Value *VariableExprAST::Codegen() {
// Look this variable up in the function.
Value *V = NamedValues[Name];
- if (V == 0) return ErrorV("Unknown variable name");
+ if (!V)
+ return ErrorV("Unknown variable name");
// Load the value.
return Builder.CreateLoad(V, Name.c_str());
// Emit the start code first, without 'variable' in scope.
Value *StartVal = Start->Codegen();
- if (StartVal == 0) return 0;
+ if (!StartVal)
+ return nullptr;
// Store the value into the alloca.
Builder.CreateStore(StartVal, Alloca);
// Compute the end condition.
Value *EndCond = End->Codegen();
- if (EndCond == 0) return EndCond;
+ if (!EndCond)
+ return nullptr;
// Reload, increment, and restore the alloca. This handles the case where
// the body of the loop mutates the variable.
// Codegen the RHS.
Value *Val = RHS->Codegen();
- if (Val == 0) return 0;
+ if (!Val)
+ return nullptr;
// Look up the name.
Value *Variable = NamedValues[LHSE->getName()];
- if (Variable == 0) return ErrorV("Unknown variable name");
+ if (!Variable)
+ return ErrorV("Unknown variable name");
Builder.CreateStore(Val, Variable);
return Val;
...
static int gettok() {
...
- if (IdentifierStr == "in") return tok_in;
- if (IdentifierStr == "binary") return tok_binary;
- if (IdentifierStr == "unary") return tok_unary;
- if (IdentifierStr == "var") return tok_var;
+ if (IdentifierStr == "in")
+ return tok_in;
+ if (IdentifierStr == "binary")
+ return tok_binary;
+ if (IdentifierStr == "unary")
+ return tok_unary;
+ if (IdentifierStr == "var")
+ return tok_var;
return tok_identifier;
...
class VarExprAST : public ExprAST {
std::vector<std::pair<std::string, std::unique_ptr<ExprAST>>> VarNames;
std::unique_ptr<ExprAST> Body;
+
public:
VarExprAST(std::vector<std::pair<std::string, std::unique_ptr<ExprAST>>> VarNames,
std::unique_ptr<ExprAST> body)
/// ::= varexpr
static std::unique_ptr<ExprAST> ParsePrimary() {
switch (CurTok) {
- default: return Error("unknown token when expecting an expression");
- case tok_identifier: return ParseIdentifierExpr();
- case tok_number: return ParseNumberExpr();
- case '(': return ParseParenExpr();
- case tok_if: return ParseIfExpr();
- case tok_for: return ParseForExpr();
- case tok_var: return ParseVarExpr();
+ default:
+ return Error("unknown token when expecting an expression");
+ case tok_identifier:
+ return ParseIdentifierExpr();
+ case tok_number:
+ return ParseNumberExpr();
+ case '(':
+ return ParseParenExpr();
+ case tok_if:
+ return ParseIfExpr();
+ case tok_for:
+ return ParseForExpr();
+ case tok_var:
+ return ParseVarExpr();
}
}
getNextToken(); // eat 'in'.
auto Body = ParseExpression();
- if (!Body) return nullptr;
+ if (!Body)
+ return nullptr;
return llvm::make_unique<VarExprAST>(std::move(VarNames),
std::move(Body));
Value *InitVal;
if (Init) {
InitVal = Init->Codegen();
- if (InitVal == 0) return 0;
+ if (!InitVal)
+ return nullptr;
} else { // If not specified, use 0.0.
InitVal = ConstantFP::get(getGlobalContext(), APFloat(0.0));
}
// Codegen the body, now that all vars are in scope.
Value *BodyVal = Body->Codegen();
- if (BodyVal == 0) return 0;
+ if (!BodyVal)
+ return nullptr;
Finally, before returning, we restore the previous variable bindings: