Tested x86_64-pc-linux-gnu, applying to trunk.
-- >8 --
An experiment led me to notice that in some cases we were ending up with
TARGET_EXPR initialized by TARGET_EXPR, which isn't useful.
The target_expr_needs_replace change won't make a difference in most cases,
since cp_genericize_init will have already expanded VEC_INIT_EXPR by the
time we consider it, but it is correct.
gcc/cp/ChangeLog:
* cp-gimplify.cc (cp_fold_r) [TARGET_EXPR]: Collapse
TARGET_EXPR within TARGET_EXPR.
* constexpr.cc (cxx_eval_outermost_constant_expr): Avoid
adding redundant TARGET_EXPR.
* cp-tree.h (target_expr_needs_replace): VEC_INIT_EXPR doesn't.
---
gcc/cp/cp-tree.h | 3 ++-
gcc/cp/constexpr.cc | 4 ++--
gcc/cp/cp-gimplify.cc | 16 +++++++++++++---
3 files changed, 17 insertions(+), 6 deletions(-)
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index 3cbcdf726ca..d696fd54a7a 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -5426,7 +5426,8 @@ target_expr_needs_replace (tree t)
return false;
while (TREE_CODE (init) == COMPOUND_EXPR)
init = TREE_OPERAND (init, 1);
- return TREE_CODE (init) != AGGR_INIT_EXPR;
+ return (TREE_CODE (init) != AGGR_INIT_EXPR
+ && TREE_CODE (init) != VEC_INIT_EXPR);
}
/* True if EXPR expresses direct-initialization of a TYPE. */
diff --git a/gcc/cp/constexpr.cc b/gcc/cp/constexpr.cc
index ed41d755269..db7571d7d71 100644
--- a/gcc/cp/constexpr.cc
+++ b/gcc/cp/constexpr.cc
@@ -8065,8 +8065,8 @@ cxx_eval_outermost_constant_expr (tree t, bool
allow_non_constant,
if (TREE_CODE (t) == TARGET_EXPR
&& TARGET_EXPR_INITIAL (t) == r)
return t;
- else if (TREE_CODE (t) == CONSTRUCTOR)
- ;
+ else if (TREE_CODE (t) == CONSTRUCTOR || TREE_CODE (t) == CALL_EXPR)
+ /* Don't add a TARGET_EXPR if our argument didn't have one. */;
else if (TREE_CODE (t) == TARGET_EXPR && TARGET_EXPR_CLEANUP (t))
r = get_target_expr (r);
else
diff --git a/gcc/cp/cp-gimplify.cc b/gcc/cp/cp-gimplify.cc
index c05be833357..73548888783 100644
--- a/gcc/cp/cp-gimplify.cc
+++ b/gcc/cp/cp-gimplify.cc
@@ -1084,9 +1084,9 @@ cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_)
}
break;
- /* These are only for genericize time; they're here rather than in
- cp_genericize to avoid problems with the invisible reference
- transition. */
+ /* cp_genericize_{init,target}_expr are only for genericize time; they're
+ here rather than in cp_genericize to avoid problems with the invisible
+ reference transition. */
case INIT_EXPR:
if (data->genericize)
cp_genericize_init_expr (stmt_p);
@@ -1095,6 +1095,16 @@ cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_)
case TARGET_EXPR:
if (data->genericize)
cp_genericize_target_expr (stmt_p);
+
+ /* Folding might replace e.g. a COND_EXPR with a TARGET_EXPR; in
+ that case, use it in place of this one. */
+ if (tree &init = TARGET_EXPR_INITIAL (stmt))
+ {
+ cp_walk_tree (&init, cp_fold_r, data, NULL);
+ *walk_subtrees = 0;
+ if (TREE_CODE (init) == TARGET_EXPR)
+ *stmt_p = init;
+ }
break;
default:
base-commit: bbdcdf5cc73e1b3385d9a25bdab4df70c4bd8c2e
--
2.31.1
