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Diffstat (limited to 'contrib/llvm/examples/OCaml-Kaleidoscope/Chapter5/codegen.ml')
| -rw-r--r-- | contrib/llvm/examples/OCaml-Kaleidoscope/Chapter5/codegen.ml | 225 |
1 files changed, 0 insertions, 225 deletions
diff --git a/contrib/llvm/examples/OCaml-Kaleidoscope/Chapter5/codegen.ml b/contrib/llvm/examples/OCaml-Kaleidoscope/Chapter5/codegen.ml deleted file mode 100644 index e0db2d2..0000000 --- a/contrib/llvm/examples/OCaml-Kaleidoscope/Chapter5/codegen.ml +++ /dev/null @@ -1,225 +0,0 @@ -(*===----------------------------------------------------------------------=== - * Code Generation - *===----------------------------------------------------------------------===*) - -open Llvm - -exception Error of string - -let context = global_context () -let the_module = create_module context "my cool jit" -let builder = builder context -let named_values:(string, llvalue) Hashtbl.t = Hashtbl.create 10 -let double_type = double_type context - -let rec codegen_expr = function - | Ast.Number n -> const_float double_type n - | Ast.Variable name -> - (try Hashtbl.find named_values name with - | Not_found -> raise (Error "unknown variable name")) - | Ast.Binary (op, lhs, rhs) -> - let lhs_val = codegen_expr lhs in - let rhs_val = codegen_expr rhs in - begin - match op with - | '+' -> build_add lhs_val rhs_val "addtmp" builder - | '-' -> build_sub lhs_val rhs_val "subtmp" builder - | '*' -> build_mul lhs_val rhs_val "multmp" builder - | '<' -> - (* Convert bool 0/1 to double 0.0 or 1.0 *) - let i = build_fcmp Fcmp.Ult lhs_val rhs_val "cmptmp" builder in - build_uitofp i double_type "booltmp" builder - | _ -> raise (Error "invalid binary operator") - end - | Ast.Call (callee, args) -> - (* Look up the name in the module table. *) - let callee = - match lookup_function callee the_module with - | Some callee -> callee - | None -> raise (Error "unknown function referenced") - in - let params = params callee in - - (* If argument mismatch error. *) - if Array.length params == Array.length args then () else - raise (Error "incorrect # arguments passed"); - let args = Array.map codegen_expr args in - build_call callee args "calltmp" builder - | Ast.If (cond, then_, else_) -> - let cond = codegen_expr cond in - - (* Convert condition to a bool by comparing equal to 0.0 *) - let zero = const_float double_type 0.0 in - let cond_val = build_fcmp Fcmp.One cond zero "ifcond" builder in - - (* Grab the first block so that we might later add the conditional branch - * to it at the end of the function. *) - let start_bb = insertion_block builder in - let the_function = block_parent start_bb in - - let then_bb = append_block context "then" the_function in - - (* Emit 'then' value. *) - position_at_end then_bb builder; - let then_val = codegen_expr then_ in - - (* Codegen of 'then' can change the current block, update then_bb for the - * phi. We create a new name because one is used for the phi node, and the - * other is used for the conditional branch. *) - let new_then_bb = insertion_block builder in - - (* Emit 'else' value. *) - let else_bb = append_block context "else" the_function in - position_at_end else_bb builder; - let else_val = codegen_expr else_ in - - (* Codegen of 'else' can change the current block, update else_bb for the - * phi. *) - let new_else_bb = insertion_block builder in - - (* Emit merge block. *) - let merge_bb = append_block context "ifcont" the_function in - position_at_end merge_bb builder; - let incoming = [(then_val, new_then_bb); (else_val, new_else_bb)] in - let phi = build_phi incoming "iftmp" builder in - - (* Return to the start block to add the conditional branch. *) - position_at_end start_bb builder; - ignore (build_cond_br cond_val then_bb else_bb builder); - - (* Set a unconditional branch at the end of the 'then' block and the - * 'else' block to the 'merge' block. *) - position_at_end new_then_bb builder; ignore (build_br merge_bb builder); - position_at_end new_else_bb builder; ignore (build_br merge_bb builder); - - (* Finally, set the builder to the end of the merge block. *) - position_at_end merge_bb builder; - - phi - | Ast.For (var_name, start, end_, step, body) -> - (* Emit the start code first, without 'variable' in scope. *) - let start_val = codegen_expr start in - - (* Make the new basic block for the loop header, inserting after current - * block. *) - let preheader_bb = insertion_block builder in - let the_function = block_parent preheader_bb in - let loop_bb = append_block context "loop" the_function in - - (* Insert an explicit fall through from the current block to the - * loop_bb. *) - ignore (build_br loop_bb builder); - - (* Start insertion in loop_bb. *) - position_at_end loop_bb builder; - - (* Start the PHI node with an entry for start. *) - let variable = build_phi [(start_val, preheader_bb)] var_name builder in - - (* Within the loop, the variable is defined equal to the PHI node. If it - * shadows an existing variable, we have to restore it, so save it - * now. *) - let old_val = - try Some (Hashtbl.find named_values var_name) with Not_found -> None - in - Hashtbl.add named_values var_name variable; - - (* Emit the body of the loop. This, like any other expr, can change the - * current BB. Note that we ignore the value computed by the body, but - * don't allow an error *) - ignore (codegen_expr body); - - (* Emit the step value. *) - let step_val = - match step with - | Some step -> codegen_expr step - (* If not specified, use 1.0. *) - | None -> const_float double_type 1.0 - in - - let next_var = build_add variable step_val "nextvar" builder in - - (* Compute the end condition. *) - let end_cond = codegen_expr end_ in - - (* Convert condition to a bool by comparing equal to 0.0. *) - let zero = const_float double_type 0.0 in - let end_cond = build_fcmp Fcmp.One end_cond zero "loopcond" builder in - - (* Create the "after loop" block and insert it. *) - let loop_end_bb = insertion_block builder in - let after_bb = append_block context "afterloop" the_function in - - (* Insert the conditional branch into the end of loop_end_bb. *) - ignore (build_cond_br end_cond loop_bb after_bb builder); - - (* Any new code will be inserted in after_bb. *) - position_at_end after_bb builder; - - (* Add a new entry to the PHI node for the backedge. *) - add_incoming (next_var, loop_end_bb) variable; - - (* Restore the unshadowed variable. *) - begin match old_val with - | Some old_val -> Hashtbl.add named_values var_name old_val - | None -> () - end; - - (* for expr always returns 0.0. *) - const_null double_type - -let codegen_proto = function - | Ast.Prototype (name, args) -> - (* Make the function type: double(double,double) etc. *) - let doubles = Array.make (Array.length args) double_type in - let ft = function_type double_type doubles in - let f = - match lookup_function name the_module with - | None -> declare_function name ft the_module - - (* If 'f' conflicted, there was already something named 'name'. If it - * has a body, don't allow redefinition or reextern. *) - | Some f -> - (* If 'f' already has a body, reject this. *) - if block_begin f <> At_end f then - raise (Error "redefinition of function"); - - (* If 'f' took a different number of arguments, reject. *) - if element_type (type_of f) <> ft then - raise (Error "redefinition of function with different # args"); - f - in - - (* Set names for all arguments. *) - Array.iteri (fun i a -> - let n = args.(i) in - set_value_name n a; - Hashtbl.add named_values n a; - ) (params f); - f - -let codegen_func the_fpm = function - | Ast.Function (proto, body) -> - Hashtbl.clear named_values; - let the_function = codegen_proto proto in - - (* Create a new basic block to start insertion into. *) - let bb = append_block context "entry" the_function in - position_at_end bb builder; - - try - let ret_val = codegen_expr body in - - (* Finish off the function. *) - let _ = build_ret ret_val builder in - - (* Validate the generated code, checking for consistency. *) - Llvm_analysis.assert_valid_function the_function; - - (* Optimize the function. *) - let _ = PassManager.run_function the_function the_fpm in - - the_function - with e -> - delete_function the_function; - raise e |
