during fusion, mark unused producer (PR_Unsed) expressions and variables with...

during fusion, mark unused producer (PR_Unsed) expressions and variables with VI_NotUsed and ExprToBeRemoved

frontend/classify.icl

@@ -493,6 +493,8 @@ instance consumerRequirements Expression where
 				= init_variables dictionaries (inc ai_next_var) (inc ai_next_var_of_fun) ai_var_heap
 			init_variables [] ai_next_var ai_next_var_of_fun ai_var_heap
 				= (ai_next_var,ai_next_var_of_fun,ai_var_heap)
+	consumerRequirements ExprToBeRemoved _ ai
+		= (CPassive, False, ai)
 	consumerRequirements expr _ ai
 		= abort ("consumerRequirements [Expression]" ---> expr)
 
@@ -1490,6 +1492,8 @@ count_locals (DictionariesFunction dictionaries expr expr_type) n
 			| fv_count > 0
 				= n+1
 				= n
+count_locals ExprToBeRemoved n
+	= n
 
 count_optional_locals (Yes e) n
 	= count_locals e n

frontend/partition.icl

@@ -161,6 +161,12 @@ where
 						# (mark, fun_defs, pi) = partitionate_function fc_index max_fun_nr fun_defs pi
 						= visit_functions funs (min min_dep mark) max_fun_nr fun_defs pi
 						= visit_functions funs (min min_dep mark) max_fun_nr fun_defs pi
+				visit_functions [GeneratedFunCall fc_index _:funs] min_dep max_fun_nr fun_defs pi=:{pi_marks`}
+					#! mark = pi_marks`.[fc_index]
+					| mark == NotChecked
+						# (mark, fun_defs, pi) = partitionate_function fc_index max_fun_nr fun_defs pi
+						= visit_functions funs (min min_dep mark) max_fun_nr fun_defs pi
+						= visit_functions funs (min min_dep mark) max_fun_nr fun_defs pi
 				visit_functions [DclFunCall module_index fc_index:funs] min_dep max_fun_nr fun_defs pi
 					= visit_functions funs min_dep max_fun_nr fun_defs pi
 				visit_functions [] min_dep max_fun_nr fun_defs pi
@@ -439,6 +445,8 @@ where
 		= fc_state
 	find_calls fc_info (DictionariesFunction dictionaries expr expr_type) fc_state
 		= find_calls fc_info expr fc_state
+	find_calls fc_info ExprToBeRemoved fc_state
+		= fc_state
 
 instance find_calls App
 where

frontend/syntax.dcl

@@ -1413,6 +1413,7 @@ cIsNotStrict	:== False
 				| EE
 				| NoBind ExprInfoPtr /* auxiliary, to store fields that are not specified in a record expression */ 
 				| FailExpr !Ident // only allowed on (case) root positions
+				| ExprToBeRemoved
 
 ::	CodeBinding	variable :== Env String variable
 

frontend/syntax.icl

@@ -410,6 +410,7 @@ where
 	(<<<) file (TypeSignature array_kind expr) = file <<< "TypeSignature " <<< '(' <<< expr <<< ')'
 	(<<<) file (DictionariesFunction dictionaries expr expr_type)
 		= file <<< "DictionariesFunction " <<< dictionaries <<< expr <<< expr_type
+	(<<<) file ExprToBeRemoved = file <<< "** ExprToBeRemoved **"
 	(<<<) file expr         				= abort ("<<< (Expression)" )
 	
 instance <<< LetBind

frontend/trans.icl

@@ -2101,9 +2101,10 @@ determine_arg PR_Empty _ form=:{fv_ident,fv_info_ptr} _ ((linear_bit,cons_arg),
 			, das_new_cons_args		= [cons_arg : das.das_new_cons_args]
 			, das_var_heap			= das_var_heap }
 
-determine_arg PR_Unused _ form prod_index (_,ro) das
+determine_arg PR_Unused _ {fv_info_ptr} prod_index (_,ro) das=:{das_var_heap}
+	# das_var_heap = writeVarInfo fv_info_ptr VI_NotUsed das_var_heap
 	# no_arg_type = {ats_types = [], ats_strictness = NotStrict}
-	= {das & das_arg_types.[prod_index] = no_arg_type}
+	= {das & das_arg_types.[prod_index] = no_arg_type, das_var_heap=das_var_heap}
 
 determine_arg (PR_Class class_app free_vars_and_types class_type) _ {fv_info_ptr} prod_index (_,ro)
 			  das=:{das_arg_types, das_subst, das_type_heaps, das_predef}
@@ -4520,6 +4521,8 @@ where
 				-> writeVarInfo var_info_ptr VI_Empty var_heap
 			VI_Body _ _ _ _ _
 				-> writeVarInfo var_info_ptr VI_Empty var_heap
+			VI_NotUsed
+				-> var_heap
 
 instance clearVariables Expression
 where
@@ -5078,6 +5081,8 @@ copyVariable var=:{var_info_ptr} ci cs
 			-> copy_dictionary_variable app_symb app_args class_type ci cs
 		VI_ExpressionOrBody expr _ _ _ _ _
 			-> (expr, cs)
+		VI_NotUsed
+			-> (ExprToBeRemoved, cs)
 		_
 			-> (Var var, cs)