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|
-- This file is part of SmartEiffel The GNU Eiffel Compiler Tools and Libraries
--
-- SmartEiffel is free software; you can redistribute it and/or modify it
-- under the terms of the GNU General Public License, as published by the
-- Free Software Foundation; either version 2, or (at your option) any later
-- version.
-- SmartEiffel is distributed in the hope that it will be useful but WITHOUT
-- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
-- FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
-- more details. You should have received a copy of the GNU General Public
-- License along with SmartEiffel; see the file COPYING. If not, write to
-- the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
-- MA 02111-1307, USA.
--
-- Copyright(C) 1994-2002: INRIA - LORIA (INRIA Lorraine) - ESIAL U.H.P.
-- - University of Nancy 1 - FRANCE
-- Copyright(C) 2003: INRIA - LORIA (INRIA Lorraine) - I.U.T. Charlemagne
-- - University of Nancy 2 - FRANCE
--
-- Dominique COLNET, Suzanne COLLIN, Olivier ZENDRA,
-- Philippe RIBET, Cyril ADRIAN
--
-- http://SmartEiffel.loria.fr - SmartEiffel@loria.fr
--
class E_LOOP
--
-- The Eiffel instruction : "from ... until ... loop ... end".
--
inherit INSTRUCTION
creation make
feature
start_position: POSITION
-- Of letter 'f' of "from".
initialize: COMPOUND
invariant_clause: LOOP_INVARIANT
variant_clause: LOOP_VARIANT
until_expression: EXPRESSION
loop_body: COMPOUND
side_effect_free: BOOLEAN is False
once_pre_computable: BOOLEAN is False
end_mark_comment: BOOLEAN is True
afd_check is
do
if loop_check then
if variant_clause /= Void then
variant_clause.afd_check
end
if invariant_clause /= Void then
invariant_clause.afd_check
end
end
if initialize /= Void then
initialize.afd_check
end
until_expression.afd_check
if loop_body /= Void then
loop_body.afd_check
end
end
safety_check is
do
if initialize /= Void then
initialize.safety_check
end
until_expression.safety_check
if loop_body /= Void then
loop_body.safety_check
end
end
simplify_2(container: COMPOUND; index: INTEGER) is
local
bc: BOOLEAN_CONSTANT
do
if initialize /= Void then
initialize := initialize.simplify_2
end
until_expression := until_expression.simplify_2
bc ?= until_expression
if loop_body /= Void then
loop_body := loop_body.simplify_2
end
if bc /= Void and then bc.value and then initialize = Void then
container.remove(index)
end
end
collect_c_tmp is
do
end
compile_to_c is
local
need_se_tmp, variant_flag, invariant_flag: BOOLEAN
do
if loop_check and then variant_clause /= Void then
cpp.put_string(once "{int c=0;int v=0;%N")
variant_flag := True
end
if initialize /= Void then
initialize.compile_to_c
end
if loop_check and then invariant_clause /= Void then
invariant_clause.compile_to_c
invariant_flag := True
end
until_expression.collect_c_tmp
need_se_tmp := cpp.se_tmp_open_declaration
cpp.put_string(once "while (!(")
if ace.no_check then
cpp.trace_boolean_expression(until_expression)
else
until_expression.compile_to_c
end
cpp.put_string(once "))%N{%N")
if variant_flag then
cpp.variant_check(variant_clause.expression)
end
if loop_body /= Void then
loop_body.compile_to_c
end
if invariant_flag then
invariant_clause.compile_to_c
end
cpp.put_string(once "}%N")
if need_se_tmp then
cpp.se_tmp_close_declaration
end
if variant_flag then
cpp.put_string(fz_12)
end
end
compile_to_jvm is
local
until_point, exit_point: INTEGER
ca: like code_attribute
counter, previous: INTEGER
do
ca := code_attribute
if loop_check then
counter := ca.extra_local_size1
ca.opcode_iconst_0
ca.opcode_istore(counter)
previous := ca.extra_local_size1
ca.opcode_iconst_0
ca.opcode_istore(previous)
end
if initialize /= Void then
initialize.compile_to_jvm
end
if loop_check then
if invariant_clause /= Void then
invariant_clause.compile_to_jvm(True)
ca.opcode_pop
end
end
until_point := ca.program_counter
exit_point := until_expression.jvm_branch_if_true
if loop_check then
if variant_clause /= Void then
ca.opcode_iload(counter)
ca.opcode_iload(previous)
ca.runtime_check_loop_variant(variant_clause.expression)
ca.opcode_istore(previous)
end
end
if loop_body /= Void then
loop_body.compile_to_jvm
end
if loop_check then
if invariant_clause /= Void then
invariant_clause.compile_to_jvm(True)
ca.opcode_pop
end
end
if loop_check then
ca.opcode_iinc(counter,1)
end
ca.opcode_goto_backward(until_point)
ca.resolve_u2_branch(exit_point)
end
use_current: BOOLEAN is
do
if loop_check and then variant_clause /= Void then
Result := Result or else variant_clause.use_current
end
if initialize /= Void then
Result := Result or else initialize.use_current
end
Result := Result or else until_expression.use_current
if loop_check and then invariant_clause /= Void then
Result := Result or else invariant_clause.use_current
end
if loop_body /= Void then
Result := Result or else loop_body.use_current
end
end
stupid_switch(run_time_set: RUN_TIME_SET): BOOLEAN is
do
Result :=
(initialize = Void or else initialize.stupid_switch(run_time_set))
and then
until_expression.stupid_switch(run_time_set)
and then
(loop_body = Void or else loop_body.stupid_switch(run_time_set))
end
to_runnable(ct: E_TYPE): like Current is
local
ue: like until_expression
do
if current_type = Void then
current_type := ct
loop_check := ct.base_class.loop_check
if initialize /= Void then
initialize := initialize.to_runnable(ct)
if initialize = Void then
error(start_position,"Bad initialisation part.")
end
end
if loop_check and then invariant_clause /= Void then
invariant_clause := invariant_clause.to_runnable(ct)
if invariant_clause = Void then
error(start_position,"Bad invariant.")
end
end
if loop_check and then variant_clause /= Void then
variant_clause := variant_clause.to_runnable(ct)
if variant_clause = Void then
error(start_position,"Bad variant for this loop.")
end
end
ue := until_expression.to_runnable(ct)
if ue /= Void then
if not ue.result_type.is_boolean then
error(ue.start_position,
"Expression of until must be BOOLEAN.")
error_handler.add_type(ue.result_type,fz_is_not_boolean)
error_handler.print_as_error
end
until_expression := ue
else
error(start_position, "This loop has an invalid expression.")
end
if loop_body /= Void then
loop_body := loop_body.to_runnable(ct)
if loop_body = Void then
error(start_position,"Invalid loop body.")
end
end
if nb_errors = 0 then
Result := Current
end
else
!!Result.make(start_position,initialize,invariant_clause,
variant_clause,until_expression,loop_body)
Result := Result.to_runnable(ct)
end
end
pretty_print is
local
semi_colon_flag: BOOLEAN
do
pretty_printer.indent
pretty_printer.keyword(fz_from)
if initialize /= Void then
initialize.pretty_print
end
if invariant_clause /= Void then
invariant_clause.pretty_print
end
if variant_clause /= Void then
pretty_printer.indent
pretty_printer.keyword(fz_variant)
pretty_printer.indent_level_increment
semi_colon_flag := pretty_printer.semi_colon_flag
pretty_printer.set_semi_colon_flag(False)
variant_clause.pretty_print
pretty_printer.set_semi_colon_flag(semi_colon_flag)
pretty_printer.indent_level_decrement
end
pretty_printer.indent
pretty_printer.keyword(fz_until)
pretty_printer.indent_level_increment
pretty_printer.indent
pretty_printer.set_semi_colon_flag(False)
until_expression.pretty_print
pretty_printer.indent_level_decrement
pretty_printer.indent
pretty_printer.keyword(fz_loop)
pretty_printer.indent
if loop_body /= Void then
loop_body.pretty_print
end
pretty_printer.indent
pretty_printer.keyword(fz_end)
if pretty_printer.print_end_of_statement then
pretty_printer.put_end_of(fz_loop)
end
end
feature {COMPOUND,INSTRUCTION_WITH_COMMENT}
verify_scoop(allowed: FORMAL_ARG_LIST) is
local
dummy: BOOLEAN
do
if initialize /= Void then
initialize.verify_scoop(allowed)
end
if invariant_clause /= Void then
invariant_clause.verify_scoop(allowed)
end
if variant_clause /= Void then
variant_clause.verify_scoop(allowed)
end
dummy := until_expression.verify_scoop(allowed)
if loop_body /= Void then
loop_body.verify_scoop(allowed)
end
end
feature {E_LOOP_VISITOR}
accept(visitor: E_LOOP_VISITOR) is
do
visitor.visit_e_loop(Current)
end
feature {NONE}
current_type: E_TYPE
loop_check: BOOLEAN
make(sp: like start_position
i: like initialize
ic : like invariant_clause
vc: like variant_clause
ue : like until_expression
lb : like loop_body) is
require
not sp.is_unknown
ue /= Void
do
start_position := sp
initialize := i
invariant_clause := ic
variant_clause := vc
until_expression := ue
loop_body := lb
ensure
start_position = sp
initialize = i
invariant_clause = ic
variant_clause = vc
until_expression = ue
loop_body = lb
end
invariant
not start_position.is_unknown
until_expression /= Void
end -- E_LOOP
|
