Generate code for loops formed with the new builder

Adapt the existing counted loop analysis and range/null check
elimination code to work with the new loop building heuristics.
Cleaned up the old ad-hoc loop builder.

Suspend polling is enabled by default for loops. The backward chaining
cell will be used in self-verification and profiling mode.

If the loop includes accesses to resolved fields/classes, abort code
generation for now and revert to the basic acyclic trace. Added
tests/090-loop-formation to make sure the JIT won't choke on such
instructions.

Change-Id: Idbc57df0a745be3b692f68c1acb6d4861c537f75
diff --git a/vm/compiler/Loop.h b/vm/compiler/Loop.h
index ec87e57..122817d 100644
--- a/vm/compiler/Loop.h
+++ b/vm/compiler/Loop.h
@@ -36,4 +36,13 @@
 
 bool dvmCompilerFilterLoopBlocks(CompilationUnit *cUnit);
 
+/*
+ * An unexecuted code path may contain unresolved fields or classes. Before we
+ * have a quiet resolver we simply bail out of the loop compilation mode.
+ */
+#define BAIL_LOOP_COMPILATION() if (cUnit->jitMode == kJitLoop) {       \
+                                    cUnit->quitLoopMode = true;         \
+                                    return false;                       \
+                                }
+
 #endif /* _DALVIK_VM_LOOP */