Fix local binding and sequence compilation. (#41)

BowenFu · web-flow · commit 0c6953c19070 · 2022-01-01T21:20:56.000+08:00
* clean up.

* Fix local var.

* fix seq.

Co-authored-by: Bowen Fu &lt;missing&gt;
diff --git a/core.lisp b/core.lisp
@@ -237,5 +237,3 @@
 )
 
 (define (even num) (= (% num 2) 0)) 
-
-(define (my-cons car cdr) (lambda (dispatch) (if (= dispatch 'my-car) car cdr)))
diff --git a/include/lisp/compiler.h b/include/lisp/compiler.h
@@ -82,6 +82,10 @@ class SymbolTable
     {
         return mOrigFreeVars;
     }
+    auto nbDefinitions() const
+    {
+        return mNbDefinitions;
+    }
 };
 
 class Compiler
diff --git a/src/compiler.cpp b/src/compiler.cpp
@@ -150,9 +150,8 @@ void Compiler::compile(ExprPtr const& expr)
         for (auto const& e : seqPtr->mActions)
         {
             compile(e);
-            instructions().push_back(kPOP);
+            // todo, some actions push stack, some do not. Those pushing stack should pop their values.
         }
-        instructions().resize(instructions().size() - 1);
         return;
     }
     if (auto lambdaPtr = dynamic_cast<LambdaBase<CompoundProcedure> const*>(exprPtr))
@@ -174,13 +173,14 @@ void Compiler::compile(ExprPtr const& expr)
         instructions().push_back(kRET);
         auto funcInstructions = std::get<0>(mFuncStack.top());
         auto const freeVars = symbolTable().freeVariables();
+        auto const nbLocals = symbolTable().nbDefinitions() - args.size();
         mFuncStack.pop();
         for (auto f : freeVars)
         {
             emitVar(f);
         }
         auto const index = mCode.constantPool.size();
-        auto const funcSym = FunctionSymbol{lambdaPtr->mName, args.size(), variadic, /* nbLocals= */ 0, funcInstructions};
+        auto const funcSym = FunctionSymbol{lambdaPtr->mName, args.size(), variadic, nbLocals, funcInstructions};
         mCode.constantPool.push_back(funcSym);
         instructions().push_back(kCLOSURE);
         emitIndex(index);
diff --git a/test/lisp/testCompiler.cpp b/test/lisp/testCompiler.cpp
@@ -312,7 +312,7 @@ TEST(Compiler, rest)
     EXPECT_EQ(output, "(2 . (3 . nil))\n");
 }
 
-TEST(Compiler, localBinding)
+TEST(Compiler, freeVars)
 {
     std::string const source = " (define (my-cons car cdr) (lambda (dispatch) (if (= dispatch 'my-car) car cdr))) ((my-cons 1 2) 'my-cdr)";
     auto code = sourceToBytecode(source);
@@ -323,3 +323,15 @@ TEST(Compiler, localBinding)
     std::string output = testing::internal::GetCapturedStdout();
     EXPECT_EQ(output, "2\n");
 }
+
+TEST(Compiler, localBinding)
+{
+    std::string const source = " (define (my-cons car cdr) (define x car) (define y cdr) (lambda (dispatch) (if (= dispatch 'my-car) x y))) ((my-cons 1 2) 'my-car)";
+    auto code = sourceToBytecode(source);
+    code.instructions.push_back(kPRINT);
+    VM vm{code};
+    testing::internal::CaptureStdout();
+    vm.run();
+    std::string output = testing::internal::GetCapturedStdout();
+    EXPECT_EQ(output, "1\n");
+}

Original file line number	Diff line number	Diff line change
`@@ -237,5 +237,3 @@`
`237`	`237`	`)`
`238`	`238`
`239`	`239`	`(define (even num) (= (% num 2) 0))`
`240`		`-`
`241`		`-(define (my-cons car cdr) (lambda (dispatch) (if (= dispatch 'my-car) car cdr)))`
Original file line number	Diff line number	Diff line change
`@@ -82,6 +82,10 @@ class SymbolTable`
`82`	`82`	`{`
`83`	`83`	`return mOrigFreeVars;`
`84`	`84`	`}`
	`85`	`+ auto nbDefinitions() const`
	`86`	`+ {`
	`87`	`+ return mNbDefinitions;`
	`88`	`+ }`
`85`	`89`	`};`
`86`	`90`
`87`	`91`	`class Compiler`
Original file line number	Diff line number	Diff line change
`@@ -150,9 +150,8 @@ void Compiler::compile(ExprPtr const& expr)`
`150`	`150`	`for (auto const& e : seqPtr->mActions)`
`151`	`151`	`{`
`152`	`152`	`compile(e);`
`153`		`- instructions().push_back(kPOP);`
	`153`	`+ // todo, some actions push stack, some do not. Those pushing stack should pop their values.`
`154`	`154`	`}`
`155`		`- instructions().resize(instructions().size() - 1);`
`156`	`155`	`return;`
`157`	`156`	`}`
`158`	`157`	`if (auto lambdaPtr = dynamic_cast<LambdaBase<CompoundProcedure> const*>(exprPtr))`
`@@ -174,13 +173,14 @@ void Compiler::compile(ExprPtr const& expr)`
`174`	`173`	`instructions().push_back(kRET);`
`175`	`174`	`auto funcInstructions = std::get<0>(mFuncStack.top());`
`176`	`175`	`auto const freeVars = symbolTable().freeVariables();`
	`176`	`+ auto const nbLocals = symbolTable().nbDefinitions() - args.size();`
`177`	`177`	`mFuncStack.pop();`
`178`	`178`	`for (auto f : freeVars)`
`179`	`179`	`{`
`180`	`180`	`emitVar(f);`
`181`	`181`	`}`
`182`	`182`	`auto const index = mCode.constantPool.size();`
`183`		`- auto const funcSym = FunctionSymbol{lambdaPtr->mName, args.size(), variadic, /* nbLocals= */ 0, funcInstructions};`
	`183`	`+ auto const funcSym = FunctionSymbol{lambdaPtr->mName, args.size(), variadic, nbLocals, funcInstructions};`
`184`	`184`	`mCode.constantPool.push_back(funcSym);`
`185`	`185`	`instructions().push_back(kCLOSURE);`
`186`	`186`	`emitIndex(index);`