| /* Calculate branch probabilities, and basic block execution counts. |
| Copyright (C) 1990, 1991, 1992, 1993, 1994, 1996, 1997, 1998, 1999, |
| 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc. |
| Contributed by James E. Wilson, UC Berkeley/Cygnus Support; |
| based on some ideas from Dain Samples of UC Berkeley. |
| Further mangling by Bob Manson, Cygnus Support. |
| Converted to use trees by Dale Johannesen, Apple Computer. |
| |
| This file is part of GCC. |
| |
| GCC is free software; you can redistribute it and/or modify it under |
| the terms of the GNU General Public License as published by the Free |
| Software Foundation; either version 2, or (at your option) any later |
| version. |
| |
| GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
| WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GCC; see the file COPYING. If not, write to the Free |
| Software Foundation, 59 Temple Place - Suite 330, Boston, MA |
| 02111-1307, USA. */ |
| |
| /* Generate basic block profile instrumentation and auxiliary files. |
| Profile generation is optimized, so that not all arcs in the basic |
| block graph need instrumenting. First, the BB graph is closed with |
| one entry (function start), and one exit (function exit). Any |
| ABNORMAL_EDGE cannot be instrumented (because there is no control |
| path to place the code). We close the graph by inserting fake |
| EDGE_FAKE edges to the EXIT_BLOCK, from the sources of abnormal |
| edges that do not go to the exit_block. We ignore such abnormal |
| edges. Naturally these fake edges are never directly traversed, |
| and so *cannot* be directly instrumented. Some other graph |
| massaging is done. To optimize the instrumentation we generate the |
| BB minimal span tree, only edges that are not on the span tree |
| (plus the entry point) need instrumenting. From that information |
| all other edge counts can be deduced. By construction all fake |
| edges must be on the spanning tree. We also attempt to place |
| EDGE_CRITICAL edges on the spanning tree. |
| |
| The auxiliary file generated is <dumpbase>.bbg. The format is |
| described in full in gcov-io.h. */ |
| |
| /* ??? Register allocation should use basic block execution counts to |
| give preference to the most commonly executed blocks. */ |
| |
| /* ??? Should calculate branch probabilities before instrumenting code, since |
| then we can use arc counts to help decide which arcs to instrument. */ |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "tm.h" |
| #include "rtl.h" |
| #include "flags.h" |
| #include "output.h" |
| #include "regs.h" |
| #include "expr.h" |
| #include "function.h" |
| #include "toplev.h" |
| #include "coverage.h" |
| #include "tree.h" |
| #include "tree-flow.h" |
| #include "tree-dump.h" |
| #include "tree-pass.h" |
| #include "timevar.h" |
| #include "value-prof.h" |
| |
| |
| |
| /* Do initialization work for the edge profiler. */ |
| |
| static void |
| tree_init_edge_profiler (void) |
| { |
| } |
| |
| /* Output instructions as GIMPLE trees to increment the edge |
| execution count, and insert them on E. We rely on |
| bsi_insert_on_edge to preserve the order. */ |
| |
| static void |
| tree_gen_edge_profiler (int edgeno, edge e) |
| { |
| tree tmp1 = create_tmp_var (GCOV_TYPE_NODE, "PROF"); |
| tree tmp2 = create_tmp_var (GCOV_TYPE_NODE, "PROF"); |
| tree ref = tree_coverage_counter_ref (GCOV_COUNTER_ARCS, edgeno); |
| tree stmt1 = build (MODIFY_EXPR, GCOV_TYPE_NODE, tmp1, ref); |
| tree stmt2 = build (MODIFY_EXPR, GCOV_TYPE_NODE, tmp2, |
| build (PLUS_EXPR, GCOV_TYPE_NODE, |
| tmp1, integer_one_node)); |
| tree stmt3 = build (MODIFY_EXPR, GCOV_TYPE_NODE, ref, tmp2); |
| bsi_insert_on_edge (e, stmt1); |
| bsi_insert_on_edge (e, stmt2); |
| bsi_insert_on_edge (e, stmt3); |
| } |
| |
| /* Output instructions as GIMPLE trees to increment the interval histogram |
| counter. VALUE is the expression whose value is profiled. TAG is the |
| tag of the section for counters, BASE is offset of the counter position. */ |
| |
| static void |
| tree_gen_interval_profiler (histogram_value value ATTRIBUTE_UNUSED, |
| unsigned tag ATTRIBUTE_UNUSED, |
| unsigned base ATTRIBUTE_UNUSED) |
| { |
| /* FIXME implement this. */ |
| #ifdef ENABLE_CHECKING |
| internal_error ("unimplemented functionality"); |
| #endif |
| gcc_unreachable (); |
| } |
| |
| /* Output instructions as GIMPLE trees to increment the power of two histogram |
| counter. VALUE is the expression whose value is profiled. TAG is the tag |
| of the section for counters, BASE is offset of the counter position. */ |
| |
| static void |
| tree_gen_pow2_profiler (histogram_value value ATTRIBUTE_UNUSED, |
| unsigned tag ATTRIBUTE_UNUSED, |
| unsigned base ATTRIBUTE_UNUSED) |
| { |
| /* FIXME implement this. */ |
| #ifdef ENABLE_CHECKING |
| internal_error ("unimplemented functionality"); |
| #endif |
| gcc_unreachable (); |
| } |
| |
| /* Output instructions as GIMPLE trees for code to find the most common value. |
| VALUE is the expression whose value is profiled. TAG is the tag of the |
| section for counters, BASE is offset of the counter position. */ |
| |
| static void |
| tree_gen_one_value_profiler (histogram_value value ATTRIBUTE_UNUSED, |
| unsigned tag ATTRIBUTE_UNUSED, |
| unsigned base ATTRIBUTE_UNUSED) |
| { |
| /* FIXME implement this. */ |
| #ifdef ENABLE_CHECKING |
| internal_error ("unimplemented functionality"); |
| #endif |
| gcc_unreachable (); |
| } |
| |
| /* Output instructions as GIMPLE trees for code to find the most common value |
| of a difference between two evaluations of an expression. |
| VALUE is the expression whose value is profiled. TAG is the tag of the |
| section for counters, BASE is offset of the counter position. */ |
| |
| static void |
| tree_gen_const_delta_profiler (histogram_value value ATTRIBUTE_UNUSED, |
| unsigned tag ATTRIBUTE_UNUSED, |
| unsigned base ATTRIBUTE_UNUSED) |
| { |
| /* FIXME implement this. */ |
| #ifdef ENABLE_CHECKING |
| internal_error ("unimplemented functionality"); |
| #endif |
| gcc_unreachable (); |
| } |
| |
| /* Return 1 if tree-based profiling is in effect, else 0. |
| If it is, set up hooks for tree-based profiling. |
| Gate for pass_tree_profile. */ |
| |
| static bool do_tree_profiling (void) |
| { |
| if (flag_tree_based_profiling |
| && (profile_arc_flag || flag_test_coverage || flag_branch_probabilities)) |
| { |
| tree_register_profile_hooks (); |
| tree_register_value_prof_hooks (); |
| return true; |
| } |
| return false; |
| } |
| |
| /* Return the file on which profile dump output goes, if any. */ |
| |
| static FILE *tree_profile_dump_file (void) { |
| return dump_file; |
| } |
| |
| struct tree_opt_pass pass_tree_profile = |
| { |
| "tree_profile", /* name */ |
| do_tree_profiling, /* gate */ |
| branch_prob, /* execute */ |
| NULL, /* sub */ |
| NULL, /* next */ |
| 0, /* static_pass_number */ |
| TV_BRANCH_PROB, /* tv_id */ |
| PROP_gimple_leh | PROP_cfg, /* properties_required */ |
| PROP_gimple_leh | PROP_cfg, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| TODO_verify_stmts, /* todo_flags_finish */ |
| 0 /* letter */ |
| }; |
| |
| struct profile_hooks tree_profile_hooks = |
| { |
| tree_init_edge_profiler, /* init_edge_profiler */ |
| tree_gen_edge_profiler, /* gen_edge_profiler */ |
| tree_gen_interval_profiler, /* gen_interval_profiler */ |
| tree_gen_pow2_profiler, /* gen_pow2_profiler */ |
| tree_gen_one_value_profiler, /* gen_one_value_profiler */ |
| tree_gen_const_delta_profiler,/* gen_const_delta_profiler */ |
| tree_profile_dump_file /* profile_dump_file */ |
| }; |