string literal initial

UnitNodes.py

 from AST import ASTNode, getParseTreeNodes
 from Environment import Env
 from TheTypeNode import TypeNode, TypeStruct
-from CodeGenUtils import p, getLStringLabel
+from CodeGenUtils import p, getLStringLabel, importHelper
 
 #   LiteralNode
 #   ParamNode
@@ -61,14 +61,66 @@ class LiteralNode(ASTNode):
             return
 
         # string TODO
-        # if self.name == 'java.lang.String':
-        #     n = getLStringLabel()
-        #     lStringLabel = "_literalstring" + n
-
-        #     self.code += p(lStringLabel + ":", "")
-        #     self.code += p("db", str(self.getConstant()))
-        #     self.code += p("mov", "eax", "[" + lStringLabel + "]", " set to literal string")
-        #     return
+        if self.name == 'java.lang.String':
+            self.code += ";Start of String Literal Creation for class " + self.typeName + "\n"
+            # generate array of characters
+            # then call new String(array)
+
+            # FIRST: create char array for this string TODO figure out how to populate this array
+            # 1. Allocating space for the char array in heap
+            # Note: uses ecx to temporarily store the array length
+            self.code += ";Start of char array creation\n" + \
+                p(instruction="push", arg1="eax", arg2=str(len(self.value)), comment="array length") + \
+                p(instruction="push", arg1="ecx", comment="saving ecx's value") + \
+                p(instruction="mov", arg1="ecx", arg2="eax", comment="ecx now stroes the array's length") + \
+                p(instruction="add", arg1="eax", arg2=2, comment="number of items to allocate on heap") + \
+                p(instruction="imul", arg1="eax", arg2=4, comment="number of bytes to allocate on heap") + \
+                p(instruction="call", arg1="__malloc", comment="allocating memory for array on heap")
+
+            # 2. Pointing first item to vtable
+            aLabel = "A_char"
+            self.code += p(instruction="extern", arg1=aLabel) + \
+                p(instruction="mov", arg1="[eax]", arg2="dword "+aLabel, comment="first item is vtable pointer")
+            
+            # 3. Storing length in the second slot
+            self.code += p(instruction="mov", arg1="[eax+4]", arg2="ecx", comment="storing array length in second slot")
+
+            # 4. Restoring ecx
+            self.code += p(instruction="pop", arg1="ecx", comment="restoring register ecx")
+            self.code += ";End of char array creation\n"
+
+            # SECOND: create new string object with the char array 
+
+            # 1. alloc enough space for this object
+            classDef = self.env.getNode('java.lang.String', 'type')
+            fieldOffset = classDef.fieldOffset
+            numFields = len(fieldOffset)
+            numBytes = (numFields + 1) * 4
+            self.code += "; Creating an object for class " + self.typeName + "\n"
+            self.code += p(instruction="mov", arg1="eax", arg2=numBytes, comment="allocating memory for object") + \
+                         p(instruction="call", arg1="__malloc")
+
+            # 2. Pointing first item to vtable
+            self.code += importHelper(classDef.name, self.typeName, "C_"+classDef.name)
+            self.code += p(instruction="mov", arg1="[eax]", arg2="dword C_" + classDef.name, comment="first item is vtable pointer")
+
+            # 3. Calling constructor
+            self.code += "; Calling constructor for String\n"
+            self.code += p(instruction="push", arg1="eax", comment="pushing object as first argument")
+            # Evaluate arguments and pushing parameters
+            self.code += p("mov", "eax", aLabel) # TODO this is probably wrong, where is my array I just created?
+
+            # 4. call String::String(char[] chars)
+            label = "M_String_String_char"
+            self.code += importHelper(classDef.name, self.typeName, label)
+            self.code += p(instruction="call", arg1=label, comment="Calling constructor")
+
+            # 4. Popping parameters and pointer to object
+            self.code += p(instruction="add", arg1="esp", arg2=4, comment="Popping parameters")
+            self.code += p(instruction="pop", arg1="eax", comment="eax now contains pointer to newly created object")
+            self.code += ";End of object creation\n"
+            self.code += ";End of String Literal Creation for class " + self.typeName + "\n"
+            return
 
         # null
         if self.name == 'null':