From 89b84cd794f984038984c10b03c3b0ab582f49cc Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Thu, 6 Aug 2020 12:18:24 +0200 Subject: [PATCH] tree-optimization/96491 - avoid store commoning across abnormal edges This avoids store commoning across abnormal edges since that easily can disrupt abnormal coalescing because it might create overlapping lifetime of variables. 2020-08-06 Richard Biener PR tree-optimization/96491 * tree-ssa-sink.c (sink_common_stores_to_bb): Avoid sinking across abnormal edges. * gcc.dg/torture/pr96491.c: New testcase. --- gcc/testsuite/gcc.dg/torture/pr96491.c | 29 +++++++++++++++++++++++++++++ gcc/tree-ssa-sink.c | 3 ++- 2 files changed, 31 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.dg/torture/pr96491.c diff --git a/gcc/testsuite/gcc.dg/torture/pr96491.c b/gcc/testsuite/gcc.dg/torture/pr96491.c new file mode 100644 index 0000000..784559f --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr96491.c @@ -0,0 +1,29 @@ +/* { dg-do compile } */ + +int rj; + +void __attribute__ ((returns_twice)) +da (void) +{ + rj = 1; +} + +void +c5 (void) +{ + for (;;) + ++rj; +} + +void +ls (int kz) +{ + if (kz == 0) + { + rj = 0; + c5 (); + } + + da (); + c5 (); +} diff --git a/gcc/tree-ssa-sink.c b/gcc/tree-ssa-sink.c index 962ad07..4cc5195 100644 --- a/gcc/tree-ssa-sink.c +++ b/gcc/tree-ssa-sink.c @@ -503,7 +503,8 @@ sink_common_stores_to_bb (basic_block bb) tree arg = gimple_phi_arg_def (phi, i); gimple *def = SSA_NAME_DEF_STMT (arg); if (! is_gimple_assign (def) - || stmt_can_throw_internal (cfun, def)) + || stmt_can_throw_internal (cfun, def) + || (gimple_phi_arg_edge (phi, i)->flags & EDGE_ABNORMAL)) { /* ??? We could handle some cascading with the def being another PHI. We'd have to insert multiple PHIs for -- 2.7.4