Add support for try/catch

Author: antoyo

gcc/dwarf2asm.cc

@@ -1159,4 +1159,14 @@ dw2_asm_output_encoded_addr_rtx (int encoding, rtx addr, bool is_public,
   va_end (ap);
 }
 
+void dwarf2asm_cc_finalize (void)
+{
+  if (indirect_pool)
+  {
+    indirect_pool->empty();
+    indirect_pool = NULL;
+  }
+  dw2_const_labelno = 0;
+}
+
 #include "gt-dwarf2asm.h"

gcc/dwarf2asm.h

@@ -86,6 +86,8 @@ extern const char *eh_data_format_name (int);
 extern rtx dw2_force_const_mem (rtx, bool);
 extern void dw2_output_indirect_constants (void);
 
+void dwarf2asm_cc_finalize (void);
+
 /* These are currently unused.  */
 
 #if 0

gcc/dwarf2out.cc

@@ -1003,6 +1003,9 @@ dwarf2out_do_cfi_startproc (bool second)
 	  if (targetm.asm_out.make_eh_symbol_indirect != NULL)
 	    ref = targetm.asm_out.make_eh_symbol_indirect (ref, true);
 	  else
+            // TODO: HERE: should not insert multiple times the same personality function.
+            // If we don't, we segfault later, possibly because we don't generate the info for the duplicates.
+            // I'm not sure why it's attempting to insert multiple times the same personality function.
 	    ref = dw2_force_const_mem (ref, true);
 	}
 

gcc/jit/dummy-frontend.cc

@@ -605,14 +605,21 @@ jit_langhook_init (void)
 
   build_common_tree_nodes (flag_signed_char);
 
+  /* I don't know why this has to be done explicitly.  */
+  void_list_node = build_tree_list (NULL_TREE, void_type_node);
+
+  target_builtins.empty ();
   build_common_builtin_nodes ();
 
+  /* Initialize EH, if we've been told to do so.  */
+  if (flag_exceptions)
+    using_eh_for_cleanups ();
+
   /* The default precision for floating point numbers.  This is used
      for floating point constants with abstract type.  This may
      eventually be controllable by a command line option.  */
   mpfr_set_default_prec (256);
 
-  target_builtins.empty ();
   targetm.init_builtins ();
 
   return true;

gcc/jit/jit-playback.cc

@@ -568,6 +568,7 @@ new_function (location *loc,
 
   /* FIXME: this uses input_location: */
   tree fndecl = build_fn_decl (name, fn_type);
+  TREE_NOTHROW (fndecl) = 0;
 
   if (loc)
     set_tree_location (fndecl, loc);
@@ -2153,6 +2154,15 @@ playback::function::get_address (location *loc)
   return new rvalue (m_ctxt, t_fnptr);
 }
 
+/* Construct a new local within this playback::function.  */
+
+void
+playback::function::
+set_personality_function (function *personality_function)
+{
+  DECL_FUNCTION_PERSONALITY (m_inner_fndecl) = personality_function->as_fndecl ();
+}
+
 /* Build a statement list for the function as a whole out of the
    lists of statements for the individual blocks, building labels
    for each block.  */
@@ -2171,6 +2181,11 @@ build_stmt_list ()
       int j;
       tree stmt;
 
+      // Do not add try/catch block to the function.
+      // TODO: explain why.
+      if (b->m_is_try_or_catch)
+        continue;
+
       b->m_label_expr = build1 (LABEL_EXPR,
 				void_type_node,
 				b->as_label_decl ());
@@ -2269,6 +2284,70 @@ add_eval (location *loc,
   add_stmt (rvalue->as_tree ());
 }
 
+
+void
+playback::block::
+add_try_catch (location *loc,
+         block *try_block,
+         block *catch_block,
+         bool is_finally)
+{
+  gcc_assert (try_block);
+  gcc_assert (catch_block);
+
+  try_block->m_is_try_or_catch = true;
+  catch_block->m_is_try_or_catch = true;
+
+  if (loc)
+  {
+    set_tree_location (try_block->as_label_decl (), loc);
+    set_tree_location (catch_block->as_label_decl (), loc);
+  }
+
+  tree try_body = alloc_stmt_list ();
+  int i;
+  tree stmt;
+  FOR_EACH_VEC_ELT (try_block->m_stmts, i, stmt) {
+    append_to_statement_list (stmt, &try_body);
+  }
+
+  tree catch_body = alloc_stmt_list ();
+  int j;
+  tree catch_stmt;
+  FOR_EACH_VEC_ELT (catch_block->m_stmts, j, catch_stmt) {
+    append_to_statement_list (catch_stmt, &catch_body);
+  }
+
+  if (is_finally)
+  {
+    tree success_body = alloc_stmt_list ();
+
+    // TODO: find a better way to keep the EH_ELSE_EXPR than creating an empty inline asm.
+  tree t_string = build_string ("");
+  tree asm_stmt
+    = build5 (ASM_EXPR, void_type_node, t_string, NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE);
+
+  // asm statements without outputs, including simple ones, are treated
+  //   as volatile.
+  ASM_VOLATILE_P (asm_stmt) = 1;
+  ASM_INPUT_P (asm_stmt) = 0;
+    append_to_statement_list (asm_stmt, &success_body);
+
+    // TODO: Don't automatically add the `EH_ELSE_EXPR`. Make an API to create such a node and let the user of libgccjit
+    // add it manually.
+    catch_body = build2 (EH_ELSE_EXPR, void_type_node, success_body, catch_body);
+    add_stmt (build2 (TRY_FINALLY_EXPR, void_type_node,
+            try_body, catch_body));
+  }
+  else
+  {
+    catch_body = build2(CATCH_EXPR, void_type_node, NULL, catch_body);
+    tree try_catch = build2 (TRY_CATCH_EXPR, void_type_node,
+            try_body, catch_body);
+    add_stmt (try_catch);
+  }
+}
+
 /* Add an assignment to the function's statement list.  */
 
 void

gcc/jit/jit-playback.h

@@ -536,6 +536,9 @@ class function : public wrapper
   rvalue *
   get_address (location *loc);
 
+  void
+  set_personality_function (function *personality_function);
+
   void
   build_stmt_list ();
 
@@ -606,6 +609,12 @@ class block : public wrapper
   add_eval (location *loc,
 	    rvalue *rvalue);
 
+  void
+  add_try_catch (location *loc,
+		 block *try_block,
+		 block *catch_block,
+		 bool is_finally);
+
   void
   add_assignment (location *loc,
 		  lvalue *lvalue,
@@ -669,6 +678,7 @@ class block : public wrapper
 
 public: // for now
   tree m_label_expr;
+  bool m_is_try_or_catch = false;
 
   friend class function;
 };

gcc/jit/jit-recording.cc

@@ -4244,6 +4244,36 @@ recording::function::replay_into (replayer *r)
 				     m_string_attributes));
 }
 
+/* Implementation of recording::memento::make_debug_string for
+   setting a personality function.  */
+
+recording::string *
+recording::memento_of_set_personality_function::make_debug_string ()
+{
+  return string::from_printf (m_ctxt,
+			      "%s",
+			      m_personality_function->get_debug_string ());
+}
+
+/* Implementation of recording::memento::write_reproducer for setting the personality function. */
+
+void
+recording::memento_of_set_personality_function::write_reproducer (reproducer &r)
+{
+  r.write ("    gcc_jit_function_set_personality_function (%s,\n"
+	   "                                               %s);\n",
+	   r.get_identifier (m_function),
+	   r.get_identifier (m_personality_function));
+}
+
+void
+recording::function::set_personality_function (function *function)
+{
+  recording::memento_of_set_personality_function *result =
+    new memento_of_set_personality_function (m_ctxt, this, function);
+  m_ctxt->record (result);
+}
+
 /* Create a recording::local instance and add it to
    the functions's context's list of mementos, and to the function's
    list of locals.
@@ -4386,6 +4416,13 @@ recording::function::validate ()
       /* Iteratively walk the graph of blocks, marking their "m_is_reachable"
 	 flag, starting at the initial block.  */
       auto_vec<block *> worklist (m_blocks.length ());
+      int j;
+      block *func_block;
+      /* Push the blocks used in try/catch because they're not successors of
+         other blocks.  */
+      FOR_EACH_VEC_ELT (m_blocks, j, func_block)
+      if (func_block->m_is_reachable)
+	worklist.safe_push (func_block);
       worklist.safe_push (m_blocks[0]);
       while (worklist.length () > 0)
 	{
@@ -4581,6 +4618,27 @@ recording::block::add_eval (recording::location *loc,
   return result;
 }
 
+/* The implementation of class gcc::jit::recording::block.  */
+
+/* Create a recording::try_catch instance and add it to
+   the block's context's list of mementos, and to the block's
+   list of statements.
+   Implements the heart of gcc_jit_block_add_try_catch.  */
+
+recording::statement *
+recording::block::add_try_catch (location *loc,
+                   block *try_block,
+                   block *catch_block,
+                   bool is_finally)
+{
+  statement *result = new try_catch (this, loc, try_block, catch_block, is_finally);
+  try_block->m_is_reachable = true;
+  catch_block->m_is_reachable = true;
+  m_ctxt->record (result);
+  m_statements.safe_push (result);
+  return result;
+}
+
 /* Create a recording::assignment instance and add it to
    the block's context's list of mementos, and to the block's
    list of statements.
@@ -6997,6 +7055,17 @@ recording::statement::write_to_dump (dump &d)
     m_loc = d.make_location ();
 }
 
+/* The implementation of class gcc::jit::recording::memento_of_set_personality_function.  */
+
+/* Implementation of pure virtual hook recording::memento::replay_into
+   for recording::memento_of_set_personality_function.  */
+
+void
+recording::memento_of_set_personality_function::replay_into (replayer *r)
+{
+  m_function->playback_function ()->set_personality_function (m_personality_function->playback_function ());
+}
+
 /* The implementation of class gcc::jit::recording::eval.  */
 
 /* Implementation of pure virtual hook recording::memento::replay_into
@@ -7035,6 +7104,59 @@ recording::eval::write_reproducer (reproducer &r)
 	   r.get_identifier_as_rvalue (m_rvalue));
 }
 
+/* The implementation of class gcc::jit::recording::try_catch.  */
+
+/* Implementation of pure virtual hook recording::memento::replay_into
+   for recording::try_catch.  */
+
+void
+recording::try_catch::replay_into (replayer *r)
+{
+  playback_block (get_block ())
+    ->add_try_catch (playback_location (r),
+        m_try_block->playback_block (),
+        m_catch_block->playback_block (),
+        m_is_finally);
+}
+
+/* Implementation of recording::memento::make_debug_string for
+   an eval statement.  */
+
+recording::string *
+recording::try_catch::make_debug_string ()
+{
+  if (m_is_finally)
+    return string::from_printf (m_ctxt,
+                  "try { %s } finally { %s };",
+                  m_try_block->get_debug_string (),
+                  m_catch_block->get_debug_string ());
+  else
+    return string::from_printf (m_ctxt,
+                  "try { %s } catch { %s };",
+                  m_try_block->get_debug_string (),
+                  m_catch_block->get_debug_string ());
+}
+
+/* Implementation of recording::memento::write_reproducer for
+   eval statements.  */
+
+void
+recording::try_catch::write_reproducer (reproducer &r)
+{
+  const char *func_name = "gcc_jit_block_add_try_catch";
+  if (m_is_finally)
+    func_name = "gcc_jit_block_add_try_finally";
+  r.write ("  %s (%s, /*gcc_jit_block *block */\n"
+       "                                 %s, /* gcc_jit_location *loc */\n"
+       "                                 %s, /* gcc_jit_block *try_block */\n"
+       "                                 %s); /* gcc_jit_block *catch_block */\n",
+       func_name,
+       r.get_identifier (get_block ()),
+       r.get_identifier (get_loc ()),
+       r.get_identifier (m_try_block),
+       r.get_identifier (m_catch_block));
+}
+
 /* The implementation of class gcc::jit::recording::assignment.  */
 
 /* Implementation of pure virtual hook recording::memento::replay_into