2007-04-16 H.J. Lu <hongjiu.lu@intel.com>

[pf3gnuchains/gcc-fork.git] / gcc / tree-ssa-threadedge.c

diff --git a/gcc/tree-ssa-threadedge.c b/gcc/tree-ssa-threadedge.c
index 777685a..86b2656 100644 (file)
--- a/gcc/tree-ssa-threadedge.c
+++ b/gcc/tree-ssa-threadedge.c
@@ -488,7 +488,19 @@ simplify_control_stmt_condition (edge e,
    Note it is quite common for the first block inside a loop to
    end with a conditional which is either always true or always
    false when reached via the loop backedge.  Thus we do not want
-   to blindly disable threading across a loop backedge.  */
+   to blindly disable threading across a loop backedge.
+ 
+   DUMMY_COND is a shared cond_expr used by condition simplification as scratch,
+   to avoid allocating memory.
+ 
+   HANDLE_DOMINATING_ASSERTS is true if we should try to replace operands of
+   the simplified condition with left-hand sides of ASSERT_EXPRs they are
+   used in.
+ 
+   STACK is used to undo temporary equivalences created during the walk of
+   E->dest.
+
+   SIMPLIFY is a pass-specific function used to simplify statements.  */
 
 void
 thread_across_edge (tree dummy_cond,