1 #include "llvm/ADT/STLExtras.h"
2 #include "llvm/Analysis/Passes.h"
3 #include "llvm/ExecutionEngine/ExecutionEngine.h"
4 #include "llvm/ExecutionEngine/MCJIT.h"
5 #include "llvm/ExecutionEngine/SectionMemoryManager.h"
6 #include "llvm/IR/DataLayout.h"
7 #include "llvm/IR/DerivedTypes.h"
8 #include "llvm/IR/IRBuilder.h"
9 #include "llvm/IR/LLVMContext.h"
10 #include "llvm/IR/LegacyPassManager.h"
11 #include "llvm/IR/Module.h"
12 #include "llvm/IR/Verifier.h"
13 #include "llvm/Support/TargetSelect.h"
14 #include "llvm/Transforms/Scalar.h"
22 //===----------------------------------------------------------------------===//
24 //===----------------------------------------------------------------------===//
26 // The lexer returns tokens [0-255] if it is an unknown character, otherwise one
27 // of these for known things.
54 static std::string IdentifierStr; // Filled in if tok_identifier
55 static double NumVal; // Filled in if tok_number
57 /// gettok - Return the next token from standard input.
59 static int LastChar = ' ';
61 // Skip any whitespace.
62 while (isspace(LastChar))
65 if (isalpha(LastChar)) { // identifier: [a-zA-Z][a-zA-Z0-9]*
66 IdentifierStr = LastChar;
67 while (isalnum((LastChar = getchar())))
68 IdentifierStr += LastChar;
70 if (IdentifierStr == "def")
72 if (IdentifierStr == "extern")
74 if (IdentifierStr == "if")
76 if (IdentifierStr == "then")
78 if (IdentifierStr == "else")
80 if (IdentifierStr == "for")
82 if (IdentifierStr == "in")
84 if (IdentifierStr == "binary")
86 if (IdentifierStr == "unary")
88 if (IdentifierStr == "var")
90 return tok_identifier;
93 if (isdigit(LastChar) || LastChar == '.') { // Number: [0-9.]+
98 } while (isdigit(LastChar) || LastChar == '.');
100 NumVal = strtod(NumStr.c_str(), 0);
104 if (LastChar == '#') {
105 // Comment until end of line.
107 LastChar = getchar();
108 while (LastChar != EOF && LastChar != '\n' && LastChar != '\r');
114 // Check for end of file. Don't eat the EOF.
118 // Otherwise, just return the character as its ascii value.
119 int ThisChar = LastChar;
120 LastChar = getchar();
124 //===----------------------------------------------------------------------===//
125 // Abstract Syntax Tree (aka Parse Tree)
126 //===----------------------------------------------------------------------===//
128 /// ExprAST - Base class for all expression nodes.
131 virtual ~ExprAST() {}
132 virtual Value *Codegen() = 0;
135 /// NumberExprAST - Expression class for numeric literals like "1.0".
136 class NumberExprAST : public ExprAST {
140 NumberExprAST(double val) : Val(val) {}
141 Value *Codegen() override;
144 /// VariableExprAST - Expression class for referencing a variable, like "a".
145 class VariableExprAST : public ExprAST {
149 VariableExprAST(const std::string &name) : Name(name) {}
150 const std::string &getName() const { return Name; }
151 Value *Codegen() override;
154 /// UnaryExprAST - Expression class for a unary operator.
155 class UnaryExprAST : public ExprAST {
160 UnaryExprAST(char opcode, ExprAST *operand)
161 : Opcode(opcode), Operand(operand) {}
162 Value *Codegen() override;
165 /// BinaryExprAST - Expression class for a binary operator.
166 class BinaryExprAST : public ExprAST {
171 BinaryExprAST(char op, ExprAST *lhs, ExprAST *rhs)
172 : Op(op), LHS(lhs), RHS(rhs) {}
173 Value *Codegen() override;
176 /// CallExprAST - Expression class for function calls.
177 class CallExprAST : public ExprAST {
179 std::vector<ExprAST *> Args;
182 CallExprAST(const std::string &callee, std::vector<ExprAST *> &args)
183 : Callee(callee), Args(args) {}
184 Value *Codegen() override;
187 /// IfExprAST - Expression class for if/then/else.
188 class IfExprAST : public ExprAST {
189 ExprAST *Cond, *Then, *Else;
192 IfExprAST(ExprAST *cond, ExprAST *then, ExprAST *_else)
193 : Cond(cond), Then(then), Else(_else) {}
194 Value *Codegen() override;
197 /// ForExprAST - Expression class for for/in.
198 class ForExprAST : public ExprAST {
200 ExprAST *Start, *End, *Step, *Body;
203 ForExprAST(const std::string &varname, ExprAST *start, ExprAST *end,
204 ExprAST *step, ExprAST *body)
205 : VarName(varname), Start(start), End(end), Step(step), Body(body) {}
206 Value *Codegen() override;
209 /// VarExprAST - Expression class for var/in
210 class VarExprAST : public ExprAST {
211 std::vector<std::pair<std::string, ExprAST *> > VarNames;
215 VarExprAST(const std::vector<std::pair<std::string, ExprAST *> > &varnames,
217 : VarNames(varnames), Body(body) {}
219 Value *Codegen() override;
222 /// PrototypeAST - This class represents the "prototype" for a function,
223 /// which captures its argument names as well as if it is an operator.
226 std::vector<std::string> Args;
228 unsigned Precedence; // Precedence if a binary op.
230 PrototypeAST(const std::string &name, const std::vector<std::string> &args,
231 bool isoperator = false, unsigned prec = 0)
232 : Name(name), Args(args), isOperator(isoperator), Precedence(prec) {}
234 bool isUnaryOp() const { return isOperator && Args.size() == 1; }
235 bool isBinaryOp() const { return isOperator && Args.size() == 2; }
237 char getOperatorName() const {
238 assert(isUnaryOp() || isBinaryOp());
239 return Name[Name.size() - 1];
242 unsigned getBinaryPrecedence() const { return Precedence; }
246 void CreateArgumentAllocas(Function *F);
249 /// FunctionAST - This class represents a function definition itself.
255 FunctionAST(PrototypeAST *proto, ExprAST *body) : Proto(proto), Body(body) {}
259 } // end anonymous namespace
261 //===----------------------------------------------------------------------===//
263 //===----------------------------------------------------------------------===//
265 /// CurTok/getNextToken - Provide a simple token buffer. CurTok is the current
266 /// token the parser is looking at. getNextToken reads another token from the
267 /// lexer and updates CurTok with its results.
269 static int getNextToken() { return CurTok = gettok(); }
271 /// BinopPrecedence - This holds the precedence for each binary operator that is
273 static std::map<char, int> BinopPrecedence;
275 /// GetTokPrecedence - Get the precedence of the pending binary operator token.
276 static int GetTokPrecedence() {
277 if (!isascii(CurTok))
280 // Make sure it's a declared binop.
281 int TokPrec = BinopPrecedence[CurTok];
287 /// Error* - These are little helper functions for error handling.
288 ExprAST *Error(const char *Str) {
289 fprintf(stderr, "Error: %s\n", Str);
292 PrototypeAST *ErrorP(const char *Str) {
296 FunctionAST *ErrorF(const char *Str) {
301 static ExprAST *ParseExpression();
305 /// ::= identifier '(' expression* ')'
306 static ExprAST *ParseIdentifierExpr() {
307 std::string IdName = IdentifierStr;
309 getNextToken(); // eat identifier.
311 if (CurTok != '(') // Simple variable ref.
312 return new VariableExprAST(IdName);
315 getNextToken(); // eat (
316 std::vector<ExprAST *> Args;
319 ExprAST *Arg = ParseExpression();
328 return Error("Expected ')' or ',' in argument list");
336 return new CallExprAST(IdName, Args);
339 /// numberexpr ::= number
340 static ExprAST *ParseNumberExpr() {
341 ExprAST *Result = new NumberExprAST(NumVal);
342 getNextToken(); // consume the number
346 /// parenexpr ::= '(' expression ')'
347 static ExprAST *ParseParenExpr() {
348 getNextToken(); // eat (.
349 ExprAST *V = ParseExpression();
354 return Error("expected ')'");
355 getNextToken(); // eat ).
359 /// ifexpr ::= 'if' expression 'then' expression 'else' expression
360 static ExprAST *ParseIfExpr() {
361 getNextToken(); // eat the if.
364 ExprAST *Cond = ParseExpression();
368 if (CurTok != tok_then)
369 return Error("expected then");
370 getNextToken(); // eat the then
372 ExprAST *Then = ParseExpression();
376 if (CurTok != tok_else)
377 return Error("expected else");
381 ExprAST *Else = ParseExpression();
385 return new IfExprAST(Cond, Then, Else);
388 /// forexpr ::= 'for' identifier '=' expr ',' expr (',' expr)? 'in' expression
389 static ExprAST *ParseForExpr() {
390 getNextToken(); // eat the for.
392 if (CurTok != tok_identifier)
393 return Error("expected identifier after for");
395 std::string IdName = IdentifierStr;
396 getNextToken(); // eat identifier.
399 return Error("expected '=' after for");
400 getNextToken(); // eat '='.
402 ExprAST *Start = ParseExpression();
406 return Error("expected ',' after for start value");
409 ExprAST *End = ParseExpression();
413 // The step value is optional.
417 Step = ParseExpression();
422 if (CurTok != tok_in)
423 return Error("expected 'in' after for");
424 getNextToken(); // eat 'in'.
426 ExprAST *Body = ParseExpression();
430 return new ForExprAST(IdName, Start, End, Step, Body);
433 /// varexpr ::= 'var' identifier ('=' expression)?
434 // (',' identifier ('=' expression)?)* 'in' expression
435 static ExprAST *ParseVarExpr() {
436 getNextToken(); // eat the var.
438 std::vector<std::pair<std::string, ExprAST *> > VarNames;
440 // At least one variable name is required.
441 if (CurTok != tok_identifier)
442 return Error("expected identifier after var");
445 std::string Name = IdentifierStr;
446 getNextToken(); // eat identifier.
448 // Read the optional initializer.
451 getNextToken(); // eat the '='.
453 Init = ParseExpression();
458 VarNames.push_back(std::make_pair(Name, Init));
460 // End of var list, exit loop.
463 getNextToken(); // eat the ','.
465 if (CurTok != tok_identifier)
466 return Error("expected identifier list after var");
469 // At this point, we have to have 'in'.
470 if (CurTok != tok_in)
471 return Error("expected 'in' keyword after 'var'");
472 getNextToken(); // eat 'in'.
474 ExprAST *Body = ParseExpression();
478 return new VarExprAST(VarNames, Body);
482 /// ::= identifierexpr
488 static ExprAST *ParsePrimary() {
491 return Error("unknown token when expecting an expression");
493 return ParseIdentifierExpr();
495 return ParseNumberExpr();
497 return ParseParenExpr();
499 return ParseIfExpr();
501 return ParseForExpr();
503 return ParseVarExpr();
510 static ExprAST *ParseUnary() {
511 // If the current token is not an operator, it must be a primary expr.
512 if (!isascii(CurTok) || CurTok == '(' || CurTok == ',')
513 return ParsePrimary();
515 // If this is a unary operator, read it.
518 if (ExprAST *Operand = ParseUnary())
519 return new UnaryExprAST(Opc, Operand);
525 static ExprAST *ParseBinOpRHS(int ExprPrec, ExprAST *LHS) {
526 // If this is a binop, find its precedence.
528 int TokPrec = GetTokPrecedence();
530 // If this is a binop that binds at least as tightly as the current binop,
531 // consume it, otherwise we are done.
532 if (TokPrec < ExprPrec)
535 // Okay, we know this is a binop.
537 getNextToken(); // eat binop
539 // Parse the unary expression after the binary operator.
540 ExprAST *RHS = ParseUnary();
544 // If BinOp binds less tightly with RHS than the operator after RHS, let
545 // the pending operator take RHS as its LHS.
546 int NextPrec = GetTokPrecedence();
547 if (TokPrec < NextPrec) {
548 RHS = ParseBinOpRHS(TokPrec + 1, RHS);
554 LHS = new BinaryExprAST(BinOp, LHS, RHS);
559 /// ::= unary binoprhs
561 static ExprAST *ParseExpression() {
562 ExprAST *LHS = ParseUnary();
566 return ParseBinOpRHS(0, LHS);
570 /// ::= id '(' id* ')'
571 /// ::= binary LETTER number? (id, id)
572 /// ::= unary LETTER (id)
573 static PrototypeAST *ParsePrototype() {
576 unsigned Kind = 0; // 0 = identifier, 1 = unary, 2 = binary.
577 unsigned BinaryPrecedence = 30;
581 return ErrorP("Expected function name in prototype");
583 FnName = IdentifierStr;
589 if (!isascii(CurTok))
590 return ErrorP("Expected unary operator");
592 FnName += (char)CurTok;
598 if (!isascii(CurTok))
599 return ErrorP("Expected binary operator");
601 FnName += (char)CurTok;
605 // Read the precedence if present.
606 if (CurTok == tok_number) {
607 if (NumVal < 1 || NumVal > 100)
608 return ErrorP("Invalid precedecnce: must be 1..100");
609 BinaryPrecedence = (unsigned)NumVal;
616 return ErrorP("Expected '(' in prototype");
618 std::vector<std::string> ArgNames;
619 while (getNextToken() == tok_identifier)
620 ArgNames.push_back(IdentifierStr);
622 return ErrorP("Expected ')' in prototype");
625 getNextToken(); // eat ')'.
627 // Verify right number of names for operator.
628 if (Kind && ArgNames.size() != Kind)
629 return ErrorP("Invalid number of operands for operator");
631 return new PrototypeAST(FnName, ArgNames, Kind != 0, BinaryPrecedence);
634 /// definition ::= 'def' prototype expression
635 static FunctionAST *ParseDefinition() {
636 getNextToken(); // eat def.
637 PrototypeAST *Proto = ParsePrototype();
641 if (ExprAST *E = ParseExpression())
642 return new FunctionAST(Proto, E);
646 /// toplevelexpr ::= expression
647 static FunctionAST *ParseTopLevelExpr() {
648 if (ExprAST *E = ParseExpression()) {
649 // Make an anonymous proto.
650 PrototypeAST *Proto = new PrototypeAST("", std::vector<std::string>());
651 return new FunctionAST(Proto, E);
656 /// external ::= 'extern' prototype
657 static PrototypeAST *ParseExtern() {
658 getNextToken(); // eat extern.
659 return ParsePrototype();
662 //===----------------------------------------------------------------------===//
664 //===----------------------------------------------------------------------===//
666 static Module *TheModule;
667 static IRBuilder<> Builder(getGlobalContext());
668 static std::map<std::string, AllocaInst *> NamedValues;
669 static legacy::FunctionPassManager *TheFPM;
671 Value *ErrorV(const char *Str) {
676 /// CreateEntryBlockAlloca - Create an alloca instruction in the entry block of
677 /// the function. This is used for mutable variables etc.
678 static AllocaInst *CreateEntryBlockAlloca(Function *TheFunction,
679 const std::string &VarName) {
680 IRBuilder<> TmpB(&TheFunction->getEntryBlock(),
681 TheFunction->getEntryBlock().begin());
682 return TmpB.CreateAlloca(Type::getDoubleTy(getGlobalContext()), 0,
686 Value *NumberExprAST::Codegen() {
687 return ConstantFP::get(getGlobalContext(), APFloat(Val));
690 Value *VariableExprAST::Codegen() {
691 // Look this variable up in the function.
692 Value *V = NamedValues[Name];
694 return ErrorV("Unknown variable name");
697 return Builder.CreateLoad(V, Name.c_str());
700 Value *UnaryExprAST::Codegen() {
701 Value *OperandV = Operand->Codegen();
705 Function *F = TheModule->getFunction(std::string("unary") + Opcode);
707 return ErrorV("Unknown unary operator");
709 return Builder.CreateCall(F, OperandV, "unop");
712 Value *BinaryExprAST::Codegen() {
713 // Special case '=' because we don't want to emit the LHS as an expression.
715 // Assignment requires the LHS to be an identifier.
716 // This assume we're building without RTTI because LLVM builds that way by
717 // default. If you build LLVM with RTTI this can be changed to a
718 // dynamic_cast for automatic error checking.
719 VariableExprAST *LHSE = reinterpret_cast<VariableExprAST *>(LHS);
721 return ErrorV("destination of '=' must be a variable");
723 Value *Val = RHS->Codegen();
728 Value *Variable = NamedValues[LHSE->getName()];
730 return ErrorV("Unknown variable name");
732 Builder.CreateStore(Val, Variable);
736 Value *L = LHS->Codegen();
737 Value *R = RHS->Codegen();
738 if (L == 0 || R == 0)
743 return Builder.CreateFAdd(L, R, "addtmp");
745 return Builder.CreateFSub(L, R, "subtmp");
747 return Builder.CreateFMul(L, R, "multmp");
749 L = Builder.CreateFCmpULT(L, R, "cmptmp");
750 // Convert bool 0/1 to double 0.0 or 1.0
751 return Builder.CreateUIToFP(L, Type::getDoubleTy(getGlobalContext()),
757 // If it wasn't a builtin binary operator, it must be a user defined one. Emit
759 Function *F = TheModule->getFunction(std::string("binary") + Op);
760 assert(F && "binary operator not found!");
762 Value *Ops[] = { L, R };
763 return Builder.CreateCall(F, Ops, "binop");
766 Value *CallExprAST::Codegen() {
767 // Look up the name in the global module table.
768 Function *CalleeF = TheModule->getFunction(Callee);
770 return ErrorV("Unknown function referenced");
772 // If argument mismatch error.
773 if (CalleeF->arg_size() != Args.size())
774 return ErrorV("Incorrect # arguments passed");
776 std::vector<Value *> ArgsV;
777 for (unsigned i = 0, e = Args.size(); i != e; ++i) {
778 ArgsV.push_back(Args[i]->Codegen());
779 if (ArgsV.back() == 0)
783 return Builder.CreateCall(CalleeF, ArgsV, "calltmp");
786 Value *IfExprAST::Codegen() {
787 Value *CondV = Cond->Codegen();
791 // Convert condition to a bool by comparing equal to 0.0.
792 CondV = Builder.CreateFCmpONE(
793 CondV, ConstantFP::get(getGlobalContext(), APFloat(0.0)), "ifcond");
795 Function *TheFunction = Builder.GetInsertBlock()->getParent();
797 // Create blocks for the then and else cases. Insert the 'then' block at the
798 // end of the function.
800 BasicBlock::Create(getGlobalContext(), "then", TheFunction);
801 BasicBlock *ElseBB = BasicBlock::Create(getGlobalContext(), "else");
802 BasicBlock *MergeBB = BasicBlock::Create(getGlobalContext(), "ifcont");
804 Builder.CreateCondBr(CondV, ThenBB, ElseBB);
807 Builder.SetInsertPoint(ThenBB);
809 Value *ThenV = Then->Codegen();
813 Builder.CreateBr(MergeBB);
814 // Codegen of 'Then' can change the current block, update ThenBB for the PHI.
815 ThenBB = Builder.GetInsertBlock();
818 TheFunction->getBasicBlockList().push_back(ElseBB);
819 Builder.SetInsertPoint(ElseBB);
821 Value *ElseV = Else->Codegen();
825 Builder.CreateBr(MergeBB);
826 // Codegen of 'Else' can change the current block, update ElseBB for the PHI.
827 ElseBB = Builder.GetInsertBlock();
830 TheFunction->getBasicBlockList().push_back(MergeBB);
831 Builder.SetInsertPoint(MergeBB);
833 Builder.CreatePHI(Type::getDoubleTy(getGlobalContext()), 2, "iftmp");
835 PN->addIncoming(ThenV, ThenBB);
836 PN->addIncoming(ElseV, ElseBB);
840 Value *ForExprAST::Codegen() {
842 // var = alloca double
845 // store start -> var
856 // nextvar = curvar + step
857 // store nextvar -> var
858 // br endcond, loop, endloop
861 Function *TheFunction = Builder.GetInsertBlock()->getParent();
863 // Create an alloca for the variable in the entry block.
864 AllocaInst *Alloca = CreateEntryBlockAlloca(TheFunction, VarName);
866 // Emit the start code first, without 'variable' in scope.
867 Value *StartVal = Start->Codegen();
871 // Store the value into the alloca.
872 Builder.CreateStore(StartVal, Alloca);
874 // Make the new basic block for the loop header, inserting after current
877 BasicBlock::Create(getGlobalContext(), "loop", TheFunction);
879 // Insert an explicit fall through from the current block to the LoopBB.
880 Builder.CreateBr(LoopBB);
882 // Start insertion in LoopBB.
883 Builder.SetInsertPoint(LoopBB);
885 // Within the loop, the variable is defined equal to the PHI node. If it
886 // shadows an existing variable, we have to restore it, so save it now.
887 AllocaInst *OldVal = NamedValues[VarName];
888 NamedValues[VarName] = Alloca;
890 // Emit the body of the loop. This, like any other expr, can change the
891 // current BB. Note that we ignore the value computed by the body, but don't
893 if (Body->Codegen() == 0)
896 // Emit the step value.
899 StepVal = Step->Codegen();
903 // If not specified, use 1.0.
904 StepVal = ConstantFP::get(getGlobalContext(), APFloat(1.0));
907 // Compute the end condition.
908 Value *EndCond = End->Codegen();
912 // Reload, increment, and restore the alloca. This handles the case where
913 // the body of the loop mutates the variable.
914 Value *CurVar = Builder.CreateLoad(Alloca, VarName.c_str());
915 Value *NextVar = Builder.CreateFAdd(CurVar, StepVal, "nextvar");
916 Builder.CreateStore(NextVar, Alloca);
918 // Convert condition to a bool by comparing equal to 0.0.
919 EndCond = Builder.CreateFCmpONE(
920 EndCond, ConstantFP::get(getGlobalContext(), APFloat(0.0)), "loopcond");
922 // Create the "after loop" block and insert it.
923 BasicBlock *AfterBB =
924 BasicBlock::Create(getGlobalContext(), "afterloop", TheFunction);
926 // Insert the conditional branch into the end of LoopEndBB.
927 Builder.CreateCondBr(EndCond, LoopBB, AfterBB);
929 // Any new code will be inserted in AfterBB.
930 Builder.SetInsertPoint(AfterBB);
932 // Restore the unshadowed variable.
934 NamedValues[VarName] = OldVal;
936 NamedValues.erase(VarName);
938 // for expr always returns 0.0.
939 return Constant::getNullValue(Type::getDoubleTy(getGlobalContext()));
942 Value *VarExprAST::Codegen() {
943 std::vector<AllocaInst *> OldBindings;
945 Function *TheFunction = Builder.GetInsertBlock()->getParent();
947 // Register all variables and emit their initializer.
948 for (unsigned i = 0, e = VarNames.size(); i != e; ++i) {
949 const std::string &VarName = VarNames[i].first;
950 ExprAST *Init = VarNames[i].second;
952 // Emit the initializer before adding the variable to scope, this prevents
953 // the initializer from referencing the variable itself, and permits stuff
956 // var a = a in ... # refers to outer 'a'.
959 InitVal = Init->Codegen();
962 } else { // If not specified, use 0.0.
963 InitVal = ConstantFP::get(getGlobalContext(), APFloat(0.0));
966 AllocaInst *Alloca = CreateEntryBlockAlloca(TheFunction, VarName);
967 Builder.CreateStore(InitVal, Alloca);
969 // Remember the old variable binding so that we can restore the binding when
971 OldBindings.push_back(NamedValues[VarName]);
973 // Remember this binding.
974 NamedValues[VarName] = Alloca;
977 // Codegen the body, now that all vars are in scope.
978 Value *BodyVal = Body->Codegen();
982 // Pop all our variables from scope.
983 for (unsigned i = 0, e = VarNames.size(); i != e; ++i)
984 NamedValues[VarNames[i].first] = OldBindings[i];
986 // Return the body computation.
990 Function *PrototypeAST::Codegen() {
991 // Make the function type: double(double,double) etc.
992 std::vector<Type *> Doubles(Args.size(),
993 Type::getDoubleTy(getGlobalContext()));
995 FunctionType::get(Type::getDoubleTy(getGlobalContext()), Doubles, false);
998 Function::Create(FT, Function::ExternalLinkage, Name, TheModule);
1000 // If F conflicted, there was already something named 'Name'. If it has a
1001 // body, don't allow redefinition or reextern.
1002 if (F->getName() != Name) {
1003 // Delete the one we just made and get the existing one.
1004 F->eraseFromParent();
1005 F = TheModule->getFunction(Name);
1007 // If F already has a body, reject this.
1009 ErrorF("redefinition of function");
1013 // If F took a different number of args, reject.
1014 if (F->arg_size() != Args.size()) {
1015 ErrorF("redefinition of function with different # args");
1020 // Set names for all arguments.
1022 for (Function::arg_iterator AI = F->arg_begin(); Idx != Args.size();
1024 AI->setName(Args[Idx]);
1029 /// CreateArgumentAllocas - Create an alloca for each argument and register the
1030 /// argument in the symbol table so that references to it will succeed.
1031 void PrototypeAST::CreateArgumentAllocas(Function *F) {
1032 Function::arg_iterator AI = F->arg_begin();
1033 for (unsigned Idx = 0, e = Args.size(); Idx != e; ++Idx, ++AI) {
1034 // Create an alloca for this variable.
1035 AllocaInst *Alloca = CreateEntryBlockAlloca(F, Args[Idx]);
1037 // Store the initial value into the alloca.
1038 Builder.CreateStore(AI, Alloca);
1040 // Add arguments to variable symbol table.
1041 NamedValues[Args[Idx]] = Alloca;
1045 Function *FunctionAST::Codegen() {
1046 NamedValues.clear();
1048 Function *TheFunction = Proto->Codegen();
1049 if (TheFunction == 0)
1052 // If this is an operator, install it.
1053 if (Proto->isBinaryOp())
1054 BinopPrecedence[Proto->getOperatorName()] = Proto->getBinaryPrecedence();
1056 // Create a new basic block to start insertion into.
1057 BasicBlock *BB = BasicBlock::Create(getGlobalContext(), "entry", TheFunction);
1058 Builder.SetInsertPoint(BB);
1060 // Add all arguments to the symbol table and create their allocas.
1061 Proto->CreateArgumentAllocas(TheFunction);
1063 if (Value *RetVal = Body->Codegen()) {
1064 // Finish off the function.
1065 Builder.CreateRet(RetVal);
1067 // Validate the generated code, checking for consistency.
1068 verifyFunction(*TheFunction);
1070 // Optimize the function.
1071 TheFPM->run(*TheFunction);
1076 // Error reading body, remove function.
1077 TheFunction->eraseFromParent();
1079 if (Proto->isBinaryOp())
1080 BinopPrecedence.erase(Proto->getOperatorName());
1084 //===----------------------------------------------------------------------===//
1085 // Top-Level parsing and JIT Driver
1086 //===----------------------------------------------------------------------===//
1088 static ExecutionEngine *TheExecutionEngine;
1090 static void HandleDefinition() {
1091 if (FunctionAST *F = ParseDefinition()) {
1092 if (Function *LF = F->Codegen()) {
1093 fprintf(stderr, "Read function definition:");
1097 // Skip token for error recovery.
1102 static void HandleExtern() {
1103 if (PrototypeAST *P = ParseExtern()) {
1104 if (Function *F = P->Codegen()) {
1105 fprintf(stderr, "Read extern: ");
1109 // Skip token for error recovery.
1114 static void HandleTopLevelExpression() {
1115 // Evaluate a top-level expression into an anonymous function.
1116 if (FunctionAST *F = ParseTopLevelExpr()) {
1117 if (Function *LF = F->Codegen()) {
1118 TheExecutionEngine->finalizeObject();
1119 // JIT the function, returning a function pointer.
1120 void *FPtr = TheExecutionEngine->getPointerToFunction(LF);
1122 // Cast it to the right type (takes no arguments, returns a double) so we
1123 // can call it as a native function.
1124 double (*FP)() = (double (*)())(intptr_t)FPtr;
1125 fprintf(stderr, "Evaluated to %f\n", FP());
1128 // Skip token for error recovery.
1133 /// top ::= definition | external | expression | ';'
1134 static void MainLoop() {
1136 fprintf(stderr, "ready> ");
1142 break; // ignore top-level semicolons.
1150 HandleTopLevelExpression();
1156 //===----------------------------------------------------------------------===//
1157 // "Library" functions that can be "extern'd" from user code.
1158 //===----------------------------------------------------------------------===//
1160 /// putchard - putchar that takes a double and returns 0.
1161 extern "C" double putchard(double X) {
1166 /// printd - printf that takes a double prints it as "%f\n", returning 0.
1167 extern "C" double printd(double X) {
1172 //===----------------------------------------------------------------------===//
1173 // Main driver code.
1174 //===----------------------------------------------------------------------===//
1177 InitializeNativeTarget();
1178 InitializeNativeTargetAsmPrinter();
1179 InitializeNativeTargetAsmParser();
1180 LLVMContext &Context = getGlobalContext();
1182 // Install standard binary operators.
1183 // 1 is lowest precedence.
1184 BinopPrecedence['='] = 2;
1185 BinopPrecedence['<'] = 10;
1186 BinopPrecedence['+'] = 20;
1187 BinopPrecedence['-'] = 20;
1188 BinopPrecedence['*'] = 40; // highest.
1190 // Prime the first token.
1191 fprintf(stderr, "ready> ");
1194 // Make the module, which holds all the code.
1195 std::unique_ptr<Module> Owner = make_unique<Module>("my cool jit", Context);
1196 TheModule = Owner.get();
1198 // Create the JIT. This takes ownership of the module.
1200 TheExecutionEngine =
1201 EngineBuilder(std::move(Owner))
1202 .setErrorStr(&ErrStr)
1203 .setMCJITMemoryManager(llvm::make_unique<SectionMemoryManager>())
1205 if (!TheExecutionEngine) {
1206 fprintf(stderr, "Could not create ExecutionEngine: %s\n", ErrStr.c_str());
1210 legacy::FunctionPassManager OurFPM(TheModule);
1212 // Set up the optimizer pipeline. Start with registering info about how the
1213 // target lays out data structures.
1214 TheModule->setDataLayout(*TheExecutionEngine->getDataLayout());
1215 // Provide basic AliasAnalysis support for GVN.
1216 OurFPM.add(createBasicAliasAnalysisPass());
1217 // Promote allocas to registers.
1218 OurFPM.add(createPromoteMemoryToRegisterPass());
1219 // Do simple "peephole" optimizations and bit-twiddling optzns.
1220 OurFPM.add(createInstructionCombiningPass());
1221 // Reassociate expressions.
1222 OurFPM.add(createReassociatePass());
1223 // Eliminate Common SubExpressions.
1224 OurFPM.add(createGVNPass());
1225 // Simplify the control flow graph (deleting unreachable blocks, etc).
1226 OurFPM.add(createCFGSimplificationPass());
1228 OurFPM.doInitialization();
1230 // Set the global so the code gen can use this.
1233 // Run the main "interpreter loop" now.
1238 // Print out all of the generated code.