X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fana%2Fexecfreq.c;h=d32569d008072cd3faae620819b265fdc20ed6bb;hb=555593b0aebec433b871920acc2b0a869b072055;hp=d2b9d85382a5f487566e5aa59a7251fdb8d0b1f5;hpb=4881b50207e092572f1421f78cdc12bb14794806;p=libfirm diff --git a/ir/ana/execfreq.c b/ir/ana/execfreq.c index d2b9d8538..d32569d00 100644 --- a/ir/ana/execfreq.c +++ b/ir/ana/execfreq.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved. + * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved. * * This file is part of libFirm. * @@ -22,29 +22,22 @@ * @brief Compute an estimate of basic block executions. * @author Adam M. Szalkowski * @date 28.05.2006 - * @version $Id$ */ -#ifdef HAVE_CONFIG_H #include "config.h" -#endif - -#undef USE_GSL #include #include #include #include -#ifdef USE_GSL -#include -#include -#else -#include "gaussjordan.h" -#endif +#include "gaussseidel.h" -#include "firm_common_t.h" #include "set.h" #include "hashptr.h" +#include "debug.h" +#include "statev_t.h" +#include "dfs_t.h" +#include "absgraph.h" #include "irprog_t.h" #include "irgraph_t.h" @@ -52,337 +45,283 @@ #include "irloop.h" #include "irgwalk.h" #include "iredges.h" +#include "irouts.h" #include "irprintf.h" +#include "util.h" #include "irhooks.h" +#include "irnodehashmap.h" -#include "execfreq.h" +#include "execfreq_t.h" -#define set_foreach(s,i) for((i)=set_first((s)); (i); (i)=set_next((s))) +#define EPSILON 1e-5 +#define UNDEF(x) (fabs(x) < EPSILON) +#define SEIDEL_TOLERANCE 1e-7 #define MAX_INT_FREQ 1000000 -typedef struct _freq_t { - const ir_node *irn; - double freq; -} freq_t; - - -typedef struct _walkerdata_t { - set *set; - size_t idx; -} walkerdata_t; - -struct ir_exec_freq { - set *set; - hook_entry_t hook; - double max; - double min_non_zero; - double m, b; - unsigned infeasible : 1; -}; +static hook_entry_t hook; -static int -cmp_freq(const void *a, const void *b, size_t size) +double get_block_execfreq(const ir_node *block) { - const freq_t *p = a; - const freq_t *q = b; - - return !(p->irn == q->irn); + return block->attr.block.execfreq; } -static freq_t * -set_find_freq(set * set, const ir_node * irn) +void set_block_execfreq(ir_node *block, double newfreq) { - freq_t query; - - query.irn = irn; - return set_find(set, &query, sizeof(query), HASH_PTR(irn)); + block->attr.block.execfreq = newfreq; } -static freq_t * -set_insert_freq(set * set, const ir_node * irn) +static void exec_freq_node_info(void *ctx, FILE *f, const ir_node *irn) { - freq_t query; - - query.irn = irn; - query.freq = 0.0; - return set_insert(set, &query, sizeof(query), HASH_PTR(irn)); + (void)ctx; + if (!is_Block(irn)) + return; + double freq = get_block_execfreq(irn); + if (freq != 0.0) + fprintf(f, "execution frequency: %g\n", freq); } -double -get_block_execfreq(const ir_exec_freq *ef, const ir_node * irn) +void init_execfreq(void) { - if(!ef->infeasible) { - set *freqs = ef->set; - freq_t *freq; - assert(is_Block(irn)); - freq = set_find_freq(freqs, irn); - assert(freq); - - assert(freq->freq >= 0); - return freq->freq; - } - - return 1.0; + memset(&hook, 0, sizeof(hook)); + hook.hook._hook_node_info = exec_freq_node_info; + register_hook(hook_node_info, &hook); } -unsigned long -get_block_execfreq_ulong(const ir_exec_freq *ef, const ir_node *bb) +void exit_execfreq(void) { - double f = get_block_execfreq(ef, bb); - int res = (int) (f > ef->min_non_zero ? ef->m * f + ef->b : 1.0); - - // printf("%20.6f %10d\n", f, res); - return res; + unregister_hook(hook_node_info, &hook); } -#define EPSILON 0.0001 -#define UNDEF(x) !(x > EPSILON) -static void -block_walker(ir_node * bb, void * data) +static double *solve_lgs(gs_matrix_t *mat, double *x, int size) { - walkerdata_t *wd = data; - - set_insert_freq(wd->set, bb); - set_irn_link(bb, (void*)wd->idx++); + double init = 1.0 / size; + double dev; + int i, iter = 0; + + /* better convergence. */ + for (i = 0; i < size; ++i) + x[i] = init; + + stat_ev_dbl("execfreq_matrix_size", size); + stat_ev_tim_push(); + do { + ++iter; + dev = gs_matrix_gauss_seidel(mat, x, size); + } while (fabs(dev) > SEIDEL_TOLERANCE); + stat_ev_tim_pop("execfreq_seidel_time"); + stat_ev_dbl("execfreq_seidel_iter", iter); + + return x; } -#ifdef USE_GSL -static gsl_vector * -solve_lgs(double * a_data, double * b_data, size_t size) +/* + * Determine probability that predecessor pos takes this cf edge. + */ +static double get_cf_probability(const ir_node *bb, int pos, double loop_weight) { - gsl_matrix_view m - = gsl_matrix_view_array (a_data, size, size); - - gsl_vector_view b - = gsl_vector_view_array (b_data, size); - - gsl_vector *x = gsl_vector_alloc (size); - - int s; + double sum = 0.0; + double cur = 1.0; + double inv_loop_weight = 1./loop_weight; + const ir_node *pred = get_Block_cfgpred_block(bb, pos); + const ir_loop *pred_loop; + int pred_depth; + const ir_loop *loop; + int depth; + int d; + + if (is_Bad(pred)) + return 0; + + loop = get_irn_loop(bb); + depth = get_loop_depth(loop); + pred_loop = get_irn_loop(pred); + pred_depth = get_loop_depth(pred_loop); + + for (d = depth; d < pred_depth; ++d) { + cur *= inv_loop_weight; + } - gsl_permutation * p = gsl_permutation_alloc (size); + foreach_block_succ(pred, edge) { + const ir_node *succ = get_edge_src_irn(edge); + const ir_loop *succ_loop = get_irn_loop(succ); + int succ_depth = get_loop_depth(succ_loop); - gsl_linalg_LU_decomp (&m.matrix, p, &s); + double fac = 1.0; + for (d = succ_depth; d < pred_depth; ++d) { + fac *= inv_loop_weight; + } + sum += fac; + } - gsl_linalg_LU_solve (&m.matrix, p, &b.vector, x); + return cur/sum; +} - gsl_permutation_free (p); +static double *freqs; +static double min_non_zero; +static double max_freq; - return x; -} -#else -static double * -solve_lgs(double * A, double * b, size_t size) +static void collect_freqs(ir_node *node, void *data) { - if(firm_gaussjordansolve(A,b,size) == 0) { - return b; - } else { - return NULL; - } + (void) data; + double freq = get_block_execfreq(node); + if (freq > max_freq) + max_freq = freq; + if (freq > 0.0 && freq < min_non_zero) + min_non_zero = freq; + ARR_APP1(double, freqs, freq); } -#endif /* USE_GSL */ -static double -get_cf_probability(ir_node *bb, int pos, double loop_weight) +void ir_calculate_execfreq_int_factors(ir_execfreq_int_factors *factors, + ir_graph *irg) { - double sum = 0.0; - double cur = 0.0; - const ir_node *pred = get_Block_cfgpred_block(bb, pos); - const ir_loop *pred_loop = get_irn_loop(pred); - int pred_depth = get_loop_depth(pred_loop); - const ir_edge_t *edge; + /* compute m and b of the transformation used to convert the doubles into + * scaled ints */ + freqs = NEW_ARR_F(double, 0); + min_non_zero = HUGE_VAL; + max_freq = 0.0; + irg_block_walk_graph(irg, collect_freqs, NULL, NULL); + + /* + * find the smallest difference of the execution frequencies + * we try to ressolve it with 1 integer. + */ + size_t n_freqs = ARR_LEN(freqs); + double smallest_diff = 1.0; + for (size_t i = 0; i < n_freqs; ++i) { + if (freqs[i] <= 0.0) + continue; - cur = get_loop_depth(get_irn_loop(bb)) < get_loop_depth(get_irn_loop(pred)) ? 1.0 : loop_weight; + for (size_t j = i + 1; j < n_freqs; ++j) { + double diff = fabs(freqs[i] - freqs[j]); - foreach_block_succ(pred, edge) { - const ir_node *block = get_edge_src_irn(edge); - const ir_loop *loop = get_irn_loop(block); - int depth = get_loop_depth(loop); - sum += depth < pred_depth ? 1.0 : loop_weight; + if (!UNDEF(diff)) + smallest_diff = MIN(diff, smallest_diff); + } } - return cur/sum; -} - -static void exec_freq_node_info(void *ctx, FILE *f, const ir_node *irn) -{ - if(is_Block(irn)) { - ir_exec_freq *ef = ctx; - fprintf(f, "execution frequency: %g/%lu\n", get_block_execfreq(ef, irn), get_block_execfreq_ulong(ef, irn)); + double l2 = min_non_zero; + double h2 = max_freq; + double l1 = 1.0; + double h1 = MAX_INT_FREQ; + + /* according to that the slope of the translation function is + * 1.0 / smallest_diff */ + factors->m = 1.0 / smallest_diff; + + /* the abscissa is then given by */ + factors->b = l1 - factors->m * l2; + + /* + * if the slope is so high that the largest integer would be larger than + * MAX_INT_FREQ set the largest int freq to that upper limit and recompute + * the translation function + */ + if (factors->m * h2 + factors->b > MAX_INT_FREQ) { + factors->m = (h1 - l1) / (h2 - l2); + factors->b = l1 - factors->m * l2; } -} - -ir_exec_freq *create_execfreq(ir_graph *irg) -{ - ir_exec_freq *execfreq = xmalloc(sizeof(execfreq[0])); - memset(execfreq, 0, sizeof(execfreq[0])); - execfreq->set = new_set(cmp_freq, 32); - memset(&execfreq->hook, 0, sizeof(execfreq->hook)); - execfreq->hook.context = execfreq; - execfreq->hook.hook._hook_node_info = exec_freq_node_info; - register_hook(hook_node_info, &execfreq->hook); - - return execfreq; + DEL_ARR_F(freqs); } -void set_execfreq(ir_exec_freq *execfreq, const ir_node *block, double freq) +int get_block_execfreq_int(const ir_execfreq_int_factors *factors, + const ir_node *block) { - freq_t *f = set_insert_freq(execfreq->set, block); - f->freq = freq; + double f = get_block_execfreq(block); + int res = (int) (f > factors->min_non_zero ? factors->m * f + factors->b : 1.0); + return res; } -ir_exec_freq * -compute_execfreq(ir_graph * irg, double loop_weight) +void ir_estimate_execfreq(ir_graph *irg) { - size_t size; - double *matrix; - double *rhs; - int i; - freq_t *freq; - walkerdata_t wd; - ir_exec_freq *ef; - set *freqs; -#ifdef USE_GSL - gsl_vector *x; -#else - double *x; -#endif - - ef = xmalloc(sizeof(ef[0])); - memset(ef, 0, sizeof(ef[0])); - ef->min_non_zero = 1e50; /* initialize with a reasonable large number. */ - freqs = ef->set = new_set(cmp_freq, 32); - - construct_cf_backedges(irg); - edges_assure(irg); - - wd.idx = 0; - wd.set = freqs; - - irg_block_walk_graph(irg, block_walker, NULL, &wd); - - size = set_count(freqs); - matrix = xmalloc(size*size*sizeof(*matrix)); - memset(matrix, 0, size*size*sizeof(*matrix)); - rhs = xmalloc(size*sizeof(*rhs)); - memset(rhs, 0, size*sizeof(*rhs)); - - set_foreach(freqs, freq) { - ir_node *bb = (ir_node *)freq->irn; - size_t idx = (int)get_irn_link(bb); - - matrix[idx * (size + 1)] = -1.0; - - if (bb == get_irg_start_block(irg)) { - rhs[(int)get_irn_link(bb)] = -1.0; - continue; + double loop_weight = 10.0; + + assure_irg_properties(irg, + IR_GRAPH_PROPERTY_CONSISTENT_OUT_EDGES + | IR_GRAPH_PROPERTY_CONSISTENT_LOOPINFO + | IR_GRAPH_PROPERTY_NO_UNREACHABLE_CODE); + + /* compute a DFS. + * using a toposort on the CFG (without back edges) will propagate + * the values better for the gauss/seidel iteration. + * => they can "flow" from start to end. + */ + dfs_t *dfs = dfs_new(&absgraph_irg_cfg_succ, irg); + + int size = dfs_get_n_nodes(dfs); + gs_matrix_t *mat = gs_new_matrix(size, size); + + ir_node *end_block = get_irg_end_block(irg); + + for (int idx = size - 1; idx >= 0; --idx) { + const ir_node *bb = (ir_node*)dfs_get_post_num_node(dfs, size-idx-1); + + /* Sum of (execution frequency of predecessor * probability of cf edge) ... */ + for (int i = get_Block_n_cfgpreds(bb) - 1; i >= 0; --i) { + const ir_node *pred = get_Block_cfgpred_block(bb, i); + int pred_idx = size - dfs_get_post_num(dfs, pred)-1; + double cf_probability = get_cf_probability(bb, i, loop_weight); + gs_matrix_set(mat, idx, pred_idx, cf_probability); } - - for(i = get_Block_n_cfgpreds(bb) - 1; i >= 0; --i) { - ir_node *pred = get_Block_cfgpred_block(bb, i); - size_t pred_idx = (int)get_irn_link(pred); - - // matrix[pred_idx + idx*size] += 1.0/(double)get_Block_n_cfg_outs(pred); - matrix[pred_idx + idx * size] += get_cf_probability(bb, i, loop_weight); + /* ... equals my execution frequency */ + gs_matrix_set(mat, idx, idx, -1.0); + + /* Add an edge from end to start. + * The problem is then an eigenvalue problem: + * Solve A*x = 1*x => (A-I)x = 0 + */ + if (bb == end_block) { + const ir_node *start_block = get_irg_start_block(irg); + int s_idx = size - dfs_get_post_num(dfs, start_block)-1; + gs_matrix_set(mat, s_idx, idx, 1.0); } } - x = solve_lgs(matrix, rhs, size); - if (x == NULL) { - ef->infeasible = 1; - } else { - ef->max = 0.0; - - set_foreach(freqs, freq) { - const ir_node *bb = freq->irn; - size_t idx = PTR_TO_INT(get_irn_link(bb)); - -#ifdef USE_GSL - freq->freq = UNDEF(gsl_vector_get(x, idx)) ? EPSILON : gsl_vector_get(x, idx); -#else - freq->freq = UNDEF(x[idx]) ? EPSILON : x[idx]; -#endif - - /* get the maximum exec freq */ - ef->max = MAX(ef->max, freq->freq); - - /* Get the minimum non-zero execution frequency. */ - if(freq->freq > 0.0) - ef->min_non_zero = MIN(ef->min_non_zero, freq->freq); - } - - /* compute m and b of the transformation used to convert the doubles into scaled ints */ - { - double smallest_diff = 1.0; - - double l2 = ef->min_non_zero; - double h2 = ef->max; - double l1 = 1.0; - double h1 = MAX_INT_FREQ; - - double *fs = malloc(set_count(freqs) * sizeof(fs[0])); - int i, j, n = 0; - - set_foreach(freqs, freq) - fs[n++] = freq->freq; - - /* - * find the smallest difference of the execution frequencies - * we try to ressolve it with 1 integer. - */ - for(i = 0; i < n; ++i) { - if(fs[i] <= 0.0) - continue; - - for(j = i + 1; j < n; ++j) { - double diff = fabs(fs[i] - fs[j]); - - if(!UNDEF(diff)) - smallest_diff = MIN(diff, smallest_diff); - } - } - - /* according to that the slope of the translation function is 1.0 / smallest diff */ - ef->m = 1.0 / smallest_diff; - - /* the abscissa is then given by */ - ef->b = l1 - ef->m * l2; - - /* - * if the slope is so high that the largest integer would be larger than MAX_INT_FREQ - * set the largest int freq to that upper limit and recompute the translation function - */ - if(ef->m * h2 + ef->b > MAX_INT_FREQ) { - ef->m = (h1 - l1) / (h2 - l2); - ef->b = l1 - ef->m * l2; - } - - // printf("smallest_diff: %g, l1: %f, h1: %f, l2: %f, h2: %f, m: %f, b: %f\n", smallest_diff, l1, h1, l2, h2, ef->m, ef->b); - free(fs); - } + /* + * Also add an edge for each kept block to start. + * + * This avoid strange results for e.g. an irg containing a exit()-call + * which block has no cfg successor. + */ + ir_node *start_block = get_irg_start_block(irg); + int s_idx = size - dfs_get_post_num(dfs, start_block)-1; + const ir_node *end = get_irg_end(irg); + int n_keepalives = get_End_n_keepalives(end); + for (int idx = n_keepalives - 1; idx >= 0; --idx) { + ir_node *keep = get_End_keepalive(end, idx); + if (!is_Block(keep) || get_irn_n_edges_kind(keep, EDGE_KIND_BLOCK) > 0) + continue; -#ifdef USE_GSL - gsl_vector_free(x); -#endif - memset(&ef->hook, 0, sizeof(ef->hook)); - ef->hook.context = ef; - ef->hook.hook._hook_node_info = exec_freq_node_info; - register_hook(hook_node_info, &ef->hook); + int k_idx = size-dfs_get_post_num(dfs, keep)-1; + if (k_idx > 0) + gs_matrix_set(mat, s_idx, k_idx, 1.0); } - free(matrix); - free(rhs); + /* solve the system and delete the matrix */ + double *x = XMALLOCN(double, size); + solve_lgs(mat, x, size); + gs_delete_matrix(mat); + + /* compute the normalization factor. + * 1.0 / exec freq of start block. + * (note: start_idx is != 0 in strange cases involving endless loops, + * probably a misfeature/bug) + */ + int start_idx = size-dfs_get_post_num(dfs, get_irg_start_block(irg))-1; + double start_freq = x[start_idx]; + double norm = start_freq != 0.0 ? 1.0 / start_freq : 1.0; + + for (int idx = size - 1; idx >= 0; --idx) { + ir_node *bb = (ir_node *) dfs_get_post_num_node(dfs, size - idx - 1); + + /* take abs because it sometimes can be -0 in case of endless loops */ + double freq = fabs(x[idx]) * norm; + set_block_execfreq(bb, freq); + } - return ef; -} + dfs_free(dfs); -void -free_execfreq(ir_exec_freq *ef) -{ - del_set(ef->set); - unregister_hook(hook_node_info, &ef->hook); - free(ef); + xfree(x); }