const gimple *gs)
   return lhs && !is_gimple_reg (lhs);
 }
 
-/* Return true if GS is an assignment that loads from its rhs1.  */
-
-inline bool
-gimple_assign_load_p (const gimple *gs)
-{
-  tree rhs;
-  if (!gimple_assign_single_p (gs))
-    return false;
-  rhs = gimple_assign_rhs1 (gs);
-  if (TREE_CODE (rhs) == WITH_SIZE_EXPR)
-    return true;
-  rhs = get_base_address (rhs);
-  return (DECL_P (rhs)
-	  || TREE_CODE (rhs) == MEM_REF || TREE_CODE (rhs) == TARGET_MEM_REF);
-}
-
-
 /* Return true if S is a type-cast assignment.  */
 
 inline bool
-- 
2.35.3