diff options
Diffstat (limited to 'examples/OCaml-Kaleidoscope/Chapter2')
| -rw-r--r-- | examples/OCaml-Kaleidoscope/Chapter2/Makefile | 22 | ||||
| -rw-r--r-- | examples/OCaml-Kaleidoscope/Chapter2/_tags | 1 | ||||
| -rw-r--r-- | examples/OCaml-Kaleidoscope/Chapter2/ast.ml | 25 | ||||
| -rw-r--r-- | examples/OCaml-Kaleidoscope/Chapter2/lexer.ml | 52 | ||||
| -rw-r--r-- | examples/OCaml-Kaleidoscope/Chapter2/parser.ml | 122 | ||||
| -rw-r--r-- | examples/OCaml-Kaleidoscope/Chapter2/token.ml | 15 | ||||
| -rw-r--r-- | examples/OCaml-Kaleidoscope/Chapter2/toplevel.ml | 34 | ||||
| -rw-r--r-- | examples/OCaml-Kaleidoscope/Chapter2/toy.ml | 21 |
8 files changed, 292 insertions, 0 deletions
diff --git a/examples/OCaml-Kaleidoscope/Chapter2/Makefile b/examples/OCaml-Kaleidoscope/Chapter2/Makefile new file mode 100644 index 0000000000..8fc03da0fb --- /dev/null +++ b/examples/OCaml-Kaleidoscope/Chapter2/Makefile @@ -0,0 +1,22 @@ +##===- examples/OCaml-Kaleidoscope/Chapter2/Makefile -------*- Makefile -*-===## +# +# The LLVM Compiler Infrastructure +# +# This file is distributed under the University of Illinois Open Source +# License. See LICENSE.TXT for details. +# +##===----------------------------------------------------------------------===## +# +# This is the makefile for the Objective Caml kaleidoscope tutorial, chapter 2. +# +##===----------------------------------------------------------------------===## + +LEVEL := ../../.. +TOOLNAME := OCaml-Kaleidoscope-Ch2 +EXAMPLE_TOOL := 1 +UsedComponents := core +UsedOcamLibs := llvm + +OCAMLCFLAGS += -pp camlp4of + +include $(LEVEL)/bindings/ocaml/Makefile.ocaml diff --git a/examples/OCaml-Kaleidoscope/Chapter2/_tags b/examples/OCaml-Kaleidoscope/Chapter2/_tags new file mode 100644 index 0000000000..7b9b80b1e9 --- /dev/null +++ b/examples/OCaml-Kaleidoscope/Chapter2/_tags @@ -0,0 +1 @@ +<{lexer,parser}.ml>: use_camlp4, pp(camlp4of) diff --git a/examples/OCaml-Kaleidoscope/Chapter2/ast.ml b/examples/OCaml-Kaleidoscope/Chapter2/ast.ml new file mode 100644 index 0000000000..4cc2dea86b --- /dev/null +++ b/examples/OCaml-Kaleidoscope/Chapter2/ast.ml @@ -0,0 +1,25 @@ +(*===----------------------------------------------------------------------=== + * Abstract Syntax Tree (aka Parse Tree) + *===----------------------------------------------------------------------===*) + +(* expr - Base type for all expression nodes. *) +type expr = + (* variant for numeric literals like "1.0". *) + | Number of float + + (* variant for referencing a variable, like "a". *) + | Variable of string + + (* variant for a binary operator. *) + | Binary of char * expr * expr + + (* variant for function calls. *) + | Call of string * expr array + +(* proto - This type represents the "prototype" for a function, which captures + * its name, and its argument names (thus implicitly the number of arguments the + * function takes). *) +type proto = Prototype of string * string array + +(* func - This type represents a function definition itself. *) +type func = Function of proto * expr diff --git a/examples/OCaml-Kaleidoscope/Chapter2/lexer.ml b/examples/OCaml-Kaleidoscope/Chapter2/lexer.ml new file mode 100644 index 0000000000..22a915552f --- /dev/null +++ b/examples/OCaml-Kaleidoscope/Chapter2/lexer.ml @@ -0,0 +1,52 @@ +(*===----------------------------------------------------------------------=== + * Lexer + *===----------------------------------------------------------------------===*) + +let rec lex = parser + (* Skip any whitespace. *) + | [< ' (' ' | '\n' | '\r' | '\t'); stream >] -> lex stream + + (* identifier: [a-zA-Z][a-zA-Z0-9] *) + | [< ' ('A' .. 'Z' | 'a' .. 'z' as c); stream >] -> + let buffer = Buffer.create 1 in + Buffer.add_char buffer c; + lex_ident buffer stream + + (* number: [0-9.]+ *) + | [< ' ('0' .. '9' as c); stream >] -> + let buffer = Buffer.create 1 in + Buffer.add_char buffer c; + lex_number buffer stream + + (* Comment until end of line. *) + | [< ' ('#'); stream >] -> + lex_comment stream + + (* Otherwise, just return the character as its ascii value. *) + | [< 'c; stream >] -> + [< 'Token.Kwd c; lex stream >] + + (* end of stream. *) + | [< >] -> [< >] + +and lex_number buffer = parser + | [< ' ('0' .. '9' | '.' as c); stream >] -> + Buffer.add_char buffer c; + lex_number buffer stream + | [< stream=lex >] -> + [< 'Token.Number (float_of_string (Buffer.contents buffer)); stream >] + +and lex_ident buffer = parser + | [< ' ('A' .. 'Z' | 'a' .. 'z' | '0' .. '9' as c); stream >] -> + Buffer.add_char buffer c; + lex_ident buffer stream + | [< stream=lex >] -> + match Buffer.contents buffer with + | "def" -> [< 'Token.Def; stream >] + | "extern" -> [< 'Token.Extern; stream >] + | id -> [< 'Token.Ident id; stream >] + +and lex_comment = parser + | [< ' ('\n'); stream=lex >] -> stream + | [< 'c; e=lex_comment >] -> e + | [< >] -> [< >] diff --git a/examples/OCaml-Kaleidoscope/Chapter2/parser.ml b/examples/OCaml-Kaleidoscope/Chapter2/parser.ml new file mode 100644 index 0000000000..83d9874a4a --- /dev/null +++ b/examples/OCaml-Kaleidoscope/Chapter2/parser.ml @@ -0,0 +1,122 @@ +(*===---------------------------------------------------------------------=== + * Parser + *===---------------------------------------------------------------------===*) + +(* binop_precedence - This holds the precedence for each binary operator that is + * defined *) +let binop_precedence:(char, int) Hashtbl.t = Hashtbl.create 10 + +(* precedence - Get the precedence of the pending binary operator token. *) +let precedence c = try Hashtbl.find binop_precedence c with Not_found -> -1 + +(* primary + * ::= identifier + * ::= numberexpr + * ::= parenexpr *) +let rec parse_primary = parser + (* numberexpr ::= number *) + | [< 'Token.Number n >] -> Ast.Number n + + (* parenexpr ::= '(' expression ')' *) + | [< 'Token.Kwd '('; e=parse_expr; 'Token.Kwd ')' ?? "expected ')'" >] -> e + + (* identifierexpr + * ::= identifier + * ::= identifier '(' argumentexpr ')' *) + | [< 'Token.Ident id; stream >] -> + let rec parse_args accumulator = parser + | [< e=parse_expr; stream >] -> + begin parser + | [< 'Token.Kwd ','; e=parse_args (e :: accumulator) >] -> e + | [< >] -> e :: accumulator + end stream + | [< >] -> accumulator + in + let rec parse_ident id = parser + (* Call. *) + | [< 'Token.Kwd '('; + args=parse_args []; + 'Token.Kwd ')' ?? "expected ')'">] -> + Ast.Call (id, Array.of_list (List.rev args)) + + (* Simple variable ref. *) + | [< >] -> Ast.Variable id + in + parse_ident id stream + + | [< >] -> raise (Stream.Error "unknown token when expecting an expression.") + +(* binoprhs + * ::= ('+' primary)* *) +and parse_bin_rhs expr_prec lhs stream = + match Stream.peek stream with + (* If this is a binop, find its precedence. *) + | Some (Token.Kwd c) when Hashtbl.mem binop_precedence c -> + let token_prec = precedence c in + + (* If this is a binop that binds at least as tightly as the current binop, + * consume it, otherwise we are done. *) + if token_prec < expr_prec then lhs else begin + (* Eat the binop. *) + Stream.junk stream; + + (* Parse the primary expression after the binary operator. *) + let rhs = parse_primary stream in + + (* Okay, we know this is a binop. *) + let rhs = + match Stream.peek stream with + | Some (Token.Kwd c2) -> + (* If BinOp binds less tightly with rhs than the operator after + * rhs, let the pending operator take rhs as its lhs. *) + let next_prec = precedence c2 in + if token_prec < next_prec + then parse_bin_rhs (token_prec + 1) rhs stream + else rhs + | _ -> rhs + in + + (* Merge lhs/rhs. *) + let lhs = Ast.Binary (c, lhs, rhs) in + parse_bin_rhs expr_prec lhs stream + end + | _ -> lhs + +(* expression + * ::= primary binoprhs *) +and parse_expr = parser + | [< lhs=parse_primary; stream >] -> parse_bin_rhs 0 lhs stream + +(* prototype + * ::= id '(' id* ')' *) +let parse_prototype = + let rec parse_args accumulator = parser + | [< 'Token.Ident id; e=parse_args (id::accumulator) >] -> e + | [< >] -> accumulator + in + + parser + | [< 'Token.Ident id; + 'Token.Kwd '(' ?? "expected '(' in prototype"; + args=parse_args []; + 'Token.Kwd ')' ?? "expected ')' in prototype" >] -> + (* success. *) + Ast.Prototype (id, Array.of_list (List.rev args)) + + | [< >] -> + raise (Stream.Error "expected function name in prototype") + +(* definition ::= 'def' prototype expression *) +let parse_definition = parser + | [< 'Token.Def; p=parse_prototype; e=parse_expr >] -> + Ast.Function (p, e) + +(* toplevelexpr ::= expression *) +let parse_toplevel = parser + | [< e=parse_expr >] -> + (* Make an anonymous proto. *) + Ast.Function (Ast.Prototype ("", [||]), e) + +(* external ::= 'extern' prototype *) +let parse_extern = parser + | [< 'Token.Extern; e=parse_prototype >] -> e diff --git a/examples/OCaml-Kaleidoscope/Chapter2/token.ml b/examples/OCaml-Kaleidoscope/Chapter2/token.ml new file mode 100644 index 0000000000..2ca782e149 --- /dev/null +++ b/examples/OCaml-Kaleidoscope/Chapter2/token.ml @@ -0,0 +1,15 @@ +(*===----------------------------------------------------------------------=== + * Lexer Tokens + *===----------------------------------------------------------------------===*) + +(* The lexer returns these 'Kwd' if it is an unknown character, otherwise one of + * these others for known things. *) +type token = + (* commands *) + | Def | Extern + + (* primary *) + | Ident of string | Number of float + + (* unknown *) + | Kwd of char diff --git a/examples/OCaml-Kaleidoscope/Chapter2/toplevel.ml b/examples/OCaml-Kaleidoscope/Chapter2/toplevel.ml new file mode 100644 index 0000000000..01c85bd70d --- /dev/null +++ b/examples/OCaml-Kaleidoscope/Chapter2/toplevel.ml @@ -0,0 +1,34 @@ +(*===----------------------------------------------------------------------=== + * Top-Level parsing and JIT Driver + *===----------------------------------------------------------------------===*) + +(* top ::= definition | external | expression | ';' *) +let rec main_loop stream = + match Stream.peek stream with + | None -> () + + (* ignore top-level semicolons. *) + | Some (Token.Kwd ';') -> + Stream.junk stream; + main_loop stream + + | Some token -> + begin + try match token with + | Token.Def -> + ignore(Parser.parse_definition stream); + print_endline "parsed a function definition."; + | Token.Extern -> + ignore(Parser.parse_extern stream); + print_endline "parsed an extern."; + | _ -> + (* Evaluate a top-level expression into an anonymous function. *) + ignore(Parser.parse_toplevel stream); + print_endline "parsed a top-level expr"; + with Stream.Error s -> + (* Skip token for error recovery. *) + Stream.junk stream; + print_endline s; + end; + print_string "ready> "; flush stdout; + main_loop stream diff --git a/examples/OCaml-Kaleidoscope/Chapter2/toy.ml b/examples/OCaml-Kaleidoscope/Chapter2/toy.ml new file mode 100644 index 0000000000..42b19fec00 --- /dev/null +++ b/examples/OCaml-Kaleidoscope/Chapter2/toy.ml @@ -0,0 +1,21 @@ +(*===----------------------------------------------------------------------=== + * Main driver code. + *===----------------------------------------------------------------------===*) + +let main () = + (* Install standard binary operators. + * 1 is the lowest precedence. *) + Hashtbl.add Parser.binop_precedence '<' 10; + Hashtbl.add Parser.binop_precedence '+' 20; + Hashtbl.add Parser.binop_precedence '-' 20; + Hashtbl.add Parser.binop_precedence '*' 40; (* highest. *) + + (* Prime the first token. *) + print_string "ready> "; flush stdout; + let stream = Lexer.lex (Stream.of_channel stdin) in + + (* Run the main "interpreter loop" now. *) + Toplevel.main_loop stream; +;; + +main () |