Added user defined function, function call and return statement

src/main/java/chocopy/pa3/CodeGenImpl.java

@@ -2,12 +2,44 @@ package chocopy.pa3;
 
 import chocopy.common.analysis.AbstractNodeAnalyzer;
 import chocopy.common.analysis.SymbolTable;
+import chocopy.common.astnodes.AssignStmt;
+import chocopy.common.astnodes.BinaryExpr;
+import chocopy.common.astnodes.BooleanLiteral;
+import chocopy.common.astnodes.CallExpr;
+import chocopy.common.astnodes.ClassDef;
+import chocopy.common.astnodes.ClassType;
+import chocopy.common.astnodes.CompilerError;
+import chocopy.common.astnodes.Errors;
+import chocopy.common.astnodes.Expr;
+import chocopy.common.astnodes.ExprStmt;
+import chocopy.common.astnodes.ForStmt;
+import chocopy.common.astnodes.FuncDef;
+import chocopy.common.astnodes.GlobalDecl;
+import chocopy.common.astnodes.Identifier;
+import chocopy.common.astnodes.IfExpr;
+import chocopy.common.astnodes.IfStmt;
+import chocopy.common.astnodes.IndexExpr;
+import chocopy.common.astnodes.IntegerLiteral;
+import chocopy.common.astnodes.ListExpr;
+import chocopy.common.astnodes.ListType;
+import chocopy.common.astnodes.MemberExpr;
+import chocopy.common.astnodes.MethodCallExpr;
+import chocopy.common.astnodes.NonLocalDecl;
+import chocopy.common.astnodes.NoneLiteral;
+import chocopy.common.astnodes.Program;
 import chocopy.common.astnodes.ReturnStmt;
 import chocopy.common.astnodes.Stmt;
+import chocopy.common.astnodes.StringLiteral;
+import chocopy.common.astnodes.TypedVar;
+import chocopy.common.astnodes.UnaryExpr;
+import chocopy.common.astnodes.VarDef;
+import chocopy.common.astnodes.WhileStmt;
 import chocopy.common.codegen.*;
 
 import java.util.List;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
+
 import static chocopy.common.codegen.RiscVBackend.Register.*;
 
 /**
@@ -70,16 +102,43 @@ public class CodeGenImpl extends CodeGenBase {
      */
     protected void emitUserDefinedFunction(FuncInfo funcInfo) {
         backend.emitGlobalLabel(funcInfo.getCodeLabel());
-        StmtAnalyzer stmtAnalyzer = new StmtAnalyzer(funcInfo);
         
+        
+        
+        // --- Prologue ---
+        // space for return address = 4
+        // space for control link = 4
+        // space for static link =  4
+        // space for params = num of params * 4
+        // space for locals = num of locals * 4
+        int requiredStackSpace = 4 + 4 + 4 + funcInfo.getParams().size() * 4 + funcInfo.getLocals().size() * 4;
+        backend.emitADDI(SP, SP, -requiredStackSpace, "Reserve space for stack frame.");
+        backend.emitSW(RA, SP, requiredStackSpace-4, "return address");
+        backend.emitSW(FP, SP, requiredStackSpace-8, "control link");
+        // if we want to add static link
+        //backend.emitSW(FP, SP, requiredStackSpace-12, "static link");
+        backend.emitADDI(FP, SP, requiredStackSpace, "New fp is at old SP.");
+        
+        
+        
+        // --- Function Body ---
+        // statements load all the variables that caller put on stack
+        // statements use fp to load the variables
+        // example: 0(fp) is the last variable (z) while 8(fp) is the first variable (x) 
+        // for function with 3 params f(x, y, z)
+        StmtAnalyzer stmtAnalyzer = new StmtAnalyzer(funcInfo);
         for (Stmt stmt : funcInfo.getStatements()) {
             stmt.dispatch(stmtAnalyzer);
         }
+        backend.emitJ(stmtAnalyzer.epilogue, "Jump to function epilogue");
 
-        backend.emitMV(A0, ZERO, "Returning None implicitly");
-        backend.emitLocalLabel(stmtAnalyzer.epilogue, "Epilogue");
         
-        // FIXME: {... reset fp etc. ...}
+        
+        // --- Epilogue ---
+        backend.emitLocalLabel(stmtAnalyzer.epilogue, "Epilogue");
+        backend.emitLW(RA, FP, -4, "Get return address");
+        backend.emitLW(FP, FP, -8, "Use control link to restore caller's fp");
+        backend.emitADDI(SP, SP, requiredStackSpace, "Restore stack pointer");
         backend.emitJR(RA, "Return to caller");
     }
 
@@ -136,18 +195,286 @@ public class CodeGenImpl extends CodeGenBase {
             epilogue = generateLocalLabel();
         }
 
-        // FIXME: Example of statement.
+        
+        
         @Override
         public Void analyze(ReturnStmt stmt) {
-            // FIXME: Here, we emit an instruction that does nothing. Clearly,
+        		System.out.println("*** ReturnStmt");
-            // this is wrong, and you'll have to fix it.
+    			backend.emitLW(T6, FP, 0, "Inside ReturnStmt");
-            // This is here just to demonstrate how to emit a
+//        	    Expr expr = stmt.value;
-            // RISC-V instruction.
+//        	    // All expressions should save their end result in A0
-            backend.emitMV(ZERO, ZERO, "No-op");
+//        	    expr.dispatch(this);
+        		backend.emitLW(A0, FP, 0, "Load var: " + "last");
+            return null;
+        }
+
+        
+        @Override
+        public Void analyze(CallExpr node) {
+        		System.out.println("*** CallExpr");
+    			backend.emitLW(T6, FP, 0, "Inside CallExpr: " + node.function.name);
+    			
+        		// function
+        		Identifier functionId = node.function;
+        		
+        		List<Expr> args = node.args;
+        		int spaceRequiredForArgs = (args.size() + 1)*4;
+        		//backend.emitSW(A0, SP, -4, "Put static link");
+        		for (int i = 0; i < args.size(); i++) {
+        			int argNum = i + 1;
+        			int slotNum = argNum + 1; // We have extra slot for static link
+        			Expr expr = args.get(i);
+        			expr.dispatch(this);
+        			// All expressions should save their end result in A0
+        			// So, once expr is evaluated add value inside A0 onto stack as an argument
+        			backend.emitSW(A0, SP, -4*slotNum, "Push argument " + argNum + " from left");
+        		}
+        		
+        		backend.emitADDI(SP, SP, -spaceRequiredForArgs, "Set SP to last argument.");
+        		backend.emitJAL(new Label("$"+functionId.name), "Invoke function: " + functionId.name);
+        		backend.emitADDI(SP, SP, spaceRequiredForArgs, "Set SP to stack frame top.");
             return null;
         }
         
-        // FIXME: More, of course.
+        
+        
+        @Override
+        public Void analyze(MethodCallExpr node) {
+        		System.out.println("*** MethodCallExpr");
+    			backend.emitLW(T6, FP, 0, "Inside MethodCallExpr");
+        		// function
+            return defaultAction(node);
+        }
+        
+        
+        
+        @Override
+        public Void analyze(FuncDef node) {
+        		System.out.println("*** FuncDef");
+    			backend.emitLW(T6, FP, 0, "Inside FuncDef");
+        		// function
+            return defaultAction(node);
+        }
+        
+        
+        
+        @Override
+        public Void analyze(GlobalDecl node) {
+        		System.out.println("*** GlobalDecl");
+    			backend.emitLW(T6, FP, 0, "Inside GlobalDecl");
+        		// function
+            return defaultAction(node);
+        }
+        
+        
+        
+        @Override
+        public Void analyze(NonLocalDecl node) {
+    			System.out.println("*** NonLocalDecl");
+			backend.emitLW(T6, FP, 0, "Inside NonLocalDecl");
+        		// function
+            return defaultAction(node);
+        }
+        
+        
+        
+        
+        
+        
+        
+        
+        
+        // methods below are only for testing, remove or comment them when merging
+        @Override
+        public Void analyze(AssignStmt node) {
+        	    System.out.println("+++ Inside AssignStmt");
+    			backend.emitLW(T6, FP, 0, "Inside AssignStmt");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(BinaryExpr node) {
+        		System.out.println("+++ Inside BinaryExpr");
+    			backend.emitLW(T6, FP, 0, "Inside BinaryExpr");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(BooleanLiteral node) {
+    			System.out.println("+++ Inside BooleanLiteral");
+    			backend.emitLW(T6, FP, 0, "Inside BooleanLiteral");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(ClassDef node) {
+    			System.out.println("+++ Inside ClassDef");
+    			backend.emitLW(T6, FP, 0, "Inside ClassDef");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(ClassType node) {
+    			System.out.println("+++ Inside ClassType");
+    			backend.emitLW(T6, FP, 0, "Inside ClassType");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(CompilerError node) {
+    			System.out.println("+++ Inside CompilerError");
+    			backend.emitLW(T6, FP, 0, "Inside CompilerError");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(Errors node) {
+    			System.out.println("+++ Inside Errors");
+    			backend.emitLW(T6, FP, 0, "Inside Errors");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(ExprStmt node) {
+    			System.out.println("+++ Inside ExprStmt");
+    			backend.emitLW(T6, FP, 0, "Inside ExprStmt: " + node.expr.kind);
+    			node.expr.dispatch(this);
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(ForStmt node) {
+    			System.out.println("+++ Inside ForStmt");
+    			backend.emitLW(T6, FP, 0, "Inside ForStmt");
+            return defaultAction(node);
+        }
+
+
+
+        @Override
+        public Void analyze(Identifier node) {
+    			System.out.println("+++ Inside Identifier");
+//    			List<String> params = funcInfo.getParams();
+//    			int i = 0;
+//    			for (i = 0; i < params.size(); i++) {
+//    				if (params.get(i).equals(node.name)) break;
+//    			}
+//    			backend.emitLW(A0, SP, ((i+1)-params.size())*4, "Load param " + (i+1) + " from left");
+    			backend.emitLW(T6, FP, 0, "Inside Identifier: " + node.name);
+            return null;
+        }
+
+        @Override
+        public Void analyze(IfExpr node) {
+    			System.out.println("+++ Inside IfExpr");
+    			backend.emitLW(T6, FP, 0, "Inside IfExpr");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(IfStmt node) {
+    			System.out.println("+++ Inside IfStmt");
+    			backend.emitLW(T6, FP, 0, "Inside IfStmt");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(IndexExpr node) {
+    			System.out.println("+++ Inside IndexExpr");
+    			backend.emitLW(T6, FP, 0, "Inside IndexExpr");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(IntegerLiteral node) {
+    			System.out.println("+++ Inside IntegerLiteral");
+    			backend.emitLA(A0, new Label("$int$prototype"), "Load prototype");
+    			backend.emitJAL(new Label("ra, alloc"), "");
+    			backend.emitLI(T0, node.value, "Load integer " + node.value);
+    			backend.emitSW(T0, A0, "@.__int__", null);
+    			backend.emitLW(T6, FP, 0, "Inside IntegerLiteral");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(ListExpr node) {
+    			System.out.println("+++ Inside ListExpr");
+    			backend.emitLW(T6, FP, 0, "Inside ListExpr");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(ListType node) {
+    			System.out.println("+++ Inside ListType");
+    			backend.emitLW(T6, FP, 0, "Inside ListType");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(MemberExpr node) {
+    			System.out.println("+++ Inside MemberExpr");
+    			backend.emitLW(T6, FP, 0, "Inside MemberExpr");
+            return defaultAction(node);
+        }
+
+
+
+        @Override
+        public Void analyze(NoneLiteral node) {
+    			System.out.println("+++ Inside NoneLiteral");
+    			backend.emitLW(T6, FP, 0, "Inside NoneLiteral");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(Program node) {
+    			System.out.println("+++ Inside Program");
+    			backend.emitLW(T6, FP, 0, "Inside Program");
+            return defaultAction(node);
+        }
+
+
+        @Override
+        public Void analyze(StringLiteral node) {
+    			System.out.println("+++ Inside StringLiteral");
+    			backend.emitLW(T6, FP, 0, "Inside StringLiteral");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(TypedVar node) {
+    			System.out.println("+++ Inside TypedVar");
+    			backend.emitLW(T6, FP, 0, "Inside TypedVar");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(UnaryExpr node) {
+    			System.out.println("+++ Inside UnaryExpr");
+    			backend.emitLW(T6, FP, 0, "Inside UnaryExpr");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(VarDef node) {
+    			System.out.println("+++ Inside VarDef");
+    			backend.emitLW(T6, FP, 0, "Inside VarDef");
+            return defaultAction(node);
+        }
+
+        @Override
+        public Void analyze(WhileStmt node) {
+    			System.out.println("+++ Inside WhileStmt");
+    			backend.emitLW(T6, FP, 0, "Inside WhileStmt");
+            return defaultAction(node);
+        }
+        
+        
+        
+        
+        
+        
+        // extras end here
         
     }