Support impurity declarations for higher-order code.

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Branches: main

Support impurity declarations for higher-order code.

In particular, allow `impure' and `semipure' annotations on
higher-order types, higher-order calls, and lambda expresions.

NEWS:
doc/reference_manual.texi:
	Document the new language feature.

compiler/hlds_goal.m:
compiler/hlds_pred.m:
	Add `purity' field to
	- the `higher_order' alternative of the hlds_goal.generic_call type
	- the `higher_order' alternative of the hlds_pred.generic_call_id type
	- the `lambda_goal' alternative of the hlds_goal.unify_rhs type

compiler/type_util.m:
	Add a new `purity' argument to the procedures dealing with
	higher-order types.  Add code for parsing impure/semipure
	higher-order types.

compiler/lambda.m:
compiler/make_hlds.m:
compiler/typecheck.m:
compiler/post_typecheck.m:
compiler/purity.m:
compiler/polymorphism.m:
	Various minor changes to support impure/semipure higher-order lambda
	expressions.

compiler/polymorphism.m:
compiler/pseudo_type_info.m:
	XXX ought to change these to include purity in the RTTI for
	higher-order function types.

compiler/simplify.m:
	Don't try to optimize semipure/impure higher-order calls.

compiler/assertion.m:
compiler/bytecode_gen.m:
compiler/call_gen.m:
compiler/continuation_info.m:
compiler/cse_detection.m:
compiler/dead_proc_elim.m:
compiler/deep_profiling.m:
compiler/det_analysis.m:
compiler/det_util.m:
compiler/equiv_type.m:
compiler/goal_util.m:
compiler/higher_order.m:
compiler/hlds_out.m:
compiler/intermod.m:
compiler/magic.m:
compiler/magic_util.m:
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/mode_util.m:
compiler/modecheck_call.m:
compiler/modecheck_unify.m:
compiler/modes.m:
compiler/module_qual.m:
compiler/pd_util.m:
compiler/prog_rep.m:
compiler/pseudo_type_info.m:
compiler/quantification.m:
compiler/recompilation.usage.m:
compiler/rl_gen.m:
compiler/stratify.m:
compiler/switch_detection.m:
compiler/term_traversal.m:
compiler/term_util.m:
compiler/unify_gen.m:
compiler/unique_modes.m:
	Trivial changes to handle the new purity fields and/or arguments.

tests/hard_coded/purity/Mmakefile:
tests/hard_coded/purity/impure_func_t5_fixed2.m:
tests/hard_coded/purity/impure_func_t5_fixed2.exp:
tests/hard_coded/purity/impure_func_t5_fixed2.exp2:
tests/hard_coded/purity/impure_pred_t1_fixed3.m:
tests/hard_coded/purity/impure_pred_t1_fixed3.exp:
tests/invalid/purity/Mmakefile:
tests/invalid/purity/impure_func_t5_fixed.m:
tests/invalid/purity/impure_func_t5_fixed.err_exp:
tests/invalid/purity/impure_pred_t1_fixed.m:
tests/invalid/purity/impure_pred_t1_fixed.err_exp:
	Add new test cases to test the new feature.

tests/invalid/purity/impure_func_t5.err_exp:
tests/invalid/purity/impure_pred_t1.err_exp:
tests/invalid/purity/impure_pred_t2.err_exp:
tests/invalid/purity/purity.err_exp:
tests/invalid/purity/purity_nonsense.err_exp:
	Update the expected error messages for existing test cases.

tests/invalid/purity/.cvsignore:
	New file, copied from tests/invalid/.cvsignore.

compiler/lambda.m

@@ -1,5 +1,5 @@
 %-----------------------------------------------------------------------------%
-% Copyright (C) 1995-2002 The University of Melbourne.
+% Copyright (C) 1995-2003 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.
 %-----------------------------------------------------------------------------%
@@ -232,14 +232,14 @@ lambda__process_goal(Goal0 - GoalInfo0, Goal) -->
 
 lambda__process_goal_2(unify(XVar, Y, Mode, Unification, Context), GoalInfo,
 			Unify - GoalInfo) -->
-	( { Y = lambda_goal(PredOrFunc, EvalMethod, _, NonLocalVars, Vars, 
-			Modes, Det, LambdaGoal0) } ->
+	( { Y = lambda_goal(Purity, PredOrFunc, EvalMethod, _, NonLocalVars,
+			Vars, Modes, Det, LambdaGoal0) } ->
 		% first, process the lambda goal recursively, in case it
 		% contains some nested lambda expressions.
 		lambda__process_goal(LambdaGoal0, LambdaGoal1),
 
 		% then, convert the lambda expression into a new predicate
-		lambda__process_lambda(PredOrFunc, EvalMethod, Vars,
+		lambda__process_lambda(Purity, PredOrFunc, EvalMethod, Vars,
 			Modes, Det, NonLocalVars, LambdaGoal1, 
 			Unification, Y1, Unification1),
 		{ Unify = unify(XVar, Y1, Mode, Unification1, Context) }
@@ -303,14 +303,14 @@ lambda__process_cases([case(ConsId, Goal0) | Cases0],
 	lambda__process_goal(Goal0, Goal),
 	lambda__process_cases(Cases0, Cases).
 
-:- pred lambda__process_lambda(pred_or_func, lambda_eval_method,
+:- pred lambda__process_lambda(purity, pred_or_func, lambda_eval_method,
 		list(prog_var), list(mode), determinism, list(prog_var),
 		hlds_goal, unification, unify_rhs, unification,
 		lambda_info, lambda_info).
-:- mode lambda__process_lambda(in, in, in, in, in, in, in, in, out, out,
+:- mode lambda__process_lambda(in, in, in, in, in, in, in, in, in, out, out,
 		in, out) is det.
 
-lambda__process_lambda(PredOrFunc, EvalMethod, Vars, Modes, Detism,
+lambda__process_lambda(Purity, PredOrFunc, EvalMethod, Vars, Modes, Detism,
 		OrigNonLocals0, LambdaGoal, Unification0, Functor,
 		Unification, LambdaInfo0, LambdaInfo) :-
 	LambdaInfo0 = lambda_info(VarSet, VarTypes, _PredConstraints, TVarSet,
@@ -501,6 +501,7 @@ lambda__process_lambda(PredOrFunc, EvalMethod, Vars, Modes, Detism,
 		list__append(ArgModes1, Modes, AllArgModes),
 		map__apply_to_list(AllArgVars, VarTypes, ArgTypes),
 
+		purity_to_markers(Purity, LambdaMarkers0),
 		( 
 			% Pass through the aditi markers for 
 			% aggregate query closures.
@@ -530,18 +531,20 @@ lambda__process_lambda(PredOrFunc, EvalMethod, Vars, Modes, Detism,
 				; Marker = aditi_no_memo
 				)),
 				MarkerList0, MarkerList),
-			marker_list_to_markers(MarkerList, LambdaMarkers)
+			LambdaMarkers = list__foldl((func(LMs0, Mrk) = LMs :-
+				add_marker(Mrk, LMs0, LMs)),
+				MarkerList, LambdaMarkers0)
 		;
 			EvalMethod = (aditi_bottom_up)
 		->
-			marker_list_to_markers([aditi], LambdaMarkers)
+			add_marker(LambdaMarkers0, aditi, LambdaMarkers)
 		;
 			EvalMethod = (aditi_top_down)
 		->
-			marker_list_to_markers([(aditi_top_down)],
+			add_marker(LambdaMarkers0, aditi_top_down,
 				LambdaMarkers)
 		; 
-			init_markers(LambdaMarkers)
+			LambdaMarkers = LambdaMarkers0
 		),
 
 		% Now construct the proc_info and pred_info for the new
@@ -562,7 +565,7 @@ lambda__process_lambda(PredOrFunc, EvalMethod, Vars, Modes, Detism,
 		set__init(Assertions),
 
 		pred_info_create(ModuleName, PredName, TVarSet, ExistQVars,
-			ArgTypes, true, LambdaContext, local, LambdaMarkers,
+			ArgTypes, true, LambdaContext, local, LambdaMarkers,  
 			PredOrFunc, Constraints, Owner, Assertions, ProcInfo,
 			ProcId, PredInfo),