%-----------------------------------------------------------------------------% % vim: ft=mercury ts=4 sw=4 et %-----------------------------------------------------------------------------% % Copyright (C) 1994-2009 The University of Melbourne. % This file may only be copied under the terms of the GNU General % Public License - see the file COPYING in the Mercury distribution. %-----------------------------------------------------------------------------% % % File: code_util.m. % % Various utilities routines for code generation and recognition of builtins. % %-----------------------------------------------------------------------------% :- module ll_backend.code_util. :- interface. :- import_module hlds.hlds_goal. :- import_module hlds.hlds_llds. :- import_module hlds.hlds_module. :- import_module hlds.hlds_pred. :- import_module hlds.hlds_rtti. :- import_module ll_backend.llds. :- import_module mdbcomp.prim_data. :- import_module parse_tree.prog_data. :- import_module assoc_list. :- import_module bool. :- import_module list. :- import_module maybe. :- import_module pair. %-----------------------------------------------------------------------------% % Create a code address which holds the address of the specified procedure. % The `immed' argument should be `no' if the the caller wants the returned % address to be valid from everywhere in the program. If being valid from % within the current procedure is enough, this argument should be `yes' % wrapped around the value of the --procs-per-c-function option and the % current procedure id. Using an address that is only valid from within % the current procedure may make jumps more efficient. % :- type immed == maybe(pair(int, pred_proc_id)). :- func make_entry_label(module_info, pred_id, proc_id, immed) = code_addr. :- func make_entry_label_from_rtti(rtti_proc_label, immed) = code_addr. % Create a label which holds the address of the specified procedure, % which must be defined in the current module (procedures that are % imported from other modules have representations only as code_addrs, % not as labels, since their address is not known at C compilation time). % The fourth argument has the same meaning as for make_entry_label. % :- func make_local_entry_label(module_info, pred_id, proc_id, immed) = label. % Create a label internal to a Mercury procedure. % :- func make_internal_label(module_info, pred_id, proc_id, int) = label. :- func extract_proc_label_from_code_addr(code_addr) = proc_label. :- pred arg_loc_to_register(arg_loc::in, lval::out) is det. :- pred max_mentioned_reg(list(lval)::in, int::out) is det. :- pred max_mentioned_abs_reg(list(abs_locn)::in, int::out) is det. :- pred goal_may_alloc_temp_frame(hlds_goal::in, bool::out) is det. % Negate a condition. % This is used mostly just to make the generated code more readable. % :- pred neg_rval(rval::in, rval::out) is det. :- pred negate_the_test(list(instruction)::in, list(instruction)::out) is det. % These predicates return the set of lvals referenced in an rval % and an lval respectively. Lvals referenced indirectly through % lvals of the form var(_) are not counted. % :- func lvals_in_rval(rval) = list(lval). :- func lvals_in_lval(lval) = list(lval). :- func lvals_in_lvals(list(lval)) = list(lval). % Given a procedure that already has its arg_info field filled in, % return a list giving its input variables and their initial locations. % :- pred build_input_arg_list(proc_info::in, assoc_list(prog_var, lval)::out) is det. %---------------------------------------------------------------------------% %---------------------------------------------------------------------------% :- implementation. :- import_module backend_libs.builtin_ops. :- import_module backend_libs.proc_label. :- import_module backend_libs.rtti. :- import_module hlds.code_model. :- import_module libs.compiler_util. :- import_module int. :- import_module term. %---------------------------------------------------------------------------% make_entry_label(ModuleInfo, PredId, ProcId, Immed) = ProcAddr :- RttiProcLabel = make_rtti_proc_label(ModuleInfo, PredId, ProcId), ProcAddr = make_entry_label_from_rtti(RttiProcLabel, Immed). make_entry_label_from_rtti(RttiProcLabel, Immed) = ProcAddr :- ProcIsImported = RttiProcLabel ^ rpl_proc_is_imported, ( ProcIsImported = yes, ProcLabel = make_proc_label_from_rtti(RttiProcLabel), ProcAddr = code_imported_proc(ProcLabel) ; ProcIsImported = no, Label = make_local_entry_label_from_rtti(RttiProcLabel, Immed), ProcAddr = code_label(Label) ). make_local_entry_label(ModuleInfo, PredId, ProcId, Immed) = Label :- RttiProcLabel = make_rtti_proc_label(ModuleInfo, PredId, ProcId), Label = make_local_entry_label_from_rtti(RttiProcLabel, Immed). :- func make_local_entry_label_from_rtti(rtti_proc_label, immed) = label. make_local_entry_label_from_rtti(RttiProcLabel, Immed) = Label :- ProcLabel = make_proc_label_from_rtti(RttiProcLabel), ( Immed = no, % If we want to define the label or use it to put it into a data % structure, a label that is usable only within the current C module % won't do. ProcIsExported = RttiProcLabel ^ rpl_proc_is_exported, ( ProcIsExported = yes, EntryType = entry_label_exported ; ProcIsExported = no, EntryType = entry_label_local ), Label = entry_label(EntryType, ProcLabel) ; Immed = yes(ProcsPerFunc - proc(CurPredId, CurProcId)), Label = choose_local_label_type(ProcsPerFunc, CurPredId, CurProcId, RttiProcLabel ^ rpl_pred_id, RttiProcLabel ^ rpl_proc_id, ProcLabel) ). :- func choose_local_label_type(int, pred_id, proc_id, pred_id, proc_id, proc_label) = label. choose_local_label_type(ProcsPerFunc, CurPredId, CurProcId, PredId, ProcId, ProcLabel) = Label :- ( % If we want to branch to the label now, we prefer a form that is % usable only within the current C module, since it is likely to be % faster. ( ProcsPerFunc = 0 ; PredId = CurPredId, ProcId = CurProcId ) -> EntryType = entry_label_c_local ; EntryType = entry_label_local ), Label = entry_label(EntryType, ProcLabel). %-----------------------------------------------------------------------------% make_internal_label(ModuleInfo, PredId, ProcId, LabelNum) = Label :- ProcLabel = make_proc_label(ModuleInfo, PredId, ProcId), Label = internal_label(LabelNum, ProcLabel). extract_proc_label_from_code_addr(CodeAddr) = ProcLabel :- ( CodeAddr = code_label(Label) -> ProcLabel = get_proc_label(Label) ; CodeAddr = code_imported_proc(ProcLabelPrime) -> ProcLabel = ProcLabelPrime ; unexpected(this_file, "extract_label_from_code_addr failed") ). %-----------------------------------------------------------------------------% arg_loc_to_register(ArgLoc, reg(reg_r, ArgLoc)). %-----------------------------------------------------------------------------% max_mentioned_reg(Lvals, MaxRegNum) :- max_mentioned_reg_2(Lvals, 0, MaxRegNum). :- pred max_mentioned_reg_2(list(lval)::in, int::in, int::out) is det. max_mentioned_reg_2([], !MaxRegNum). max_mentioned_reg_2([Lval | Lvals], !MaxRegNum) :- ( Lval = reg(reg_r, N) -> int.max(N, !MaxRegNum) ; true ), max_mentioned_reg_2(Lvals, !MaxRegNum). max_mentioned_abs_reg(Lvals, MaxRegNum) :- max_mentioned_abs_reg_2(Lvals, 0, MaxRegNum). :- pred max_mentioned_abs_reg_2(list(abs_locn)::in, int::in, int::out) is det. max_mentioned_abs_reg_2([], !MaxRegNum). max_mentioned_abs_reg_2([Lval | Lvals], !MaxRegNum) :- ( Lval = abs_reg(N) -> int.max(N, !MaxRegNum) ; true ), max_mentioned_abs_reg_2(Lvals, !MaxRegNum). %-----------------------------------------------------------------------------% goal_may_alloc_temp_frame(hlds_goal(GoalExpr, _GoalInfo), May) :- goal_may_alloc_temp_frame_2(GoalExpr, May). :- pred goal_may_alloc_temp_frame_2(hlds_goal_expr::in, bool::out) is det. goal_may_alloc_temp_frame_2(generic_call(_, _, _, _), no). goal_may_alloc_temp_frame_2(plain_call(_, _, _, _, _, _), no). goal_may_alloc_temp_frame_2(unify(_, _, _, _, _), no). % We cannot safely say that a foreign code fragment does not allocate % temporary nondet frames without knowing all the #defined macros % that expand to mktempframe and variants thereof. The performance % impact of being too conservative is probably not too bad. goal_may_alloc_temp_frame_2(call_foreign_proc(_, _, _, _, _, _, _), yes). goal_may_alloc_temp_frame_2(scope(_, Goal), May) :- Goal = hlds_goal(_, GoalInfo), CodeModel = goal_info_get_code_model(GoalInfo), ( CodeModel = model_non, May = yes ; ( CodeModel = model_det ; CodeModel = model_semi ), goal_may_alloc_temp_frame(Goal, May) ). goal_may_alloc_temp_frame_2(negation(Goal), May) :- goal_may_alloc_temp_frame(Goal, May). goal_may_alloc_temp_frame_2(conj(_ConjType, Goals), May) :- goal_list_may_alloc_temp_frame(Goals, May). goal_may_alloc_temp_frame_2(disj(Goals), May) :- goal_list_may_alloc_temp_frame(Goals, May). goal_may_alloc_temp_frame_2(switch(_Var, _Det, Cases), May) :- cases_may_alloc_temp_frame(Cases, May). goal_may_alloc_temp_frame_2(if_then_else(_Vars, C, T, E), May) :- ( goal_may_alloc_temp_frame(C, yes) -> May = yes ; goal_may_alloc_temp_frame(T, yes) -> May = yes ; goal_may_alloc_temp_frame(E, May) ). goal_may_alloc_temp_frame_2(shorthand(_), _) :- % These should have been expanded out by now. unexpected(this_file, "goal_may_alloc_temp_frame_2: shorthand"). :- pred goal_list_may_alloc_temp_frame(list(hlds_goal)::in, bool::out) is det. goal_list_may_alloc_temp_frame([], no). goal_list_may_alloc_temp_frame([Goal | Goals], May) :- ( goal_may_alloc_temp_frame(Goal, yes) -> May = yes ; goal_list_may_alloc_temp_frame(Goals, May) ). :- pred cases_may_alloc_temp_frame(list(case)::in, bool::out) is det. cases_may_alloc_temp_frame([], no). cases_may_alloc_temp_frame([case(_, _, Goal) | Cases], May) :- ( goal_may_alloc_temp_frame(Goal, yes) -> May = yes ; cases_may_alloc_temp_frame(Cases, May) ). %-----------------------------------------------------------------------------% neg_rval(Rval, NegRval) :- ( neg_rval_2(Rval, NegRval0) -> NegRval = NegRval0 ; NegRval = unop(logical_not, Rval) ). :- pred neg_rval_2(rval::in, rval::out) is semidet. neg_rval_2(const(Const), const(NegConst)) :- ( Const = llconst_true, NegConst = llconst_false ; Const = llconst_false, NegConst = llconst_true ). neg_rval_2(unop(logical_not, Rval), Rval). neg_rval_2(binop(Op, X, Y), binop(NegOp, X, Y)) :- neg_op(Op, NegOp). :- pred neg_op(binary_op::in, binary_op::out) is semidet. neg_op(eq, ne). neg_op(ne, eq). neg_op(int_lt, int_ge). neg_op(int_le, int_gt). neg_op(int_gt, int_le). neg_op(int_ge, int_lt). neg_op(str_eq, str_ne). neg_op(str_ne, str_eq). neg_op(str_lt, str_ge). neg_op(str_le, str_gt). neg_op(str_gt, str_le). neg_op(str_ge, str_lt). neg_op(float_eq, float_ne). neg_op(float_ne, float_eq). neg_op(float_lt, float_ge). neg_op(float_le, float_gt). neg_op(float_gt, float_le). neg_op(float_ge, float_lt). negate_the_test([], _) :- unexpected(this_file, "negate_the_test on empty list"). negate_the_test([Instr0 | Instrs0], Instrs) :- ( Instr0 = llds_instr(if_val(Test, Target), Comment) -> neg_rval(Test, NewTest), Instrs = [llds_instr(if_val(NewTest, Target), Comment)] ; negate_the_test(Instrs0, Instrs1), Instrs = [Instr0 | Instrs1] ). %-----------------------------------------------------------------------------% lvals_in_lvals([]) = []. lvals_in_lvals([First | Rest]) = FirstLvals ++ RestLvals :- FirstLvals = lvals_in_lval(First), RestLvals = lvals_in_lvals(Rest). lvals_in_rval(lval(Lval)) = [Lval | lvals_in_lval(Lval)]. lvals_in_rval(var(_)) = []. lvals_in_rval(mkword(_, Rval)) = lvals_in_rval(Rval). lvals_in_rval(const(_)) = []. lvals_in_rval(unop(_, Rval)) = lvals_in_rval(Rval). lvals_in_rval(binop(_, Rval1, Rval2)) = lvals_in_rval(Rval1) ++ lvals_in_rval(Rval2). lvals_in_rval(mem_addr(MemRef)) = lvals_in_mem_ref(MemRef). lvals_in_lval(reg(_, _)) = []. lvals_in_lval(stackvar(_)) = []. lvals_in_lval(parent_stackvar(_)) = []. lvals_in_lval(framevar(_)) = []. lvals_in_lval(succip) = []. lvals_in_lval(maxfr) = []. lvals_in_lval(curfr) = []. lvals_in_lval(succip_slot(Rval)) = lvals_in_rval(Rval). lvals_in_lval(redofr_slot(Rval)) = lvals_in_rval(Rval). lvals_in_lval(redoip_slot(Rval)) = lvals_in_rval(Rval). lvals_in_lval(succfr_slot(Rval)) = lvals_in_rval(Rval). lvals_in_lval(prevfr_slot(Rval)) = lvals_in_rval(Rval). lvals_in_lval(hp) = []. lvals_in_lval(sp) = []. lvals_in_lval(parent_sp) = []. lvals_in_lval(field(_, Rval1, Rval2)) = lvals_in_rval(Rval1) ++ lvals_in_rval(Rval2). lvals_in_lval(lvar(_)) = []. lvals_in_lval(temp(_, _)) = []. lvals_in_lval(mem_ref(Rval)) = lvals_in_rval(Rval). lvals_in_lval(global_var_ref(_)) = []. :- func lvals_in_mem_ref(mem_ref) = list(lval). lvals_in_mem_ref(stackvar_ref(Rval)) = lvals_in_rval(Rval). lvals_in_mem_ref(framevar_ref(Rval)) = lvals_in_rval(Rval). lvals_in_mem_ref(heap_ref(Rval1, _, Rval2)) = lvals_in_rval(Rval1) ++ lvals_in_rval(Rval2). %-----------------------------------------------------------------------------% build_input_arg_list(ProcInfo, VarLvals) :- proc_info_get_headvars(ProcInfo, HeadVars), proc_info_arg_info(ProcInfo, ArgInfos), assoc_list.from_corresponding_lists(HeadVars, ArgInfos, VarArgInfos), build_input_arg_list_2(VarArgInfos, VarLvals). :- pred build_input_arg_list_2(assoc_list(prog_var, arg_info)::in, assoc_list(prog_var, lval)::out) is det. build_input_arg_list_2([], []). build_input_arg_list_2([V - Arg | Rest0], VarArgs) :- Arg = arg_info(Loc, Mode), ( Mode = top_in, arg_loc_to_register(Loc, Reg), VarArgs = [V - Reg | VarArgs0] ; ( Mode = top_out ; Mode = top_unused ), VarArgs = VarArgs0 ), build_input_arg_list_2(Rest0, VarArgs0). %---------------------------------------------------------------------------% :- func this_file = string. this_file = "code_util.m". %-----------------------------------------------------------------------------% :- end_module code_util. %-----------------------------------------------------------------------------%