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      1 (*===----------------------------------------------------------------------===
      2  * Main driver code.
      3  *===----------------------------------------------------------------------===*)
      4 
      5 open Llvm
      6 open Llvm_executionengine
      7 open Llvm_target
      8 open Llvm_scalar_opts
      9 
     10 let main () =
     11   ignore (initialize_native_target ());
     12 
     13   (* Install standard binary operators.
     14    * 1 is the lowest precedence. *)
     15   Hashtbl.add Parser.binop_precedence '<' 10;
     16   Hashtbl.add Parser.binop_precedence '+' 20;
     17   Hashtbl.add Parser.binop_precedence '-' 20;
     18   Hashtbl.add Parser.binop_precedence '*' 40;    (* highest. *)
     19 
     20   (* Prime the first token. *)
     21   print_string "ready> "; flush stdout;
     22   let stream = Lexer.lex (Stream.of_channel stdin) in
     23 
     24   (* Create the JIT. *)
     25   let the_execution_engine = ExecutionEngine.create Codegen.the_module in
     26   let the_fpm = PassManager.create_function Codegen.the_module in
     27 
     28   (* Set up the optimizer pipeline.  Start with registering info about how the
     29    * target lays out data structures. *)
     30   DataLayout.add (ExecutionEngine.target_data the_execution_engine) the_fpm;
     31 
     32   (* Do simple "peephole" optimizations and bit-twiddling optzn. *)
     33   add_instruction_combination the_fpm;
     34 
     35   (* reassociate expressions. *)
     36   add_reassociation the_fpm;
     37 
     38   (* Eliminate Common SubExpressions. *)
     39   add_gvn the_fpm;
     40 
     41   (* Simplify the control flow graph (deleting unreachable blocks, etc). *)
     42   add_cfg_simplification the_fpm;
     43 
     44   ignore (PassManager.initialize the_fpm);
     45 
     46   (* Run the main "interpreter loop" now. *)
     47   Toplevel.main_loop the_fpm the_execution_engine stream;
     48 
     49   (* Print out all the generated code. *)
     50   dump_module Codegen.the_module
     51 ;;
     52 
     53 main ()
     54