From 5859d7056c951e56e3db760202801135784b4e5c Mon Sep 17 00:00:00 2001 From: Kartik Agaram Date: Sat, 16 Jun 2018 09:22:47 -0700 Subject: 4259 --- 029call_return.cc | 177 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 177 insertions(+) create mode 100644 029call_return.cc (limited to '029call_return.cc') diff --git a/029call_return.cc b/029call_return.cc new file mode 100644 index 00000000..c8c1bca6 --- /dev/null +++ b/029call_return.cc @@ -0,0 +1,177 @@ +//: Calls can also generate products, using 'reply' or 'return'. + +:(scenario return) +def main [ + 1:num, 2:num <- f 34 +] +def f [ + 12:num <- next-ingredient + 13:num <- add 1, 12:num + return 12:num, 13:num +] ++mem: storing 34 in location 1 ++mem: storing 35 in location 2 + +:(scenario reply) +def main [ + 1:num, 2:num <- f 34 +] +def f [ + 12:num <- next-ingredient + 13:num <- add 1, 12:num + reply 12:num, 13:num +] ++mem: storing 34 in location 1 ++mem: storing 35 in location 2 + +:(before "End Primitive Recipe Declarations") +RETURN, +:(before "End Primitive Recipe Numbers") +put(Recipe_ordinal, "return", RETURN); +put(Recipe_ordinal, "reply", RETURN); // synonym while teaching +put(Recipe_ordinal, "output", RETURN); // experiment +:(before "End Primitive Recipe Checks") +case RETURN: { + break; // checks will be performed by a transform below +} +:(before "End Primitive Recipe Implementations") +case RETURN: { + // Begin Return + if (Trace_stream) { + trace("trace") << current_instruction().name << ": decrementing callstack depth from " << Trace_stream->callstack_depth << end(); + --Trace_stream->callstack_depth; + if (Trace_stream->callstack_depth < 0) { + Current_routine->calls.clear(); + goto stop_running_current_routine; + } + } + Current_routine->calls.pop_front(); + // just in case 'main' returns a value, drop it for now + if (Current_routine->calls.empty()) goto stop_running_current_routine; + for (int i = 0; i < SIZE(ingredients); ++i) + trace(9998, "run") << "result " << i << " is " << to_string(ingredients.at(i)) << end(); + // make return products available to caller + copy(ingredients.begin(), ingredients.end(), inserter(products, products.begin())); + // End Return + break; // continue to process rest of *caller* instruction +} + +//: Types in return instructions are checked ahead of time. + +:(before "End Checks") +Transform.push_back(check_types_of_return_instructions); // idempotent +:(code) +void check_types_of_return_instructions(const recipe_ordinal r) { + const recipe& caller = get(Recipe, r); + trace(9991, "transform") << "--- check types of return instructions in recipe " << caller.name << end(); + for (int i = 0; i < SIZE(caller.steps); ++i) { + const instruction& caller_instruction = caller.steps.at(i); + if (caller_instruction.is_label) continue; + if (caller_instruction.products.empty()) continue; + if (is_primitive(caller_instruction.operation)) continue; + const recipe& callee = get(Recipe, caller_instruction.operation); + for (int i = 0; i < SIZE(callee.steps); ++i) { + const instruction& return_inst = callee.steps.at(i); + if (return_inst.operation != RETURN) continue; + // check types with the caller + if (SIZE(caller_instruction.products) > SIZE(return_inst.ingredients)) { + raise << maybe(caller.name) << "too few values returned from " << callee.name << '\n' << end(); + break; + } + for (int i = 0; i < SIZE(caller_instruction.products); ++i) { + reagent/*copy*/ lhs = return_inst.ingredients.at(i); + reagent/*copy*/ rhs = caller_instruction.products.at(i); + // End Check RETURN Copy(lhs, rhs) + if (!types_coercible(rhs, lhs)) { + raise << maybe(callee.name) << return_inst.name << " ingredient '" << lhs.original_string << "' can't be saved in '" << rhs.original_string << "'\n" << end(); + raise << " ['" << to_string(lhs.type) << "' vs '" << to_string(rhs.type) << "']\n" << end(); + goto finish_return_check; + } + } + // check that any return ingredients with /same-as-ingredient connect up + // the corresponding ingredient and product in the caller. + for (int i = 0; i < SIZE(caller_instruction.products); ++i) { + if (has_property(return_inst.ingredients.at(i), "same-as-ingredient")) { + string_tree* tmp = property(return_inst.ingredients.at(i), "same-as-ingredient"); + if (!tmp || !tmp->atom) { + raise << maybe(caller.name) << "'same-as-ingredient' metadata should take exactly one value in '" << to_original_string(return_inst) << "'\n" << end(); + goto finish_return_check; + } + int ingredient_index = to_integer(tmp->value); + if (ingredient_index >= SIZE(caller_instruction.ingredients)) { + raise << maybe(caller.name) << "too few ingredients in '" << to_original_string(caller_instruction) << "'\n" << end(); + goto finish_return_check; + } + if (!is_dummy(caller_instruction.products.at(i)) && !is_literal(caller_instruction.ingredients.at(ingredient_index)) && caller_instruction.products.at(i).name != caller_instruction.ingredients.at(ingredient_index).name) { + raise << maybe(caller.name) << "'" << to_original_string(caller_instruction) << "' should write to '" << caller_instruction.ingredients.at(ingredient_index).original_string << "' rather than '" << caller_instruction.products.at(i).original_string << "'\n" << end(); + } + } + } + finish_return_check:; + } + } +} + +bool is_primitive(recipe_ordinal r) { + return r < MAX_PRIMITIVE_RECIPES; +} + +:(scenario return_type_mismatch) +% Hide_errors = true; +def main [ + 3:num <- f 2 +] +def f [ + 12:num <- next-ingredient + 13:num <- copy 35 + 14:point <- copy 12:point/raw + return 14:point +] ++error: f: return ingredient '14:point' can't be saved in '3:num' + +//: In Mu we'd like to assume that any instruction doesn't modify its +//: ingredients unless they're also products. The /same-as-ingredient inside +//: the recipe's 'return' indicates that an ingredient is intended to be +//: modified in place, and will help catch accidental misuse of such +//: 'ingredient-products' (sometimes called in-out parameters in other +//: languages). + +:(scenario return_same_as_ingredient) +% Hide_errors = true; +def main [ + 1:num <- copy 0 + 2:num <- test1 1:num # call with different ingredient and product +] +def test1 [ + 10:num <- next-ingredient + return 10:num/same-as-ingredient:0 +] ++error: main: '2:num <- test1 1:num' should write to '1:num' rather than '2:num' + +:(scenario return_same_as_ingredient_dummy) +def main [ + 1:num <- copy 0 + _ <- test1 1:num # call with different ingredient and product +] +def test1 [ + 10:num <- next-ingredient + return 10:num/same-as-ingredient:0 +] +$error: 0 + +:(code) +string to_string(const vector& in) { + if (in.empty()) return "[]"; + ostringstream out; + if (SIZE(in) == 1) { + out << no_scientific(in.at(0)); + return out.str(); + } + out << "["; + for (int i = 0; i < SIZE(in); ++i) { + if (i > 0) out << ", "; + out << no_scientific(in.at(i)); + } + out << "]"; + return out.str(); +} -- cgit 1.4.1-2-gfad0