removed C99 constructs

[libfirm] / ir / ana / irscc.c

diff --git a/ir/ana/irscc.c b/ir/ana/irscc.c
index 33ef70b..c15c722 100644 (file)
--- a/ir/ana/irscc.c
+++ b/ir/ana/irscc.c
@@ -17,7 +17,11 @@
 #include "config.h"
 #endif
 
+#ifdef HAVE_STRING_H
 #include <string.h>
+#endif
+
+#include <stdlib.h>
 
 #include "irloop_t.h"
 
@@ -487,6 +491,10 @@ void *get_loop_link (const ir_loop *loop) {
 #endif
 }
 
+int is_ir_loop(const void *thing) {
+  return (get_kind(thing) == k_ir_loop);
+}
+
 /* The outermost loop is remarked in the surrounding graph. */
 void     set_irg_loop(ir_graph *irg, ir_loop *loop) {
   assert(irg);
@@ -508,32 +516,6 @@ static INLINE void
 init_node (ir_node *n, void *env) {
   set_irn_link (n, new_scc_info());
   clear_backedges(n);
-#if 0
-  /* Also init nodes not visible in intraproc_view. */
-    /* @@@ init_node is called for too many nodes -- this wastes memory!.
-       The mem is not lost as its on the obstack. */
-  if (get_irn_op(n) == op_Filter) {
-    for (i = 0; i < get_Filter_n_cg_preds(n); i++)
-      init_node(get_Filter_cg_pred(n, i), NULL);
-  }
-  if (get_irn_op(n) == op_Block) {
-    for (i = 0; i < get_Block_cg_n_cfgpreds(n); i++) {
-      init_node(get_Block_cg_cfgpred(n, i), NULL);
-    }
-  }
-  /* The following pattern matches only after a call from above pattern. */
-  if ((get_irn_op(n) == op_Proj) /*&& (get_Proj_proj(n) == 0)*/) {
-    /* @@@ init_node is called for every proj -- this wastes memory!.
-       The mem is not lost as its on the obstack. */
-    ir_node *cb = get_Proj_pred(n);
-    if ((get_irn_op(cb) == op_CallBegin) ||
-    (get_irn_op(cb) == op_EndReg) ||
-    (get_irn_op(cb) == op_EndExcept)) {
-      init_node(cb, NULL);
-      init_node(get_nodes_block(cb), NULL);
-    }
-  }
-#endif
 }
 
 static INLINE void
@@ -1444,3 +1426,37 @@ void find_strange_loop_nodes(ir_loop *l) {
   if (found_problem) exit(0);
 
 }
+
+/* ------------------------------------------------------------------- */
+/* Simple analyses based on the loop information                       */
+/* ------------------------------------------------------------------- */
+
+int is_loop_variant(ir_loop *l, ir_loop *b) {
+  int i, n_elems;
+
+  if (l == b) return true;
+
+  n_elems = get_loop_n_elements(l);
+  for (i = 0; i < n_elems; ++i) {
+    loop_element e = get_loop_element(l, i);
+    if (is_ir_loop(e.kind))
+      if (is_loop_variant(e.son, b))
+        return true;
+  }
+
+  return false;
+}
+
+/* Test whether a value is loop invariant.
+ *
+ * @param n      The node to be tested.
+ * @param block  A block node.  We pass the block, not the loop as we must
+ *               start off with a block loop to find all proper uses.
+ *
+ * Returns true, if the node n is not changed in the loop block
+ * belongs to or in inner loops of this block. */
+int is_loop_invariant(ir_node *n, ir_node *block) {
+  ir_loop *l = get_irn_loop(block);
+  ir_node *b = (is_Block(n)) ? n : get_nodes_block(n);
+  return !is_loop_variant(l, get_irn_loop(b));
+}