The earlier patch for PR112938 arranged for volatile parms to be made indirect in internal strub wrapped bodies.
The first problem that remained, more evident, was that the indirected parameter remained volatile, despite the indirection, but it wasn't regimplified, so indirecting it was malformed gimple. Regimplifying turned out not to be needed. The best course of action was to drop the volatility from the by-reference parm, that was being unexpectedly inherited from the original volatile parm. That exposed another problem: the dereferences would then lose their volatile status, so we had to bring volatile back to them. Regstrapped on x86_64-linux-gnu. Ok to install? for gcc/ChangeLog PR middle-end/112938 * ipa-strub.cc (pass_ipa_strub::execute): Drop volatility from indirected parm. (maybe_make_indirect): Restore volatility in dereferences. for gcc/testsuite/ChangeLog PR middle-end/112938 * g++.dg/strub-internal-pr112938.cc: New. --- gcc/ipa-strub.cc | 7 +++++++ gcc/testsuite/g++.dg/strub-internal-pr112938.cc | 12 ++++++++++++ 2 files changed, 19 insertions(+) create mode 100644 gcc/testsuite/g++.dg/strub-internal-pr112938.cc diff --git a/gcc/ipa-strub.cc b/gcc/ipa-strub.cc index dff94222351ad..8fa7bdf530023 100644 --- a/gcc/ipa-strub.cc +++ b/gcc/ipa-strub.cc @@ -1940,6 +1940,9 @@ maybe_make_indirect (indirect_parms_t &indirect_parms, tree op, int *rec) TREE_TYPE (TREE_TYPE (op)), op, build_int_cst (TREE_TYPE (op), 0)); + if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (op))) + && !TREE_THIS_VOLATILE (ret)) + TREE_SIDE_EFFECTS (ret) = TREE_THIS_VOLATILE (ret) = 1; return ret; } } @@ -2894,6 +2897,10 @@ pass_ipa_strub::execute (function *) probably drop the TREE_ADDRESSABLE and keep the TRUE. */ tree ref_type = build_ref_type_for (nparm); + if (TREE_THIS_VOLATILE (nparm) + && TYPE_VOLATILE (TREE_TYPE (nparm)) + && !TYPE_VOLATILE (ref_type)) + TREE_SIDE_EFFECTS (nparm) = TREE_THIS_VOLATILE (nparm) = 0; DECL_ARG_TYPE (nparm) = TREE_TYPE (nparm) = ref_type; relayout_decl (nparm); TREE_ADDRESSABLE (nparm) = 0; diff --git a/gcc/testsuite/g++.dg/strub-internal-pr112938.cc b/gcc/testsuite/g++.dg/strub-internal-pr112938.cc new file mode 100644 index 0000000000000..5a74becc2697e --- /dev/null +++ b/gcc/testsuite/g++.dg/strub-internal-pr112938.cc @@ -0,0 +1,12 @@ +/* { dg-do compile } */ +/* { dg-options "-fdump-tree-optimized -O2" } */ +/* { dg-require-effective-target strub } */ + +bool __attribute__ ((__strub__ ("internal"))) +f(bool i, volatile bool j) +{ + return (i ^ j) == j; +} + +/* Check for two dereferences of the indirected volatile j parm. */ +/* { dg-final { scan-tree-dump-times {={v} \*j_[0-9][0-9]*(D)} 2 "optimized" } } */ -- Alexandre Oliva, happy hacker https://FSFLA.org/blogs/lxo/ Free Software Activist GNU Toolchain Engineer More tolerance and less prejudice are key for inclusion and diversity Excluding neuro-others for not behaving ""normal"" is *not* inclusive