Fix sticky REPL value problem.

git-svn-id: http://svn.drobilla.net/resp/llvm-lisp@8 ad02d1e2-f140-0410-9f75-f8b11f17cedd

1 files changed, 22 insertions, 19 deletions

diff --git a/ll.cpp b/ll.cpp
index cc13b31..1633468 100644
--- a/ll.cpp
+++ b/ll.cpp
@@ -24,6 +24,7 @@
 #include <stack>
 #include <string>
 #include <vector>
+#include <sstream>
 #include "llvm/Analysis/Verifier.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/ExecutionEngine/ExecutionEngine.h"
@@ -174,13 +175,12 @@ struct ASTPrimitive : public ASTCall {
 
 /// Function prototype
 struct ASTPrototype : public AST {
-	ASTPrototype(bool foreign, const string& n, const vector<string>& p)
-			: _foreign(foreign), _name(n), _params(p) {}
+	ASTPrototype(const string& n, const vector<string>& p=vector<string>())
+			: _name(n), _params(p) {}
 	virtual bool evaluatable() const { return false; }
 	Value*       Codegen(CEnv& cenv) { return Funcgen(cenv); }
 	Function*    Funcgen(CEnv& cenv);
 private:
-	bool           _foreign;
 	string         _name;
 	vector<string> _params;
 };
@@ -222,7 +222,7 @@ parseSymbol(const SExp& exp)
 
 /// prototype ::= (name [arg*])
 static ASTPrototype*
-parsePrototype(bool foreign, const SExp& exp)
+parsePrototype(const SExp& exp)
 {
 	list<SExp>::const_iterator i = exp.list.begin();
 	const string& name = i->atom;
@@ -234,7 +234,7 @@ parsePrototype(bool foreign, const SExp& exp)
 		else
 			throw SyntaxError("Expected parameter name, found list");
 
-	return new ASTPrototype(foreign, name, args);
+	return new ASTPrototype(name, args);
 }
 
 /// callexpr ::= (expression [...])
@@ -248,7 +248,7 @@ parseCall(const SExp& exp)
 	const string& name = i->atom;
 	
 	if (name == "def" && (++i)->type == SExp::LIST) {
-		ASTPrototype* proto = parsePrototype(false, *i++);
+		ASTPrototype* proto = parsePrototype(*i++);
 		AST*          body  = parseExpression(*i++);
 		return new ASTFunction(proto, body);
 	}
@@ -268,7 +268,7 @@ parseCall(const SExp& exp)
 	} else if (name == "def") {
 		return new ASTDefinition(name, args);
 	} else if (name == "foreign") {
-		return parsePrototype(true, *++i++);
+		return parsePrototype(*++i++);
 	}
 
 	return new ASTCall(name, args);
@@ -296,7 +296,7 @@ parseExpression(const SExp& exp)
 /// Compile-time environment
 struct CEnv {
 	CEnv(Module* m, const TargetData* target)
-		: module(m), provider(module), fpm(&provider)
+		: module(m), provider(module), fpm(&provider), id(0)
 	{
 		// Set up the optimizer pipeline.
 		// Register info about how the target lays out data structures.
@@ -310,11 +310,15 @@ struct CEnv {
 		// Simplify control flow graph (delete unreachable blocks, etc).
 		fpm.add(createCFGSimplificationPass());
 	}
+	string gensym(const char* base="_") {
+		ostringstream s; s << base << id++; return s.str();
+	}
 	IRBuilder<>            builder;
 	Module*                module;
 	ExistingModuleProvider provider;
 	FunctionPassManager    fpm;
 	map<string, Value*>    env;
+	size_t                 id;
 };
 
 Value*
@@ -428,11 +432,10 @@ ASTPrototype::Funcgen(CEnv& cenv)
 			throw SyntaxError("Function redefined with mismatched arguments");
 	}
 
-	// Set names for all arguments and add to environment.
 	Function::arg_iterator a = f->arg_begin();
 	for (size_t i = 0; i != _params.size(); ++a, ++i) {
-		a->setName(_params[i]);
-		cenv.env[_params[i]] = a;
+		a->setName(_params[i]);   // Set name in generated code
+		cenv.env[_params[i]] = a; // Add to environment
 	}
 
 	return f;
@@ -467,14 +470,14 @@ ASTPrimitive::Codegen(CEnv& cenv)
 	Instruction::BinaryOps op;
 	assert(_name.length() == 1);
 	switch (_name[0]) {
-	case '+': op = Instruction::Add; break;
-	case '-': op = Instruction::Sub; break;
-	case '*': op = Instruction::Mul; break;
+	case '+': op = Instruction::Add;  break;
+	case '-': op = Instruction::Sub;  break;
+	case '*': op = Instruction::Mul;  break;
 	case '/': op = Instruction::FDiv; break;
 	case '%': op = Instruction::FRem; break;
-	case '&': op = Instruction::And; break;
-	case '|': op = Instruction::Or; break;
-	case '^': op = Instruction::Xor; break;
+	case '&': op = Instruction::And;  break;
+	case '|': op = Instruction::Or;   break;
+	case '^': op = Instruction::Xor;  break;
 	default: throw SyntaxError("Unknown primitive");
 	}
 	
@@ -516,13 +519,13 @@ repl(CEnv& cenv, ExecutionEngine* engine)
 			if (!ast)
 				continue;
 			if (ast->evaluatable()) {
-				ASTPrototype* proto = new ASTPrototype(false, "", vector<string>());
+				ASTPrototype* proto = new ASTPrototype(cenv.gensym("repl"));
 				ASTFunction*  func  = new ASTFunction(proto, ast);
 				Function*     code  = func->Funcgen(cenv);
 				void*         fp    = engine->getPointerToFunction(code);
 				double (*f)() = (double (*)())fp;
 				std::cout << f() << endl;
-				code->eraseFromParent();
+				//code->eraseFromParent();
 			} else {
 				Value* code = ast->Codegen(cenv); 
 				std::cout << "Generated code:" << endl;