Adds 'Initialize' Wyrd instruction.

The 'SetValue' Wyrd instruction is no longer allowed to write to a
non-existing memory element.

10 files changed, 277 insertions, 37 deletions

diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/Compiler.java b/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/Compiler.java
index 4fbe4fe..3b57ff3 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/Compiler.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/Compiler.java
@@ -1,9 +1,15 @@
 package tonkadur.wyrd.v1.compiler.fate.v1;
 
+import java.util.List;
+import java.util.ArrayList;
+
 import tonkadur.wyrd.v1.compiler.util.registers.RegisterManager;
 import tonkadur.wyrd.v1.compiler.util.InstructionManager;
 
 import tonkadur.wyrd.v1.lang.type.DictType;
+import tonkadur.wyrd.v1.lang.type.Type;
+
+import tonkadur.wyrd.v1.lang.meta.Instruction;
 
 import tonkadur.wyrd.v1.lang.Register;
 import tonkadur.wyrd.v1.lang.World;
@@ -26,14 +32,20 @@ public class Compiler
 
       compiler = new Compiler(wyrd_world);
 
+      compiler.assembler().handle_adding_instruction
+      (
+         compiler.assembler().merge(compiler.registers().pop_initializes()),
+         wyrd_world
+      );
+
       compiler.compile_extensions(fate_world);
       compiler.compile_types(fate_world);
       compiler.compile_variables(fate_world);
 
-      compiler.compile_main_sequence(fate_world);
-
       compiler.compile_sequences(fate_world);
 
+      compiler.compile_main_sequence(fate_world);
+
       compiler.add_registers();
 
       return compiler.wyrd_world;
@@ -80,23 +92,30 @@ public class Compiler
    )
    throws Throwable
    {
+      final List<Instruction> init_instr;
+
+      init_instr = new ArrayList<Instruction>();
+
       for
       (
          final tonkadur.fate.v1.lang.Variable variable:
             fate_world.variables().get_all()
       )
       {
+         final Type t;
          final Register r;
 
-         r =
-            registers.register
-            (
-               TypeCompiler.compile(this, variable.get_type()),
-               variable.get_name()
-            );
+         t = TypeCompiler.compile(this, variable.get_type());
+         r = registers.register(t, variable.get_name());
 
          r.set_is_in_use(true);
       }
+
+      this.assembler().handle_adding_instruction
+      (
+         this.assembler().merge(init_instr),
+         this.world()
+      );
    }
 
    protected void compile_sequences
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/InstructionCompiler.java b/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/InstructionCompiler.java
index 55ff4a2..67a7e0d 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/InstructionCompiler.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/InstructionCompiler.java
@@ -33,9 +33,10 @@ import tonkadur.wyrd.v1.lang.instruction.Assert;
 import tonkadur.wyrd.v1.lang.instruction.Display;
 import tonkadur.wyrd.v1.lang.instruction.End;
 import tonkadur.wyrd.v1.lang.instruction.EventCall;
-import tonkadur.wyrd.v1.lang.instruction.Remove;
-import tonkadur.wyrd.v1.lang.instruction.PromptString;
+import tonkadur.wyrd.v1.lang.instruction.Initialize;
 import tonkadur.wyrd.v1.lang.instruction.PromptInteger;
+import tonkadur.wyrd.v1.lang.instruction.PromptString;
+import tonkadur.wyrd.v1.lang.instruction.Remove;
 import tonkadur.wyrd.v1.lang.instruction.ResolveChoices;
 import tonkadur.wyrd.v1.lang.instruction.SetPC;
 import tonkadur.wyrd.v1.lang.instruction.SetValue;
@@ -210,7 +211,7 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
 
       result.add
       (
-         new SetValue
+         new Initialize
          (
             new RelativeAddress
             (
@@ -222,6 +223,28 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
                ),
                element_compiler.get_computation().get_type()
             ),
+            element_compiler.get_computation().get_type()
+         )
+      );
+
+      result.add
+      (
+         new SetValue
+         (
+            new RelativeAddress
+            (
+               collection_as_address,
+               new Cast
+               (
+                  Operation.minus
+                  (
+                     new Size(collection_as_address),
+                     Constant.ONE
+                  ),
+                  Type.STRING
+               ),
+               element_compiler.get_computation().get_type()
+            ),
             element_compiler.get_computation()
          )
       );
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/SequenceCompiler.java b/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/SequenceCompiler.java
index cf23045..16f7ec0 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/SequenceCompiler.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/SequenceCompiler.java
@@ -9,6 +9,7 @@ import tonkadur.wyrd.v1.lang.World;
 import tonkadur.wyrd.v1.lang.Register;
 
 import tonkadur.wyrd.v1.lang.instruction.SetValue;
+import tonkadur.wyrd.v1.lang.instruction.SetPC;
 
 import tonkadur.wyrd.v1.lang.computation.Constant;
 public class SequenceCompiler
@@ -26,6 +27,7 @@ public class SequenceCompiler
       final List<Instruction> init_instructions;
       final List<Register> parameters;
       final List<Register> to_be_cleaned;
+      final String end_of_sequence;
       final InstructionCompiler ic;
 
       init_instructions = new ArrayList<Instruction>();
@@ -33,6 +35,7 @@ public class SequenceCompiler
       to_be_cleaned = new ArrayList<Register>();
       ic = new InstructionCompiler(compiler);
 
+      end_of_sequence = compiler.assembler().generate_label("<sequence#end>");
 
       compiler.world().add_sequence_label
       (
@@ -42,7 +45,15 @@ public class SequenceCompiler
 
       compiler.assembler().add_fixed_name_label(fate_sequence.get_name());
 
-      compiler.registers().create_stackable_context(fate_sequence.get_name());
+      compiler.registers().create_stackable_context
+      (
+         fate_sequence.get_name()
+      );
+
+      init_instructions.add
+      (
+         new SetPC(compiler.assembler().get_label_constant(end_of_sequence))
+      );
 
       init_instructions.add
       (
@@ -109,7 +120,17 @@ public class SequenceCompiler
 
       compiler.assembler().handle_adding_instruction
       (
-         compiler.assembler().merge(init_instructions),
+         compiler.assembler().merge(compiler.registers().pop_initializes()),
+         compiler.world()
+      );
+
+      compiler.assembler().handle_adding_instruction
+      (
+         compiler.assembler().mark_after
+         (
+            compiler.assembler().merge(init_instructions),
+            end_of_sequence
+         ),
          compiler.world()
       );
    }
@@ -146,6 +167,12 @@ public class SequenceCompiler
 
       compiler.assembler().handle_adding_instruction
       (
+         compiler.assembler().merge(compiler.registers().pop_initializes()),
+         compiler.world()
+      );
+
+      compiler.assembler().handle_adding_instruction
+      (
          ic.get_result(),
          compiler.world()
       );
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/FunctionContext.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/FunctionContext.java
deleted file mode 100644
index e69de29..0000000
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/FunctionContext.java
+++ /dev/null
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/InsertAt.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/InsertAt.java
index 7894330..12e4658 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/InsertAt.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/util/InsertAt.java
@@ -19,6 +19,7 @@ import tonkadur.wyrd.v1.lang.computation.RelativeAddress;
 import tonkadur.wyrd.v1.lang.computation.ValueOf;
 
 import tonkadur.wyrd.v1.lang.instruction.SetValue;
+import tonkadur.wyrd.v1.lang.instruction.Initialize;
 
 import tonkadur.wyrd.v1.compiler.util.registers.RegisterManager;
 
@@ -73,9 +74,29 @@ public class InsertAt
 
       value_of_index = new ValueOf(index);
 
+
       /* (set .end collection_size) */
       result.add(new SetValue(end.get_address(), collection_size));
 
+      /*
+       * Increasing the size of the list by one.
+       * This *does* increase the value of collection_size, so don't do it
+       * before setting .end.
+       */
+      result.add
+      (
+         new Initialize
+         (
+            new RelativeAddress
+            (
+               collection,
+               new Cast(collection_size, Type.STRING),
+               element_type
+            ),
+            element_type
+         )
+      );
+
       /* (set .prev (- (val .end) 1)) */
       while_body.add
       (
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/registers/RegisterContext.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/registers/RegisterContext.java
index 1baabb7..c0d70a3 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/registers/RegisterContext.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/util/registers/RegisterContext.java
@@ -14,6 +14,8 @@ import tonkadur.wyrd.v1.lang.Register;
 
 import tonkadur.wyrd.v1.lang.type.Type;
 
+import tonkadur.wyrd.v1.lang.instruction.Initialize;
+
 class RegisterContext
 {
    protected static final String default_name_prefix = ".anon.";
@@ -61,7 +63,11 @@ class RegisterContext
       return register_by_name.values();
    }
 
-   public Register reserve (final Type t)
+   public Register reserve
+   (
+      final Type t,
+      final List<Instruction> initialize_holder
+   )
    {
       final String name;
       final Register result;
@@ -88,7 +94,7 @@ class RegisterContext
 
       name = (name_prefix + Integer.toString(generated_registers++));
 
-      result = create_register(t, name);
+      result = create_register(t, name, initialize_holder);
 
       result.set_is_in_use(true);
 
@@ -99,11 +105,16 @@ class RegisterContext
       return result;
    }
 
-   public Register reserve (final Type t, final String name)
+   public Register reserve
+   (
+      final Type t,
+      final String name,
+      final List<Instruction> initialize_holder
+   )
    {
       final Register result;
 
-      result = create_register(t, name);
+      result = create_register(t, name, initialize_holder);
 
       if (register_by_name.get(name) != null)
       {
@@ -191,9 +202,20 @@ class RegisterContext
       r.set_is_in_use(false);
    }
 
-   protected Register create_register (final Type t, final String name)
+   protected Register create_register
+   (
+      final Type t,
+      final String name,
+      final List<Instruction> initialize_holder
+   )
    {
-      return new Register(t, name);
+      final Register result;
+
+      result = new Register(t, name);
+
+      initialize_holder.add(new Initialize(result.get_address(), t));
+
+      return result;
    }
 
    public List<Instruction> get_finalize_instructions ()
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/registers/RegisterManager.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/registers/RegisterManager.java
index 653fcbe..07ea1ac 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/registers/RegisterManager.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/util/registers/RegisterManager.java
@@ -23,9 +23,10 @@ import tonkadur.wyrd.v1.lang.computation.Cast;
 import tonkadur.wyrd.v1.lang.computation.ValueOf;
 import tonkadur.wyrd.v1.lang.computation.Size;
 
-import tonkadur.wyrd.v1.lang.instruction.SetValue;
-import tonkadur.wyrd.v1.lang.instruction.SetPC;
+import tonkadur.wyrd.v1.lang.instruction.Initialize;
 import tonkadur.wyrd.v1.lang.instruction.Remove;
+import tonkadur.wyrd.v1.lang.instruction.SetPC;
+import tonkadur.wyrd.v1.lang.instruction.SetValue;
 
 import tonkadur.wyrd.v1.lang.type.Type;
 import tonkadur.wyrd.v1.lang.type.MapType;
@@ -39,19 +40,22 @@ public class RegisterManager
    protected final RegisterContext base_context, parameter_context;
    protected final Register next_pc, pc_stack;
    protected final Register choice_number, rand_mode, rand_value;
+   protected List<Instruction> awaiting_inits;
    protected int created_contexts;
 
    public RegisterManager ()
    {
+      awaiting_inits = new ArrayList<Instruction>();
       base_context = new RegisterContext("base context");
       parameter_context = new RegisterContext("parameter context", ".param.");
 
-      next_pc = base_context.reserve(Type.INT);
-      pc_stack = base_context.reserve(new MapType(Type.INT));
+      next_pc = base_context.reserve(Type.INT, awaiting_inits);
+      pc_stack = base_context.reserve(new MapType(Type.INT), awaiting_inits);
 
-      choice_number = base_context.reserve(Type.INT);
-      rand_mode = base_context.reserve(Type.INT);
-      rand_value = base_context.reserve(new MapType(Type.INT));
+      choice_number = base_context.reserve(Type.INT, awaiting_inits);
+      rand_mode = base_context.reserve(Type.INT, awaiting_inits);
+      rand_value =
+         base_context.reserve(new MapType(Type.INT), awaiting_inits);
 
       context_by_name = new HashMap<String, StackableRegisterContext>();
       context = new ArrayDeque<RegisterContext>();
@@ -62,7 +66,7 @@ public class RegisterManager
 
    public Register reserve (final Type t)
    {
-      return context.peekFirst().reserve(t);
+      return context.peekFirst().reserve(t, awaiting_inits);
    }
 
    public void release (final Register r)
@@ -94,7 +98,13 @@ public class RegisterManager
    {
       final StackableRegisterContext result;
 
-      result = new StackableRegisterContext(base_context, context_name);
+      result =
+         new StackableRegisterContext
+         (
+            base_context,
+            context_name,
+            awaiting_inits
+         );
 
       if (context_by_name.containsKey(context_name))
       {
@@ -130,7 +140,7 @@ public class RegisterManager
 
    public Register register (final Type t, final String name)
    {
-      return context.peekFirst().reserve(t, name);
+      return context.peekFirst().reserve(t, name, awaiting_inits);
    }
 
    public void bind (final String name, final Register register)
@@ -169,7 +179,7 @@ public class RegisterManager
 
       result.add
       (
-         new SetValue
+         new Initialize
          (
             new RelativeAddress
             (
@@ -177,6 +187,27 @@ public class RegisterManager
                new Cast(new Size(pc_stack.get_address()), Type.STRING),
                Type.INT
             ),
+            Type.INT
+         )
+      );
+
+      result.add
+      (
+         new SetValue
+         (
+            new RelativeAddress
+            (
+               pc_stack.get_address(),
+               new Cast
+               (
+                  Operation.minus
+                  (
+                     new Size(pc_stack.get_address()),
+                     Constant.ONE
+                  ), Type.STRING
+               ),
+               Type.INT
+            ),
             leave_to
          )
       );
@@ -294,7 +325,7 @@ public class RegisterManager
       {
          final Register r;
 
-         r = parameter_context.reserve(p.get_type());
+         r = parameter_context.reserve(p.get_type(), awaiting_inits);
 
          result.add(new SetValue(r.get_address(), p));
 
@@ -322,7 +353,7 @@ public class RegisterManager
       {
          final Register r;
 
-         r = parameter_context.reserve(p.get_type());
+         r = parameter_context.reserve(p.get_type(), awaiting_inits);
 
          result.add(new SetValue(p.get_address(), r.get_value()));
 
@@ -337,4 +368,15 @@ public class RegisterManager
 
       return result;
    }
+
+   public List<Instruction> pop_initializes ()
+   {
+      final List<Instruction> result;
+
+      result = awaiting_inits;
+
+      awaiting_inits = new ArrayList<Instruction>();
+
+      return result;
+   }
 }
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/registers/StackableRegisterContext.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/registers/StackableRegisterContext.java
index 973806a..8731d8c 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/registers/StackableRegisterContext.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/util/registers/StackableRegisterContext.java
@@ -23,6 +23,7 @@ import tonkadur.wyrd.v1.lang.computation.ValueOf;
 
 import tonkadur.wyrd.v1.lang.instruction.SetValue;
 import tonkadur.wyrd.v1.lang.instruction.Remove;
+import tonkadur.wyrd.v1.lang.instruction.Initialize;
 
 import tonkadur.wyrd.v1.lang.type.Type;
 import tonkadur.wyrd.v1.lang.type.PointerType;
@@ -43,7 +44,8 @@ class StackableRegisterContext extends RegisterContext
    public StackableRegisterContext
    (
       final RegisterContext base_context,
-      final String context_name
+      final String context_name,
+      final List<Instruction> initialize_holder
    )
    {
       super(context_name);
@@ -54,11 +56,12 @@ class StackableRegisterContext extends RegisterContext
 
       context_structure = new DictType(context_name, context_structure_fields);
 
-      context_stack_level = base_context.reserve(Type.INT);
+      context_stack_level = base_context.reserve(Type.INT, initialize_holder);
       context_stacks =
          base_context.reserve
          (
-            new MapType(new PointerType(context_structure))
+            new MapType(new PointerType(context_structure)),
+            initialize_holder
          );
 
       current_context_address_holder =
@@ -78,7 +81,12 @@ class StackableRegisterContext extends RegisterContext
    }
 
    @Override
-   protected Register create_register (final Type t, final String name)
+   protected Register create_register
+   (
+      final Type t,
+      final String name,
+      final List<Instruction> initialize_holder
+   )
    {
       final Register result;
 
@@ -96,7 +104,7 @@ class StackableRegisterContext extends RegisterContext
 
       context_structure.get_fields().put(name, t);
 
-      return
+      result =
          new Register
          (
             new RelativeAddress
@@ -108,6 +116,11 @@ class StackableRegisterContext extends RegisterContext
             t,
             name
          );
+
+      /* No need for this: it's part of the type. */
+      //initialize_holder.add(new Initialize(result.get_address(), t));
+
+      return result;
    }
 
    public List<Instruction> get_initialize_instructions ()
@@ -127,6 +140,15 @@ class StackableRegisterContext extends RegisterContext
 
       result.add
       (
+         new Initialize
+         (
+            current_context_address_holder,
+            new PointerType(context_structure)
+         )
+      );
+
+      result.add
+      (
          new SetValue
          (
             current_context_address_holder,
diff --git a/src/core/src/tonkadur/wyrd/v1/lang/instruction/Initialize.java b/src/core/src/tonkadur/wyrd/v1/lang/instruction/Initialize.java
new file mode 100644
index 0000000..04a039e
--- /dev/null
+++ b/src/core/src/tonkadur/wyrd/v1/lang/instruction/Initialize.java
@@ -0,0 +1,61 @@
+package tonkadur.wyrd.v1.lang.instruction;
+
+import tonkadur.wyrd.v1.lang.computation.Address;
+
+import tonkadur.wyrd.v1.lang.type.Type;
+import tonkadur.wyrd.v1.lang.meta.Instruction;
+import tonkadur.wyrd.v1.lang.meta.InstructionVisitor;
+
+public class Initialize extends Instruction
+{
+   /***************************************************************************/
+   /**** MEMBERS **************************************************************/
+   /***************************************************************************/
+   protected final Address address;
+   protected final Type type;
+
+   /***************************************************************************/
+   /**** PUBLIC ***************************************************************/
+   /***************************************************************************/
+   /**** Constructors *********************************************************/
+   public Initialize (final Address address, final Type type)
+   {
+      this.address = address;
+      this.type = type;
+   }
+
+   /**** Accessors ************************************************************/
+   public Address get_address ()
+   {
+      return address;
+   }
+
+   public Type get_type ()
+   {
+      return type;
+   }
+
+   @Override
+   public void get_visited_by (final InstructionVisitor iv)
+   throws Throwable
+   {
+      iv.visit_initialize(this);
+   }
+
+   /**** Misc. ****************************************************************/
+   @Override
+   public String toString ()
+   {
+      final StringBuilder sb;
+
+      sb = new StringBuilder();
+
+      sb.append("(Initialize ");
+      sb.append(address.toString());
+      sb.append(" ");
+      sb.append(type.toString());
+      sb.append(")");
+
+      return sb.toString();
+   }
+}
diff --git a/src/core/src/tonkadur/wyrd/v1/lang/meta/InstructionVisitor.java b/src/core/src/tonkadur/wyrd/v1/lang/meta/InstructionVisitor.java
index 63ca737..72a4cd4 100644
--- a/src/core/src/tonkadur/wyrd/v1/lang/meta/InstructionVisitor.java
+++ b/src/core/src/tonkadur/wyrd/v1/lang/meta/InstructionVisitor.java
@@ -36,4 +36,7 @@ public interface InstructionVisitor
 
    public void visit_set_value (final SetValue n)
    throws Throwable;
+
+   public void visit_initialize (final Initialize n)
+   throws Throwable;
 }