| Message ID | 0da5fc53-8858-18ad-1fc4-b3aeb3c46f12@arm.com |
|---|---|
| State | New |
| Headers | show |
| Series | [vect] PR92317: fix skip_epilogue creation for epilogues | expand |
Sorry for the double post, ignore please. On 06/11/2019 10:57, Andre Vieira (lists) wrote: > Hi, > > When investigating PR92317 I noticed that when we create the skip > epilogue condition, see ('if (skip_epilog)' in 'vect_do_peeling'), we > only copy phi-nodes that are not constants in > 'slpeel_update_phi_nodes_for_guard2'. This can cause problems later > when we create the scalar epilogue for this epilogue, since if the > 'scalar_loop' is not the same as 'loop' > 'slpeel_tree_duplicate_loop_to_edge_cfg' will expect both to have > identical single_exit bb's and use that to copy the current_def > meta_data of phi-nodes. > > This makes sure that is true even if these phi-nodes are constants, > fixing PR92317. I copied the failing testcase and added the options > that originally made it fail. > > Is this OK for trunk? > > Cheers, > Andre > > gcc/ChangeLog: > > 2019-11-06 Andre Vieira <andre.simoesdiasvieira@arm.com> > > * tree-vect-loop-manip.c (slpeel_update_phi_nodes_for_guard2): Also > update phi's with constant phi arguments. > > > gcc/testsuite/ChangeLog: > 2019-11-06 Andre Vieira <andre.simoesdiasvieira@arm.com> > > * gcc/testsuite/g++.dg/opt/pr92317.C
diff --git a/gcc/testsuite/g++.dg/opt/pr92317.C b/gcc/testsuite/g++.dg/opt/pr92317.C new file mode 100644 index 0000000000000000000000000000000000000000..2bb9729fc961a998db9a88045ee04a81e12b07a8 --- /dev/null +++ b/gcc/testsuite/g++.dg/opt/pr92317.C @@ -0,0 +1,51 @@ +// Copied from pr87967.C +// { dg-do compile { target c++11 } } +// { dg-options "-O2 -ftree-vectorize -fno-tree-pre --param vect-epilogues-nomask=1" } + +void h(); +template <typename b> struct k { using d = b; }; +template <typename b, template <typename> class> using e = k<b>; +template <typename b, template <typename> class f> +using g = typename e<b, f>::d; +struct l { + template <typename i> using ab = typename i::j; +}; +struct n : l { + using j = g<char *, ab>; +}; +class o { +public: + long r(); +}; +char m; +char s() { + if (m) + return '0'; + return 'A'; +} +class t { +public: + typedef char *ad; + ad m_fn2(); +}; +void fn3() { + char *a; + t b; + bool p = false; + while (*a) { + h(); + o c; + if (*a) + a++; + if (c.r()) { + n::j q; + for (t::ad d = b.m_fn2(), e; d != e; d++) { + char f = *q; + *d = f + s(); + } + p = true; + } + } + if (p) + throw; +} diff --git a/gcc/tree-vect-loop-manip.c b/gcc/tree-vect-loop-manip.c index 1fbcaf2676f3a099cccc5d4f63e18f4a689abeff..54f3ccf3ec373b5621e7778e6e80bab853a57687 100644 --- a/gcc/tree-vect-loop-manip.c +++ b/gcc/tree-vect-loop-manip.c @@ -2291,12 +2291,14 @@ slpeel_update_phi_nodes_for_guard2 (class loop *loop, class loop *epilog, { gphi *update_phi = gsi.phi (); tree old_arg = PHI_ARG_DEF (update_phi, 0); - /* This loop-closed-phi actually doesn't represent a use out of the - loop - the phi arg is a constant. */ - if (TREE_CODE (old_arg) != SSA_NAME) - continue; - tree merge_arg = get_current_def (old_arg); + tree merge_arg = NULL_TREE; + + /* If the old argument is a SSA_NAME use its current_def. */ + if (TREE_CODE (old_arg) == SSA_NAME) + merge_arg = get_current_def (old_arg); + /* If it's a constant or doesn't have a current_def, just use the old + argument. */ if (!merge_arg) merge_arg = old_arg;
Hi, When investigating PR92317 I noticed that when we create the skip epilogue condition, see ('if (skip_epilog)' in 'vect_do_peeling'), we only copy phi-nodes that are not constants in 'slpeel_update_phi_nodes_for_guard2'. This can cause problems later when we create the scalar epilogue for this epilogue, since if the 'scalar_loop' is not the same as 'loop' 'slpeel_tree_duplicate_loop_to_edge_cfg' will expect both to have identical single_exit bb's and use that to copy the current_def meta_data of phi-nodes. This makes sure that is true even if these phi-nodes are constants, fixing PR92317. I copied the failing testcase and added the options that originally made it fail. Is this OK for trunk? Cheers, Andre gcc/ChangeLog: 2019-11-06 Andre Vieira <andre.simoesdiasvieira@arm.com> * tree-vect-loop-manip.c (slpeel_update_phi_nodes_for_guard2): Also update phi's with constant phi arguments. gcc/testsuite/ChangeLog: 2019-11-06 Andre Vieira <andre.simoesdiasvieira@arm.com> * gcc/testsuite/g++.dg/opt/pr92317.C