[Tolk] Compilation pipeline, register global symbols in advance

Since I've implemented AST, now I can drop forward declarations.
Instead, I traverse AST of all files and register global symbols
(functions, constants, global vars) as a separate step, in advance.

That's why, while converting AST to Expr/Op, all available symbols are
already registered.
This greatly simplifies "intermediate state" of yet unknown functions
and checking them afterward.

Redeclaration of local variables (inside the same scope)
is now also prohibited.

tolk/pipe-generate-fif-output.cpp

@@ -0,0 +1,186 @@
+/*
+    This file is part of TON Blockchain source code.
+
+    TON Blockchain 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
+    of the License, or (at your option) any later version.
+
+    TON Blockchain 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 TON Blockchain.  If not, see <http://www.gnu.org/licenses/>.
+
+    In addition, as a special exception, the copyright holders give permission
+    to link the code of portions of this program with the OpenSSL library.
+    You must obey the GNU General Public License in all respects for all
+    of the code used other than OpenSSL. If you modify file(s) with this
+    exception, you may extend this exception to your version of the file(s),
+    but you are not obligated to do so. If you do not wish to do so, delete this
+    exception statement from your version. If you delete this exception statement
+    from all source files in the program, then also delete it here.
+*/
+#include "tolk.h"
+#include "src-file.h"
+#include "ast.h"
+#include "compiler-state.h"
+
+namespace tolk {
+
+bool SymValCodeFunc::does_need_codegen() const {
+  // when a function is declared, but not referenced from code in any way, don't generate its body
+  if (!is_really_used && G.pragma_remove_unused_functions.enabled()) {
+    return false;
+  }
+  // when a function is referenced like `var a = some_fn;` (or in some other non-call way), its continuation should exist
+  if (flags & flagUsedAsNonCall) {
+    return true;
+  }
+  // when a function f() is just `return anotherF(...args)`, it doesn't need to be codegenerated at all,
+  // since all its usages are inlined
+  return !is_just_wrapper_for_another_f();
+  // in the future, we may want to implement a true AST inlining for `inline` functions also
+}
+
+void SymValCodeFunc::set_code(CodeBlob* code) {
+  this->code = code;
+}
+
+void SymValAsmFunc::set_code(std::vector<AsmOp> code) {
+  this->ext_compile = make_ext_compile(std::move(code));
+}
+
+
+static void generate_output_func(SymDef* func_sym) {
+  SymValCodeFunc* func_val = dynamic_cast<SymValCodeFunc*>(func_sym->value);
+  tolk_assert(func_val);
+  std::string name = G.symbols.get_name(func_sym->sym_idx);
+  if (G.is_verbosity(2)) {
+    std::cerr << "\n\n=========================\nfunction " << name << " : " << func_val->get_type() << std::endl;
+  }
+  if (!func_val->code) {
+    throw ParseError(func_sym->loc, "function `" + name + "` is just declared, not implemented");
+  } else {
+    CodeBlob& code = *(func_val->code);
+    if (G.is_verbosity(3)) {
+      code.print(std::cerr, 9);
+    }
+    code.simplify_var_types();
+    if (G.is_verbosity(5)) {
+      std::cerr << "after simplify_var_types: \n";
+      code.print(std::cerr, 0);
+    }
+    code.prune_unreachable_code();
+    if (G.is_verbosity(5)) {
+      std::cerr << "after prune_unreachable: \n";
+      code.print(std::cerr, 0);
+    }
+    code.split_vars(true);
+    if (G.is_verbosity(5)) {
+      std::cerr << "after split_vars: \n";
+      code.print(std::cerr, 0);
+    }
+    for (int i = 0; i < 8; i++) {
+      code.compute_used_code_vars();
+      if (G.is_verbosity(4)) {
+        std::cerr << "after compute_used_vars: \n";
+        code.print(std::cerr, 6);
+      }
+      code.fwd_analyze();
+      if (G.is_verbosity(5)) {
+        std::cerr << "after fwd_analyze: \n";
+        code.print(std::cerr, 6);
+      }
+      code.prune_unreachable_code();
+      if (G.is_verbosity(5)) {
+        std::cerr << "after prune_unreachable: \n";
+        code.print(std::cerr, 6);
+      }
+    }
+    code.mark_noreturn();
+    if (G.is_verbosity(3)) {
+      code.print(std::cerr, 15);
+    }
+    if (G.is_verbosity(2)) {
+      std::cerr << "\n---------- resulting code for " << name << " -------------\n";
+    }
+    const char* modifier = "";
+    if (func_val->is_inline()) {
+      modifier = "INLINE";
+    } else if (func_val->is_inline_ref()) {
+      modifier = "REF";
+    }
+    std::cout << std::string(2, ' ') << name << " PROC" << modifier << ":<{\n";
+    int mode = 0;
+    if (G.settings.stack_layout_comments) {
+      mode |= Stack::_StkCmt | Stack::_CptStkCmt;
+    }
+    if (func_val->is_inline() && code.ops->noreturn()) {
+      mode |= Stack::_InlineFunc;
+    }
+    if (func_val->is_inline() || func_val->is_inline_ref()) {
+      mode |= Stack::_InlineAny;
+    }
+    code.generate_code(std::cout, mode, 2);
+    std::cout << std::string(2, ' ') << "}>\n";
+    if (G.is_verbosity(2)) {
+      std::cerr << "--------------\n";
+    }
+  }
+}
+
+void pipeline_generate_fif_output_to_std_cout() {
+  std::cout << "\"Asm.fif\" include\n";
+  std::cout << "// automatically generated from " << G.generated_from << std::endl;
+  std::cout << "PROGRAM{\n";
+
+  for (SymDef* func_sym : G.all_code_functions) {
+    SymValCodeFunc* func_val = dynamic_cast<SymValCodeFunc*>(func_sym->value);
+    tolk_assert(func_val);
+    if (!func_val->does_need_codegen()) {
+      if (G.is_verbosity(2)) {
+        std::cerr << func_sym->name() << ": code not generated, function does not need codegen\n";
+      }
+      continue;
+    }
+
+    std::string name = G.symbols.get_name(func_sym->sym_idx);
+    std::cout << std::string(2, ' ');
+    if (func_val->method_id.is_null()) {
+      std::cout << "DECLPROC " << name << "\n";
+    } else {
+      std::cout << func_val->method_id << " DECLMETHOD " << name << "\n";
+    }
+  }
+
+  for (SymDef* gvar_sym : G.all_global_vars) {
+    auto* glob_val = dynamic_cast<SymValGlobVar*>(gvar_sym->value);
+    tolk_assert(glob_val);
+    if (!glob_val->is_really_used && G.pragma_remove_unused_functions.enabled()) {
+      if (G.is_verbosity(2)) {
+        std::cerr << gvar_sym->name() << ": variable not generated, it's unused\n";
+      }
+      continue;
+    }
+    std::string name = G.symbols.get_name(gvar_sym->sym_idx);
+    std::cout << std::string(2, ' ') << "DECLGLOBVAR " << name << "\n";
+  }
+
+  for (SymDef* func_sym : G.all_code_functions) {
+    SymValCodeFunc* func_val = dynamic_cast<SymValCodeFunc*>(func_sym->value);
+    if (!func_val->does_need_codegen()) {
+      continue;
+    }
+    generate_output_func(func_sym);
+  }
+
+  std::cout << "}END>c\n";
+  if (!G.settings.boc_output_filename.empty()) {
+    std::cout << "boc>B \"" << G.settings.boc_output_filename << "\" B>file\n";
+  }
+}
+
+} // namespace tolk