Eliminate two instructions per QAST::WVal.

This passes the values directly to the indy bootstrap method, which we
didn't have the infrastructure to do when QAST::WVal stuff was first
switched over.

Author: jnthn

src/vm/jvm/QAST/Compiler.nqp

@@ -3476,12 +3476,14 @@ class QAST::CompilerJAST {
         my $handle := nqp::scgethandle($sc);
         my $idx    := nqp::scgetobjidx($sc, $val);
         my $il     := JAST::InstructionList.new();
-        $il.append(JAST::PushSVal.new( :value($handle) ));
-        $il.append(JAST::PushIVal.new( :value($idx) ));
         $il.append(JAST::Instruction.new( :op('aload_1') ));
         $il.append(JAST::InvokeDynamic.new(
-            'wval', $TYPE_SMO, [$TYPE_STR, 'J', $TYPE_TC],
-            'org/perl6/nqp/runtime/IndyBootstrap', 'wval'
+            'wval', $TYPE_SMO, [$TYPE_TC],
+            'org/perl6/nqp/runtime/IndyBootstrap', 'wval',
+            [
+                JAST::PushSVal.new( :value($handle) ),
+                JAST::PushIVal.new( :value($idx) )
+            ]
         ));
         result($il, $RT_OBJ);
     }

src/vm/jvm/runtime/org/perl6/nqp/runtime/IndyBootstrap.java

@@ -41,6 +41,42 @@ public static SixModelObject wvalResolve(MutableCallSite cs, String sc, long idx
         return res;
     }
 
+    public static CallSite wval(Lookup caller, String name, MethodType type,
+            String sc, long idx) {
+        try {
+            /* Look up wval resolver method. */
+            MethodType resType = MethodType.methodType(SixModelObject.class,
+                    String.class, long.class, MutableCallSite.class, ThreadContext.class);
+            MethodHandle res = caller.findStatic(IndyBootstrap.class, "wvalResolve", resType);
+            
+            /* Create a mutable callsite, and curry the resolver with it. */
+            MutableCallSite cs = new MutableCallSite(type);
+            cs.setTarget(MethodHandles.insertArguments(res, 0, sc, idx, cs));
+            
+            /* Produce callsite; it'll be updated with the resolved WVal upon the
+             * first invocation. */
+            return cs;
+        }
+        catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+    
+    public static SixModelObject wvalResolve(String sc, long idx, MutableCallSite cs, ThreadContext tc) {
+        /* Look up the WVal. */
+        SixModelObject res = tc.gc.scs.get(sc).root_objects.get((int)idx);
+        
+        /* Update this callsite, so that we never run the lookup again and instead
+         * just always use the resolved object. Discards incoming arguments, as
+         * they are no longer needed. */
+        cs.setTarget(MethodHandles.dropArguments(
+                MethodHandles.constant(SixModelObject.class, res),
+                0, ThreadContext.class));
+        
+        /* Hand back the resulting object, for this first call. */
+        return res;
+    }
+    
     public static CallSite subcall(Lookup caller, String _, MethodType type, String name, int csIdx) {
         try {
             /* Look up subcall resolver method. */