X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fopt%2Fopt_confirms.c;h=3fd45f768f0468c62ef7ba4b9e5fa16ba60dd720;hb=a63ae9728ba0fbe891a2bb6c291c41b0e618af62;hp=6dac95cf1ce1ee5d2f7383e654fc64edbae421db;hpb=a58c9d774111216a4d9a8a7d34e039d83a66dbe3;p=libfirm diff --git a/ir/opt/opt_confirms.c b/ir/opt/opt_confirms.c index 6dac95cf1..3fd45f768 100644 --- a/ir/opt/opt_confirms.c +++ b/ir/opt/opt_confirms.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. * @@ -23,9 +23,7 @@ * @author Michael Beck * @version $Id$ */ -#ifdef HAVE_CONFIG_H -# include "config.h" -#endif +#include "config.h" #undef DEBUG_CONFIRM @@ -97,34 +95,24 @@ static tarval *compare_iv_dbg(const interval_t *l_iv, const interval_t *r_iv, pn * This is a often needed case, so we handle here Confirm * nodes too. */ -int value_not_zero(ir_node *blk, ir_node *n, ir_node **confirm) { +int value_not_zero(const ir_node *n, ir_node_cnst_ptr *confirm) { #define RET_ON(x) if (x) { *confirm = n; return 1; }; break tarval *tv; ir_mode *mode = get_irn_mode(n); pn_Cmp pnc; - if (get_irg_pinned(get_irn_irg(blk)) != op_pin_state_pinned) - blk = NULL; - *confirm = NULL; /* there might be several Confirms one after other that form an interval */ - for (; is_Confirm(n); n = get_Confirm_value(n)) { - unsigned long region = get_Confirm_region(n); - - /* check if it's legal to use this confirm. */ - if (region != 0) { - ir_node *curr_blk = get_irn_n(n, -1); - - /* this confirm is bound to a region. */ - if (! blk) - continue; - - if (get_Block_exc_region(curr_blk) != region) - continue; - /* all went fine, the current Confirm belongs to the same region */ + for (;;) { + if (is_Minus(n) || is_Abs(n)) { + /* we can safely skip Minus and Abs when checking for != 0 */ + n = get_unop_op(n); + continue; } + if (! is_Confirm(n)) + break; /* * Note: A Confirm is never after a Const. So, @@ -161,6 +149,7 @@ int value_not_zero(ir_node *blk, ir_node *n, ir_node **confirm) { default: break; } + n = get_Confirm_value(n); } tv = value_of(n); @@ -184,51 +173,40 @@ int value_not_zero(ir_node *blk, ir_node *n, ir_node **confirm) { * - A SymConst(entity) is NEVER a NULL pointer * - Confirms are evaluated */ -int value_not_null(ir_node *blk, ir_node *n, ir_node **confirm) { - ir_op *op; +int value_not_null(const ir_node *n, ir_node_cnst_ptr *confirm) { + tarval *tv; - if (get_irg_pinned(get_irn_irg(blk)) != op_pin_state_pinned) - blk = NULL; *confirm = NULL; - n = skip_Cast(n); + n = skip_Cast_const(n); + + tv = value_of(n); + if (tarval_is_constant(tv) && ! tarval_is_null(tv)) + return 1; - op = get_irn_op(n); assert(mode_is_reference(get_irn_mode(n))); if (get_opt_sel_based_null_check_elim()) { /* skip all Sel nodes and Cast's */ - while (op == op_Sel) { + while (is_Sel(n)) { n = skip_Cast(get_Sel_ptr(n)); - op = get_irn_op(n); } } - if (op == op_SymConst && get_SymConst_kind(n) == symconst_addr_ent) + if (is_Global(n)) { + /* global references are never NULL */ + return 1; + } else if (n == get_irg_frame(current_ir_graph)) { + /* local references are never NULL */ return 1; - if (op == op_Const) { - tarval *tv = get_Const_tarval(n); - - if (tv != tarval_bad && classify_tarval(tv) != TV_CLASSIFY_NULL) - return 1; } else { + /* check for more Confirms */ for (; is_Confirm(n); n = skip_Cast(get_Confirm_value(n))) { - unsigned long region = get_Confirm_region(n); + if (get_Confirm_cmp(n) == pn_Cmp_Lg) { + ir_node *bound = get_Confirm_bound(n); + tarval *tv = value_of(bound); - /* check if it's legal to use this confirm. */ - if (region != 0) { - ir_node *curr_blk = get_irn_n(n, -1); - - /* this confirm is bound to a region. */ - if (! blk) - continue; - - if (get_Block_exc_region(curr_blk) != region) - continue; - /* all went fine, the current Confirm belongs to the same region */ - } - - if (get_Confirm_cmp(n) == pn_Cmp_Lg && - classify_Const(get_Confirm_bound(n)) == CNST_NULL) { + if (tarval_is_null(tv)) { *confirm = n; return 1; + } } } } @@ -244,8 +222,24 @@ value_classify_sign classify_value_sign(ir_node *n) { tarval *tv, *c; ir_mode *mode; pn_Cmp cmp, ncmp; + int negate = 1; - if (get_irn_op(n) != op_Confirm) + for (;;) { + ir_opcode 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)); @@ -287,7 +281,7 @@ value_classify_sign classify_value_sign(ir_node *n) { return value_classified_unknown; /* yep, negative */ - return value_classified_negative; + return value_classified_negative * negate; case pn_Cmp_Ge: /* @@ -318,7 +312,7 @@ value_classify_sign classify_value_sign(ir_node *n) { } /* yep, positive */ - return value_classified_positive; + return value_classified_positive * negate; default: return value_classified_unknown; @@ -608,26 +602,6 @@ static int is_transitive(pn_Cmp pnc) { return (pn_Cmp_False < pnc && pnc < pn_Cmp_Lg); } /* is_transitive */ -/** - * returns a confirm node starting from n that is allowed to be used in the exception - * region. - * - * @param blk the block of the region - * @param n the node - */ -static ir_node *get_allowed_confirm(ir_node *blk, ir_node *n) { - for (; is_Confirm(n); n = get_Confirm_value(n)) { - ir_exc_region_t reg = get_Confirm_region(n); - - if (reg == 0 || (blk != NULL && reg == get_Block_exc_region(blk))) { - /* found an allowed Confirm */ - return n; - } - - } - return NULL; -} /* get_allowed_confirm */ - /** * Return the value of a Cmp if one or both predecessors * are Confirm nodes. @@ -638,29 +612,23 @@ static ir_node *get_allowed_confirm(ir_node *blk, ir_node *n) { * @param pnc the compare relation */ tarval *computed_value_Cmp_Confirm(ir_node *cmp, ir_node *left, ir_node *right, pn_Cmp pnc) { - ir_node *l_bound, *confirm; + ir_node *l_bound; pn_Cmp l_pnc, res_pnc, neg_pnc; interval_t l_iv, r_iv; tarval *tv; ir_mode *mode; - ir_node *blk; - - /* beware, Cmp is not pinned. */ - blk = get_irn_n(cmp, -1); - if (get_irg_pinned(get_Block_irg(blk)) != op_pin_state_pinned) - blk = NULL; - if ((confirm = get_allowed_confirm(blk, right)) != NULL) { + if (is_Confirm(right)) { /* we want the Confirm on the left side */ + ir_node *t = right; right = left; - left = confirm; + left = t; pnc = get_inversed_pnc(pnc); - } else if ((confirm = get_allowed_confirm(blk, left)) != NULL) { - left = confirm; - } else { - /* no Confirm on either one side, finish */ - return tarval_bad; + } 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 */ @@ -793,6 +761,24 @@ tarval *computed_value_Cmp_Confirm(ir_node *cmp, ir_node *left, ir_node *right, get_interval(&l_iv, l_bound, l_pnc), get_interval_from_tv(&r_iv, tv), pnc); + } else { +check_null_case: + /* check some other cases */ + if ((pnc == pn_Cmp_Eq || pnc == pn_Cmp_Lg) && + 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 = pnc == pn_Cmp_Eq ? tarval_b_false : tarval_b_true; + } + } else { + if (value_not_zero(left, &dummy)) { + tv = pnc == pn_Cmp_Eq ? tarval_b_false : tarval_b_true; + } + } + } } if (tv != tarval_bad)