Message ID | 5f8a85e0-71a3-0394-6f1a-18633cd6c71a@redhat.com |
---|---|
State | New |
Headers | show |
Series | PR tree-optimization/108520 - Add function context for querying global ranges. | expand |
On Fri, Feb 10, 2023 at 1:02 AM Andrew MacLeod via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > I was about to ping on this, and then found it in my drafts.. Doh! > > > get_range_global() can invoke tree.cc::nonnull_arg_p() if the item being > queried is a pointer and a parameter. This routine assumes the context > is CFUN, and this is not always true. Can you share the backtrace where the context is different and cfun not NULL? I'm curious .. > This patch simply adds a function context to the get_range_global query, > and defaults it to cfun. If the context passed in is anything different > than cfun, then it simply chooses not to invoke nonnull_arg_p(). > > The check_assume function now directly calls gimple_range_global with > the correct function context instead of indirectly calling it through > the global_range_query->range_of_expr () method. Thats all it should > have been doing in the first place really since its always an ssa name. > > Bootstraps on x86_64-pc-linux-gnu with no regressions. OK for trunk? OK. Note that in the end nonnull_arg_p should get a struct function argument as well, and its flag_delete_null_pointer_checks then need to become opt_for_fn (fn->decl, flag_delete_null_pointer_checks). I'll also note that for functions with many arguments nonnull_arg_p is quite expensive and nonnull_arg_p on a PARM_DECL default-def should be reflected on its range by a pass and we shouldn't re-query this in any on-demand called function. Richard. > Andrew > >
On 2/10/23 02:45, Richard Biener wrote: > On Fri, Feb 10, 2023 at 1:02 AM Andrew MacLeod via Gcc-patches > <gcc-patches@gcc.gnu.org> wrote: >> I was about to ping on this, and then found it in my drafts.. Doh! >> >> >> get_range_global() can invoke tree.cc::nonnull_arg_p() if the item being >> queried is a pointer and a parameter. This routine assumes the context >> is CFUN, and this is not always true. > Can you share the backtrace where the context is different and cfun not NULL? > I'm curious .. Its from the assume pass when we are trying to map the actual p[aramater passed to a function with the global value we assigned to the parameter in that function.ie // determine x has a global range of [10, 200] in this function. assume_func (int x) { if (x>=10 || x<=200) return 1; else return 0; } myfunc() { int y_3 assume_func (y_3) // Here, we lookup assume_fund parameter list, and assign [10,200] // to the range of y_3 via the inferred range mechanism } The traceback is: 0x1e77e95 nonnull_arg_p(tree_node const*) /gcc/master/gcc/gcc/tree.cc:14438 0x1e96241 get_range_global /gcc/master/gcc/gcc/value-query.cc:330 0x1e96668 global_range_query::range_of_expr(vrange&, tree_node*, gimple*) /gcc/master/gcc/gcc/value-query.cc:406 0x32483c4 gimple_infer_range::check_assume_func(gcall*) /gcc/master/gcc/gcc/gimple-range-infer.cc:87 0x32488e8 gimple_infer_range::gimple_infer_range(gimple*) /gcc/master/gcc/gcc/gimple-range-infer.cc:166 0x3249635 infer_range_manager::register_all_uses(tree_node*) /gcc/master/gcc/gcc/gimple-range-infer.cc:374 0x3248e94 infer_range_manager::has_range_p(tree_node*, basic_block_def*) /gcc/master/gcc/gcc/gimple-range-infer.cc:273 0x3248f7e infer_range_manager::maybe_adjust_range(vrange&, tree_node*, basic_block_def*) /gcc/master/gcc/gcc/gimple-range-infer.cc:290 0x1c8b6e1 path_range_query::adjust_for_non_null_uses(basic_block_def*) /gcc/master/gcc/gcc/gimple-range-path.cc:501 0x1c8bf23 path_range_query::compute_ranges(bitmap_head const*) /gcc/master/gcc/gcc/gimple-range-path.cc:622 0x1c8a40a path_range_query::reset_path(vec<basic_block_def*, va_heap, vl_ptr> const&, bitmap_head const*) /gcc/master/gcc/gcc/gimple-range-path.cc:229 0x1c89af0 path_range_query::path_range_query(gimple_ranger&, vec<basic_block_def*, va_heap, vl_ptr> const&, bitmap_head const*, bool) /gcc/master/gcc/gcc/gimple-range-path.cc:50 0x1d52a96 back_threader::find_taken_edge_cond(vec<basic_block_def*, va_heap, vl_ptr> const&, gcond*) /gcc/master/gcc/gcc/tree-ssa-threadbackward.cc:324 >> This patch simply adds a function context to the get_range_global query, >> and defaults it to cfun. If the context passed in is anything different >> than cfun, then it simply chooses not to invoke nonnull_arg_p(). >> >> The check_assume function now directly calls gimple_range_global with >> the correct function context instead of indirectly calling it through >> the global_range_query->range_of_expr () method. Thats all it should >> have been doing in the first place really since its always an ssa name. >> >> Bootstraps on x86_64-pc-linux-gnu with no regressions. OK for trunk? > OK. > > Note that in the end nonnull_arg_p should get a struct function argument > as well, and its flag_delete_null_pointer_checks then need to become > opt_for_fn (fn->decl, flag_delete_null_pointer_checks). > > I'll also note that for functions with many arguments nonnull_arg_p is > quite expensive and nonnull_arg_p on a PARM_DECL default-def > should be reflected on its range by a pass and we shouldn't re-query > this in any on-demand called function. At the moment, Its only being queried thjis way as we try to resolve these assume_functions. IF we enhance this to utilize IPA information next release in a similar way, it'll become more prevalent
From e64f04f15a47ef91a21668318728a49a90e8dae1 Mon Sep 17 00:00:00 2001 From: Andrew MacLeod <amacleod@redhat.com> Date: Mon, 6 Feb 2023 13:07:01 -0500 Subject: [PATCH] Add function context for querying global ranges. When processing arguments for assume functions, call get_global_range directly and utilize a function context pointer to avoid any assumptions about using cfun. PR tree-optimization/108520 gcc/ * gimple-range-infer.cc (check_assume_func): Invoke gimple_range_global directly instead using global_range_query. * value-query.cc (get_range_global): Add function context and avoid calling nonnull_arg_p if not cfun. (gimple_range_global): Add function context pointer. * value-query.h (imple_range_global): Add function context. gcc/testsuite/ * g++.dg/pr108520.C: New. --- gcc/gimple-range-infer.cc | 2 +- gcc/testsuite/g++.dg/pr108520.C | 17 +++++++++++++++++ gcc/value-query.cc | 10 +++++----- gcc/value-query.h | 4 +++- 4 files changed, 26 insertions(+), 7 deletions(-) create mode 100644 gcc/testsuite/g++.dg/pr108520.C diff --git a/gcc/gimple-range-infer.cc b/gcc/gimple-range-infer.cc index 4677ae21ccc..c765e072731 100644 --- a/gcc/gimple-range-infer.cc +++ b/gcc/gimple-range-infer.cc @@ -84,7 +84,7 @@ gimple_infer_range::check_assume_func (gcall *call) continue; // Query the global range of the default def in the assume function. Value_Range assume_range (type); - global_ranges.range_of_expr (assume_range, default_def); + gimple_range_global (assume_range, default_def, fun); // If there is a non-varying result, add it as an inferred range. if (!assume_range.varying_p ()) { diff --git a/gcc/testsuite/g++.dg/pr108520.C b/gcc/testsuite/g++.dg/pr108520.C new file mode 100644 index 00000000000..6cd677a852d --- /dev/null +++ b/gcc/testsuite/g++.dg/pr108520.C @@ -0,0 +1,17 @@ +// { dg-do compile { target c++23 } } +// { dg-options "-O2" } + +static void foo () {} +struct S { void (*f) (); }; + +[[gnu::nonnull (1)]] +void +bar (void *x) +{ + struct S a[3] = { { foo }, { foo }, { foo } }; + for (struct S *i = a, *e = a + 3; i != e; i++) + { + [[assume (i->f)]]; + i->f (); + } +} diff --git a/gcc/value-query.cc b/gcc/value-query.cc index 5345bb47718..f936e878080 100644 --- a/gcc/value-query.cc +++ b/gcc/value-query.cc @@ -312,7 +312,7 @@ get_ssa_name_ptr_info_nonnull (const_tree name) // return VARYING. static void -get_range_global (vrange &r, tree name) +get_range_global (vrange &r, tree name, struct function *fun = cfun) { tree type = TREE_TYPE (name); @@ -327,7 +327,7 @@ get_range_global (vrange &r, tree name) // anti-ranges for pointers. Note that this is only valid with // default definitions of PARM_DECLs. if (POINTER_TYPE_P (type) - && ((cfun && nonnull_arg_p (sym)) + && ((cfun && fun == cfun && nonnull_arg_p (sym)) || get_ssa_name_ptr_info_nonnull (name))) r.set_nonzero (type); else if (!POINTER_TYPE_P (type)) @@ -378,15 +378,15 @@ get_range_global (vrange &r, tree name) // https://gcc.gnu.org/pipermail/gcc-patches/2021-June/571709.html void -gimple_range_global (vrange &r, tree name) +gimple_range_global (vrange &r, tree name, struct function *fun) { tree type = TREE_TYPE (name); gcc_checking_assert (TREE_CODE (name) == SSA_NAME); - if (SSA_NAME_IS_DEFAULT_DEF (name) || (cfun && cfun->after_inlining) + if (SSA_NAME_IS_DEFAULT_DEF (name) || (fun && fun->after_inlining) || is_a<gphi *> (SSA_NAME_DEF_STMT (name))) { - get_range_global (r, name); + get_range_global (r, name, fun); return; } r.set_varying (type); diff --git a/gcc/value-query.h b/gcc/value-query.h index 03be0be9178..63878968118 100644 --- a/gcc/value-query.h +++ b/gcc/value-query.h @@ -143,6 +143,8 @@ get_range_query (const struct function *fun) return fun->x_range_query ? fun->x_range_query : &global_ranges; } -extern void gimple_range_global (vrange &v, tree name); +// Query the global range of NAME in function F. Default to cfun. +extern void gimple_range_global (vrange &v, tree name, + struct function *f = cfun); #endif // GCC_QUERY_H -- 2.39.0