[gcc r12-2229] coroutines: Factor code. Match original source location in helpers [NFC].

[Iain D Sandoe <iains@gcc.gnu.org>]

https://gcc.gnu.org/g:d5b1bb0d197f9141a0f0e510f8d1b598c3df9552

commit r12-2229-gd5b1bb0d197f9141a0f0e510f8d1b598c3df9552
Author: Iain Sandoe <iain@sandoe.co.uk>
Date:   Wed Jul 7 19:56:20 2021 +0100

    coroutines: Factor code. Match original source location in helpers [NFC].
    
    This is primarily a source code refactoring, the only change is to
    ensure that the outlined functions are marked to begin at the same
    line as the original.  Otherwise, they get the default (which seems
    to be input_location, which corresponds to the closing brace at the
    point that this is done).  Having the source location point to that
    confuses some debuggers.
    
    This is a contributory fix to:
    PR c++/99215 - coroutines: debugging with gdb
    
    Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
    
    gcc/cp/ChangeLog:
    
            * coroutines.cc (build_actor_fn): Move common code to
            act_des_fn.
            (build_destroy_fn): Likewise.
            (act_des_fn): Build the void return here.  Ensure that the
            source location matches the original function.

Diff:
---
 gcc/cp/coroutines.cc | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/gcc/cp/coroutines.cc b/gcc/cp/coroutines.cc
index f5ae2d6d101..54ffdc8d062 100644
--- a/gcc/cp/coroutines.cc
+++ b/gcc/cp/coroutines.cc
@@ -2155,13 +2155,6 @@ build_actor_fn (location_t loc, tree coro_frame_type, tree actor, tree fnbody,
   /* One param, the coro frame pointer.  */
   tree actor_fp = DECL_ARGUMENTS (actor);
 
-  /* A void return.  */
-  tree resdecl = build_decl (loc, RESULT_DECL, 0, void_type_node);
-  DECL_ARTIFICIAL (resdecl) = 1;
-  DECL_IGNORED_P (resdecl) = 1;
-  DECL_RESULT (actor) = resdecl;
-  DECL_COROUTINE_P (actor) = 1;
-
   /* We have a definition here.  */
   TREE_STATIC (actor) = 1;
 
@@ -2532,15 +2525,8 @@ build_destroy_fn (location_t loc, tree coro_frame_type, tree destroy,
   /* One param, the coro frame pointer.  */
   tree destr_fp = DECL_ARGUMENTS (destroy);
 
-  /* A void return.  */
-  tree resdecl = build_decl (loc, RESULT_DECL, 0, void_type_node);
-  DECL_ARTIFICIAL (resdecl) = 1;
-  DECL_IGNORED_P (resdecl) = 1;
-  DECL_RESULT (destroy) = resdecl;
-
   /* We have a definition here.  */
   TREE_STATIC (destroy) = 1;
-  DECL_COROUTINE_P (destroy) = 1;
 
   tree destr_outer = push_stmt_list ();
   current_stmt_tree ()->stmts_are_full_exprs_p = 1;
@@ -4000,15 +3986,19 @@ static tree
 act_des_fn (tree orig, tree fn_type, tree coro_frame_ptr, const char* name)
 {
   tree fn_name = get_fn_local_identifier (orig, name);
+  location_t loc = DECL_SOURCE_LOCATION (orig);
   tree fn = build_lang_decl (FUNCTION_DECL, fn_name, fn_type);
   DECL_CONTEXT (fn) = DECL_CONTEXT (orig);
+  DECL_SOURCE_LOCATION (fn) = loc;
   DECL_ARTIFICIAL (fn) = true;
   DECL_INITIAL (fn) = error_mark_node;
+
   tree id = get_identifier ("frame_ptr");
   tree fp = build_lang_decl (PARM_DECL, id, coro_frame_ptr);
   DECL_CONTEXT (fp) = fn;
   DECL_ARG_TYPE (fp) = type_passed_as (coro_frame_ptr);
   DECL_ARGUMENTS (fn) = fp;
+
   /* Copy selected attributes from the original function.  */
   TREE_USED (fn) = TREE_USED (orig);
   if (DECL_SECTION_NAME (orig))
@@ -4020,6 +4010,17 @@ act_des_fn (tree orig, tree fn_type, tree coro_frame_ptr, const char* name)
   DECL_USER_ALIGN (fn) = DECL_USER_ALIGN (orig);
   /* Apply attributes from the original fn.  */
   DECL_ATTRIBUTES (fn) = copy_list (DECL_ATTRIBUTES (orig));
+
+  /* A void return.  */
+  tree resdecl = build_decl (loc, RESULT_DECL, 0, void_type_node);
+  DECL_CONTEXT (resdecl) = fn;
+  DECL_ARTIFICIAL (resdecl) = 1;
+  DECL_IGNORED_P (resdecl) = 1;
+  DECL_RESULT (fn) = resdecl;
+
+  /* This is a coroutine component.  */
+  DECL_COROUTINE_P (fn) = 1;
+
   return fn;
 }