X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fopt%2Fopt_confirms.c;h=817ebe726364139eba8b071bfbc4e78587b95606;hb=b7cff2afb7eb19817425b554b1786509f67435f1;hp=9c73b3e4e4d7ff4621cbfb91ff05a6941c639282;hpb=05e879d227e8ec8712a4ffc1c3d8bf82ca583f09;p=libfirm diff --git a/ir/opt/opt_confirms.c b/ir/opt/opt_confirms.c index 9c73b3e4e..817ebe726 100644 --- a/ir/opt/opt_confirms.c +++ b/ir/opt/opt_confirms.c @@ -1,29 +1,44 @@ /* - * Project: libFIRM - * File name: ir/opt/opt_confirms.c - * Purpose: Optimizations regarding Confirm nodes - * Author: Michael Beck - * Modified by: - * Created: - * CVS-ID: $Id$ - * Copyright: (c) 1998-2005 Universität Karlsruhe - * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE. + * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved. + * + * This file is part of libFirm. + * + * This file may be distributed and/or modified under the terms of the + * GNU General Public License version 2 as published by the Free Software + * Foundation and appearing in the file LICENSE.GPL included in the + * packaging of this file. + * + * Licensees holding valid libFirm Professional Edition licenses may use + * this file in accordance with the libFirm Commercial License. + * Agreement provided with the Software. + * + * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE + * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE. */ -#ifdef HAVE_CONFIG_H -# include "config.h" -#endif +/** + * @file + * @brief Optimizations regarding Confirm nodes. + * @author Michael Beck + */ +#include "config.h" + +#undef DEBUG_CONFIRM #include "tv_t.h" +#include "irnode_t.h" #include "iropt_t.h" #include "iropt_dbg.h" -#include "opt_confirms.h" +#include "iroptimize.h" +#include "irflag_t.h" +#include "irprintf.h" enum range_tags { - MIN_INCLUDED = 0x00, /**< [min, ... */ - MAX_INCLUDED = 0x00, /**< ..., max] */ - MIN_EXCLUDED = 0x01, /**< (min, ... */ - MAX_EXCLUDED = 0x02 /**< ..., max) */ + MIN_INCLUDED = 0x00, /**< [min, ... */ + MAX_INCLUDED = 0x00, /**< ..., max] */ + MIN_EXCLUDED = 0x01, /**< (min, ... */ + MAX_EXCLUDED = 0x02 /**< ..., max) */ }; /** @@ -34,170 +49,290 @@ enum range_tags { * such kind of operation, we use border flags allowing * all intervals. */ -typedef struct _interval_t { - tarval *min; /**< lowest border */ - tarval *max; /**< highest border */ - unsigned char flags; /**< border flags */ +typedef struct interval_t { + ir_tarval *min; /**< lowest border */ + ir_tarval *max; /**< highest border */ + unsigned char flags; /**< border flags */ } interval_t; -/** +#ifdef DEBUG_CONFIRM + +#define compare_iv(l_iv, r_iv, relation) compare_iv_dbg(l_iv, r_iv, relation) + +/* forward */ +static tarval *compare_iv_dbg(const interval_t *l_iv, const interval_t *r_iv, ir_relation relation); + +/* triangle */ +#define DBG_OUT_TR(l_relation, l_bound, r_relation, r_bound, relation, v) \ + ir_printf("In %e:\na %= %n && b %= %n ==> a %= b == %s\n", \ + get_irg_entity(current_ir_graph), \ + l_relation, l_bound, r_relation, r_bound, relation, v) + +/* right side */ +#define DBG_OUT_R(r_relation, r_bound, left, relation, right, v) \ + ir_printf("In %e:\na %= %n ==> %n %= %n == %s\n", \ + get_irg_entity(current_ir_graph), \ + r_relation, r_bound, left, relation, right, v) + +/* left side */ +#define DBG_OUT_L(l_relation, l_bound, left, relation, right, v) \ + ir_printf("In %e:\na %= %n ==> %n %= %n == %s\n", \ + get_irg_entity(current_ir_graph), \ + l_relation, l_bound, left, relation, right, v) + +#else + +#define DBG_OUT_TR(l_relation, l_bound, r_relation, r_bound, relation, v) (void)0 +#define DBG_OUT_R(r_relation, r_bound, left, relation, right, v) (void)0 +#define DBG_OUT_L(l_relation, l_bound, left, relation, right, v) (void)0 + +#endif /* DEBUG_CONFIRM */ + +/* * Check, if the value of a node is != 0. * * This is a often needed case, so we handle here Confirm * nodes too. */ -int value_not_zero(ir_node *n) +int value_not_zero(const ir_node *n, const ir_node **confirm) { -#define RET_ON(x) if (x) return 1; break - - tarval *tv; - ir_mode *mode = get_irn_mode(n); - pn_Cmp pnc; - - while (get_irn_op(n) == op_Confirm) { - /* - * Note: A Confirm is never after a Const. So, - * we simply can check the bound for beeing a Const - * without the fear that is might be hidden by a further Confirm. - */ - tv = value_of(get_Confirm_bound(n)); - if (tv == tarval_bad) - return 0; - - pnc = tarval_cmp(tv, get_mode_null(mode)); - - /* - * Beware: C might by a NaN. It is not clear, what we should do - * than. Of course a NaN is != 0, but we might use this function - * to remove up Exceptions, and NaN's might generate Exception. - * So, we do NOT handle NaNs here for safety. - * - * Note that only the C != 0 case need additional checking. - */ - switch (get_Confirm_cmp(n)) { - case pn_Cmp_Eq: /* n == C /\ C != 0 ==> n != 0 */ - RET_ON(pnc != pn_Cmp_Eq && pnc != pn_Cmp_Uo); - case pn_Cmp_Lg: /* n != C /\ C == 0 ==> n != 0 */ - RET_ON(pnc == pn_Cmp_Eq); - case pn_Cmp_Lt: /* n < C /\ C <= 0 ==> n != 0 */ - RET_ON(pnc == pn_Cmp_Lt || pnc == pn_Cmp_Eq); - case pn_Cmp_Le: /* n <= C /\ C < 0 ==> n != 0 */ - RET_ON(pnc == pn_Cmp_Lt); - case pn_Cmp_Ge: /* n >= C /\ C > 0 ==> n != 0 */ - RET_ON(pnc == pn_Cmp_Gt); - case pn_Cmp_Gt: /* n > C /\ C >= 0 ==> n != 0 */ - RET_ON(pnc == pn_Cmp_Gt || pnc == pn_Cmp_Eq); - default: - break; - } - - /* there might be several Confirms one after other that form an interval */ - n = get_Confirm_value(n); - } - tv = value_of(n); - - if (tv == tarval_bad) - return 0; - - pnc = tarval_cmp(tv, get_mode_null(mode)); - - /* again, need check for NaN */ - return (pnc != pn_Cmp_Eq) && (pnc != pn_Cmp_Uo); +#define RET_ON(x) if (x) { *confirm = n; return 1; } break + + ir_tarval *tv; + ir_mode *mode = get_irn_mode(n); + ir_relation relation; + + *confirm = NULL; + + /* there might be several Confirms one after other that form an interval */ + for (;;) { + if (is_Minus(n)) { + /* we can safely skip Minus when checking for != 0 */ + n = get_unop_op(n); + continue; + } + if (! is_Confirm(n)) + break; + + /* + * Note: A Confirm is never after a Const. So, + * we simply can check the bound for being a Const + * without the fear that is might be hidden by a further Confirm. + */ + tv = value_of(get_Confirm_bound(n)); + if (tv == tarval_bad) + return 0; + + relation = tarval_cmp(tv, get_mode_null(mode)); + + /* + * Beware: C might by a NaN. It is not clear, what we should do + * than. Of course a NaN is != 0, but we might use this function + * to remove up Exceptions, and NaN's might generate Exception. + * So, we do NOT handle NaNs here for safety. + * + * Note that only the C != 0 case need additional checking. + */ + switch (get_Confirm_relation(n)) { + case ir_relation_equal: /* n == C /\ C != 0 ==> n != 0 */ + RET_ON(relation != ir_relation_equal && relation != ir_relation_unordered); + case ir_relation_less_greater: /* n != C /\ C == 0 ==> n != 0 */ + RET_ON(relation == ir_relation_equal); + case ir_relation_less: /* n < C /\ C <= 0 ==> n != 0 */ + RET_ON(relation == ir_relation_less || relation == ir_relation_equal); + case ir_relation_less_equal: /* n <= C /\ C < 0 ==> n != 0 */ + RET_ON(relation == ir_relation_less); + case ir_relation_greater_equal: /* n >= C /\ C > 0 ==> n != 0 */ + RET_ON(relation == ir_relation_greater); + case ir_relation_greater: /* n > C /\ C >= 0 ==> n != 0 */ + RET_ON(relation == ir_relation_greater || relation == ir_relation_equal); + default: + break; + } + n = get_Confirm_value(n); + } + tv = value_of(n); + + if (tv == tarval_bad) + return 0; + + relation = tarval_cmp(tv, get_mode_null(mode)); + + /* again, need check for NaN */ + return (relation != ir_relation_equal) && (relation != ir_relation_unordered); #undef RET_ON +} /* value_not_zero */ + +/* + * Check, if the value of a node cannot represent a NULL pointer. + * + * - Casts are skipped, Sels are skipped + * - A SymConst(entity) is NEVER a NULL pointer + * - Confirms are evaluated + */ +int value_not_null(const ir_node *n, const ir_node **confirm) +{ + ir_tarval *tv; + + *confirm = NULL; + n = skip_Cast_const(n); + + tv = value_of(n); + if (tarval_is_constant(tv) && ! tarval_is_null(tv)) + return 1; + + assert(mode_is_reference(get_irn_mode(n))); + /* skip all Sel nodes and Cast's */ + while (is_Sel(n)) { + n = skip_Cast(get_Sel_ptr(n)); + } + while (1) { + if (is_Cast(n)) { n = get_Cast_op(n); continue; } + if (is_Proj(n)) { n = get_Proj_pred(n); continue; } + break; + } + + if (is_SymConst_addr_ent(n)) { + /* global references are never NULL */ + return 1; + } else if (n == get_irg_frame(get_irn_irg(n))) { + /* local references are never NULL */ + return 1; + } else if (is_Alloc(n)) { + /* alloc never returns NULL (it throws an exception instead) */ + return 1; + } else { + /* check for more Confirms */ + for (; is_Confirm(n); n = skip_Cast(get_Confirm_value(n))) { + if (get_Confirm_relation(n) == ir_relation_less_greater) { + ir_node *bound = get_Confirm_bound(n); + ir_tarval *tv = value_of(bound); + + if (tarval_is_null(tv)) { + *confirm = n; + return 1; + } + } + } + } + return 0; +} /* value_not_null */ + +#ifdef __cplusplus +extern "C++" { + static inline ir_value_classify_sign operator *(ir_value_classify_sign sign, int mul) { + return (ir_value_classify_sign) (sign*mul); + } } +#endif /* * Check, if the value of a node can be confirmed >= 0 or <= 0, * If the mode of the value did not honor signed zeros, else * check for >= 0 or < 0. */ -value_classify classify_value_sign(ir_node *n) +ir_value_classify_sign classify_value_sign(ir_node *n) { - tarval *tv, *c; - ir_mode *mode; - pn_Cmp cmp, ncmp; - - if (get_irn_op(n) != op_Confirm) - return VALUE_UNKNOWN; - - tv = value_of(get_Confirm_bound(n)); - if (tv == tarval_bad) - return VALUE_UNKNOWN; - - mode = get_irn_mode(n); - - /* - * We can handle only >=, >, <, <= cases. - * We could handle == too, but this will be optimized into - * a constant either. - * - * Note that for integer modes we have a slightly better - * optimization possibilities, so we handle this - * different. - */ - cmp = get_Confirm_cmp(n); - - switch (cmp) { - case pn_Cmp_Lt: - /* - * must be x < c <= 1 to be useful if integer mode and -0 = 0 - * x < c <= 0 to be useful else - */ - case pn_Cmp_Le: - /* - * must be x <= c < 1 to be useful if integer mode and -0 = 0 - * x <= c < 0 to be useful else - */ - c = mode_is_int(mode) && mode_honor_signed_zeros(mode) ? - get_mode_one(mode) : get_mode_null(mode); - - ncmp = tarval_cmp(tv, c); - if (ncmp == pn_Cmp_Eq) - ncmp = pn_Cmp_Le; - - if (cmp != (ncmp ^ pn_Cmp_Eq)) - return VALUE_UNKNOWN; - - /* yep, negative */ - return VALUE_NEGATIVE; - - case pn_Cmp_Ge: - /* - * must be x >= c > -1 to be useful if integer mode - * x >= c >= 0 to be useful else - */ - case pn_Cmp_Gt: - /* - * must be x > c >= -1 to be useful if integer mode - * x > c >= 0 to be useful else - */ - if (mode_is_int(mode)) { - c = get_mode_minus_one(mode); - - ncmp = tarval_cmp(tv, c); - if (ncmp == pn_Cmp_Eq) - ncmp = pn_Cmp_Ge; - - if (cmp != (ncmp ^ pn_Cmp_Eq)) - return VALUE_UNKNOWN; - } - else { - c = get_mode_minus_one(mode); - - ncmp = tarval_cmp(tv, c); - - if (ncmp != pn_Cmp_Eq && ncmp != pn_Cmp_Gt) - return VALUE_UNKNOWN; - } - - /* yep, positive */ - return VALUE_POSITIVE; - - default: - return VALUE_UNKNOWN; - } -} + ir_tarval *tv, *c; + ir_mode *mode; + ir_relation cmp, ncmp; + int negate = 1; + + for (;;) { + unsigned code = get_irn_opcode(n); + + switch (code) { + case iro_Minus: + negate *= -1; + n = get_Minus_op(n); + continue; + case iro_Confirm: + break; + default: + return value_classified_unknown; + } + break; + } + if (!is_Confirm(n)) + return value_classified_unknown; + + tv = value_of(get_Confirm_bound(n)); + if (tv == tarval_bad) + return value_classified_unknown; + + mode = get_irn_mode(n); + + /* + * We can handle only >=, >, <, <= cases. + * We could handle == too, but this will be optimized into + * a constant either. + * + * Note that for integer modes we have a slightly better + * optimization possibilities, so we handle this + * different. + */ + cmp = get_Confirm_relation(n); + + switch (cmp) { + case ir_relation_less: + /* + * must be x < c <= 1 to be useful if integer mode and -0 = 0 + * x < c <= 0 to be useful else + */ + case ir_relation_less_equal: + /* + * must be x <= c < 1 to be useful if integer mode and -0 = 0 + * x <= c < 0 to be useful else + */ + c = mode_is_int(mode) && mode_honor_signed_zeros(mode) ? + get_mode_one(mode) : get_mode_null(mode); + + ncmp = tarval_cmp(tv, c); + if (ncmp == ir_relation_equal) + ncmp = ir_relation_less_equal; + + if (cmp != (ncmp ^ ir_relation_equal)) + return value_classified_unknown; + + /* yep, negative */ + return value_classified_negative * negate; + + case ir_relation_greater_equal: + /* + * must be x >= c > -1 to be useful if integer mode + * x >= c >= 0 to be useful else + */ + case ir_relation_greater: + /* + * must be x > c >= -1 to be useful if integer mode + * x > c >= 0 to be useful else + */ + if (mode_is_int(mode)) { + c = get_mode_minus_one(mode); + + ncmp = tarval_cmp(tv, c); + if (ncmp == ir_relation_equal) + ncmp = ir_relation_greater_equal; + + if (cmp != (ncmp ^ ir_relation_equal)) + return value_classified_unknown; + } else { + c = get_mode_minus_one(mode); + + ncmp = tarval_cmp(tv, c); + + if (ncmp != ir_relation_equal && ncmp != ir_relation_greater) + return value_classified_unknown; + } + + /* yep, positive */ + return value_classified_positive * negate; + + default: + return value_classified_unknown; + } +} /* classify_value_sign */ /** * construct an interval from a value @@ -205,375 +340,534 @@ value_classify classify_value_sign(ir_node *n) * @return the filled interval or NULL if no interval * can be created (happens only on floating point */ -static interval_t *get_interval_from_tv(interval_t *iv, tarval *tv) +static interval_t *get_interval_from_tv(interval_t *iv, ir_tarval *tv) { - ir_mode *mode = get_tarval_mode(tv); - - if (tv == tarval_bad) { - if (mode_is_float(mode)) { - /* NaN could be included which we cannot handle */ - iv->min = tarval_bad; - iv->max = tarval_bad; - iv->flags = MIN_EXCLUDED | MAX_EXCLUDED; - return NULL; - } - else { - /* [-oo, +oo] */ - iv->min = get_mode_min(mode); - iv->max = get_mode_max(mode); - iv->flags = MIN_INCLUDED | MAX_INCLUDED; - return iv; - } - } - - if (mode_is_float(mode)) { - if (tv == get_mode_NAN(mode)) { - /* arg, we cannot handle NaN's. */ - iv->min = tarval_bad; - iv->max = tarval_bad; - iv->flags = MIN_EXCLUDED | MAX_EXCLUDED; - return NULL; - } - } - - /* [tv, tv] */ - iv->min = tv; - iv->max = tv; - iv->flags = MIN_INCLUDED | MAX_INCLUDED; - - return iv; -} + ir_mode *mode = get_tarval_mode(tv); + + if (tv == tarval_bad) { + if (mode_is_float(mode)) { + /* NaN could be included which we cannot handle */ + iv->min = tarval_bad; + iv->max = tarval_bad; + iv->flags = MIN_EXCLUDED | MAX_EXCLUDED; + return NULL; + } else { + /* [-oo, +oo] */ + iv->min = get_mode_min(mode); + iv->max = get_mode_max(mode); + iv->flags = MIN_INCLUDED | MAX_INCLUDED; + return iv; + } + } + + if (mode_is_float(mode)) { + if (tv == get_mode_NAN(mode)) { + /* arg, we cannot handle NaN's. */ + iv->min = tarval_bad; + iv->max = tarval_bad; + iv->flags = MIN_EXCLUDED | MAX_EXCLUDED; + return NULL; + } + } + + /* [tv, tv] */ + iv->min = tv; + iv->max = tv; + iv->flags = MIN_INCLUDED | MAX_INCLUDED; + + return iv; +} /* get_interval_from_tv */ /** * construct an interval from a Confirm * - * @param iv an empty interval, will be filled - * @param bound the bound value - * @param pnc the Confirm pnc relation + * @param iv an empty interval, will be filled + * @param bound the bound value + * @param relation the Confirm compare relation * * @return the filled interval or NULL if no interval * can be created (happens only on floating point */ -static interval_t *get_interval(interval_t *iv, ir_node *bound, pn_Cmp pnc) +static interval_t *get_interval(interval_t *iv, ir_node *bound, ir_relation relation) { - ir_mode *mode = get_irn_mode(bound); - tarval *tv = value_of(bound); - - if (tv == tarval_bad) { - if (mode_is_float(mode)) { - /* NaN could be included which we cannot handle */ - iv->min = tarval_bad; - iv->max = tarval_bad; - iv->flags = MIN_EXCLUDED | MAX_EXCLUDED; - return NULL; - } - else { - /* [-oo, +oo] */ - iv->min = get_mode_min(mode); - iv->max = get_mode_max(mode); - iv->flags = MIN_INCLUDED | MAX_INCLUDED; - return iv; - } - } - - if (mode_is_float(mode)) { - if (tv == get_mode_NAN(mode)) { - /* arg, we cannot handle NaN's. */ - iv->min = tarval_bad; - iv->max = tarval_bad; - iv->flags = MIN_EXCLUDED | MAX_EXCLUDED; - - return NULL; - } - } - - /* check which side is known */ - switch (pnc) { - case pn_Cmp_Eq: - /* [tv, tv] */ - iv->min = - iv->max = tv; - iv->flags = MIN_INCLUDED | MAX_INCLUDED; - return iv; - - case pn_Cmp_Le: - /* [-oo, tv] */ - iv->min = get_mode_min(mode); - iv->max = tv; - iv->flags = MIN_INCLUDED | MAX_INCLUDED; - return iv; - - case pn_Cmp_Lt: - /* [-oo, tv) */ - iv->min = get_mode_min(mode); - iv->max = tv; - iv->flags = MIN_INCLUDED | MAX_EXCLUDED; - return iv; - - case pn_Cmp_Gt: - /* (tv, +oo] */ - iv->min = tv; - iv->max = get_mode_max(mode); - iv->flags = MIN_EXCLUDED | MAX_INCLUDED; - return iv; - - case pn_Cmp_Ge: - /* [tv, +oo] */ - iv->min = tv; - iv->max = get_mode_max(mode); - iv->flags = MIN_INCLUDED | MAX_INCLUDED; - return iv; - - case pn_Cmp_Leg: - /* - * Ordered means, that at least neither - * our bound nor our value ara NaN's - */ - /* [-oo, +oo] */ - iv->min = get_mode_min(mode); - iv->max = get_mode_max(mode); - iv->flags = MIN_INCLUDED | MAX_INCLUDED; - return iv; - - default: - /* - * We do not handle UNORDERED, as a NaN - * could be included in the interval. - */ - iv->min = tarval_bad; - iv->max = tarval_bad; - iv->flags = MIN_EXCLUDED | MAX_EXCLUDED; - return NULL; - } -} + ir_mode *mode = get_irn_mode(bound); + ir_tarval *tv = value_of(bound); + + if (tv == tarval_bad) { + /* There is nothing we could do here. For integer + * modes we could return [-oo, +oo], but there is + * nothing we could deduct from such an interval. + * So, speed things up and return unknown. + */ + iv->min = tarval_bad; + iv->max = tarval_bad; + iv->flags = MIN_EXCLUDED | MAX_EXCLUDED; + return NULL; + } + + if (mode_is_float(mode)) { + if (tv == get_mode_NAN(mode)) { + /* arg, we cannot handle NaN's. */ + iv->min = tarval_bad; + iv->max = tarval_bad; + iv->flags = MIN_EXCLUDED | MAX_EXCLUDED; + + return NULL; + } + } + + /* check which side is known */ + switch (relation) { + case ir_relation_equal: + /* [tv, tv] */ + iv->min = + iv->max = tv; + iv->flags = MIN_INCLUDED | MAX_INCLUDED; + break; + + case ir_relation_less_equal: + /* [-oo, tv] */ + iv->min = get_mode_min(mode); + iv->max = tv; + iv->flags = MIN_INCLUDED | MAX_INCLUDED; + break; + + case ir_relation_less: + /* [-oo, tv) */ + iv->min = get_mode_min(mode); + iv->max = tv; + iv->flags = MIN_INCLUDED | MAX_EXCLUDED; + break; + + case ir_relation_greater: + /* (tv, +oo] */ + iv->min = tv; + iv->max = get_mode_max(mode); + iv->flags = MIN_EXCLUDED | MAX_INCLUDED; + break; + + case ir_relation_greater_equal: + /* [tv, +oo] */ + iv->min = tv; + iv->max = get_mode_max(mode); + iv->flags = MIN_INCLUDED | MAX_INCLUDED; + break; + + case ir_relation_less_equal_greater: + /* + * Ordered means, that at least neither + * our bound nor our value ara NaN's + */ + /* [-oo, +oo] */ + iv->min = get_mode_min(mode); + iv->max = get_mode_max(mode); + iv->flags = MIN_INCLUDED | MAX_INCLUDED; + break; + + default: + /* + * We do not handle UNORDERED, as a NaN + * could be included in the interval. + */ + iv->min = tarval_bad; + iv->max = tarval_bad; + iv->flags = MIN_EXCLUDED | MAX_EXCLUDED; + return NULL; + } + + if (iv->min != tarval_bad && iv->max != tarval_bad) + return iv; + return NULL; +} /* get_interval */ /** - * Try to evaluate l_iv pnc r_iv. + * Try to evaluate l_iv relation r_iv. * - * @param l_iv the left interval - * @param r_iv the right interval - * @param pnc the compare relation + * @param l_iv the left interval + * @param r_iv the right interval + * @param relation the compare relation * * @return * tarval_b_true or tarval_b_false it it can be evaluated, * tarval_bad else */ -static tarval *compare_iv(const interval_t *l_iv, const interval_t *r_iv, pn_Cmp pnc) +static ir_tarval *(compare_iv)(const interval_t *l_iv, const interval_t *r_iv, ir_relation relation) { - pn_Cmp res; - unsigned flags; - tarval *tv_true = tarval_b_true, *tv_false = tarval_b_false; - - /* if one interval contains NaNs, we cannot evaluate anything */ - if (! l_iv || ! r_iv) - return tarval_bad; - - /* we can only check ordered relations */ - if (pnc & pn_Cmp_Uo) { - tarval *t; - - pnc = get_negated_pnc(pnc); - t = tv_true; - tv_true = tv_false; - tv_false = t; - } - - /* if we have > or >=, we do the inverse to save some cases */ - if (pnc == pn_Cmp_Ge || pnc == pn_Cmp_Gt) { - const interval_t *t; - - pnc = get_inversed_pnc(pnc); - t = l_iv; - l_iv = r_iv; - r_iv = t; - } - - /* now, only the following cases remains */ - switch (pnc) { - case pn_Cmp_Eq: - /* two intervals can be compared for equality only if they are a single value */ - if (l_iv->min == l_iv->max && r_iv->min == r_iv->max) - return tarval_cmp(l_iv->min, r_iv->min) == pn_Cmp_Eq ? tv_true : tv_false; - break; - - case pn_Cmp_Lg: - /* two intervals can be compared for not equality only if they are a single value */ - if (l_iv->min == l_iv->max && r_iv->min == r_iv->max) - return tarval_cmp(l_iv->min, r_iv->min) != pn_Cmp_Eq ? tv_true : tv_false; - break; - - case pn_Cmp_Lt: - res = tarval_cmp(l_iv->max, r_iv->min); - - /* [a, b] < [c, d] <==> b < c */ - if (res == pn_Cmp_Lt) - return tv_true; - - /* if one border is excluded, b <= c is enough */ - if ((l_iv->flags & MAX_EXCLUDED || r_iv->flags & MIN_EXCLUDED) && - res == pn_Cmp_Eq) - return tv_true; - - /* [a, b] >= [c, d] <==> a > d */ - res = tarval_cmp(l_iv->min, r_iv->max); - if (res == pn_Cmp_Gt) - return tv_false; - - /* if one border is excluded, a >= d is enough */ - if ((l_iv->flags & MIN_EXCLUDED || r_iv->flags & MAX_EXCLUDED) && - res == pn_Cmp_Eq) - return tv_false; - break; - - case pn_Cmp_Le: - /* [a, b) <= [c, d] or [a, b] <= (c, d] <==> b <= c */ - flags = (l_iv->flags & MAX_EXCLUDED) | (r_iv->flags & MIN_EXCLUDED); - if (flags) { - res = tarval_cmp(l_iv->max, r_iv->min); - - if (res == pn_Cmp_Lt || res == pn_Cmp_Eq) - return tv_true; - } - - res = tarval_cmp(l_iv->min, r_iv->max); - - /* [a, b] > [c, d] <==> a > d */ - if (res == pn_Cmp_Gt) - return tv_false; - - /* if one border is excluded, a >= d is enough */ - if ((l_iv->flags & MIN_EXCLUDED || r_iv->flags & MAX_EXCLUDED) && - res == pn_Cmp_Eq) - return tv_false; - break; - - case pn_Cmp_Leg: - /* Hmm. if both are intervals, we can find an order */ - return tv_true; - - default: - return tarval_bad; - } - return tarval_bad; -} + ir_relation res; + unsigned flags; + ir_tarval *tv_true = tarval_b_true, *tv_false = tarval_b_false; + + /* if one interval contains NaNs, we cannot evaluate anything */ + if (! l_iv || ! r_iv) + return tarval_bad; + + /* we can only check ordered relations */ + if (relation & ir_relation_unordered) { + ir_tarval *t; + + relation = get_negated_relation(relation); + t = tv_true; + tv_true = tv_false; + tv_false = t; + } + + /* if we have > or >=, we do the inverse to save some cases */ + if (relation == ir_relation_greater_equal || relation == ir_relation_greater) { + const interval_t *t; + + relation = get_inversed_relation(relation); + t = l_iv; + l_iv = r_iv; + r_iv = t; + } + + /* now, only the following cases remains */ + switch (relation) { + case ir_relation_equal: + /* two intervals can be compared for equality only if they are a single value */ + if (l_iv->min == l_iv->max && r_iv->min == r_iv->max) + return tarval_cmp(l_iv->min, r_iv->min) == ir_relation_equal ? tv_true : tv_false; + + /* if both intervals do not intersect, it is never equal */ + res = tarval_cmp(l_iv->max, r_iv->min); + + /* b < c ==> [a,b] != [c,d] */ + if (res == ir_relation_less) + return tv_false; + + /* b <= c ==> [a,b) != [c,d] AND [a,b] != (c,d] */ + if ((l_iv->flags & MAX_EXCLUDED || r_iv->flags & MIN_EXCLUDED) + && (res == ir_relation_equal)) + return tv_false; + + res = tarval_cmp(r_iv->max, l_iv->min); + + /* d < a ==> [c,d] != [a,b] */ + if (res == ir_relation_less) + return tv_false; + + /* d <= a ==> [c,d) != [a,b] AND [c,d] != (a,b] */ + if ((r_iv->flags & MAX_EXCLUDED || l_iv->flags & MIN_EXCLUDED) + && (res == ir_relation_equal)) + return tv_false; + break; + + case ir_relation_less_greater: + /* two intervals can be compared for not equality only if they are a single value */ + if (l_iv->min == l_iv->max && r_iv->min == r_iv->max) + return tarval_cmp(l_iv->min, r_iv->min) != ir_relation_equal ? tv_true : tv_false; + break; + + case ir_relation_less: + res = tarval_cmp(l_iv->max, r_iv->min); + + /* [a, b] < [c, d] <==> b < c */ + if (res == ir_relation_less) + return tv_true; + + /* if one border is excluded, b <= c is enough */ + if ((l_iv->flags & MAX_EXCLUDED || r_iv->flags & MIN_EXCLUDED) && + res == ir_relation_equal) + return tv_true; + + /* [a, b] >= [c, d] <==> a > d */ + res = tarval_cmp(l_iv->min, r_iv->max); + if (res == ir_relation_greater) + return tv_false; + + /* if one border is excluded, a >= d is enough */ + if ((l_iv->flags & MIN_EXCLUDED || r_iv->flags & MAX_EXCLUDED) && + res == ir_relation_equal) + return tv_false; + break; + + case ir_relation_less_equal: + /* [a, b) <= [c, d] or [a, b] <= (c, d] <==> b <= c */ + flags = (l_iv->flags & MAX_EXCLUDED) | (r_iv->flags & MIN_EXCLUDED); + if (flags) { + res = tarval_cmp(l_iv->max, r_iv->min); + + if (res == ir_relation_less || res == ir_relation_equal) + return tv_true; + } + + res = tarval_cmp(l_iv->min, r_iv->max); + + /* [a, b] > [c, d] <==> a > d */ + if (res == ir_relation_greater) + return tv_false; + + /* if one border is excluded, a >= d is enough */ + if ((l_iv->flags & MIN_EXCLUDED || r_iv->flags & MAX_EXCLUDED) && + res == ir_relation_equal) + return tv_false; + break; + + case ir_relation_less_equal_greater: + /* Hmm. if both are intervals, we can find an order */ + return tv_true; + + default: + return tarval_bad; + } + return tarval_bad; +} /* compare_iv */ + +/** + * Returns non-zero, if a given relation is transitive. + */ +static int is_transitive(ir_relation relation) +{ + return (ir_relation_false < relation && relation < ir_relation_less_greater); +} /* is_transitive */ /** * Return the value of a Cmp if one or both predecessors * are Confirm nodes. * - * @param left the left operand of the Cmp - * @param right the right operand of the Cmp + * @param cmp the Cmp node + * @param left the left operand of the Cmp + * @param right the right operand of the Cmp + * @param relation the compare relation */ -tarval *computed_value_Cmp_Confirm(ir_node *cmp, ir_node *left, ir_node *right, pn_Cmp pnc) +ir_tarval *computed_value_Cmp_Confirm(const ir_node *cmp, ir_node *left, ir_node *right, ir_relation relation) { - ir_node *l_bound; - pn_Cmp l_pnc; - interval_t l_iv, r_iv; - tarval *tv; - - if (get_irn_op(right) == op_Confirm) { - ir_node *t; - - /* we want the Confirm on the left side */ - t = left; - left = right; - right = t; - - pnc = get_inversed_pnc(pnc); - } - else if (get_irn_op(left) != op_Confirm) { - /* no Confirm on either one side, finish */ - return tarval_bad; - } - - /* ok, here at least left is a Confirm, right might be */ - l_bound = get_Confirm_bound(left); - l_pnc = get_Confirm_cmp(left); - - if (get_irn_op(right) == op_Confirm) { - /* - * both sides are Confirm's. Check some rare cases first. - */ - ir_node *r_bound = get_Confirm_bound(right); - pn_Cmp r_pnc = get_Confirm_cmp(right); - - /* - * check for == or != can sometime be made WITHOUT constant bounds - * Beware of NaN's. - */ - if (! mode_is_float(get_irn_mode(left)) && - (pnc == pn_Cmp_Eq || pnc == pn_Cmp_Lg)) { - /* l == r if bound(l) == bound(r) AND pnc(l) == pnc(r) == '=' */ - if (r_bound == l_bound && r_pnc == l_pnc && r_pnc == pn_Cmp_Eq) { - DBG_EVAL_CONFIRM(cmp); - return pnc == pn_Cmp_Eq ? tarval_b_true : tarval_b_false; - } - - /* - * Here, we check only the right Confirm, as the left Confirms are - * checked later anyway. - */ - - if (left == r_bound && (r_pnc == pn_Cmp_Eq || r_pnc == pn_Cmp_Lg)) { - /* l == bound(r) AND pnc(r) == pnc */ - if (r_pnc == pnc) { - DBG_EVAL_CONFIRM(cmp); - return tarval_b_true; - } - /* l == bound(r) AND pnc(r) != pnc */ - else { - DBG_EVAL_CONFIRM(cmp); - return tarval_b_false; - } - } - } - - /* now, try interval magic */ - tv = compare_iv( - get_interval(&l_iv, l_bound, l_pnc), - get_interval(&r_iv, r_bound, r_pnc), - pnc); - - if (tv != tarval_bad) { - DBG_EVAL_CONFIRM(cmp); - return tv; - } - } - - /* from Here, check only left Confirm */ - - /* - * checks for == or != can sometime be made WITHOUT constant bounds - * Beware of NaN's. - */ - if (! mode_is_float(get_irn_mode(left)) && - (pnc == pn_Cmp_Eq || pnc == pn_Cmp_Lg)) { - if (right == l_bound && (l_pnc == pn_Cmp_Eq || l_pnc == pn_Cmp_Lg)) { - /* r == bound(l) AND pnc(l) == pnc */ - if (l_pnc == pnc) { - DBG_EVAL_CONFIRM(cmp); - return tarval_b_true; - } - /* r == bound(l) AND pnc(l) != pnc */ - else { - DBG_EVAL_CONFIRM(cmp); - return tarval_b_false; - } - } - } - - /* now, only right == Const can help */ - tv = value_of(right); - - if (tv != tarval_bad) { - tv = compare_iv( - get_interval(&l_iv, l_bound, l_pnc), - get_interval_from_tv(&r_iv, tv), - pnc); - } - - if (tv != tarval_bad) - DBG_EVAL_CONFIRM(cmp); - - return tv; -} + ir_node *l_bound; + ir_relation l_relation, res_relation, neg_relation; + interval_t l_iv, r_iv; + ir_tarval *tv; + + if (is_Confirm(right)) { + /* we want the Confirm on the left side */ + ir_node *t = right; + right = left; + left = t; + + relation = get_inversed_relation(relation); + } else if (! is_Confirm(left)) { + /* nothing more found */ + tv = tarval_bad; + goto check_null_case; + } + + /* ok, here at least left is a Confirm, right might be */ + l_bound = get_Confirm_bound(left); + l_relation = get_Confirm_relation(left); + + if (is_Confirm(right)) { + /* + * both sides are Confirm's. Check some rare cases first. + */ + ir_node *r_bound = get_Confirm_bound(right); + ir_relation r_relation = get_Confirm_relation(right); + + /* + * some check can be made WITHOUT constant bounds + */ + if (r_bound == l_bound) { + if (is_transitive(l_relation)) { + ir_relation r_inc_relation = get_inversed_relation(r_relation); + + /* + * triangle inequality: + * + * a CMP B && B CMP b => a CMP b, !(a ~CMP b) + * + * We handle correctly cases with some <=/>= here + */ + if ((l_relation & ~ir_relation_equal) == (r_inc_relation & ~ir_relation_equal)) { + res_relation = (l_relation & ~ir_relation_equal) | (l_relation & r_inc_relation & ir_relation_equal); + + if ((relation == res_relation) || ((relation & ~ir_relation_equal) == res_relation)) { + DBG_OUT_TR(l_relation, l_bound, r_relation, r_bound, relation, "true"); + DBG_EVAL_CONFIRM(cmp); + return tarval_b_true; + } else { + ir_relation neg_relation = get_negated_relation(relation); + + if ((neg_relation == res_relation) || ((neg_relation & ~ir_relation_equal) == res_relation)) { + DBG_OUT_TR(l_relation, l_bound, r_relation, r_bound, relation, "false"); + DBG_EVAL_CONFIRM(cmp); + return tarval_b_false; + } + } + } + } + } + + /* + * Here, we check only the right Confirm, as the left Confirms are + * checked later anyway. + */ + if (left == r_bound) { + /* + * l == bound(r) AND relation(r) == relation: + * + * We know that a CMP b and check for that + */ + if ((r_relation == relation) || (r_relation == (relation & ~ir_relation_equal))) { + DBG_OUT_R(r_relation, r_bound, left, relation, right, "true"); + DBG_EVAL_CONFIRM(cmp); + return tarval_b_true; + } + /* + * l == bound(r) AND relation(r) != relation: + * + * We know that a CMP b and check for a ~CMP b + */ + else { + neg_relation = get_negated_relation(relation); + + if ((r_relation == neg_relation) || (r_relation == (neg_relation & ~ir_relation_equal))) { + DBG_OUT_R(r_relation, r_bound, left, relation, right, "false"); + DBG_EVAL_CONFIRM(cmp); + return tarval_b_false; + } + } + } + + /* now, try interval magic */ + tv = compare_iv( + get_interval(&l_iv, l_bound, l_relation), + get_interval(&r_iv, r_bound, r_relation), + relation); + + if (tv != tarval_bad) { + DBG_EVAL_CONFIRM(cmp); + return tv; + } + } + + /* from Here, check only left Confirm */ + + /* + * some checks can be made WITHOUT constant bounds + */ + if (right == l_bound) { + /* + * r == bound(l) AND relation(l) == relation: + * + * We know that a CMP b and check for that + */ + if ((l_relation == relation) || (l_relation == (relation & ~ir_relation_equal))) { + DBG_OUT_L(l_relation, l_bound, left, relation, right, "true"); + DBG_EVAL_CONFIRM(cmp); + return tarval_b_true; + } + /* + * r == bound(l) AND relation(l) is Not(relation): + * + * We know that a CMP b and check for a ~CMP b + */ + else { + neg_relation = get_negated_relation(relation); + + if ((l_relation == neg_relation) || (l_relation == (neg_relation & ~ir_relation_equal))) { + DBG_OUT_L(l_relation, l_bound, left, relation, right, "false"); + DBG_EVAL_CONFIRM(cmp); + return tarval_b_false; + } + } + } + + /* now, only right == Const can help */ + tv = value_of(right); + + if (tv != tarval_bad) { + tv = compare_iv( + get_interval(&l_iv, l_bound, l_relation), + get_interval_from_tv(&r_iv, tv), + relation); + } else { +check_null_case: + /* check some other cases */ + if ((relation == ir_relation_equal || relation == ir_relation_less_greater) && + is_Const(right) && is_Const_null(right)) { + /* for == 0 or != 0 we have some special tools */ + ir_mode *mode = get_irn_mode(left); + const ir_node *dummy; + if (mode_is_reference(mode)) { + if (value_not_null(left, &dummy)) { + tv = relation == ir_relation_equal ? tarval_b_false : tarval_b_true; + } + } else { + if (value_not_zero(left, &dummy)) { + tv = relation == ir_relation_equal ? tarval_b_false : tarval_b_true; + } + } + } + } + + if (tv != tarval_bad) + DBG_EVAL_CONFIRM(cmp); + + return tv; +} /* computed_value_Cmp_Confirm */ + +#ifdef DEBUG_CONFIRM +/** + * For debugging. Prints an interval into a string. + * + * @param buf address of a string buffer + * @param len length of the string buffer + * @param iv the interval + */ +static int iv_snprintf(char *buf, size_t len, const interval_t *iv) +{ + char smin[64], smax[64]; + + if (iv) { + tarval_snprintf(smin, sizeof(smin), iv->min); + + if (iv->min != iv->max || (iv->flags & (MIN_EXCLUDED|MAX_EXCLUDED))) { + tarval_snprintf(smax, sizeof(smax), iv->max); + + return snprintf(buf, len, "%c%s, %s%c", + iv->flags & MIN_EXCLUDED ? '(' : '[', + smin, smax, + iv->flags & MAX_EXCLUDED ? ')' : ']' + ); + } else + return snprintf(buf, len, "%s", smin); + } + return snprintf(buf, len, ""); +} /* iv_snprintf */ + +/** + * For debugging. Prints an interval compare. + * + * @param l_iv the left interval + * @param r_iv the right interval + * @param relation the compare relation + */ +static void print_iv_cmp(const interval_t *l_iv, const interval_t *r_iv, ir_relation relation) +{ + char sl[128], sr[128]; + + iv_snprintf(sl, sizeof(sl), l_iv); + iv_snprintf(sr, sizeof(sr), r_iv); + + ir_printf("%s %= %s", sl, relation, sr); +} /* print_iv_cmp */ + +/** + * For debugging. call *compare_iv() and prints inputs and result. + * + * @param l_iv the left interval + * @param r_iv the right interval + * @param relation the compare relation + */ +static tarval *compare_iv_dbg(const interval_t *l_iv, const interval_t *r_iv, ir_relation relation) +{ + tarval *tv = (compare_iv)(l_iv, r_iv, relation); + + if (tv == tarval_bad) + return tv; + + ir_printf("In %e:\n", get_irg_entity(current_ir_graph)); + print_iv_cmp(l_iv, r_iv, relation); + ir_printf(" = %T\n", tv); + return tv; +} /* compare_iv_dbg */ + +#endif /* DEBUG_CONFIRM */