diff options
Diffstat (limited to 'src/codegen.ml')
-rw-r--r-- | src/codegen.ml | 191 |
1 files changed, 120 insertions, 71 deletions
diff --git a/src/codegen.ml b/src/codegen.ml index 5042339..6ada77a 100644 --- a/src/codegen.ml +++ b/src/codegen.ml @@ -3,6 +3,8 @@ open Typing exception Very_bad_error of string +exception Reference_register of register + (* Convention pour les registres : - a0, a1, a2, a3 : contiennent les (éventuels) 4 premiers arguments de la fonction - v0 : contient la valeur de retour des fonctions (rien de particulier pour un constructeur) @@ -35,6 +37,7 @@ type cg_env = { c_fp_used : int; c_need_fp : bool ref; c_save_regs : register list; + c_free_regs : register list; } let env_push n e = @@ -46,6 +49,7 @@ let env_push n e = c_ret_lbl = e.c_ret_lbl; c_need_fp = e.c_need_fp; c_fp_used = kk; + c_free_regs = e.c_free_regs; c_save_regs = e.c_save_regs }, -kk let env_add_var vid vv e = @@ -54,9 +58,21 @@ let env_add_var vid vv e = c_ret_ref = e.c_ret_ref; c_ret_lbl = e.c_ret_lbl; c_save_regs = e.c_save_regs; + c_free_regs = e.c_free_regs; c_fp_used = e.c_fp_used; c_need_fp = e.c_need_fp; } +let env_get_free_reg e = + let r, more = List.hd e.c_free_regs, List.tl e.c_free_regs in + { c_penv = e.c_penv; + c_names = e.c_names; + c_ret_ref = e.c_ret_ref; + c_ret_lbl = e.c_ret_lbl; + c_need_fp = e.c_need_fp; + c_fp_used = e.c_fp_used; + c_free_regs = more; + c_save_regs = r::e.c_save_regs }, r + let globals_env = ref Smap.empty (* Chaînes de caractères utilisées dans le programme *) @@ -132,6 +148,7 @@ type expr_type = let cla r a = match a with | Addr -> nop | AddrByReg(x, rg) -> la r areg (x, rg) + | Value r -> raise (Reference_register r) | _ -> assert false let cr r a = match a with (* conditionnally read *) | Addr -> lw r areg (0, r) @@ -142,7 +159,6 @@ let crb r q a = match a with | Value k -> q, k | _ -> q ++ cr r a, r -let use_regs = [ v0; v1; t0; t1; t2; t3; t4; t5; t6; t7; t8; t9 ] let spare_reg = s0 let spare_reg2 = s1 @@ -171,6 +187,7 @@ let saver env save_regs = c_ret_lbl = env.c_ret_lbl; c_fp_used = new_fp_used; c_need_fp = env.c_need_fp; + c_free_regs = env.c_free_regs; c_save_regs = (List.filter (fun k -> k <> r) env.c_save_regs) } ) (nop, nop, env) save_regs @@ -259,7 +276,8 @@ let rec gen_expr env free_regs save_regs e = | Value r -> t, AddrByReg (0, r) | _ -> t ++ cr r a, Addr end - | Ast.Ref -> t ++ cla r a, Copy + | Ast.Ref -> + t ++ cla r a, Copy | Ast.Plus -> t ++ cr r a, Copy | Ast.Minus -> t ++ cr r a ++ neg r r, Copy | Ast.Not -> t ++ cr r a ++ not_ r r, Copy @@ -365,7 +383,7 @@ and code_for_args env arg_list regs = let args_in_stack = List.rev args_in_stack in let code_for_stack, _ = List.fold_left (fun (code, u) (arg, byref) -> - let c, addr = gen_expr kenv use_regs [] arg in + let c, addr = gen_expr kenv (v0::kenv.c_free_regs) [] arg in (if byref then c ++ cla v0 addr ++ sw v0 areg (-kenv.c_fp_used + u, fp) ++ code, u+4 else @@ -379,7 +397,7 @@ and code_for_args env arg_list regs = let rec mk_code_callz e = function | [] -> nop | (reg, (expr, byref))::more_args -> - let c, addr = gen_expr e (reg::use_regs) [] expr in + let c, addr = gen_expr e (reg::kenv.c_free_regs) [] expr in if more_args = [] then c ++ (if byref then cla reg addr else cr reg addr) else @@ -395,7 +413,7 @@ and code_for_args env arg_list regs = let code_reg_dont_call, _ = List.fold_left (fun (code, ur) (reg, (expr, byref)) -> - let c, addr = gen_expr kenv (reg::use_regs) ur expr in + let c, addr = gen_expr kenv (reg::kenv.c_free_regs) ur expr in code ++ c ++ (if byref then cla reg addr else cr reg addr), reg::ur) (nop, []) arg_reg_dont_call in @@ -403,34 +421,34 @@ and code_for_args env arg_list regs = in code, (List.map fst args_in_regs), kenv -let gen_expr_v0 env = gen_expr env use_regs env.c_save_regs - +let gen_expr_dr dr env = gen_expr env (dr::env.c_free_regs) env.c_save_regs +let gen_expr_v0 = gen_expr_dr v0 -let rec gen_stmt env = function - | TSEmpty -> nop, nop, env +let rec gen_stmt alloc_vars_in_regs env = function + | TSEmpty -> nop, env | TSExpr(e) -> - comment "expr" ++ (fst (gen_expr_v0 env e)), nop, env + comment "expr" ++ (fst (gen_expr_v0 env e)), env | TSIf(cond, s1, s2) -> let c, a = gen_expr_v0 env cond in let c, reg = crb v0 c a in let l_else = id "_cond_else" in let l_end = id "_cond_end" in - let c_then, d_then, _ = gen_stmt env s1 in - let c_else, d_else, _ = gen_stmt env s2 in + let c_then = gen_block env [s1] in + let c_else = gen_block env [s2] in comment "if" ++ c ++ beqz reg l_else ++ c_then ++ b l_end ++ label l_else ++ c_else - ++ label l_end, d_then ++ d_else, env + ++ label l_end, env | TSWhile(cond, body) -> let c, a = gen_expr_v0 env cond in let c, reg = crb v0 c a in let l_begin = id "_while_begin" in let l_cond = id "_while_cond" in - let c_body, d_body, _ = gen_stmt env body in + let c_body = gen_block env [body] in comment "while" ++ b l_cond ++ label l_begin ++ c_body - ++ label l_cond ++ c ++ bnez reg l_begin, d_body, env + ++ label l_cond ++ c ++ bnez reg l_begin, env | TSFor(before, cond, after, body) -> let l_begin = id "_for_begin" in let l_cond = id "_for_cond" in @@ -444,38 +462,44 @@ let rec gen_stmt env = function let c, a = gen_expr_v0 env x in let c, reg = crb v0 c a in c ++ bnez reg l_begin in - let c_body, d_body, _ = gen_stmt env body in + let c_body = gen_block env [body] in comment "for" ++ c_before ++ b l_cond ++ label l_begin ++ c_body ++ c_after - ++ label l_cond ++ c_cond, d_body, env + ++ label l_cond ++ c_cond, env | TSBlock(b) -> - let c, d = gen_block env b in - comment "block" ++ c, d, env + let c = gen_block env b in + comment "block" ++ c, env | TSReturn (None) -> - comment "return" ++ b env.c_ret_lbl, nop, env + comment "return" ++ b env.c_ret_lbl, env | TSReturn (Some e) -> let c, a = gen_expr_v0 env e in comment "return" ++ c ++ (if env.c_ret_ref then cla v0 a else cr v0 a) - ++ b env.c_ret_lbl, nop, env + ++ b env.c_ret_lbl, env | TSDeclare (ty, id) -> - let s = type_size env.c_penv ty in - let env2, pos = env_push s env in - let code = match ty with - | TClass(i) -> - let c = get_c env.c_penv i in - let cproto = List.find - (fun p -> p.tp_ret_type = None && p.tp_name = i && p.tp_args = []) c.tc_methods in - let code_save_regs, code_restore_regs, env_regs_saved = saver env2 env.c_save_regs in - code_save_regs - ++ la a0 areg (pos, fp) - ++ la sp areg (-env_regs_saved.c_fp_used, fp) ++ jal cproto.tp_unique_ident - ++ code_restore_regs - | _ -> sw zero areg (pos, fp) - in - comment ("declare " ^ id) ++ code, nop, - env_add_var id (VStack pos) env2 + if num ty && alloc_vars_in_regs && List.length env.c_free_regs > 5 then + (* allocate variable in register *) + let env2, reg = env_get_free_reg env in + comment ("declare " ^ id) ++ move reg zero, + env_add_var id (VRegister reg) env2 + else + let s = type_size env.c_penv ty in + let env2, pos = env_push s env in + let code = match ty with + | TClass(i) -> + let c = get_c env.c_penv i in + let cproto = List.find + (fun p -> p.tp_ret_type = None && p.tp_name = i && p.tp_args = []) c.tc_methods in + let code_save_regs, code_restore_regs, env_regs_saved = saver env2 env.c_save_regs in + code_save_regs + ++ la a0 areg (pos, fp) + ++ la sp areg (-env_regs_saved.c_fp_used, fp) ++ jal cproto.tp_unique_ident + ++ code_restore_regs + | _ -> sw zero areg (pos, fp) + in + comment ("declare " ^ id) ++ code, + env_add_var id (VStack pos) env2 | TSDeclareAssignConstructor(cls, id, constr, args) -> let env2, pos = env_push cls.tc_size env in let code = @@ -486,49 +510,63 @@ let rec gen_stmt env = function ++ la sp areg (-env_args.c_fp_used, fp) ++ jal constr ++ code_restore_regs in - comment ("declare " ^ id) ++ code, nop, + comment ("declare " ^ id) ++ code, env_add_var id (VStack pos) env2 | TSDeclareAssignExpr ((ty, ref), id, e) -> - let s = if ref then 4 else type_size env.c_penv ty in - assert (s = 4); - let env2, pos = env_push 4 env in - let code, a = gen_expr_v0 env e in - comment ("declare " ^ id) - ++ (if ref then - code ++ cla v0 a ++ sw v0 areg (pos, fp) - else - let k, b = crb v0 code a in - k ++ sw b areg (pos, fp) - ), nop, - env_add_var id (if ref then VStackByRef pos else VStack pos) env2 + assert (ref || num ty); + if alloc_vars_in_regs && List.length env.c_free_regs > 5 then + (* allocate variable in register *) + let env2, reg = env_get_free_reg env in + let code, a = gen_expr env (reg::env2.c_free_regs) env.c_save_regs e in + comment ("declare " ^ id) + ++ code ++ (if ref then cla reg a else cr reg a), + env_add_var id (if ref then VRegisterByRef reg else VRegister reg) env2 + else + let code, a = gen_expr_v0 env e in + let env2, pos = env_push 4 env in + comment ("declare " ^ id) + ++ (if ref then + code ++ cla v0 a ++ sw v0 areg (pos, fp) + else + let k, b = crb v0 code a in + k ++ sw b areg (pos, fp) + ), + env_add_var id (if ref then VStackByRef pos else VStack pos) env2 | TSWriteCout(sl) -> let save_code, restore_code, env2 = saver env (if List.mem a0 env.c_save_regs then [a0] else []) in - let text1, data1 = List.fold_left - (fun (text, data) -> function + let text1 = List.fold_left + (fun text -> function | TSEExpr(e) -> - let t, a = gen_expr env2 (a0::use_regs) (env2.c_save_regs) e in - text ++ t ++ cr a0 a ++ li v0 1 ++ syscall, data + let t, a = gen_expr_dr a0 env2 e in + text ++ t ++ cr a0 a ++ li v0 1 ++ syscall | TSEStr(s) -> - let l, d = + let l = if Hashtbl.mem strings s then - Hashtbl.find strings s, nop + Hashtbl.find strings s else let l = id "_s" in Hashtbl.add strings s l; - l, label l ++ asciiz s + l in - text ++ la a0 alab l ++ li v0 4 ++ syscall, data ++ d) - (nop, nop) sl in + text ++ la a0 alab l ++ li v0 4 ++ syscall) + nop sl in comment "cout<<..." - ++ save_code ++ text1 ++ restore_code, data1, env + ++ save_code ++ text1 ++ restore_code, env and gen_block env b = - let text, data, fin_env = - List.fold_left (fun (t, d, e) s -> - let tt, dd, ee = gen_stmt e s in - t ++ tt, d ++ dd, ee) - (nop, nop, env) b + let rec fold env = function + | [] -> nop + | stmt::next -> + let does_call_after = List.exists stmt_does_call next in + try + let tt, ee = gen_stmt (not does_call_after) env stmt in + let more_code = fold ee next in + tt ++ more_code + with Reference_register _ -> + let tt, ee = gen_stmt false env stmt in + let more_code = fold ee next in + tt ++ more_code in - text, data + fold env b let gen_decl tenv decl = match decl with | TDGlobal(ty, id) -> @@ -558,6 +596,7 @@ let gen_decl tenv decl = match decl with c_ret_lbl = "_return_" ^ proto.tp_unique_ident; c_fp_used = 8; c_need_fp = need_fp; + c_free_regs = [ t0; t1; t2; t3; t4; t5; t6; t7; t8; t9; v1 ]; c_save_regs = List.filter (fun r -> not (List.mem r free_regs)) [a0; a1; a2; a3]; } in let code_for_constructor, does_calls = match proto.tp_ret_type with @@ -575,19 +614,26 @@ let gen_decl tenv decl = match decl with let save_code, unsave_code, env2 = saver env (List.filter (fun x -> x <> a0 || proto.tp_class = None) env.c_save_regs) in - let text, data = gen_block env2 block in + let text = gen_block env2 block in label proto.tp_unique_ident ++ sw fp areg (-4, sp) ++ sw ra areg (-8, sp) ++ move fp sp ++ code_for_virtual ++ save_code ++ code_for_constructor ++ text ++ label env.c_ret_lbl ++ move sp fp ++ lw fp areg (-4, sp) ++ lw ra areg (-8, sp) - ++ jr ra, data + ++ jr ra, nop else - let text, data = gen_block env block in + let rec bb_fp e = + try + gen_block e block + with Reference_register r -> + let save_code, _, env2 = saver env [r] in + save_code ++ bb_fp env2 + in + let text = bb_fp env in label proto.tp_unique_ident ++ (if !need_fp then sw fp areg (-4, sp) ++ move fp sp else nop) ++ code_for_virtual ++ text ++ label env.c_ret_lbl ++ (if !need_fp then move sp fp ++ lw fp areg (-4, sp) else nop) - ++ jr ra, data + ++ jr ra, nop | TDClass(c) -> let constructor_calls_something = ref false in (* Call default constructor of parent classes *) @@ -667,8 +713,11 @@ let generate p = ++ li v0 10 ++ syscall ++ label "_nothing" ++ jr ra ++ text in + let str = Hashtbl.fold + (fun str lbl data -> data ++ label lbl ++ asciiz str) + strings nop in { text = text; - data = data } + data = data ++ str } with | Assert_failure (k, a, b) -> raise (Very_bad_error ( "(unexpected) Assertion failure: "^k^" at "^(string_of_int a)^":"^(string_of_int b))) |