/* Transformations based on profile information for values. Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Free Software Foundation, Inc. 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 3, 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 COPYING3. If not see . */ #include "config.h" #include "system.h" #include "coretypes.h" #include "tm.h" #include "rtl.h" #include "expr.h" #include "hard-reg-set.h" #include "basic-block.h" #include "value-prof.h" #include "flags.h" #include "insn-config.h" #include "recog.h" #include "optabs.h" #include "regs.h" #include "ggc.h" #include "tree-flow.h" #include "tree-flow-inline.h" #include "diagnostic.h" #include "gimple-pretty-print.h" #include "coverage.h" #include "tree.h" #include "gcov-io.h" #include "cgraph.h" #include "timevar.h" #include "dumpfile.h" #include "pointer-set.h" #include "profile.h" /* In this file value profile based optimizations are placed. Currently the following optimizations are implemented (for more detailed descriptions see comments at value_profile_transformations): 1) Division/modulo specialization. Provided that we can determine that the operands of the division have some special properties, we may use it to produce more effective code. 2) Indirect/virtual call specialization. If we can determine most common function callee in indirect/virtual call. We can use this information to improve code effectiveness (especially info for the inliner). 3) Speculative prefetching. If we are able to determine that the difference between addresses accessed by a memory reference is usually constant, we may add the prefetch instructions. FIXME: This transformation was removed together with RTL based value profiling. Value profiling internals ========================== Every value profiling transformation starts with defining what values to profile. There are different histogram types (see HIST_TYPE_* in value-prof.h) and each transformation can request one or more histogram types per GIMPLE statement. The function gimple_find_values_to_profile() collects the values to profile in a VEC, and adds the number of counters required for the different histogram types. For a -fprofile-generate run, the statements for which values should be recorded, are instrumented in instrument_values(). The instrumentation is done by helper functions that can be found in tree-profile.c, where new types of histograms can be added if necessary. After a -fprofile-use, the value profiling data is read back in by compute_value_histograms() that translates the collected data to histograms and attaches them to the profiled statements via gimple_add_histogram_value(). Histograms are stored in a hash table that is attached to every intrumented function, see VALUE_HISTOGRAMS in function.h. The value-profile transformations driver is the function gimple_value_profile_transformations(). It traverses all statements in the to-be-transformed function, and looks for statements with one or more histograms attached to it. If a statement has histograms, the transformation functions are called on the statement. Limitations / FIXME / TODO: * Only one histogram of each type can be associated with a statement. * Currently, HIST_TYPE_CONST_DELTA is not implemented. (This type of histogram was originally used to implement a form of stride profiling based speculative prefetching to improve SPEC2000 scores for memory-bound benchmarks, mcf and equake. However, this was an RTL value-profiling transformation, and those have all been removed.) * Some value profile transformations are done in builtins.c (?!) * Updating of histograms needs some TLC. * The value profiling code could be used to record analysis results from non-profiling (e.g. VRP). * Adding new profilers should be simplified, starting with a cleanup of what-happens-where andwith making gimple_find_values_to_profile and gimple_value_profile_transformations table-driven, perhaps... */ static tree gimple_divmod_fixed_value (gimple, tree, int, gcov_type, gcov_type); static tree gimple_mod_pow2 (gimple, int, gcov_type, gcov_type); static tree gimple_mod_subtract (gimple, int, int, int, gcov_type, gcov_type, gcov_type); static bool gimple_divmod_fixed_value_transform (gimple_stmt_iterator *); static bool gimple_mod_pow2_value_transform (gimple_stmt_iterator *); static bool gimple_mod_subtract_transform (gimple_stmt_iterator *); static bool gimple_stringops_transform (gimple_stmt_iterator *); static bool gimple_ic_transform (gimple_stmt_iterator *); /* Allocate histogram value. */ static histogram_value gimple_alloc_histogram_value (struct function *fun ATTRIBUTE_UNUSED, enum hist_type type, gimple stmt, tree value) { histogram_value hist = (histogram_value) xcalloc (1, sizeof (*hist)); hist->hvalue.value = value; hist->hvalue.stmt = stmt; hist->type = type; return hist; } /* Hash value for histogram. */ static hashval_t histogram_hash (const void *x) { return htab_hash_pointer (((const_histogram_value)x)->hvalue.stmt); } /* Return nonzero if statement for histogram_value X is Y. */ static int histogram_eq (const void *x, const void *y) { return ((const_histogram_value) x)->hvalue.stmt == (const_gimple) y; } /* Set histogram for STMT. */ static void set_histogram_value (struct function *fun, gimple stmt, histogram_value hist) { void **loc; if (!hist && !VALUE_HISTOGRAMS (fun)) return; if (!VALUE_HISTOGRAMS (fun)) VALUE_HISTOGRAMS (fun) = htab_create (1, histogram_hash, histogram_eq, NULL); loc = htab_find_slot_with_hash (VALUE_HISTOGRAMS (fun), stmt, htab_hash_pointer (stmt), hist ? INSERT : NO_INSERT); if (!hist) { if (loc) htab_clear_slot (VALUE_HISTOGRAMS (fun), loc); return; } *loc = hist; } /* Get histogram list for STMT. */ histogram_value gimple_histogram_value (struct function *fun, gimple stmt) { if (!VALUE_HISTOGRAMS (fun)) return NULL; return (histogram_value) htab_find_with_hash (VALUE_HISTOGRAMS (fun), stmt, htab_hash_pointer (stmt)); } /* Add histogram for STMT. */ void gimple_add_histogram_value (struct function *fun, gimple stmt, histogram_value hist) { hist->hvalue.next = gimple_histogram_value (fun, stmt); set_histogram_value (fun, stmt, hist); } /* Remove histogram HIST from STMT's histogram list. */ void gimple_remove_histogram_value (struct function *fun, gimple stmt, histogram_value hist) { histogram_value hist2 = gimple_histogram_value (fun, stmt); if (hist == hist2) { set_histogram_value (fun, stmt, hist->hvalue.next); } else { while (hist2->hvalue.next != hist) hist2 = hist2->hvalue.next; hist2->hvalue.next = hist->hvalue.next; } free (hist->hvalue.counters); #ifdef ENABLE_CHECKING memset (hist, 0xab, sizeof (*hist)); #endif free (hist); } /* Lookup histogram of type TYPE in the STMT. */ histogram_value gimple_histogram_value_of_type (struct function *fun, gimple stmt, enum hist_type type) { histogram_value hist; for (hist = gimple_histogram_value (fun, stmt); hist; hist = hist->hvalue.next) if (hist->type == type) return hist; return NULL; } /* Dump information about HIST to DUMP_FILE. */ static void dump_histogram_value (FILE *dump_file, histogram_value hist) { switch (hist->type) { case HIST_TYPE_INTERVAL: fprintf (dump_file, "Interval counter range %d -- %d", hist->hdata.intvl.int_start, (hist->hdata.intvl.int_start + hist->hdata.intvl.steps - 1)); if (hist->hvalue.counters) { unsigned int i; fprintf(dump_file, " ["); for (i = 0; i < hist->hdata.intvl.steps; i++) fprintf (dump_file, " %d:"HOST_WIDEST_INT_PRINT_DEC, hist->hdata.intvl.int_start + i, (HOST_WIDEST_INT) hist->hvalue.counters[i]); fprintf (dump_file, " ] outside range:"HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) hist->hvalue.counters[i]); } fprintf (dump_file, ".\n"); break; case HIST_TYPE_POW2: fprintf (dump_file, "Pow2 counter "); if (hist->hvalue.counters) { fprintf (dump_file, "pow2:"HOST_WIDEST_INT_PRINT_DEC " nonpow2:"HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) hist->hvalue.counters[0], (HOST_WIDEST_INT) hist->hvalue.counters[1]); } fprintf (dump_file, ".\n"); break; case HIST_TYPE_SINGLE_VALUE: fprintf (dump_file, "Single value "); if (hist->hvalue.counters) { fprintf (dump_file, "value:"HOST_WIDEST_INT_PRINT_DEC " match:"HOST_WIDEST_INT_PRINT_DEC " wrong:"HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) hist->hvalue.counters[0], (HOST_WIDEST_INT) hist->hvalue.counters[1], (HOST_WIDEST_INT) hist->hvalue.counters[2]); } fprintf (dump_file, ".\n"); break; case HIST_TYPE_AVERAGE: fprintf (dump_file, "Average value "); if (hist->hvalue.counters) { fprintf (dump_file, "sum:"HOST_WIDEST_INT_PRINT_DEC " times:"HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) hist->hvalue.counters[0], (HOST_WIDEST_INT) hist->hvalue.counters[1]); } fprintf (dump_file, ".\n"); break; case HIST_TYPE_IOR: fprintf (dump_file, "IOR value "); if (hist->hvalue.counters) { fprintf (dump_file, "ior:"HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) hist->hvalue.counters[0]); } fprintf (dump_file, ".\n"); break; case HIST_TYPE_CONST_DELTA: fprintf (dump_file, "Constant delta "); if (hist->hvalue.counters) { fprintf (dump_file, "value:"HOST_WIDEST_INT_PRINT_DEC " match:"HOST_WIDEST_INT_PRINT_DEC " wrong:"HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) hist->hvalue.counters[0], (HOST_WIDEST_INT) hist->hvalue.counters[1], (HOST_WIDEST_INT) hist->hvalue.counters[2]); } fprintf (dump_file, ".\n"); break; case HIST_TYPE_INDIR_CALL: fprintf (dump_file, "Indirect call "); if (hist->hvalue.counters) { fprintf (dump_file, "value:"HOST_WIDEST_INT_PRINT_DEC " match:"HOST_WIDEST_INT_PRINT_DEC " all:"HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) hist->hvalue.counters[0], (HOST_WIDEST_INT) hist->hvalue.counters[1], (HOST_WIDEST_INT) hist->hvalue.counters[2]); } fprintf (dump_file, ".\n"); break; } } /* Dump all histograms attached to STMT to DUMP_FILE. */ void dump_histograms_for_stmt (struct function *fun, FILE *dump_file, gimple stmt) { histogram_value hist; for (hist = gimple_histogram_value (fun, stmt); hist; hist = hist->hvalue.next) dump_histogram_value (dump_file, hist); } /* Remove all histograms associated with STMT. */ void gimple_remove_stmt_histograms (struct function *fun, gimple stmt) { histogram_value val; while ((val = gimple_histogram_value (fun, stmt)) != NULL) gimple_remove_histogram_value (fun, stmt, val); } /* Duplicate all histograms associates with OSTMT to STMT. */ void gimple_duplicate_stmt_histograms (struct function *fun, gimple stmt, struct function *ofun, gimple ostmt) { histogram_value val; for (val = gimple_histogram_value (ofun, ostmt); val != NULL; val = val->hvalue.next) { histogram_value new_val = gimple_alloc_histogram_value (fun, val->type, NULL, NULL); memcpy (new_val, val, sizeof (*val)); new_val->hvalue.stmt = stmt; new_val->hvalue.counters = XNEWVAR (gcov_type, sizeof (*new_val->hvalue.counters) * new_val->n_counters); memcpy (new_val->hvalue.counters, val->hvalue.counters, sizeof (*new_val->hvalue.counters) * new_val->n_counters); gimple_add_histogram_value (fun, stmt, new_val); } } /* Move all histograms associated with OSTMT to STMT. */ void gimple_move_stmt_histograms (struct function *fun, gimple stmt, gimple ostmt) { histogram_value val = gimple_histogram_value (fun, ostmt); if (val) { /* The following three statements can't be reordered, because histogram hashtab relies on stmt field value for finding the exact slot. */ set_histogram_value (fun, ostmt, NULL); for (; val != NULL; val = val->hvalue.next) val->hvalue.stmt = stmt; set_histogram_value (fun, stmt, val); } } static bool error_found = false; /* Helper function for verify_histograms. For each histogram reachable via htab walk verify that it was reached via statement walk. */ static int visit_hist (void **slot, void *data) { struct pointer_set_t *visited = (struct pointer_set_t *) data; histogram_value hist = *(histogram_value *) slot; if (!pointer_set_contains (visited, hist)) { error ("dead histogram"); dump_histogram_value (stderr, hist); debug_gimple_stmt (hist->hvalue.stmt); error_found = true; } return 1; } /* Verify sanity of the histograms. */ DEBUG_FUNCTION void verify_histograms (void) { basic_block bb; gimple_stmt_iterator gsi; histogram_value hist; struct pointer_set_t *visited_hists; error_found = false; visited_hists = pointer_set_create (); FOR_EACH_BB (bb) for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) { gimple stmt = gsi_stmt (gsi); for (hist = gimple_histogram_value (cfun, stmt); hist; hist = hist->hvalue.next) { if (hist->hvalue.stmt != stmt) { error ("Histogram value statement does not correspond to " "the statement it is associated with"); debug_gimple_stmt (stmt); dump_histogram_value (stderr, hist); error_found = true; } pointer_set_insert (visited_hists, hist); } } if (VALUE_HISTOGRAMS (cfun)) htab_traverse (VALUE_HISTOGRAMS (cfun), visit_hist, visited_hists); pointer_set_destroy (visited_hists); if (error_found) internal_error ("verify_histograms failed"); } /* Helper function for verify_histograms. For each histogram reachable via htab walk verify that it was reached via statement walk. */ static int free_hist (void **slot, void *data ATTRIBUTE_UNUSED) { histogram_value hist = *(histogram_value *) slot; free (hist->hvalue.counters); #ifdef ENABLE_CHECKING memset (hist, 0xab, sizeof (*hist)); #endif free (hist); return 1; } void free_histograms (void) { if (VALUE_HISTOGRAMS (cfun)) { htab_traverse (VALUE_HISTOGRAMS (cfun), free_hist, NULL); htab_delete (VALUE_HISTOGRAMS (cfun)); VALUE_HISTOGRAMS (cfun) = NULL; } } /* The overall number of invocations of the counter should match execution count of basic block. Report it as error rather than internal error as it might mean that user has misused the profile somehow. */ static bool check_counter (gimple stmt, const char * name, gcov_type *count, gcov_type *all, gcov_type bb_count) { if (*all != bb_count || *count > *all) { location_t locus; locus = (stmt != NULL) ? gimple_location (stmt) : DECL_SOURCE_LOCATION (current_function_decl); if (flag_profile_correction) { inform (locus, "correcting inconsistent value profile: " "%s profiler overall count (%d) does not match BB count " "(%d)", name, (int)*all, (int)bb_count); *all = bb_count; if (*count > *all) *count = *all; return false; } else { error_at (locus, "corrupted value profile: %s " "profile counter (%d out of %d) inconsistent with " "basic-block count (%d)", name, (int) *count, (int) *all, (int) bb_count); return true; } } return false; } /* GIMPLE based transformations. */ bool gimple_value_profile_transformations (void) { basic_block bb; gimple_stmt_iterator gsi; bool changed = false; FOR_EACH_BB (bb) { for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) { gimple stmt = gsi_stmt (gsi); histogram_value th = gimple_histogram_value (cfun, stmt); if (!th) continue; if (dump_file) { fprintf (dump_file, "Trying transformations on stmt "); print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); dump_histograms_for_stmt (cfun, dump_file, stmt); } /* Transformations: */ /* The order of things in this conditional controls which transformation is used when more than one is applicable. */ /* It is expected that any code added by the transformations will be added before the current statement, and that the current statement remain valid (although possibly modified) upon return. */ if (gimple_mod_subtract_transform (&gsi) || gimple_divmod_fixed_value_transform (&gsi) || gimple_mod_pow2_value_transform (&gsi) || gimple_stringops_transform (&gsi) || gimple_ic_transform (&gsi)) { stmt = gsi_stmt (gsi); changed = true; /* Original statement may no longer be in the same block. */ if (bb != gimple_bb (stmt)) { bb = gimple_bb (stmt); gsi = gsi_for_stmt (stmt); } } } } if (changed) { counts_to_freqs (); } return changed; } /* Generate code for transformation 1 (with parent gimple assignment STMT and probability of taking the optimal path PROB, which is equivalent to COUNT/ALL within roundoff error). This generates the result into a temp and returns the temp; it does not replace or alter the original STMT. */ static tree gimple_divmod_fixed_value (gimple stmt, tree value, int prob, gcov_type count, gcov_type all) { gimple stmt1, stmt2, stmt3; tree tmp0, tmp1, tmp2, tmpv; gimple bb1end, bb2end, bb3end; basic_block bb, bb2, bb3, bb4; tree optype, op1, op2; edge e12, e13, e23, e24, e34; gimple_stmt_iterator gsi; gcc_assert (is_gimple_assign (stmt) && (gimple_assign_rhs_code (stmt) == TRUNC_DIV_EXPR || gimple_assign_rhs_code (stmt) == TRUNC_MOD_EXPR)); optype = TREE_TYPE (gimple_assign_lhs (stmt)); op1 = gimple_assign_rhs1 (stmt); op2 = gimple_assign_rhs2 (stmt); bb = gimple_bb (stmt); gsi = gsi_for_stmt (stmt); tmpv = create_tmp_reg (optype, "PROF"); tmp0 = make_ssa_name (tmpv, NULL); tmp1 = make_ssa_name (tmpv, NULL); stmt1 = gimple_build_assign (tmp0, fold_convert (optype, value)); SSA_NAME_DEF_STMT (tmp0) = stmt1; stmt2 = gimple_build_assign (tmp1, op2); SSA_NAME_DEF_STMT (tmp1) = stmt2; stmt3 = gimple_build_cond (NE_EXPR, tmp1, tmp0, NULL_TREE, NULL_TREE); gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT); gsi_insert_before (&gsi, stmt2, GSI_SAME_STMT); gsi_insert_before (&gsi, stmt3, GSI_SAME_STMT); bb1end = stmt3; tmp2 = make_rename_temp (optype, "PROF"); stmt1 = gimple_build_assign_with_ops (gimple_assign_rhs_code (stmt), tmp2, op1, tmp0); gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT); bb2end = stmt1; stmt1 = gimple_build_assign_with_ops (gimple_assign_rhs_code (stmt), tmp2, op1, op2); gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT); bb3end = stmt1; /* Fix CFG. */ /* Edge e23 connects bb2 to bb3, etc. */ e12 = split_block (bb, bb1end); bb2 = e12->dest; bb2->count = count; e23 = split_block (bb2, bb2end); bb3 = e23->dest; bb3->count = all - count; e34 = split_block (bb3, bb3end); bb4 = e34->dest; bb4->count = all; e12->flags &= ~EDGE_FALLTHRU; e12->flags |= EDGE_FALSE_VALUE; e12->probability = prob; e12->count = count; e13 = make_edge (bb, bb3, EDGE_TRUE_VALUE); e13->probability = REG_BR_PROB_BASE - prob; e13->count = all - count; remove_edge (e23); e24 = make_edge (bb2, bb4, EDGE_FALLTHRU); e24->probability = REG_BR_PROB_BASE; e24->count = count; e34->probability = REG_BR_PROB_BASE; e34->count = all - count; return tmp2; } /* Do transform 1) on INSN if applicable. */ static bool gimple_divmod_fixed_value_transform (gimple_stmt_iterator *si) { histogram_value histogram; enum tree_code code; gcov_type val, count, all; tree result, value, tree_val; gcov_type prob; gimple stmt; stmt = gsi_stmt (*si); if (gimple_code (stmt) != GIMPLE_ASSIGN) return false; if (!INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (stmt)))) return false; code = gimple_assign_rhs_code (stmt); if (code != TRUNC_DIV_EXPR && code != TRUNC_MOD_EXPR) return false; histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_SINGLE_VALUE); if (!histogram) return false; value = histogram->hvalue.value; val = histogram->hvalue.counters[0]; count = histogram->hvalue.counters[1]; all = histogram->hvalue.counters[2]; gimple_remove_histogram_value (cfun, stmt, histogram); /* We require that count is at least half of all; this means that for the transformation to fire the value must be constant at least 50% of time (and 75% gives the guarantee of usage). */ if (simple_cst_equal (gimple_assign_rhs2 (stmt), value) != 1 || 2 * count < all || optimize_bb_for_size_p (gimple_bb (stmt))) return false; if (check_counter (stmt, "value", &count, &all, gimple_bb (stmt)->count)) return false; /* Compute probability of taking the optimal path. */ if (all > 0) prob = (count * REG_BR_PROB_BASE + all / 2) / all; else prob = 0; tree_val = build_int_cst_wide (get_gcov_type (), (unsigned HOST_WIDE_INT) val, val >> (HOST_BITS_PER_WIDE_INT - 1) >> 1); result = gimple_divmod_fixed_value (stmt, tree_val, prob, count, all); if (dump_file) { fprintf (dump_file, "Div/mod by constant "); print_generic_expr (dump_file, value, TDF_SLIM); fprintf (dump_file, "="); print_generic_expr (dump_file, tree_val, TDF_SLIM); fprintf (dump_file, " transformation on insn "); print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); } gimple_assign_set_rhs_from_tree (si, result); update_stmt (gsi_stmt (*si)); return true; } /* Generate code for transformation 2 (with parent gimple assign STMT and probability of taking the optimal path PROB, which is equivalent to COUNT/ALL within roundoff error). This generates the result into a temp and returns the temp; it does not replace or alter the original STMT. */ static tree gimple_mod_pow2 (gimple stmt, int prob, gcov_type count, gcov_type all) { gimple stmt1, stmt2, stmt3, stmt4; tree tmp2, tmp3, tmpv; gimple bb1end, bb2end, bb3end; basic_block bb, bb2, bb3, bb4; tree optype, op1, op2; edge e12, e13, e23, e24, e34; gimple_stmt_iterator gsi; tree result; gcc_assert (is_gimple_assign (stmt) && gimple_assign_rhs_code (stmt) == TRUNC_MOD_EXPR); optype = TREE_TYPE (gimple_assign_lhs (stmt)); op1 = gimple_assign_rhs1 (stmt); op2 = gimple_assign_rhs2 (stmt); bb = gimple_bb (stmt); gsi = gsi_for_stmt (stmt); result = make_rename_temp (optype, "PROF"); tmpv = create_tmp_var (optype, "PROF"); tmp2 = make_ssa_name (tmpv, NULL); tmp3 = make_ssa_name (tmpv, NULL); stmt2 = gimple_build_assign_with_ops (PLUS_EXPR, tmp2, op2, build_int_cst (optype, -1)); SSA_NAME_DEF_STMT (tmp2) = stmt2; stmt3 = gimple_build_assign_with_ops (BIT_AND_EXPR, tmp3, tmp2, op2); SSA_NAME_DEF_STMT (tmp3) = stmt3; stmt4 = gimple_build_cond (NE_EXPR, tmp3, build_int_cst (optype, 0), NULL_TREE, NULL_TREE); gsi_insert_before (&gsi, stmt2, GSI_SAME_STMT); gsi_insert_before (&gsi, stmt3, GSI_SAME_STMT); gsi_insert_before (&gsi, stmt4, GSI_SAME_STMT); bb1end = stmt4; /* tmp2 == op2-1 inherited from previous block. */ stmt1 = gimple_build_assign_with_ops (BIT_AND_EXPR, result, op1, tmp2); gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT); bb2end = stmt1; stmt1 = gimple_build_assign_with_ops (gimple_assign_rhs_code (stmt), result, op1, op2); gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT); bb3end = stmt1; /* Fix CFG. */ /* Edge e23 connects bb2 to bb3, etc. */ e12 = split_block (bb, bb1end); bb2 = e12->dest; bb2->count = count; e23 = split_block (bb2, bb2end); bb3 = e23->dest; bb3->count = all - count; e34 = split_block (bb3, bb3end); bb4 = e34->dest; bb4->count = all; e12->flags &= ~EDGE_FALLTHRU; e12->flags |= EDGE_FALSE_VALUE; e12->probability = prob; e12->count = count; e13 = make_edge (bb, bb3, EDGE_TRUE_VALUE); e13->probability = REG_BR_PROB_BASE - prob; e13->count = all - count; remove_edge (e23); e24 = make_edge (bb2, bb4, EDGE_FALLTHRU); e24->probability = REG_BR_PROB_BASE; e24->count = count; e34->probability = REG_BR_PROB_BASE; e34->count = all - count; return result; } /* Do transform 2) on INSN if applicable. */ static bool gimple_mod_pow2_value_transform (gimple_stmt_iterator *si) { histogram_value histogram; enum tree_code code; gcov_type count, wrong_values, all; tree lhs_type, result, value; gcov_type prob; gimple stmt; stmt = gsi_stmt (*si); if (gimple_code (stmt) != GIMPLE_ASSIGN) return false; lhs_type = TREE_TYPE (gimple_assign_lhs (stmt)); if (!INTEGRAL_TYPE_P (lhs_type)) return false; code = gimple_assign_rhs_code (stmt); if (code != TRUNC_MOD_EXPR || !TYPE_UNSIGNED (lhs_type)) return false; histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_POW2); if (!histogram) return false; value = histogram->hvalue.value; wrong_values = histogram->hvalue.counters[0]; count = histogram->hvalue.counters[1]; gimple_remove_histogram_value (cfun, stmt, histogram); /* We require that we hit a power of 2 at least half of all evaluations. */ if (simple_cst_equal (gimple_assign_rhs2 (stmt), value) != 1 || count < wrong_values || optimize_bb_for_size_p (gimple_bb (stmt))) return false; if (dump_file) { fprintf (dump_file, "Mod power of 2 transformation on insn "); print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); } /* Compute probability of taking the optimal path. */ all = count + wrong_values; if (check_counter (stmt, "pow2", &count, &all, gimple_bb (stmt)->count)) return false; if (all > 0) prob = (count * REG_BR_PROB_BASE + all / 2) / all; else prob = 0; result = gimple_mod_pow2 (stmt, prob, count, all); gimple_assign_set_rhs_from_tree (si, result); update_stmt (gsi_stmt (*si)); return true; } /* Generate code for transformations 3 and 4 (with parent gimple assign STMT, and NCOUNTS the number of cases to support. Currently only NCOUNTS==0 or 1 is supported and this is built into this interface. The probabilities of taking the optimal paths are PROB1 and PROB2, which are equivalent to COUNT1/ALL and COUNT2/ALL respectively within roundoff error). This generates the result into a temp and returns the temp; it does not replace or alter the original STMT. */ /* FIXME: Generalize the interface to handle NCOUNTS > 1. */ static tree gimple_mod_subtract (gimple stmt, int prob1, int prob2, int ncounts, gcov_type count1, gcov_type count2, gcov_type all) { gimple stmt1, stmt2, stmt3; tree tmp1; gimple bb1end, bb2end = NULL, bb3end; basic_block bb, bb2, bb3, bb4; tree optype, op1, op2; edge e12, e23 = 0, e24, e34, e14; gimple_stmt_iterator gsi; tree result; gcc_assert (is_gimple_assign (stmt) && gimple_assign_rhs_code (stmt) == TRUNC_MOD_EXPR); optype = TREE_TYPE (gimple_assign_lhs (stmt)); op1 = gimple_assign_rhs1 (stmt); op2 = gimple_assign_rhs2 (stmt); bb = gimple_bb (stmt); gsi = gsi_for_stmt (stmt); result = make_rename_temp (optype, "PROF"); tmp1 = make_ssa_name (create_tmp_var (optype, "PROF"), NULL); stmt1 = gimple_build_assign (result, op1); stmt2 = gimple_build_assign (tmp1, op2); SSA_NAME_DEF_STMT (tmp1) = stmt2; stmt3 = gimple_build_cond (LT_EXPR, result, tmp1, NULL_TREE, NULL_TREE); gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT); gsi_insert_before (&gsi, stmt2, GSI_SAME_STMT); gsi_insert_before (&gsi, stmt3, GSI_SAME_STMT); bb1end = stmt3; if (ncounts) /* Assumed to be 0 or 1 */ { stmt1 = gimple_build_assign_with_ops (MINUS_EXPR, result, result, tmp1); stmt2 = gimple_build_cond (LT_EXPR, result, tmp1, NULL_TREE, NULL_TREE); gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT); gsi_insert_before (&gsi, stmt2, GSI_SAME_STMT); bb2end = stmt2; } /* Fallback case. */ stmt1 = gimple_build_assign_with_ops (gimple_assign_rhs_code (stmt), result, result, tmp1); gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT); bb3end = stmt1; /* Fix CFG. */ /* Edge e23 connects bb2 to bb3, etc. */ /* However block 3 is optional; if it is not there, references to 3 really refer to block 2. */ e12 = split_block (bb, bb1end); bb2 = e12->dest; bb2->count = all - count1; if (ncounts) /* Assumed to be 0 or 1. */ { e23 = split_block (bb2, bb2end); bb3 = e23->dest; bb3->count = all - count1 - count2; } e34 = split_block (ncounts ? bb3 : bb2, bb3end); bb4 = e34->dest; bb4->count = all; e12->flags &= ~EDGE_FALLTHRU; e12->flags |= EDGE_FALSE_VALUE; e12->probability = REG_BR_PROB_BASE - prob1; e12->count = all - count1; e14 = make_edge (bb, bb4, EDGE_TRUE_VALUE); e14->probability = prob1; e14->count = count1; if (ncounts) /* Assumed to be 0 or 1. */ { e23->flags &= ~EDGE_FALLTHRU; e23->flags |= EDGE_FALSE_VALUE; e23->count = all - count1 - count2; e23->probability = REG_BR_PROB_BASE - prob2; e24 = make_edge (bb2, bb4, EDGE_TRUE_VALUE); e24->probability = prob2; e24->count = count2; } e34->probability = REG_BR_PROB_BASE; e34->count = all - count1 - count2; return result; } /* Do transforms 3) and 4) on the statement pointed-to by SI if applicable. */ static bool gimple_mod_subtract_transform (gimple_stmt_iterator *si) { histogram_value histogram; enum tree_code code; gcov_type count, wrong_values, all; tree lhs_type, result; gcov_type prob1, prob2; unsigned int i, steps; gcov_type count1, count2; gimple stmt; stmt = gsi_stmt (*si); if (gimple_code (stmt) != GIMPLE_ASSIGN) return false; lhs_type = TREE_TYPE (gimple_assign_lhs (stmt)); if (!INTEGRAL_TYPE_P (lhs_type)) return false; code = gimple_assign_rhs_code (stmt); if (code != TRUNC_MOD_EXPR || !TYPE_UNSIGNED (lhs_type)) return false; histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_INTERVAL); if (!histogram) return false; all = 0; wrong_values = 0; for (i = 0; i < histogram->hdata.intvl.steps; i++) all += histogram->hvalue.counters[i]; wrong_values += histogram->hvalue.counters[i]; wrong_values += histogram->hvalue.counters[i+1]; steps = histogram->hdata.intvl.steps; all += wrong_values; count1 = histogram->hvalue.counters[0]; count2 = histogram->hvalue.counters[1]; /* Compute probability of taking the optimal path. */ if (check_counter (stmt, "interval", &count1, &all, gimple_bb (stmt)->count)) { gimple_remove_histogram_value (cfun, stmt, histogram); return false; } if (flag_profile_correction && count1 + count2 > all) all = count1 + count2; gcc_assert (count1 + count2 <= all); /* We require that we use just subtractions in at least 50% of all evaluations. */ count = 0; for (i = 0; i < histogram->hdata.intvl.steps; i++) { count += histogram->hvalue.counters[i]; if (count * 2 >= all) break; } if (i == steps || optimize_bb_for_size_p (gimple_bb (stmt))) return false; gimple_remove_histogram_value (cfun, stmt, histogram); if (dump_file) { fprintf (dump_file, "Mod subtract transformation on insn "); print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); } /* Compute probability of taking the optimal path(s). */ if (all > 0) { prob1 = (count1 * REG_BR_PROB_BASE + all / 2) / all; prob2 = (count2 * REG_BR_PROB_BASE + all / 2) / all; } else { prob1 = prob2 = 0; } /* In practice, "steps" is always 2. This interface reflects this, and will need to be changed if "steps" can change. */ result = gimple_mod_subtract (stmt, prob1, prob2, i, count1, count2, all); gimple_assign_set_rhs_from_tree (si, result); update_stmt (gsi_stmt (*si)); return true; } static VEC(cgraph_node_ptr, heap) *cgraph_node_map = NULL; /* Initialize map from FUNCDEF_NO to CGRAPH_NODE. */ void init_node_map (void) { struct cgraph_node *n; if (get_last_funcdef_no ()) VEC_safe_grow_cleared (cgraph_node_ptr, heap, cgraph_node_map, get_last_funcdef_no ()); FOR_EACH_FUNCTION (n) { if (DECL_STRUCT_FUNCTION (n->symbol.decl)) VEC_replace (cgraph_node_ptr, cgraph_node_map, DECL_STRUCT_FUNCTION (n->symbol.decl)->funcdef_no, n); } } /* Delete the CGRAPH_NODE_MAP. */ void del_node_map (void) { VEC_free (cgraph_node_ptr, heap, cgraph_node_map); cgraph_node_map = NULL; } /* Return cgraph node for function with pid */ static inline struct cgraph_node* find_func_by_funcdef_no (int func_id) { int max_id = get_last_funcdef_no (); if (func_id >= max_id || VEC_index (cgraph_node_ptr, cgraph_node_map, func_id) == NULL) { if (flag_profile_correction) inform (DECL_SOURCE_LOCATION (current_function_decl), "Inconsistent profile: indirect call target (%d) does not exist", func_id); else error ("Inconsistent profile: indirect call target (%d) does not exist", func_id); return NULL; } return VEC_index (cgraph_node_ptr, cgraph_node_map, func_id); } /* Perform sanity check on the indirect call target. Due to race conditions, false function target may be attributed to an indirect call site. If the call expression type mismatches with the target function's type, expand_call may ICE. Here we only do very minimal sanity check just to make compiler happy. Returns true if TARGET is considered ok for call CALL_STMT. */ static bool check_ic_target (gimple call_stmt, struct cgraph_node *target) { location_t locus; if (gimple_check_call_matching_types (call_stmt, target->symbol.decl)) return true; locus = gimple_location (call_stmt); inform (locus, "Skipping target %s with mismatching types for icall ", cgraph_node_name (target)); return false; } /* Do transformation if (actual_callee_address == address_of_most_common_function/method) do direct call else old call */ static gimple gimple_ic (gimple icall_stmt, struct cgraph_node *direct_call, int prob, gcov_type count, gcov_type all) { gimple dcall_stmt, load_stmt, cond_stmt; tree tmp0, tmp1, tmpv, tmp; basic_block cond_bb, dcall_bb, icall_bb, join_bb = NULL; tree optype = build_pointer_type (void_type_node); edge e_cd, e_ci, e_di, e_dj = NULL, e_ij; gimple_stmt_iterator gsi; int lp_nr, dflags; cond_bb = gimple_bb (icall_stmt); gsi = gsi_for_stmt (icall_stmt); tmpv = create_tmp_reg (optype, "PROF"); tmp0 = make_ssa_name (tmpv, NULL); tmp1 = make_ssa_name (tmpv, NULL); tmp = unshare_expr (gimple_call_fn (icall_stmt)); load_stmt = gimple_build_assign (tmp0, tmp); SSA_NAME_DEF_STMT (tmp0) = load_stmt; gsi_insert_before (&gsi, load_stmt, GSI_SAME_STMT); tmp = fold_convert (optype, build_addr (direct_call->symbol.decl, current_function_decl)); load_stmt = gimple_build_assign (tmp1, tmp); SSA_NAME_DEF_STMT (tmp1) = load_stmt; gsi_insert_before (&gsi, load_stmt, GSI_SAME_STMT); cond_stmt = gimple_build_cond (EQ_EXPR, tmp1, tmp0, NULL_TREE, NULL_TREE); gsi_insert_before (&gsi, cond_stmt, GSI_SAME_STMT); gimple_set_vdef (icall_stmt, NULL_TREE); gimple_set_vuse (icall_stmt, NULL_TREE); update_stmt (icall_stmt); dcall_stmt = gimple_copy (icall_stmt); gimple_call_set_fndecl (dcall_stmt, direct_call->symbol.decl); dflags = flags_from_decl_or_type (direct_call->symbol.decl); if ((dflags & ECF_NORETURN) != 0) gimple_call_set_lhs (dcall_stmt, NULL_TREE); gsi_insert_before (&gsi, dcall_stmt, GSI_SAME_STMT); /* Fix CFG. */ /* Edge e_cd connects cond_bb to dcall_bb, etc; note the first letters. */ e_cd = split_block (cond_bb, cond_stmt); dcall_bb = e_cd->dest; dcall_bb->count = count; e_di = split_block (dcall_bb, dcall_stmt); icall_bb = e_di->dest; icall_bb->count = all - count; /* Do not disturb existing EH edges from the indirect call. */ if (!stmt_ends_bb_p (icall_stmt)) e_ij = split_block (icall_bb, icall_stmt); else { e_ij = find_fallthru_edge (icall_bb->succs); /* The indirect call might be noreturn. */ if (e_ij != NULL) { e_ij->probability = REG_BR_PROB_BASE; e_ij->count = all - count; e_ij = single_pred_edge (split_edge (e_ij)); } } if (e_ij != NULL) { join_bb = e_ij->dest; join_bb->count = all; } e_cd->flags = (e_cd->flags & ~EDGE_FALLTHRU) | EDGE_TRUE_VALUE; e_cd->probability = prob; e_cd->count = count; e_ci = make_edge (cond_bb, icall_bb, EDGE_FALSE_VALUE); e_ci->probability = REG_BR_PROB_BASE - prob; e_ci->count = all - count; remove_edge (e_di); if (e_ij != NULL) { if ((dflags & ECF_NORETURN) != 0) e_ij->count = all; else { e_dj = make_edge (dcall_bb, join_bb, EDGE_FALLTHRU); e_dj->probability = REG_BR_PROB_BASE; e_dj->count = count; e_ij->count = all - count; } e_ij->probability = REG_BR_PROB_BASE; } /* Insert PHI node for the call result if necessary. */ if (gimple_call_lhs (icall_stmt) && TREE_CODE (gimple_call_lhs (icall_stmt)) == SSA_NAME && (dflags & ECF_NORETURN) == 0) { tree result = gimple_call_lhs (icall_stmt); gimple phi = create_phi_node (result, join_bb); SSA_NAME_DEF_STMT (result) = phi; gimple_call_set_lhs (icall_stmt, make_ssa_name (SSA_NAME_VAR (result), icall_stmt)); add_phi_arg (phi, gimple_call_lhs (icall_stmt), e_ij, UNKNOWN_LOCATION); gimple_call_set_lhs (dcall_stmt, make_ssa_name (SSA_NAME_VAR (result), dcall_stmt)); add_phi_arg (phi, gimple_call_lhs (dcall_stmt), e_dj, UNKNOWN_LOCATION); } /* Build an EH edge for the direct call if necessary. */ lp_nr = lookup_stmt_eh_lp (icall_stmt); if (lp_nr != 0 && stmt_could_throw_p (dcall_stmt)) { edge e_eh, e; edge_iterator ei; gimple_stmt_iterator psi; add_stmt_to_eh_lp (dcall_stmt, lp_nr); FOR_EACH_EDGE (e_eh, ei, icall_bb->succs) if (e_eh->flags & EDGE_EH) break; e = make_edge (dcall_bb, e_eh->dest, EDGE_EH); for (psi = gsi_start_phis (e_eh->dest); !gsi_end_p (psi); gsi_next (&psi)) { gimple phi = gsi_stmt (psi); SET_USE (PHI_ARG_DEF_PTR_FROM_EDGE (phi, e), PHI_ARG_DEF_FROM_EDGE (phi, e_eh)); } } return dcall_stmt; } /* For every checked indirect/virtual call determine if most common pid of function/class method has probability more than 50%. If yes modify code of this call to: */ static bool gimple_ic_transform (gimple_stmt_iterator *gsi) { gimple stmt = gsi_stmt (*gsi); histogram_value histogram; gcov_type val, count, all, bb_all; gcov_type prob; gimple modify; struct cgraph_node *direct_call; if (gimple_code (stmt) != GIMPLE_CALL) return false; if (gimple_call_fndecl (stmt) != NULL_TREE) return false; if (gimple_call_internal_p (stmt)) return false; histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_INDIR_CALL); if (!histogram) return false; val = histogram->hvalue.counters [0]; count = histogram->hvalue.counters [1]; all = histogram->hvalue.counters [2]; gimple_remove_histogram_value (cfun, stmt, histogram); if (4 * count <= 3 * all) return false; bb_all = gimple_bb (stmt)->count; /* The order of CHECK_COUNTER calls is important - since check_counter can correct the third parameter and we want to make count <= all <= bb_all. */ if ( check_counter (stmt, "ic", &all, &bb_all, bb_all) || check_counter (stmt, "ic", &count, &all, all)) return false; if (all > 0) prob = (count * REG_BR_PROB_BASE + all / 2) / all; else prob = 0; direct_call = find_func_by_funcdef_no ((int)val); if (direct_call == NULL) return false; if (!check_ic_target (stmt, direct_call)) return false; modify = gimple_ic (stmt, direct_call, prob, count, all); if (dump_file) { fprintf (dump_file, "Indirect call -> direct call "); print_generic_expr (dump_file, gimple_call_fn (stmt), TDF_SLIM); fprintf (dump_file, "=> "); print_generic_expr (dump_file, direct_call->symbol.decl, TDF_SLIM); fprintf (dump_file, " transformation on insn "); print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); fprintf (dump_file, " to "); print_gimple_stmt (dump_file, modify, 0, TDF_SLIM); fprintf (dump_file, "hist->count "HOST_WIDEST_INT_PRINT_DEC " hist->all "HOST_WIDEST_INT_PRINT_DEC"\n", count, all); } return true; } /* Return true if the stringop CALL with FNDECL shall be profiled. SIZE_ARG be set to the argument index for the size of the string operation. */ static bool interesting_stringop_to_profile_p (tree fndecl, gimple call, int *size_arg) { enum built_in_function fcode = DECL_FUNCTION_CODE (fndecl); if (fcode != BUILT_IN_MEMCPY && fcode != BUILT_IN_MEMPCPY && fcode != BUILT_IN_MEMSET && fcode != BUILT_IN_BZERO) return false; switch (fcode) { case BUILT_IN_MEMCPY: case BUILT_IN_MEMPCPY: *size_arg = 2; return validate_gimple_arglist (call, POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE); case BUILT_IN_MEMSET: *size_arg = 2; return validate_gimple_arglist (call, POINTER_TYPE, INTEGER_TYPE, INTEGER_TYPE, VOID_TYPE); case BUILT_IN_BZERO: *size_arg = 1; return validate_gimple_arglist (call, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE); default: gcc_unreachable (); } } /* Convert stringop (..., vcall_size) into if (vcall_size == icall_size) stringop (..., icall_size); else stringop (..., vcall_size); assuming we'll propagate a true constant into ICALL_SIZE later. */ static void gimple_stringop_fixed_value (gimple vcall_stmt, tree icall_size, int prob, gcov_type count, gcov_type all) { gimple tmp_stmt, cond_stmt, icall_stmt; tree tmp0, tmp1, tmpv, vcall_size, optype; basic_block cond_bb, icall_bb, vcall_bb, join_bb; edge e_ci, e_cv, e_iv, e_ij, e_vj; gimple_stmt_iterator gsi; tree fndecl; int size_arg; fndecl = gimple_call_fndecl (vcall_stmt); if (!interesting_stringop_to_profile_p (fndecl, vcall_stmt, &size_arg)) gcc_unreachable(); cond_bb = gimple_bb (vcall_stmt); gsi = gsi_for_stmt (vcall_stmt); vcall_size = gimple_call_arg (vcall_stmt, size_arg); optype = TREE_TYPE (vcall_size); tmpv = create_tmp_var (optype, "PROF"); tmp0 = make_ssa_name (tmpv, NULL); tmp1 = make_ssa_name (tmpv, NULL); tmp_stmt = gimple_build_assign (tmp0, fold_convert (optype, icall_size)); SSA_NAME_DEF_STMT (tmp0) = tmp_stmt; gsi_insert_before (&gsi, tmp_stmt, GSI_SAME_STMT); tmp_stmt = gimple_build_assign (tmp1, vcall_size); SSA_NAME_DEF_STMT (tmp1) = tmp_stmt; gsi_insert_before (&gsi, tmp_stmt, GSI_SAME_STMT); cond_stmt = gimple_build_cond (EQ_EXPR, tmp1, tmp0, NULL_TREE, NULL_TREE); gsi_insert_before (&gsi, cond_stmt, GSI_SAME_STMT); gimple_set_vdef (vcall_stmt, NULL); gimple_set_vuse (vcall_stmt, NULL); update_stmt (vcall_stmt); icall_stmt = gimple_copy (vcall_stmt); gimple_call_set_arg (icall_stmt, size_arg, icall_size); gsi_insert_before (&gsi, icall_stmt, GSI_SAME_STMT); /* Fix CFG. */ /* Edge e_ci connects cond_bb to icall_bb, etc. */ e_ci = split_block (cond_bb, cond_stmt); icall_bb = e_ci->dest; icall_bb->count = count; e_iv = split_block (icall_bb, icall_stmt); vcall_bb = e_iv->dest; vcall_bb->count = all - count; e_vj = split_block (vcall_bb, vcall_stmt); join_bb = e_vj->dest; join_bb->count = all; e_ci->flags = (e_ci->flags & ~EDGE_FALLTHRU) | EDGE_TRUE_VALUE; e_ci->probability = prob; e_ci->count = count; e_cv = make_edge (cond_bb, vcall_bb, EDGE_FALSE_VALUE); e_cv->probability = REG_BR_PROB_BASE - prob; e_cv->count = all - count; remove_edge (e_iv); e_ij = make_edge (icall_bb, join_bb, EDGE_FALLTHRU); e_ij->probability = REG_BR_PROB_BASE; e_ij->count = count; e_vj->probability = REG_BR_PROB_BASE; e_vj->count = all - count; /* Insert PHI node for the call result if necessary. */ if (gimple_call_lhs (vcall_stmt) && TREE_CODE (gimple_call_lhs (vcall_stmt)) == SSA_NAME) { tree result = gimple_call_lhs (vcall_stmt); gimple phi = create_phi_node (result, join_bb); SSA_NAME_DEF_STMT (result) = phi; gimple_call_set_lhs (vcall_stmt, make_ssa_name (SSA_NAME_VAR (result), vcall_stmt)); add_phi_arg (phi, gimple_call_lhs (vcall_stmt), e_vj, UNKNOWN_LOCATION); gimple_call_set_lhs (icall_stmt, make_ssa_name (SSA_NAME_VAR (result), icall_stmt)); add_phi_arg (phi, gimple_call_lhs (icall_stmt), e_ij, UNKNOWN_LOCATION); } /* Because these are all string op builtins, they're all nothrow. */ gcc_assert (!stmt_could_throw_p (vcall_stmt)); gcc_assert (!stmt_could_throw_p (icall_stmt)); } /* Find values inside STMT for that we want to measure histograms for division/modulo optimization. */ static bool gimple_stringops_transform (gimple_stmt_iterator *gsi) { gimple stmt = gsi_stmt (*gsi); tree fndecl; tree blck_size; enum built_in_function fcode; histogram_value histogram; gcov_type count, all, val; tree dest, src; unsigned int dest_align, src_align; gcov_type prob; tree tree_val; int size_arg; if (gimple_code (stmt) != GIMPLE_CALL) return false; fndecl = gimple_call_fndecl (stmt); if (!fndecl) return false; fcode = DECL_FUNCTION_CODE (fndecl); if (!interesting_stringop_to_profile_p (fndecl, stmt, &size_arg)) return false; blck_size = gimple_call_arg (stmt, size_arg); if (TREE_CODE (blck_size) == INTEGER_CST) return false; histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_SINGLE_VALUE); if (!histogram) return false; val = histogram->hvalue.counters[0]; count = histogram->hvalue.counters[1]; all = histogram->hvalue.counters[2]; gimple_remove_histogram_value (cfun, stmt, histogram); /* We require that count is at least half of all; this means that for the transformation to fire the value must be constant at least 80% of time. */ if ((6 * count / 5) < all || optimize_bb_for_size_p (gimple_bb (stmt))) return false; if (check_counter (stmt, "value", &count, &all, gimple_bb (stmt)->count)) return false; if (all > 0) prob = (count * REG_BR_PROB_BASE + all / 2) / all; else prob = 0; dest = gimple_call_arg (stmt, 0); dest_align = get_pointer_alignment (dest); switch (fcode) { case BUILT_IN_MEMCPY: case BUILT_IN_MEMPCPY: src = gimple_call_arg (stmt, 1); src_align = get_pointer_alignment (src); if (!can_move_by_pieces (val, MIN (dest_align, src_align))) return false; break; case BUILT_IN_MEMSET: if (!can_store_by_pieces (val, builtin_memset_read_str, gimple_call_arg (stmt, 1), dest_align, true)) return false; break; case BUILT_IN_BZERO: if (!can_store_by_pieces (val, builtin_memset_read_str, integer_zero_node, dest_align, true)) return false; break; default: gcc_unreachable (); } tree_val = build_int_cst_wide (get_gcov_type (), (unsigned HOST_WIDE_INT) val, val >> (HOST_BITS_PER_WIDE_INT - 1) >> 1); if (dump_file) { fprintf (dump_file, "Single value %i stringop transformation on ", (int)val); print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); } gimple_stringop_fixed_value (stmt, tree_val, prob, count, all); return true; } void stringop_block_profile (gimple stmt, unsigned int *expected_align, HOST_WIDE_INT *expected_size) { histogram_value histogram; histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_AVERAGE); if (!histogram) *expected_size = -1; else if (!histogram->hvalue.counters[1]) { *expected_size = -1; gimple_remove_histogram_value (cfun, stmt, histogram); } else { gcov_type size; size = ((histogram->hvalue.counters[0] + histogram->hvalue.counters[1] / 2) / histogram->hvalue.counters[1]); /* Even if we can hold bigger value in SIZE, INT_MAX is safe "infinity" for code generation strategies. */ if (size > INT_MAX) size = INT_MAX; *expected_size = size; gimple_remove_histogram_value (cfun, stmt, histogram); } histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_IOR); if (!histogram) *expected_align = 0; else if (!histogram->hvalue.counters[0]) { gimple_remove_histogram_value (cfun, stmt, histogram); *expected_align = 0; } else { gcov_type count; int alignment; count = histogram->hvalue.counters[0]; alignment = 1; while (!(count & alignment) && (alignment * 2 * BITS_PER_UNIT)) alignment <<= 1; *expected_align = alignment * BITS_PER_UNIT; gimple_remove_histogram_value (cfun, stmt, histogram); } } /* Find values inside STMT for that we want to measure histograms for division/modulo optimization. */ static void gimple_divmod_values_to_profile (gimple stmt, histogram_values *values) { tree lhs, divisor, op0, type; histogram_value hist; if (gimple_code (stmt) != GIMPLE_ASSIGN) return; lhs = gimple_assign_lhs (stmt); type = TREE_TYPE (lhs); if (!INTEGRAL_TYPE_P (type)) return; switch (gimple_assign_rhs_code (stmt)) { case TRUNC_DIV_EXPR: case TRUNC_MOD_EXPR: divisor = gimple_assign_rhs2 (stmt); op0 = gimple_assign_rhs1 (stmt); VEC_reserve (histogram_value, heap, *values, 3); if (is_gimple_reg (divisor)) /* Check for the case where the divisor is the same value most of the time. */ VEC_quick_push (histogram_value, *values, gimple_alloc_histogram_value (cfun, HIST_TYPE_SINGLE_VALUE, stmt, divisor)); /* For mod, check whether it is not often a noop (or replaceable by a few subtractions). */ if (gimple_assign_rhs_code (stmt) == TRUNC_MOD_EXPR && TYPE_UNSIGNED (type)) { tree val; /* Check for a special case where the divisor is power of 2. */ VEC_quick_push (histogram_value, *values, gimple_alloc_histogram_value (cfun, HIST_TYPE_POW2, stmt, divisor)); val = build2 (TRUNC_DIV_EXPR, type, op0, divisor); hist = gimple_alloc_histogram_value (cfun, HIST_TYPE_INTERVAL, stmt, val); hist->hdata.intvl.int_start = 0; hist->hdata.intvl.steps = 2; VEC_quick_push (histogram_value, *values, hist); } return; default: return; } } /* Find calls inside STMT for that we want to measure histograms for indirect/virtual call optimization. */ static void gimple_indirect_call_to_profile (gimple stmt, histogram_values *values) { tree callee; if (gimple_code (stmt) != GIMPLE_CALL || gimple_call_internal_p (stmt) || gimple_call_fndecl (stmt) != NULL_TREE) return; callee = gimple_call_fn (stmt); VEC_reserve (histogram_value, heap, *values, 3); VEC_quick_push (histogram_value, *values, gimple_alloc_histogram_value (cfun, HIST_TYPE_INDIR_CALL, stmt, callee)); return; } /* Find values inside STMT for that we want to measure histograms for string operations. */ static void gimple_stringops_values_to_profile (gimple stmt, histogram_values *values) { tree fndecl; tree blck_size; tree dest; int size_arg; if (gimple_code (stmt) != GIMPLE_CALL) return; fndecl = gimple_call_fndecl (stmt); if (!fndecl) return; if (!interesting_stringop_to_profile_p (fndecl, stmt, &size_arg)) return; dest = gimple_call_arg (stmt, 0); blck_size = gimple_call_arg (stmt, size_arg); if (TREE_CODE (blck_size) != INTEGER_CST) { VEC_safe_push (histogram_value, heap, *values, gimple_alloc_histogram_value (cfun, HIST_TYPE_SINGLE_VALUE, stmt, blck_size)); VEC_safe_push (histogram_value, heap, *values, gimple_alloc_histogram_value (cfun, HIST_TYPE_AVERAGE, stmt, blck_size)); } if (TREE_CODE (blck_size) != INTEGER_CST) VEC_safe_push (histogram_value, heap, *values, gimple_alloc_histogram_value (cfun, HIST_TYPE_IOR, stmt, dest)); } /* Find values inside STMT for that we want to measure histograms and adds them to list VALUES. */ static void gimple_values_to_profile (gimple stmt, histogram_values *values) { gimple_divmod_values_to_profile (stmt, values); gimple_stringops_values_to_profile (stmt, values); gimple_indirect_call_to_profile (stmt, values); } void gimple_find_values_to_profile (histogram_values *values) { basic_block bb; gimple_stmt_iterator gsi; unsigned i; histogram_value hist = NULL; *values = NULL; FOR_EACH_BB (bb) for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) gimple_values_to_profile (gsi_stmt (gsi), values); FOR_EACH_VEC_ELT (histogram_value, *values, i, hist) { switch (hist->type) { case HIST_TYPE_INTERVAL: hist->n_counters = hist->hdata.intvl.steps + 2; break; case HIST_TYPE_POW2: hist->n_counters = 2; break; case HIST_TYPE_SINGLE_VALUE: hist->n_counters = 3; break; case HIST_TYPE_CONST_DELTA: hist->n_counters = 4; break; case HIST_TYPE_INDIR_CALL: hist->n_counters = 3; break; case HIST_TYPE_AVERAGE: hist->n_counters = 2; break; case HIST_TYPE_IOR: hist->n_counters = 1; break; default: gcc_unreachable (); } if (dump_file) { fprintf (dump_file, "Stmt "); print_gimple_stmt (dump_file, hist->hvalue.stmt, 0, TDF_SLIM); dump_histogram_value (dump_file, hist); } } }