BUG FIX: nested implementation bug, id_local bug

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

@@ -221,6 +221,7 @@ public class CodeGenImpl extends CodeGenBase {
         }
 
         betterBackend.emitFunctionBegin(funcInfo.getFuncName(), null);
+        stmtAnalyzer.pushLocalVars(funcInfo.getLocals()); // regMgr should NEVER be used, because of this statement.
 
         // Emit code for function stmts
         for (Stmt stmt : funcInfo.getStatements()) {
@@ -277,20 +278,26 @@ public class CodeGenImpl extends CodeGenBase {
 
         // Extend StackVarInfo to add more info.
         private Map<String, Integer> localMap = new HashMap<>(); // Map from StackVarInfo to offset of FP.
-        public void initArgsMap(List<String> args) {
+        private void initArgsMap(List<String> args) {
             for(int i = 0; i < args.size(); ++i) {
                 int offset = (args.size() - i - 1) * backend.getWordSize();
                 localMap.put(args.get(i), offset);
             }
         }
-        public void initLocalVars(List<StackVarInfo> locals, int firstLocalOffset) {
+        private void initLocalVars(List<StackVarInfo> locals, int firstLocalOffset) {
+            for(int i = 0; i < locals.size(); ++i) {
+                StackVarInfo theLocal = locals.get(i);
+                int offset = firstLocalOffset - i * backend.getWordSize();
+                localMap.put(theLocal.getVarName(), offset);
+            }
+        }
+        public void pushLocalVars(List<StackVarInfo> locals) {
+            // This function generates some asm code, so it should only be called at RIGHT time.
             for(int i = 0; i < locals.size(); ++i) {
                 StackVarInfo theLocal = locals.get(i);
                 theLocal.getInitialValue().dispatch(this);
                 // The literal initial value is pushed to stack. That's the local!
                 // No need to push it again.
-                int offset = firstLocalOffset - i * backend.getWordSize();
-                localMap.put(theLocal.getVarName(), offset);
             }
         }
         private void emitLoadNestedParentVar(StackVarInfo varInfo, RiscVBackend.Register tmpReg, RiscVBackend.Register valReg_to_assign) {
@@ -310,10 +317,10 @@ public class CodeGenImpl extends CodeGenBase {
                 ++counter;
             }
             assert curr != null;
-            assert counter == curr.getDepth() - hisOwner.getDepth();
+            assert counter == funcInfo.getDepth() - hisOwner.getDepth();
             //! assert end
 
-            int depthDiff = curr.getDepth() - hisOwner.getDepth();
+            int depthDiff = funcInfo.getDepth() - hisOwner.getDepth();
             // If depthDiff is 0, then the variable is in current frame.
             backend.emitMV(tmpReg, FP, "LOAD NESTED VAR: Load current FP.");
             for(int i = 0; i < depthDiff; ++i) {
@@ -339,9 +346,10 @@ public class CodeGenImpl extends CodeGenBase {
             } else {
                 sym = funcInfo.getSymbolTable();
             }
-            epilogue = generateLocalLabel();
 
             if(funcInfo != null) {
+                // The init function below won't generate any asm code, so the stmtAnalyzer can be constructed at any time.
+                // because the constructor doesn't generate code! It won't affect anything.
                 initArgsMap(funcInfo.getParams());
                 initLocalVars(funcInfo.getLocals(), -3 * backend.getWordSize());
                 mapFuncInfoToStmtAnalyzer.put(funcInfo, this);