From c85aaf2cbe9da50e23655a8082a37166adf4c0f7 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Fri, 4 Mar 2022 15:14:59 +0100 Subject: gimplify: Clear TREE_READONLY on automatic vars being stored into [PR104529] The following testcase regressed when SRA started punting on stores to TREE_READONLY vars. We document that: "In a VAR_DECL, PARM_DECL or FIELD_DECL, or any kind of ..._REF node, nonzero means it may not be the lhs of an assignment." so the SRA change looks desirable. On the other side, at least in this testcase the TREE_READONLY is set there intentionally from the PR85873 fix, because gimplify_init_constructor itself uses TREE_READONLY on the object to determine if it can perform promotion to static const or not. So, similarly to other spots in the gimplifier where we also clear TREE_READONLY when we emit IL that stores into the object, this does the same in gimplify_init_constructor, but in the way so that the TREE_READONLY test for the promotion to static const keeps working and doesn't change anything for notify_temp_creation mode, which doesn't emit any IL, just tests if it would need a temporary or not. This keeps PR85873 testcase working as before and fixes this regression. 2022-03-04 Jakub Jelinek PR middle-end/104529 * gimplify.cc (gimplify_init_constructor): Clear TREE_READONLY on automatic objects which will be runtime initialized. * g++.dg/tree-ssa/pr104529.C: New test. --- gcc/gimplify.cc | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'gcc/gimplify.cc') diff --git a/gcc/gimplify.cc b/gcc/gimplify.cc index be8f0d3..c6ba0c3 100644 --- a/gcc/gimplify.cc +++ b/gcc/gimplify.cc @@ -5120,6 +5120,12 @@ gimplify_init_constructor (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p, { if (notify_temp_creation) return GS_OK; + + /* The var will be initialized and so appear on lhs of + assignment, it can't be TREE_READONLY anymore. */ + if (VAR_P (object)) + TREE_READONLY (object) = 0; + is_empty_ctor = true; break; } @@ -5171,6 +5177,11 @@ gimplify_init_constructor (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p, break; } + /* The var will be initialized and so appear on lhs of + assignment, it can't be TREE_READONLY anymore. */ + if (VAR_P (object) && !notify_temp_creation) + TREE_READONLY (object) = 0; + /* If there are "lots" of initialized elements, even discounting those that are not address constants (and thus *must* be computed at runtime), then partition the constructor into -- cgit v1.1