Add option to dump Pre-SSA Liveness calculation

Author: dibyendumajumdar

optvm/src/main/java/com/compilerprogramming/ezlang/compiler/EnterSSA.java

@@ -48,6 +48,10 @@ public EnterSSA(CompiledFunction bytecodeFunction, EnumSet<Options> options) {
         this.blocks = domTree.blocks;   // the blocks are ordered reverse post order
         findNonLocalNames();
         new Liveness(bytecodeFunction); // EWe require liveness info to construct pruned ssa
+        if (options.contains(Options.DUMP_PRE_SSA_LIVENESS)) {
+            System.out.println("Pre SSA Liveness");
+            System.out.println(bytecodeFunction.toStr(new StringBuilder(), true));
+        }
         insertPhis();
         renameVars();
         bytecodeFunction.isSSA = true;

optvm/src/main/java/com/compilerprogramming/ezlang/compiler/Options.java

@@ -11,6 +11,7 @@ public enum Options {
     DUMP_INITIAL_IR,
     DUMP_PRE_SSA_DOMTREE,
     DUMP_PRE_SSA_DOMFRONTIERS,
+    DUMP_PRE_SSA_LIVENESS,
     DUMP_SSA_IR,
     DUMP_SCCP_PREAPPLY,
     DUMP_SCCP_POSTAPPLY,