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package chocopy.pa3;
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import chocopy.common.analysis.AbstractNodeAnalyzer;
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import chocopy.common.analysis.SymbolTable;
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import chocopy.common.astnodes.AssignStmt;
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import chocopy.common.astnodes.BinaryExpr;
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import chocopy.common.astnodes.BooleanLiteral;
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import chocopy.common.astnodes.CallExpr;
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import chocopy.common.astnodes.ClassDef;
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import chocopy.common.astnodes.ClassType;
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import chocopy.common.astnodes.CompilerError;
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import chocopy.common.astnodes.Errors;
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import chocopy.common.astnodes.Expr;
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import chocopy.common.astnodes.ExprStmt;
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import chocopy.common.astnodes.ForStmt;
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import chocopy.common.astnodes.FuncDef;
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import chocopy.common.astnodes.GlobalDecl;
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import chocopy.common.astnodes.Identifier;
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import chocopy.common.astnodes.IfExpr;
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import chocopy.common.astnodes.IfStmt;
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import chocopy.common.astnodes.IndexExpr;
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import chocopy.common.astnodes.IntegerLiteral;
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import chocopy.common.astnodes.ListExpr;
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import chocopy.common.astnodes.ListType;
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import chocopy.common.astnodes.MemberExpr;
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import chocopy.common.astnodes.MethodCallExpr;
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import chocopy.common.astnodes.NonLocalDecl;
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import chocopy.common.astnodes.NoneLiteral;
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import chocopy.common.astnodes.Program;
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import chocopy.common.astnodes.ReturnStmt;
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import chocopy.common.astnodes.Stmt;
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import chocopy.common.astnodes.StringLiteral;
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import chocopy.common.astnodes.TypedVar;
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import chocopy.common.astnodes.UnaryExpr;
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import chocopy.common.astnodes.VarDef;
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import chocopy.common.astnodes.WhileStmt;
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import chocopy.common.codegen.*;
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import java.util.List;
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import com.fasterxml.jackson.core.JsonProcessingException;
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import static chocopy.common.codegen.RiscVBackend.Register.*;
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/**
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* This is where the main implementation of PA3 will live.
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*
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* <p>A large part of the functionality has already been implemented in the base class, CodeGenBase.
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* Make sure to read through that class, since you will want to use many of its fields and utility
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* methods in this class when emitting code.
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*
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* <p>Also read the PDF spec for details on what the base class does and what APIs it exposes for
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* its sub-class (this one). Of particular importance is knowing what all the SymbolInfo classes
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* contain.
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*/
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public class CodeGenImpl extends CodeGenBase {
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/** A code generator emitting instructions to BACKEND. */
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public CodeGenImpl(RiscVBackend backend) {
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super(backend);
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}
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/** Operation on None. */
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private final Label errorNone = new Label("error.None");
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/** Division by zero. */
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private final Label errorDiv = new Label("error.Div");
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/** Index out of bounds. */
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private final Label errorOob = new Label("error.OOB");
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/**
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* Emits the top level of the program.
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*
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* <p>This method is invoked exactly once, and is surrounded by some boilerplate code that: (1)
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* initializes the heap before the top-level begins and (2) exits after the top-level ends.
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*
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* <p>You only need to generate code for statements.
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*
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* @param statements top level statements
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*/
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protected void emitTopLevel(List<Stmt> statements) {
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StmtAnalyzer stmtAnalyzer = new StmtAnalyzer(null);
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backend.emitADDI(
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SP, SP, -2 * backend.getWordSize(), "Saved FP and saved RA (unused at top level).");
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backend.emitSW(ZERO, SP, 0, "Top saved FP is 0.");
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backend.emitSW(ZERO, SP, 4, "Top saved RA is 0.");
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backend.emitADDI(FP, SP, 2 * backend.getWordSize(), "Set FP to previous SP.");
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for (Stmt stmt : statements) {
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stmt.dispatch(stmtAnalyzer);
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}
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backend.emitLI(A0, EXIT_ECALL, "Code for ecall: exit");
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backend.emitEcall(null);
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}
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/**
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* Emits the code for a function described by FUNCINFO.
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*
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* <p>This method is invoked once per function and method definition. At the code generation
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* stage, nested functions are emitted as separate functions of their own. So if function `bar`
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* is nested within function `foo`, you only emit `foo`'s code for `foo` and only emit `bar`'s
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* code for `bar`.
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*/
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protected void emitUserDefinedFunction(FuncInfo funcInfo) {
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backend.emitGlobalLabel(funcInfo.getCodeLabel());
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// --- Prologue ---
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// space for return address = 4
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// space for control link = 4
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// space for static link = 4
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// space for params = num of params * 4
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// space for locals = num of locals * 4
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int requiredStackSpace = 4 + 4 + 4 + funcInfo.getParams().size() * 4 + funcInfo.getLocals().size() * 4;
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backend.emitADDI(SP, SP, -requiredStackSpace, "Reserve space for stack frame.");
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backend.emitSW(RA, SP, requiredStackSpace-4, "return address");
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backend.emitSW(FP, SP, requiredStackSpace-8, "control link");
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// if we want to add static link
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//backend.emitSW(FP, SP, requiredStackSpace-12, "static link");
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backend.emitADDI(FP, SP, requiredStackSpace, "New fp is at old SP.");
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// --- Function Body ---
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// statements load all the variables that caller put on stack
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// statements use fp to load the variables
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// example: 0(fp) is the last variable (z) while 8(fp) is the first variable (x)
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// for function with 3 params f(x, y, z)
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StmtAnalyzer stmtAnalyzer = new StmtAnalyzer(funcInfo);
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for (Stmt stmt : funcInfo.getStatements()) {
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stmt.dispatch(stmtAnalyzer);
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}
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backend.emitJ(stmtAnalyzer.epilogue, "Jump to function epilogue");
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// --- Epilogue ---
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backend.emitLocalLabel(stmtAnalyzer.epilogue, "Epilogue");
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backend.emitLW(RA, FP, -4, "Get return address");
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backend.emitLW(FP, FP, -8, "Use control link to restore caller's fp");
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backend.emitADDI(SP, SP, requiredStackSpace, "Restore stack pointer");
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backend.emitJR(RA, "Return to caller");
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}
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/** An analyzer that encapsulates code generation for statements. */
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private class StmtAnalyzer extends AbstractNodeAnalyzer<Void> {
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/*
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* The symbol table has all the info you need to determine
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* what a given identifier 'x' in the current scope is. You can
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* use it as follows:
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* SymbolInfo x = sym.get("x");
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*
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* A SymbolInfo can be one the following:
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* - ClassInfo: a descriptor for classes
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* - FuncInfo: a descriptor for functions/methods
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* - AttrInfo: a descriptor for attributes
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* - GlobalVarInfo: a descriptor for global variables
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* - StackVarInfo: a descriptor for variables allocated on the stack,
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* such as locals and parameters
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*
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* Since the input program is assumed to be semantically
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* valid and well-typed at this stage, you can always assume that
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* the symbol table contains valid information. For example, in
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* an expression `foo()` you KNOW that sym.get("foo") will either be
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* a FuncInfo or ClassInfo, but not any of the other infos
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* and never null.
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*
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* The symbol table in funcInfo has already been populated in
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* the base class: CodeGenBase. You do not need to add anything to
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* the symbol table. Simply query it with an identifier name to
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* get a descriptor for a function, class, variable, etc.
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*
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* The symbol table also maps nonlocal and global vars, so you
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* only need to lookup one symbol table and it will fetch the
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* appropriate info for the var that is currently in scope.
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*/
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/** Symbol table for my statements. */
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private final SymbolTable<SymbolInfo> sym;
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/** Label of code that exits from procedure. */
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protected final Label epilogue;
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/** The descriptor for the current function, or null at the top level. */
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private final FuncInfo funcInfo;
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/** An analyzer for the function described by FUNCINFO0, which is null for the top level. */
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StmtAnalyzer(FuncInfo funcInfo0) {
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funcInfo = funcInfo0;
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if (funcInfo == null) {
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sym = globalSymbols;
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} else {
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sym = funcInfo.getSymbolTable();
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}
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epilogue = generateLocalLabel();
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}
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@Override
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public Void analyze(ReturnStmt stmt) {
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System.out.println("*** ReturnStmt");
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backend.emitLW(T6, FP, 0, "Inside ReturnStmt");
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// Expr expr = stmt.value;
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// // All expressions should save their end result in A0
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// expr.dispatch(this);
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backend.emitLW(A0, FP, 0, "Load var: " + "last");
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return null;
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}
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@Override
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public Void analyze(CallExpr node) {
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System.out.println("*** CallExpr");
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backend.emitLW(T6, FP, 0, "Inside CallExpr: " + node.function.name);
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// function
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Identifier functionId = node.function;
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List<Expr> args = node.args;
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int spaceRequiredForArgs = (args.size() + 1)*4;
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//backend.emitSW(A0, SP, -4, "Put static link");
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for (int i = 0; i < args.size(); i++) {
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int argNum = i + 1;
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int slotNum = argNum + 1; // We have extra slot for static link
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Expr expr = args.get(i);
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expr.dispatch(this);
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// All expressions should save their end result in A0
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// So, once expr is evaluated add value inside A0 onto stack as an argument
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backend.emitSW(A0, SP, -4*slotNum, "Push argument " + argNum + " from left");
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}
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backend.emitADDI(SP, SP, -spaceRequiredForArgs, "Set SP to last argument.");
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backend.emitJAL(new Label("$"+functionId.name), "Invoke function: " + functionId.name);
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backend.emitADDI(SP, SP, spaceRequiredForArgs, "Set SP to stack frame top.");
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return null;
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}
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@Override
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public Void analyze(MethodCallExpr node) {
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System.out.println("*** MethodCallExpr");
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backend.emitLW(T6, FP, 0, "Inside MethodCallExpr");
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// function
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return defaultAction(node);
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}
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@Override
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public Void analyze(FuncDef node) {
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System.out.println("*** FuncDef");
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backend.emitLW(T6, FP, 0, "Inside FuncDef");
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// function
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return defaultAction(node);
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}
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@Override
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public Void analyze(GlobalDecl node) {
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System.out.println("*** GlobalDecl");
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backend.emitLW(T6, FP, 0, "Inside GlobalDecl");
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// function
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return defaultAction(node);
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}
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@Override
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public Void analyze(NonLocalDecl node) {
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System.out.println("*** NonLocalDecl");
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backend.emitLW(T6, FP, 0, "Inside NonLocalDecl");
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// function
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return defaultAction(node);
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}
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// methods below are only for testing, remove or comment them when merging
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@Override
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public Void analyze(AssignStmt node) {
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System.out.println("+++ Inside AssignStmt");
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backend.emitLW(T6, FP, 0, "Inside AssignStmt");
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return defaultAction(node);
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}
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@Override
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public Void analyze(BinaryExpr node) {
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System.out.println("+++ Inside BinaryExpr");
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backend.emitLW(T6, FP, 0, "Inside BinaryExpr");
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return defaultAction(node);
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}
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@Override
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public Void analyze(BooleanLiteral node) {
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System.out.println("+++ Inside BooleanLiteral");
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backend.emitLW(T6, FP, 0, "Inside BooleanLiteral");
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return defaultAction(node);
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}
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@Override
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public Void analyze(ClassDef node) {
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System.out.println("+++ Inside ClassDef");
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backend.emitLW(T6, FP, 0, "Inside ClassDef");
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return defaultAction(node);
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}
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@Override
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public Void analyze(ClassType node) {
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System.out.println("+++ Inside ClassType");
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backend.emitLW(T6, FP, 0, "Inside ClassType");
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return defaultAction(node);
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}
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@Override
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public Void analyze(CompilerError node) {
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System.out.println("+++ Inside CompilerError");
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backend.emitLW(T6, FP, 0, "Inside CompilerError");
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return defaultAction(node);
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}
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@Override
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public Void analyze(Errors node) {
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System.out.println("+++ Inside Errors");
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backend.emitLW(T6, FP, 0, "Inside Errors");
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return defaultAction(node);
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}
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@Override
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public Void analyze(ExprStmt node) {
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System.out.println("+++ Inside ExprStmt");
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backend.emitLW(T6, FP, 0, "Inside ExprStmt: " + node.expr.kind);
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node.expr.dispatch(this);
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return defaultAction(node);
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}
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@Override
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public Void analyze(ForStmt node) {
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System.out.println("+++ Inside ForStmt");
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backend.emitLW(T6, FP, 0, "Inside ForStmt");
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return defaultAction(node);
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}
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@Override
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public Void analyze(Identifier node) {
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System.out.println("+++ Inside Identifier");
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// List<String> params = funcInfo.getParams();
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// int i = 0;
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// for (i = 0; i < params.size(); i++) {
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// if (params.get(i).equals(node.name)) break;
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// }
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// backend.emitLW(A0, SP, ((i+1)-params.size())*4, "Load param " + (i+1) + " from left");
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backend.emitLW(T6, FP, 0, "Inside Identifier: " + node.name);
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return null;
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}
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@Override
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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
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Emits custom code in the CODE segment.
|
|
|
|
*
|
|
|
|
* <p>This method is called after emitting the top level and the function bodies for each
|
|
|
|
* function.
|
|
|
|
*
|
|
|
|
* <p>You can use this method to emit anything you want outside of the top level or functions,
|
|
|
|
* e.g. custom routines that you may want to call from within your code to do common tasks. This
|
|
|
|
* is not strictly needed. You might not modify this at all and still complete the assignment.
|
|
|
|
*
|
|
|
|
* <p>To start you off, here is an implementation of three routines that will be commonly needed
|
|
|
|
* from within the code you will generate for statements.
|
|
|
|
*
|
|
|
|
* <p>The routines are error handlers for operations on None, index out of bounds, and division
|
|
|
|
* by zero. They never return to their caller. Just jump to one of these routines to throw an
|
|
|
|
* error and exit the program. For example, to throw an OOB error: backend.emitJ(errorOob, "Go
|
|
|
|
* to out-of-bounds error and abort");
|
|
|
|
*/
|
|
|
|
protected void emitCustomCode() {
|
|
|
|
emitErrorFunc(errorNone, "Operation on None");
|
|
|
|
emitErrorFunc(errorDiv, "Division by zero");
|
|
|
|
emitErrorFunc(errorOob, "Index out of bounds");
|
|
|
|
}
|
|
|
|
|
|
|
|
/** Emit an error routine labeled ERRLABEL that aborts with message MSG. */
|
|
|
|
private void emitErrorFunc(Label errLabel, String msg) {
|
|
|
|
backend.emitGlobalLabel(errLabel);
|
|
|
|
backend.emitLI(A0, ERROR_NONE, "Exit code for: " + msg);
|
|
|
|
backend.emitLA(A1, constants.getStrConstant(msg), "Load error message as str");
|
|
|
|
backend.emitADDI(
|
|
|
|
A1, A1, getAttrOffset(strClass, "__str__"), "Load address of attribute __str__");
|
|
|
|
backend.emitJ(abortLabel, "Abort");
|
|
|
|
}
|
|
|
|
}
|