From c76b3f9e83353a4cd437ca137c1fb835c9b5c21f Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Thu, 26 Nov 2020 16:13:08 +0100 Subject: [PATCH] tree-optimization/97953 - fix bougs range recorded by EVRP EVRP records some ranges from asserts into SSA_NAME_RANGE_INFO but fails to assert that the condition the range is derived from is always true after the SSA names definition. The patch implements the simplest post-dominance check, basic-block equality. 2020-11-26 Richard Biener PR tree-optimization/97953 * gimple-ssa-evrp-analyze.c (evrp_range_analyzer::record_ranges_from_incoming_edge): Make sure the condition post-dominates the SSA definition before recording into SSA_NAME_RANGE_INFO. * gcc.dg/pr97953.c: New testcase. --- gcc/gimple-ssa-evrp-analyze.c | 6 +++++- gcc/testsuite/gcc.dg/pr97953.c | 24 ++++++++++++++++++++++++ 2 files changed, 29 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.dg/pr97953.c diff --git a/gcc/gimple-ssa-evrp-analyze.c b/gcc/gimple-ssa-evrp-analyze.c index 485774d..b998e0b 100644 --- a/gcc/gimple-ssa-evrp-analyze.c +++ b/gcc/gimple-ssa-evrp-analyze.c @@ -218,7 +218,11 @@ evrp_range_analyzer::record_ranges_from_incoming_edge (basic_block bb) push_value_range (vrs[i].first, vrs[i].second); if (is_fallthru && m_update_global_ranges - && all_uses_feed_or_dominated_by_stmt (vrs[i].first, stmt)) + && all_uses_feed_or_dominated_by_stmt (vrs[i].first, stmt) + /* The condition must post-dominate the definition point. */ + && (SSA_NAME_IS_DEFAULT_DEF (vrs[i].first) + || (gimple_bb (SSA_NAME_DEF_STMT (vrs[i].first)) + == pred_e->src))) { set_ssa_range_info (vrs[i].first, vrs[i].second); maybe_set_nonzero_bits (pred_e, vrs[i].first); diff --git a/gcc/testsuite/gcc.dg/pr97953.c b/gcc/testsuite/gcc.dg/pr97953.c new file mode 100644 index 0000000..6219619 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr97953.c @@ -0,0 +1,24 @@ +/* { dg-do run } */ +/* { dg-options "-O2 -fno-tree-fre" } */ + +int __attribute__((noipa)) +foo (int flag, int *p) +{ + int val = *p; + if (flag) + { + if (val != 1) + __builtin_unreachable (); + return 0; + } + int val2 = *p; + return val2 == 2; +} + +int main() +{ + int i = 2; + if (foo (0, &i) != 1) + __builtin_abort (); + return 0; +} -- 2.7.4