summaryrefslogtreecommitdiffstats
path: root/gnu/llvm/examples/Kaleidoscope/Chapter2/toy.cpp
diff options
context:
space:
mode:
authorpascal <pascal@openbsd.org>2016-09-03 22:46:54 +0000
committerpascal <pascal@openbsd.org>2016-09-03 22:46:54 +0000
commitb5500b9ca0102f1ccaf32f0e77e96d0739aded9b (patch)
treee1b7ebb5a0231f9e6d8d3f6f719582cebd64dc98 /gnu/llvm/examples/Kaleidoscope/Chapter2/toy.cpp
parentclarify purpose of src/gnu/ directory. (diff)
downloadwireguard-openbsd-b5500b9ca0102f1ccaf32f0e77e96d0739aded9b.tar.xz
wireguard-openbsd-b5500b9ca0102f1ccaf32f0e77e96d0739aded9b.zip
Use the space freed up by sparc and zaurus to import LLVM.
ok hackroom@
Diffstat (limited to 'gnu/llvm/examples/Kaleidoscope/Chapter2/toy.cpp')
-rw-r--r--gnu/llvm/examples/Kaleidoscope/Chapter2/toy.cpp451
1 files changed, 451 insertions, 0 deletions
diff --git a/gnu/llvm/examples/Kaleidoscope/Chapter2/toy.cpp b/gnu/llvm/examples/Kaleidoscope/Chapter2/toy.cpp
new file mode 100644
index 00000000000..69f35996129
--- /dev/null
+++ b/gnu/llvm/examples/Kaleidoscope/Chapter2/toy.cpp
@@ -0,0 +1,451 @@
+#include <cctype>
+#include <cstdio>
+#include <map>
+#include <memory>
+#include <string>
+#include <vector>
+
+namespace helper {
+// Cloning make_unique here until it's standard in C++14.
+// Using a namespace to avoid conflicting with MSVC's std::make_unique (which
+// ADL can sometimes find in unqualified calls).
+template <class T, class... Args>
+static
+ typename std::enable_if<!std::is_array<T>::value, std::unique_ptr<T>>::type
+ make_unique(Args &&... args) {
+ return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
+}
+}
+
+//===----------------------------------------------------------------------===//
+// Lexer
+//===----------------------------------------------------------------------===//
+
+// The lexer returns tokens [0-255] if it is an unknown character, otherwise one
+// of these for known things.
+enum Token {
+ tok_eof = -1,
+
+ // commands
+ tok_def = -2,
+ tok_extern = -3,
+
+ // primary
+ tok_identifier = -4,
+ tok_number = -5
+};
+
+static std::string IdentifierStr; // Filled in if tok_identifier
+static double NumVal; // Filled in if tok_number
+
+/// gettok - Return the next token from standard input.
+static int gettok() {
+ static int LastChar = ' ';
+
+ // Skip any whitespace.
+ while (isspace(LastChar))
+ LastChar = getchar();
+
+ if (isalpha(LastChar)) { // identifier: [a-zA-Z][a-zA-Z0-9]*
+ IdentifierStr = LastChar;
+ while (isalnum((LastChar = getchar())))
+ IdentifierStr += LastChar;
+
+ if (IdentifierStr == "def")
+ return tok_def;
+ if (IdentifierStr == "extern")
+ return tok_extern;
+ return tok_identifier;
+ }
+
+ if (isdigit(LastChar) || LastChar == '.') { // Number: [0-9.]+
+ std::string NumStr;
+ do {
+ NumStr += LastChar;
+ LastChar = getchar();
+ } while (isdigit(LastChar) || LastChar == '.');
+
+ NumVal = strtod(NumStr.c_str(), nullptr);
+ return tok_number;
+ }
+
+ if (LastChar == '#') {
+ // Comment until end of line.
+ do
+ LastChar = getchar();
+ while (LastChar != EOF && LastChar != '\n' && LastChar != '\r');
+
+ if (LastChar != EOF)
+ return gettok();
+ }
+
+ // Check for end of file. Don't eat the EOF.
+ if (LastChar == EOF)
+ return tok_eof;
+
+ // Otherwise, just return the character as its ascii value.
+ int ThisChar = LastChar;
+ LastChar = getchar();
+ return ThisChar;
+}
+
+//===----------------------------------------------------------------------===//
+// Abstract Syntax Tree (aka Parse Tree)
+//===----------------------------------------------------------------------===//
+namespace {
+/// ExprAST - Base class for all expression nodes.
+class ExprAST {
+public:
+ virtual ~ExprAST() {}
+};
+
+/// NumberExprAST - Expression class for numeric literals like "1.0".
+class NumberExprAST : public ExprAST {
+ double Val;
+
+public:
+ NumberExprAST(double Val) : Val(Val) {}
+};
+
+/// VariableExprAST - Expression class for referencing a variable, like "a".
+class VariableExprAST : public ExprAST {
+ std::string Name;
+
+public:
+ VariableExprAST(const std::string &Name) : Name(Name) {}
+};
+
+/// BinaryExprAST - Expression class for a binary operator.
+class BinaryExprAST : public ExprAST {
+ char Op;
+ std::unique_ptr<ExprAST> LHS, RHS;
+
+public:
+ BinaryExprAST(char Op, std::unique_ptr<ExprAST> LHS,
+ std::unique_ptr<ExprAST> RHS)
+ : Op(Op), LHS(std::move(LHS)), RHS(std::move(RHS)) {}
+};
+
+/// CallExprAST - Expression class for function calls.
+class CallExprAST : public ExprAST {
+ std::string Callee;
+ std::vector<std::unique_ptr<ExprAST>> Args;
+
+public:
+ CallExprAST(const std::string &Callee,
+ std::vector<std::unique_ptr<ExprAST>> Args)
+ : Callee(Callee), Args(std::move(Args)) {}
+};
+
+/// PrototypeAST - This class represents the "prototype" for a function,
+/// which captures its name, and its argument names (thus implicitly the number
+/// of arguments the function takes).
+class PrototypeAST {
+ std::string Name;
+ std::vector<std::string> Args;
+
+public:
+ PrototypeAST(const std::string &Name, std::vector<std::string> Args)
+ : Name(Name), Args(std::move(Args)) {}
+};
+
+/// FunctionAST - This class represents a function definition itself.
+class FunctionAST {
+ std::unique_ptr<PrototypeAST> Proto;
+ std::unique_ptr<ExprAST> Body;
+
+public:
+ FunctionAST(std::unique_ptr<PrototypeAST> Proto,
+ std::unique_ptr<ExprAST> Body)
+ : Proto(std::move(Proto)), Body(std::move(Body)) {}
+};
+} // end anonymous namespace
+
+//===----------------------------------------------------------------------===//
+// Parser
+//===----------------------------------------------------------------------===//
+
+/// CurTok/getNextToken - Provide a simple token buffer. CurTok is the current
+/// token the parser is looking at. getNextToken reads another token from the
+/// lexer and updates CurTok with its results.
+static int CurTok;
+static int getNextToken() { return CurTok = gettok(); }
+
+/// BinopPrecedence - This holds the precedence for each binary operator that is
+/// defined.
+static std::map<char, int> BinopPrecedence;
+
+/// GetTokPrecedence - Get the precedence of the pending binary operator token.
+static int GetTokPrecedence() {
+ if (!isascii(CurTok))
+ return -1;
+
+ // Make sure it's a declared binop.
+ int TokPrec = BinopPrecedence[CurTok];
+ if (TokPrec <= 0)
+ return -1;
+ return TokPrec;
+}
+
+/// Error* - These are little helper functions for error handling.
+std::unique_ptr<ExprAST> Error(const char *Str) {
+ fprintf(stderr, "Error: %s\n", Str);
+ return nullptr;
+}
+std::unique_ptr<PrototypeAST> ErrorP(const char *Str) {
+ Error(Str);
+ return nullptr;
+}
+
+static std::unique_ptr<ExprAST> ParseExpression();
+
+/// numberexpr ::= number
+static std::unique_ptr<ExprAST> ParseNumberExpr() {
+ auto Result = helper::make_unique<NumberExprAST>(NumVal);
+ getNextToken(); // consume the number
+ return std::move(Result);
+}
+
+/// parenexpr ::= '(' expression ')'
+static std::unique_ptr<ExprAST> ParseParenExpr() {
+ getNextToken(); // eat (.
+ auto V = ParseExpression();
+ if (!V)
+ return nullptr;
+
+ if (CurTok != ')')
+ return Error("expected ')'");
+ getNextToken(); // eat ).
+ return V;
+}
+
+/// identifierexpr
+/// ::= identifier
+/// ::= identifier '(' expression* ')'
+static std::unique_ptr<ExprAST> ParseIdentifierExpr() {
+ std::string IdName = IdentifierStr;
+
+ getNextToken(); // eat identifier.
+
+ if (CurTok != '(') // Simple variable ref.
+ return helper::make_unique<VariableExprAST>(IdName);
+
+ // Call.
+ getNextToken(); // eat (
+ std::vector<std::unique_ptr<ExprAST>> Args;
+ if (CurTok != ')') {
+ while (1) {
+ if (auto Arg = ParseExpression())
+ Args.push_back(std::move(Arg));
+ else
+ return nullptr;
+
+ if (CurTok == ')')
+ break;
+
+ if (CurTok != ',')
+ return Error("Expected ')' or ',' in argument list");
+ getNextToken();
+ }
+ }
+
+ // Eat the ')'.
+ getNextToken();
+
+ return helper::make_unique<CallExprAST>(IdName, std::move(Args));
+}
+
+/// primary
+/// ::= identifierexpr
+/// ::= numberexpr
+/// ::= parenexpr
+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();
+ }
+}
+
+/// binoprhs
+/// ::= ('+' primary)*
+static std::unique_ptr<ExprAST> ParseBinOpRHS(int ExprPrec,
+ std::unique_ptr<ExprAST> LHS) {
+ // If this is a binop, find its precedence.
+ while (1) {
+ int TokPrec = GetTokPrecedence();
+
+ // If this is a binop that binds at least as tightly as the current binop,
+ // consume it, otherwise we are done.
+ if (TokPrec < ExprPrec)
+ return LHS;
+
+ // Okay, we know this is a binop.
+ int BinOp = CurTok;
+ getNextToken(); // eat binop
+
+ // Parse the primary expression after the binary operator.
+ auto RHS = ParsePrimary();
+ if (!RHS)
+ return nullptr;
+
+ // If BinOp binds less tightly with RHS than the operator after RHS, let
+ // the pending operator take RHS as its LHS.
+ int NextPrec = GetTokPrecedence();
+ if (TokPrec < NextPrec) {
+ RHS = ParseBinOpRHS(TokPrec + 1, std::move(RHS));
+ if (!RHS)
+ return nullptr;
+ }
+
+ // Merge LHS/RHS.
+ LHS = helper::make_unique<BinaryExprAST>(BinOp, std::move(LHS),
+ std::move(RHS));
+ }
+}
+
+/// expression
+/// ::= primary binoprhs
+///
+static std::unique_ptr<ExprAST> ParseExpression() {
+ auto LHS = ParsePrimary();
+ if (!LHS)
+ return nullptr;
+
+ return ParseBinOpRHS(0, std::move(LHS));
+}
+
+/// prototype
+/// ::= id '(' id* ')'
+static std::unique_ptr<PrototypeAST> ParsePrototype() {
+ if (CurTok != tok_identifier)
+ return ErrorP("Expected function name in prototype");
+
+ std::string FnName = IdentifierStr;
+ getNextToken();
+
+ if (CurTok != '(')
+ return ErrorP("Expected '(' in prototype");
+
+ std::vector<std::string> ArgNames;
+ while (getNextToken() == tok_identifier)
+ ArgNames.push_back(IdentifierStr);
+ if (CurTok != ')')
+ return ErrorP("Expected ')' in prototype");
+
+ // success.
+ getNextToken(); // eat ')'.
+
+ return helper::make_unique<PrototypeAST>(FnName, std::move(ArgNames));
+}
+
+/// definition ::= 'def' prototype expression
+static std::unique_ptr<FunctionAST> ParseDefinition() {
+ getNextToken(); // eat def.
+ auto Proto = ParsePrototype();
+ if (!Proto)
+ return nullptr;
+
+ if (auto E = ParseExpression())
+ return helper::make_unique<FunctionAST>(std::move(Proto), std::move(E));
+ return nullptr;
+}
+
+/// toplevelexpr ::= expression
+static std::unique_ptr<FunctionAST> ParseTopLevelExpr() {
+ if (auto E = ParseExpression()) {
+ // Make an anonymous proto.
+ auto Proto = helper::make_unique<PrototypeAST>("__anon_expr",
+ std::vector<std::string>());
+ return helper::make_unique<FunctionAST>(std::move(Proto), std::move(E));
+ }
+ return nullptr;
+}
+
+/// external ::= 'extern' prototype
+static std::unique_ptr<PrototypeAST> ParseExtern() {
+ getNextToken(); // eat extern.
+ return ParsePrototype();
+}
+
+//===----------------------------------------------------------------------===//
+// Top-Level parsing
+//===----------------------------------------------------------------------===//
+
+static void HandleDefinition() {
+ if (ParseDefinition()) {
+ fprintf(stderr, "Parsed a function definition.\n");
+ } else {
+ // Skip token for error recovery.
+ getNextToken();
+ }
+}
+
+static void HandleExtern() {
+ if (ParseExtern()) {
+ fprintf(stderr, "Parsed an extern\n");
+ } else {
+ // Skip token for error recovery.
+ getNextToken();
+ }
+}
+
+static void HandleTopLevelExpression() {
+ // Evaluate a top-level expression into an anonymous function.
+ if (ParseTopLevelExpr()) {
+ fprintf(stderr, "Parsed a top-level expr\n");
+ } else {
+ // Skip token for error recovery.
+ getNextToken();
+ }
+}
+
+/// top ::= definition | external | expression | ';'
+static void MainLoop() {
+ while (1) {
+ fprintf(stderr, "ready> ");
+ switch (CurTok) {
+ case tok_eof:
+ return;
+ case ';': // ignore top-level semicolons.
+ getNextToken();
+ break;
+ case tok_def:
+ HandleDefinition();
+ break;
+ case tok_extern:
+ HandleExtern();
+ break;
+ default:
+ HandleTopLevelExpression();
+ break;
+ }
+ }
+}
+
+//===----------------------------------------------------------------------===//
+// Main driver code.
+//===----------------------------------------------------------------------===//
+
+int main() {
+ // Install standard binary operators.
+ // 1 is lowest precedence.
+ BinopPrecedence['<'] = 10;
+ BinopPrecedence['+'] = 20;
+ BinopPrecedence['-'] = 20;
+ BinopPrecedence['*'] = 40; // highest.
+
+ // Prime the first token.
+ fprintf(stderr, "ready> ");
+ getNextToken();
+
+ // Run the main "interpreter loop" now.
+ MainLoop();
+
+ return 0;
+}