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587 lines
25 KiB
587 lines
25 KiB
package chocopy.pa3;
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import static chocopy.common.codegen.RiscVBackend.Register.A0;
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import static chocopy.common.codegen.RiscVBackend.Register.A1;
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import static chocopy.common.codegen.RiscVBackend.Register.FP;
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import static chocopy.common.codegen.RiscVBackend.Register.RA;
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import static chocopy.common.codegen.RiscVBackend.Register.SP;
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import static chocopy.common.codegen.RiscVBackend.Register.ZERO;
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import java.util.HashMap;
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import java.util.List;
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import java.util.Map;
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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.*;
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import chocopy.common.analysis.types.*;
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import chocopy.common.codegen.*;
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import java.util.HashMap;
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import java.util.List;
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import java.util.Map;
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import 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>
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* A large part of the functionality has already been implemented in the base
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* class, CodeGenBase. Make sure to read through that class, since you will want
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* to use many of its fields and utility methods in this class when emitting
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* code.
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*
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* <p>
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* Also read the PDF spec for details on what the base class does and what APIs
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* it exposes for its sub-class (this one). Of particular importance is knowing
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* what all the SymbolInfo classes contain.
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*/
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public class CodeGenImpl extends CodeGenBase
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{
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/** A code generator emitting instructions to BACKEND. */
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public CodeGenImpl(RiscVBackend backend)
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{
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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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/** Not implemented. */
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private final Label errorNI = new Label("error.NI");
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/**
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* Emits the top level of the program.
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*
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* <p>
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* This method is invoked exactly once, and is surrounded by some boilerplate
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* code that: (1) initializes the heap before the top-level begins and (2) exits
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* after the top-level ends.
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*
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* <p>
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* 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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{
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StmtAnalyzer stmtAnalyzer = new StmtAnalyzer(null);
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backend.emitADDI(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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{
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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>
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* This method is invoked once per function and method definition. At the code
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* generation stage, nested functions are emitted as separate functions of their
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* own. So if function `bar` is nested within function `foo`, you only emit
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* `foo`'s code for `foo` and only emit `bar`'s code for `bar`.
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*/
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protected void emitUserDefinedFunction(FuncInfo funcInfo)
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{
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backend.emitGlobalLabel(funcInfo.getCodeLabel());
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StmtAnalyzer stmtAnalyzer = new StmtAnalyzer(funcInfo);
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for (Stmt stmt : funcInfo.getStatements())
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{
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stmt.dispatch(stmtAnalyzer);
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}
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backend.emitMV(A0, ZERO, "Returning None implicitly");
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backend.emitLocalLabel(stmtAnalyzer.epilogue, "Epilogue");
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// FIXME: {... reset fp etc. ...}
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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<Register> {
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/*
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* The symbol table has all the info you need to determine what a given
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* identifier 'x' in the current scope is. You can use it as follows: SymbolInfo
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* x = sym.get("x");
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*
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* A SymbolInfo can be one the following: - ClassInfo: a descriptor for classes
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* - FuncInfo: a descriptor for functions/methods - AttrInfo: a descriptor for
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* attributes - GlobalVarInfo: a descriptor for global variables - StackVarInfo:
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* a descriptor for variables allocated on the stack, such as locals and
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* parameters
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*
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* Since the input program is assumed to be semantically valid and well-typed at
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* this stage, you can always assume that the symbol table contains valid
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* information. For example, in an expression `foo()` you KNOW that
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* sym.get("foo") will either be a FuncInfo or ClassInfo, but not any of the
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* other infos and never null.
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*
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* The symbol table in funcInfo has already been populated in the base class:
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* CodeGenBase. You do not need to add anything to the symbol table. Simply
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* query it with an identifier name to get a descriptor for a function, class,
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* variable, etc.
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*
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* The symbol table also maps nonlocal and global vars, so you only need to
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* lookup one symbol table and it will fetch the appropriate info for the var
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* 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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/** Label of code that exits from block. */
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protected Label elseBlock;
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/** Variable to keep track of offsets of stored variables */
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private Map<SymbolInfo, Integer> offsetMap = new HashMap<>();
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private final String size_label;
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/** Variable to store offset from frame pointer to identify next
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* empty space on stack frame to store variable*/
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private int sp_off;
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/** Variable to store maximum possible offset depending on stack size.*/
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private int max_sp;
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/**
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* An analyzer for the function described by FUNCINFO0, which is null for the
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* top level.
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*/
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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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sp_off = max_sp = 2;
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size_label = "@..main.size";
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} else {
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sym = funcInfo.getSymbolTable();
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sp_off = max_sp = funcInfo0.getLocals().size() + 2;
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size_label = "@"+funcInfo0.getFuncName()+".size";
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}
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epilogue = generateLocalLabel();
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}
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private void incSp(int i){
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sp_off+=i+1;
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max_sp = max_sp >= sp_off?max_sp:sp_off;
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}
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public Register analyze(CallExpr node) {
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SymbolInfo Ty = globalSymbols.get(node.function.name);
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if(Ty instanceof ClassInfo){
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//object create
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ClassInfo cls = (ClassInfo) Ty;
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/**
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la a0, $DoublingVector$prototype # Load pointer to prototype of: DoublingVector
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jal alloc # Allocate new object in A0
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sw a0, -12(fp) # Push on stack slot 3
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sw a0, -16(fp) # Push argument 0 from last.
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addi sp, fp, -16 # Set SP to last argument.
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lw a1, 8(a0) # Load address of object's dispatch table
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lw a1, 0(a1) # Load address of method: DoublingVector.__init__
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jalr a1 # Invoke method: DoublingVector.__init__
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addi sp, fp, -@..main.size # Set SP to stack frame top.
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lw a0, -12(fp) # Pop stack slot 3
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*/
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backend.emitLA(A0, cls.getPrototypeLabel(),
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String.format("Load pointer to prototype of: %s", cls.getClassName()));
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backend.emitJAL(objectAllocLabel, "Allocate new object in A0");
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backend.emitSW(A0, FP, -sp_off*wordSize, String.format("Push on stack slot %d", sp_off));
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incSp(0);
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backend.emitSW(A0, FP, -sp_off*wordSize, "Push argument 0 from last.");
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backend.emitADDI(SP, FP, sp_off, "Set SP to last argument.");
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backend.emitLW(A1, A0, getDispatchTableOffset(), "Load address of object's dispatch table");
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backend.emitLW(A1, A1, getMethodOffset(cls, "__init__"), String.format("Load address of method: %s.__init__", cls.getClassName()));
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backend.emitJALR(A1, String.format("Invoke method: %s.__init", cls.getClassName()));
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backend.emitADDI(SP, FP, "-"+size_label, "Set SP to stack frame top.");
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-- sp_off;
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backend.emitLW(A0, FP, -sp_off*wordSize, String.format("Pop stack slot %d", sp_off));
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} else {
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//func call
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}
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return A0;
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}
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@Override
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public Register analyze(NoneLiteral node)
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{
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backend.emitMV(Register.A0, Register.ZERO, "Load none");
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return Register.A0;
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}
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@Override
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public Register analyze(StringLiteral node)
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{
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Label l = constants.getStrConstant(node.value);
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backend.emitLA(Register.A0, l, "Load string literal");
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return Register.A0;
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}
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@Override
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public Register analyze(IntegerLiteral node)
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{
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backend.emitLI(Register.A0, node.value, "Load integer literal "+node.value);
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return Register.A0;
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}
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@Override
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public Register analyze(BooleanLiteral node)
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{
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if(node.value==true)
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backend.emitLI(Register.A0, 1, "Load boolean literal: true ");
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else
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backend.emitLI(Register.A0, 0, "Load boolean literal: false ");
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return Register.A0;
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}
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@Override
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public Register analyze(AssignStmt node)
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{
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Type t = node.value.getInferredType();
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if(t.isSpecialType() || t.isListType())
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{
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node.value.dispatch(this);
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if (sym.getParent() == null)
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{
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for(Expr target: node.targets)
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{
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GlobalVarInfo gvi=(GlobalVarInfo)sym.get(((Identifier)target).name);
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backend.emitSW(Register.A0, gvi.getLabel(), Register.T0, "Assign global: "+gvi.getVarName()+"(using tmp register)");
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}
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}
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else
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{
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for(Expr target: node.targets)
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{
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StackVarInfo svi = (StackVarInfo) sym.get(((Identifier)target).name);
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int loc = offsetMap.get(svi);
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backend.emitSW(Register.A0, Register.FP, -loc*4, "Load local variable: "+svi.getVarName());
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}
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}
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}
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else
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{//TODO: Object Assignment
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}
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return Register.A0;
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}
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@Override
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public Register analyze(ExprStmt node)
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{
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node.expr.dispatch(this);
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return null;
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}
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@Override
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public Register analyze(IfExpr node)
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{
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node.condition.dispatch(this);
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Label ln = generateLocalLabel();
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node.thenExpr.dispatch(this);
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backend.emitJ(ln, "Jump to end of if expression");
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backend.emitLocalLabel(elseBlock, "Else part of if expression");
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node.elseExpr.dispatch(this);
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backend.emitLocalLabel(ln, "End of if expression");
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return null;
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}
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@Override
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public Register analyze(IfStmt node)
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{
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node.condition.dispatch(this);
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Label ln = generateLocalLabel();
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for(Stmt s:node.thenBody)
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s.dispatch(this);
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backend.emitJ(ln, "Jump to end of if statement");
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backend.emitLocalLabel(elseBlock, "Else part of if statement");
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for(Stmt s:node.elseBody)
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s.dispatch(this);
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backend.emitLocalLabel(ln, "End of if statement");
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return null;
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}
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@Override
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public Register analyze(BinaryExpr node)
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{
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String operator = node.operator;
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if(node.left.getInferredType().equals(Type.INT_TYPE) && node.right.getInferredType().equals(Type.INT_TYPE))
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{
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node.left.dispatch(this);
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backend.emitSW(Register.A0, Register.FP, -sp_off*wordSize, "Push on stack slot "+sp_off);
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sp_off++;
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node.right.dispatch(this);
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sp_off--;
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backend.emitLW(Register.T0, Register.FP, -sp_off*wordSize, "Pop stack slot "+sp_off);
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// Arithmetic Operators
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if(operator.equals("+"))
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backend.emitADD(Register.A0, Register.A0, Register.T0, "Add operation");
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else if(operator.equals("-"))
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backend.emitSUB(Register.A0, Register.A0, Register.T0, "Sub operation");
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else if(operator.equals("*"))
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backend.emitMUL(Register.A0, Register.A0, Register.T0, "Mul operation");
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else if(operator.equals("//"))
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{
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Label label = generateLocalLabel();
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backend.emitBNEZ(Register.T0, label, "Check for Divide-by-zero");
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backend.emitJAL(errorDiv, "Divide-by-zero error");
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backend.emitLocalLabel(label, "Divide since divisor not zero");
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backend.emitDIV(Register.A0, Register.A0, Register.T0, "Divide operation");
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}
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else if(operator.equals("%"))
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{
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Label label = generateLocalLabel();
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backend.emitBNEZ(Register.T0, label, "Check for Divide-by-zero");
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backend.emitJAL(errorDiv, "Divide-by-zero error");
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backend.emitLocalLabel(label, "Divide since divisor not zero");
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backend.emitREM(Register.A0, Register.A0, Register.T0, "Modulus operation");
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}
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else
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{ // Comparison operators
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//elseBlock = generateLocalLabel();
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String comment="Operator: "+operator;
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if(operator.equals("=="))
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{
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backend.emitXOR(Register.A0, Register.A0, Register.T0, "Check for equality");
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backend.emitSEQZ(Register.A0, Register.A0, "Result is True if XOR equals 0");
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}
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else if(operator.equals("!="))
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{
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backend.emitXOR(Register.A0, Register.A0, Register.T0, "Check for inequality");
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backend.emitSNEZ(Register.A0, Register.A0, "Result is True if XOR does not equal 0");
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}
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else if(operator.equals("<"))
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backend.emitSLT(Register.A0,Register.A0, Register.T0, comment);
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else if(operator.equals(">"))
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backend.emitSLT(Register.A0, Register.T0, Register.A0, comment);
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else if(operator.equals("<="))
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{
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backend.emitADDI(Register.T0,Register.T0, 1, "Increment by 1");
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backend.emitSLT(Register.A0, Register.A0, Register.T0, comment);
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}
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else if(operator.equals(">="))
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{
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backend.emitADDI(Register.A0,Register.A0, 1, "Increment by 1");
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backend.emitSLT(Register.A0, Register.A0, Register.T0, comment);
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}
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else if(operator.equals("is"))
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{
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backend.emitXOR(Register.A0, Register.A0, Register.T0, "is operation");
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backend.emitSEQZ(Register.A0, Register.A0, "Result is True if XOR equals 0");
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}
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else
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{}
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}
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}
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else if(node.left.getInferredType().equals(Type.STR_TYPE) && node.right.getInferredType().equals(Type.STR_TYPE))
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{
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}
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return null;
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}
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@Override
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public Register analyze(UnaryExpr node)
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{
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if(node.operator.equals("-") && node.getInferredType().equals(Type.INT_TYPE))
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{
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node.operand.dispatch(this);
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backend.emitLI(Register.T0, -1, "Set value of Register T0 to -1");
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backend.emitMUL(Register.A0, Register.A0, Register.T0, "Multiply by -1");
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}
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else if(node.operator.equals("not") && node.getInferredType().equals(Type.BOOL_TYPE))
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{
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node.operand.dispatch(this);
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backend.emitSEQZ(Register.T0, Register.A0, "Not operation on Register A0");
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}
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else
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return null;
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return Register.A0;
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}
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@Override
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public Register analyze(Identifier node)
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{
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if (sym.getParent() == null)
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{
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GlobalVarInfo gvi=(GlobalVarInfo) sym.get(node.name);
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backend.emitLW(Register.A0, gvi.getLabel(), "Load global: "+gvi.getVarName());
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}
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else
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{
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StackVarInfo svi = (StackVarInfo) sym.get(node.name);
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int loc = offsetMap.get(svi);
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backend.emitLW(Register.A0, Register.FP, -loc*4, "Load local variable: "+svi.getVarName());
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}
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return null;
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}
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@Override
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public Register analyze(VarDef node)
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{
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StackVarInfo svi = (StackVarInfo) sym.get(node.var.identifier.name);
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node.value.dispatch(this);
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backend.emitSW(Register.A0, Register.FP, -sp_off*wordSize, "Store variable "+node.var.identifier.name+" value in Stack");
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offsetMap.put(svi, sp_off);
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sp_off++;
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return null;
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}
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@Override
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public Register analyze(WhileStmt node)
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{
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Label startLoop = generateLocalLabel();
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backend.emitLocalLabel(startLoop, "Beginning of while loop");
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node.condition.dispatch(this);
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Label endLoop = elseBlock;
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for(Stmt stmt:node.body)
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stmt.dispatch(this);
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backend.emitJ(startLoop, "Jump to beginning of loop");
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backend.emitLocalLabel(endLoop, "End of while loop");
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return null;
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}
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@Override
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public Register analyze(ListExpr node) {
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int l = node.elements.size();
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int i = l;
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for(Expr exp:node.elements)
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{
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Register r = exp.dispatch(this);
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backend.emitSW(r,Register.FP,-sp_off*wordSize,"Push argument "+i+" from last.");
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sp_off++;
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i--;
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}
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backend.emitLI(Register.A0, l, "Pass list length");
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backend.emitSW(Register.A0, Register.FP, -sp_off*wordSize, "Push argument "+i+" from last.");
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sp_off++;
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backend.emitADDI(Register.SP, Register.SP, -sp_off*wordSize, "Set SP to last argument.");
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//TODO: Store reference to variable
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return Register.A0;
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}
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@Override
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public Register analyze(ForStmt node) {
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System.out.println(node);
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/*
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|
node.
|
|
Label startLoop = generateLocalLabel();
|
|
backend.emitLocalLabel(startLoop, "Beginning of while loop");
|
|
node.condition.dispatch(this);
|
|
Label endLoop = elseBlock;
|
|
for(Stmt stmt:node.body)
|
|
stmt.dispatch(this);
|
|
backend.emitJ(startLoop, "Jump to beginning of loop");
|
|
backend.emitLocalLabel(endLoop, "End of while loop");*/
|
|
return null;
|
|
|
|
}
|
|
|
|
|
|
@Override
|
|
public Register analyze(IndexExpr node)
|
|
{
|
|
System.out.println(node);
|
|
return defaultAction(node);
|
|
}
|
|
|
|
|
|
public Register analyze(MemberExpr node)
|
|
{
|
|
ClassInfo objectClass = (ClassInfo) globalSymbols.get(node.object.getInferredType().className());
|
|
Label label = generateLocalLabel();
|
|
Register obj = node.object.dispatch(this);
|
|
|
|
backend.emitBNEZ(obj, label, "Ensure not None");
|
|
backend.emitJ(errorNone, "Go to error handler");
|
|
backend.emitLocalLabel(label, "Not None");
|
|
backend.emitLW(A0, obj, getAttrOffset(objectClass, node.member.name),
|
|
String.format("Get attribute: %s.%s", objectClass.getClassName(), node.member.name));
|
|
return A0;
|
|
}
|
|
|
|
public Register analyze(MethodCallExpr node)
|
|
{
|
|
Register obj = node.method.object.dispatch(this);
|
|
int n_args = node.args.size();
|
|
|
|
Label label = generateLocalLabel();
|
|
backend.emitBNEZ(obj, label, "Ensure not None");
|
|
backend.emitJ(errorNone, "Go to error handler");
|
|
backend.emitLocalLabel(label, "Not None");
|
|
incSp(n_args+1);
|
|
backend.emitSW(obj, FP, (n_args - sp_off) *wordSize, String.format("Push argument %d from last.", n_args));
|
|
|
|
for (int i = 0; i < n_args; ++i)
|
|
backend.emitSW(node.args.get(i).dispatch(this), FP, (n_args - i - 1 - sp_off) * wordSize,
|
|
String.format("Push argument %d from last.", n_args - i - 1));
|
|
|
|
backend.emitLW(A0, FP, (n_args- sp_off) * wordSize, String.format("Peek stack slot %d", sp_off - (n_args + 1)));
|
|
ClassInfo objectClass = (ClassInfo)sym.get(((Identifier)node.method.object).name);
|
|
|
|
backend.emitLW(A1, A0, getDispatchTableOffset(), "Load address of object's dispatch table");
|
|
backend.emitLW(A1, A1, getMethodOffset(objectClass, node.method.member.name),
|
|
String.format("Load address of method: %s.%s", objectClass.getClassName(), node.method.member.name));
|
|
backend.emitADDI(SP, FP, -sp_off * wordSize, "Set SP to last argument.");
|
|
backend.emitJALR(A1, String.format("Invoke method: %s.%s", objectClass.getClassName(), node.method.member.name));
|
|
backend.emitInsn(String.format("addi sp, fp, -%s", size_label), "Set SP to stack frame top.");
|
|
sp_off -= n_args+1;
|
|
|
|
return A0;
|
|
}
|
|
|
|
|
|
|
|
public Register analyze(ReturnStmt node)
|
|
{
|
|
return null;
|
|
}
|
|
|
|
}
|
|
|
|
/**
|
|
* 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");
|
|
emitErrorFunc(errorNI, "Not Implemented");
|
|
}
|
|
|
|
/** 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");
|
|
}
|
|
}
|