From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2136) id F1600385843D; Thu, 14 Oct 2021 12:23:07 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org F1600385843D MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Aldy Hernandez To: gcc-cvs@gcc.gnu.org Subject: [gcc r12-4395] Do not call range_on_path_entry for SSAs defined within the path X-Act-Checkin: gcc X-Git-Author: Aldy Hernandez X-Git-Refname: refs/heads/master X-Git-Oldrev: d67b22e7315ca7ecfcf5e5ec3d401285d7ea25b5 X-Git-Newrev: a311163fd81babd6116e2856f4551c3ca13d8914 Message-Id: <20211014122307.F1600385843D@sourceware.org> Date: Thu, 14 Oct 2021 12:23:07 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 14 Oct 2021 12:23:08 -0000 https://gcc.gnu.org/g:a311163fd81babd6116e2856f4551c3ca13d8914 commit r12-4395-ga311163fd81babd6116e2856f4551c3ca13d8914 Author: Aldy Hernandez Date: Thu Oct 14 10:28:39 2021 +0200 Do not call range_on_path_entry for SSAs defined within the path In the path solver, when requesting the range of an SSA for which we know nothing, we ask the ranger for the range incoming to the path. We do this by asking for all the incoming ranges to the path entry block and unioning them. The problem here is that we're asking for a range on path entry for an SSA which *is* defined in the path, but for which we know nothing about: some_global.1_2 = some_global; _3 = (char) some_global.1_2; This request is causing us to ask for range_on_edge of _3 on the incoming edges to the path. This is a bit of nonsensical request because _3 isn't live on entry to the path, so ranger correctly returns UNDEFINED. The proper thing is to avoid asking this in the first place. I have added a relevant assert, since it doesn't make sense to call range_on_path_entry for SSAs defined within the path. Tested on x86-64 Linux. PR tree-optimization/102736 gcc/ChangeLog: PR tree-optimization/102736 * gimple-range-path.cc (path_range_query::range_on_path_entry): Assert that the requested range is defined outside the path. (path_range_query::ssa_range_in_phi): Do not call range_on_path_entry for SSA names that are defined within the path. gcc/testsuite/ChangeLog: * gcc.dg/tree-ssa/pr102736.c: New test. Diff: --- gcc/gimple-range-path.cc | 6 +++++- gcc/testsuite/gcc.dg/tree-ssa/pr102736.c | 21 +++++++++++++++++++++ 2 files changed, 26 insertions(+), 1 deletion(-) diff --git a/gcc/gimple-range-path.cc b/gcc/gimple-range-path.cc index 422abfddb8f..694271306a7 100644 --- a/gcc/gimple-range-path.cc +++ b/gcc/gimple-range-path.cc @@ -134,6 +134,7 @@ path_range_query::defined_outside_path (tree name) void path_range_query::range_on_path_entry (irange &r, tree name) { + gcc_checking_assert (defined_outside_path (name)); int_range_max tmp; basic_block entry = entry_bb (); bool changed = false; @@ -258,7 +259,10 @@ path_range_query::ssa_range_in_phi (irange &r, gphi *phi) // Using both the range on entry to the path, and the // range on this edge yields significantly better // results. - range_on_path_entry (r, arg); + if (defined_outside_path (arg)) + range_on_path_entry (r, arg); + else + r.set_varying (TREE_TYPE (name)); m_ranger.range_on_edge (tmp, e_in, arg); r.intersect (tmp); return; diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr102736.c b/gcc/testsuite/gcc.dg/tree-ssa/pr102736.c new file mode 100644 index 00000000000..7e556f01a86 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr102736.c @@ -0,0 +1,21 @@ +// { dg-do run } +// { dg-options "-O1 -ftree-vrp" } + +int a, b = -1, c; +int d = 1; +static inline char e(char f, int g) { return g ? f : 0; } +static inline char h(char f) { return f < a ? f : f < a; } +static inline unsigned char i(unsigned char f, int g) { return g ? f : f > g; } +void j() { +L: + c = e(1, i(h(b), d)); + if (b) + return; + goto L; +} +int main() { + j(); + if (c != 1) + __builtin_abort (); + return 0; +}