From 4f751c5437988863e622fd8b3ff82ec65e281260 Mon Sep 17 00:00:00 2001 From: Martin Liska Date: Fri, 9 Jun 2017 14:54:53 +0200 Subject: [PATCH] Speed-up indirect-call instrumentation 2017-06-09 Martin Liska * tree-profile.c (gimple_gen_ic_profiler): Update comment. (gimple_gen_ic_func_profiler): Emit direct comparison of __gcov_indirect_call_callee with NULL. (gimple_gen_time_profiler): Change probability from PROB_VERY_UNLIKELY to PROB_UNLIKELY. 2017-06-09 Martin Liska * libgcov-profiler.c (__gcov_indirect_call_profiler_v2): Reset __gcov_indirect_call_callee to NULL. From-SVN: r249058 --- gcc/ChangeLog | 8 ++++++ gcc/tree-profile.c | 59 ++++++++++++++++++++++++++++----------- libgcc/ChangeLog | 5 ++++ libgcc/libgcov-profiler.c | 2 ++ 4 files changed, 58 insertions(+), 16 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index b5b16918642..b9612cf0ba8 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2017-06-09 Martin Liska + + * tree-profile.c (gimple_gen_ic_profiler): Update comment. + (gimple_gen_ic_func_profiler): Emit direct comparison + of __gcov_indirect_call_callee with NULL. + (gimple_gen_time_profiler): Change probability from + PROB_VERY_UNLIKELY to PROB_UNLIKELY. + 2017-06-09 Jan Hubicka * profile.c (edge_gcov_counts): Turn to pointer. diff --git a/gcc/tree-profile.c b/gcc/tree-profile.c index a49ec37f8bb..f5c06684402 100644 --- a/gcc/tree-profile.c +++ b/gcc/tree-profile.c @@ -388,6 +388,13 @@ gimple_gen_ic_profiler (histogram_value value, unsigned tag, unsigned base) stmt1: __gcov_indirect_call_counters = get_relevant_counter_ptr (); stmt2: tmp1 = (void *) (indirect call argument value) stmt3: __gcov_indirect_call_callee = tmp1; + + Example: + f_1 = foo; + __gcov_indirect_call_counters = &__gcov4.main[0]; + PROF_9 = f_1; + __gcov_indirect_call_callee = PROF_9; + _4 = f_1 (); */ stmt1 = gimple_build_assign (ic_gcov_type_ptr_var, ref_ptr); @@ -410,9 +417,7 @@ void gimple_gen_ic_func_profiler (void) { struct cgraph_node * c_node = cgraph_node::get (current_function_decl); - gimple_stmt_iterator gsi; gcall *stmt1; - gassign *stmt2; tree tree_uid, cur_func, void0; if (c_node->only_called_directly_p ()) @@ -420,13 +425,43 @@ gimple_gen_ic_func_profiler (void) gimple_init_gcov_profiler (); + basic_block entry = ENTRY_BLOCK_PTR_FOR_FN (cfun); + basic_block cond_bb = split_edge (single_succ_edge (entry)); + basic_block update_bb = split_edge (single_succ_edge (cond_bb)); + + edge true_edge = single_succ_edge (cond_bb); + true_edge->flags = EDGE_TRUE_VALUE; + + int probability; + if (DECL_VIRTUAL_P (current_function_decl)) + probability = PROB_VERY_LIKELY; + else + probability = PROB_UNLIKELY; + + true_edge->probability = probability; + edge e = make_edge (cond_bb, single_succ_edge (update_bb)->dest, + EDGE_FALSE_VALUE); + e->probability = REG_BR_PROB_BASE - true_edge->probability; + /* Insert code: - stmt1: __gcov_indirect_call_profiler_v2 (profile_id, - ¤t_function_decl) - */ - gsi = gsi_after_labels (split_edge (single_succ_edge - (ENTRY_BLOCK_PTR_FOR_FN (cfun)))); + if (__gcov_indirect_call_callee != NULL) + __gcov_indirect_call_profiler_v2 (profile_id, ¤t_function_decl); + + The function __gcov_indirect_call_profiler_v2 is responsible for + resetting __gcov_indirect_call_callee to NULL. */ + + gimple_stmt_iterator gsi = gsi_start_bb (cond_bb); + void0 = build_int_cst (build_pointer_type (void_type_node), 0); + + tree ref = force_gimple_operand_gsi (&gsi, ic_void_ptr_var, true, NULL_TREE, + true, GSI_SAME_STMT); + + gcond *cond = gimple_build_cond (NE_EXPR, ref, + void0, NULL, NULL); + gsi_insert_before (&gsi, cond, GSI_NEW_STMT); + + gsi = gsi_after_labels (update_bb); cur_func = force_gimple_operand_gsi (&gsi, build_addr (current_function_decl), @@ -438,13 +473,6 @@ gimple_gen_ic_func_profiler (void) stmt1 = gimple_build_call (tree_indirect_call_profiler_fn, 2, tree_uid, cur_func); gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT); - - /* Set __gcov_indirect_call_callee to 0, - so that calls from other modules won't get misattributed - to the last caller of the current callee. */ - void0 = build_int_cst (build_pointer_type (void_type_node), 0); - stmt2 = gimple_build_assign (ic_void_ptr_var, void0); - gsi_insert_before (&gsi, stmt2, GSI_SAME_STMT); } /* Output instructions as GIMPLE tree at the beginning for each function. @@ -458,11 +486,10 @@ gimple_gen_time_profiler (unsigned tag, unsigned base) basic_block entry = ENTRY_BLOCK_PTR_FOR_FN (cfun); basic_block cond_bb = split_edge (single_succ_edge (entry)); basic_block update_bb = split_edge (single_succ_edge (cond_bb)); - split_edge (single_succ_edge (update_bb)); edge true_edge = single_succ_edge (cond_bb); true_edge->flags = EDGE_TRUE_VALUE; - true_edge->probability = PROB_VERY_UNLIKELY; + true_edge->probability = PROB_UNLIKELY; edge e = make_edge (cond_bb, single_succ_edge (update_bb)->dest, EDGE_FALSE_VALUE); e->probability = REG_BR_PROB_BASE - true_edge->probability; diff --git a/libgcc/ChangeLog b/libgcc/ChangeLog index 5d531d9cea6..9a97dba918f 100644 --- a/libgcc/ChangeLog +++ b/libgcc/ChangeLog @@ -1,3 +1,8 @@ +2017-06-09 Martin Liska + + * libgcov-profiler.c (__gcov_indirect_call_profiler_v2): + Reset __gcov_indirect_call_callee to NULL. + 2017-06-08 Olivier Hainque * config/t-vxworks (LIBGCC2_INCLUDES): Add path to wrn/coreip to diff --git a/libgcc/libgcov-profiler.c b/libgcc/libgcov-profiler.c index 067d762c2af..e4570a01318 100644 --- a/libgcc/libgcov-profiler.c +++ b/libgcc/libgcov-profiler.c @@ -336,6 +336,8 @@ __gcov_indirect_call_profiler_v2 (gcov_type value, void* cur_func) || (__LIBGCC_VTABLE_USES_DESCRIPTORS__ && __gcov_indirect_call_callee && *(void **) cur_func == *(void **) __gcov_indirect_call_callee)) __gcov_one_value_profiler_body (__gcov_indirect_call_counters, value, 0); + + __gcov_indirect_call_callee = NULL; } #endif -- 2.30.2