From e3a4bae9ccfa8ff79e4bdd07e016f85291c8ae76 Mon Sep 17 00:00:00 2001 From: Matthias Braun Date: Thu, 24 Mar 2011 17:48:24 +0100 Subject: [PATCH] fix lower_d lowering Cmps too realy resulting in unnecessary 0/1 production --- ir/lower/lower_dw.c | 107 ++++++++++++++++++++++++++++++-------------- 1 file changed, 73 insertions(+), 34 deletions(-) diff --git a/ir/lower/lower_dw.c b/ir/lower/lower_dw.c index c3460e660..c5b379275 100644 --- a/ir/lower/lower_dw.c +++ b/ir/lower/lower_dw.c @@ -138,6 +138,8 @@ struct lower_env_t { ir_type *value_param_tp; /**< the old value param type */ }; +static void lower_node(lower_env_t *env, ir_node *node); + /** * Create a method type for a Conv emulation from imode to omode. */ @@ -980,6 +982,25 @@ static void lower_Not(ir_node *node, ir_mode *mode, lower_env_t *env) set_lowered(env, node, res_low, res_high); } +static bool is_cmp_0_equality(ir_node *cmp) +{ + ir_relation relation = get_Cmp_relation(cmp); + ir_node *right = get_Cmp_right(cmp); + ir_node *left = get_Cmp_right(cmp); + ir_mode *mode = get_irn_mode(left); + /* assume constants are normalized to the right side */ + if (!is_Const(right) || !is_Const_null(right)) + return false; + /* assume unordered bites have been optimized away */ + if (relation == ir_relation_equal) + return true; + if (mode_is_signed(mode) && relation == ir_relation_less_greater) + return true; + if (relation == ir_relation_greater) + return true; + return false; +} + /** * Translate a Cond. */ @@ -1005,18 +1026,25 @@ static void lower_Cond(ir_node *node, ir_mode *mode, lower_env_t *env) /* bad we can't really handle Switch with 64bit offsets */ panic("Cond with 64bit jumptable not supported"); } + lower_node(env, sel); return; } - if (!is_Cmp(sel)) + if (!is_Cmp(sel)) { + lower_node(env, sel); return; + } left = get_Cmp_left(sel); cmp_mode = get_irn_mode(left); - if (cmp_mode != env->high_signed && cmp_mode != env->high_unsigned) + if (cmp_mode != env->high_signed && cmp_mode != env->high_unsigned) { + lower_node(env, sel); return; + } right = get_Cmp_right(sel); + lower_node(env, left); + lower_node(env, right); lentry = get_node_entry(env, left); rentry = get_node_entry(env, right); @@ -1043,17 +1071,15 @@ static void lower_Cond(ir_node *node, ir_mode *mode, lower_env_t *env) dbg = get_irn_dbg_info(sel); relation = get_Cmp_relation(sel); - if (is_Const(right) && is_Const_null(right)) { - if (relation == ir_relation_equal || relation == ir_relation_less_greater) { - /* x ==/!= 0 ==> or(low,high) ==/!= 0 */ - ir_mode *mode = env->low_unsigned; - ir_node *low = new_r_Conv(block, lentry->low_word, mode); - ir_node *high = new_r_Conv(block, lentry->high_word, mode); - ir_node *ornode = new_rd_Or(dbg, block, low, high, mode); - ir_node *cmp = new_rd_Cmp(dbg, block, ornode, new_r_Const_long(irg, mode, 0), relation); - set_Cond_selector(node, cmp); - return; - } + if (is_cmp_0_equality(sel)) { + /* x ==/!= 0 ==> or(low,high) ==/!= 0 */ + ir_mode *mode = env->low_unsigned; + ir_node *low = new_r_Conv(block, lentry->low_word, mode); + ir_node *high = new_r_Conv(block, lentry->high_word, mode); + ir_node *ornode = new_rd_Or(dbg, block, low, high, mode); + ir_node *cmp = new_rd_Cmp(dbg, block, ornode, new_r_Const_long(irg, mode, 0), relation); + set_Cond_selector(node, cmp); + return; } if (relation == ir_relation_equal) { @@ -1296,47 +1322,58 @@ static void lower_Cmp(ir_node *cmp, ir_mode *m, lower_env_t *env) ir_mode *mode = get_irn_mode(l); ir_node *r, *low, *high, *t, *res; ir_relation relation; - ir_node *blk; - dbg_info *db; + ir_node *block; + dbg_info *dbg; const node_entry_t *lentry; const node_entry_t *rentry; (void) m; - if (mode != env->high_signed && mode != env->high_unsigned) { + if (mode != env->high_signed && mode != env->high_unsigned) return; - } r = get_Cmp_right(cmp); lentry = get_node_entry(env, l); rentry = get_node_entry(env, r); relation = get_Cmp_relation(cmp); - blk = get_nodes_block(cmp); - db = get_irn_dbg_info(cmp); + block = get_nodes_block(cmp); + dbg = get_irn_dbg_info(cmp); + + /* easy case for x ==/!= 0 (see lower_Cond for details) */ + if (ir_is_equality_cmp_0(cmp)) { + ir_graph *irg = get_irn_irg(cmp); + ir_mode *mode = env->low_unsigned; + ir_node *low = new_r_Conv(block, lentry->low_word, mode); + ir_node *high = new_r_Conv(block, lentry->high_word, mode); + ir_node *ornode = new_rd_Or(dbg, block, low, high, mode); + ir_node *new_cmp = new_rd_Cmp(dbg, block, ornode, new_r_Const_long(irg, mode, 0), relation); + exchange(cmp, new_cmp); + return; + } if (relation == ir_relation_equal) { /* simple case:a == b <==> a_h == b_h && a_l == b_l */ - low = new_rd_Cmp(db, blk, lentry->low_word, rentry->low_word, + low = new_rd_Cmp(dbg, block, lentry->low_word, rentry->low_word, relation); - high = new_rd_Cmp(db, blk, lentry->high_word, rentry->high_word, + high = new_rd_Cmp(dbg, block, lentry->high_word, rentry->high_word, relation); - res = new_rd_And(db, blk, low, high, mode_b); + res = new_rd_And(dbg, block, low, high, mode_b); } else if (relation == ir_relation_less_greater) { /* simple case:a != b <==> a_h != b_h || a_l != b_l */ - low = new_rd_Cmp(db, blk, lentry->low_word, rentry->low_word, + low = new_rd_Cmp(dbg, block, lentry->low_word, rentry->low_word, relation); - high = new_rd_Cmp(db, blk, lentry->high_word, rentry->high_word, + high = new_rd_Cmp(dbg, block, lentry->high_word, rentry->high_word, relation); - res = new_rd_Or(db, blk, low, high, mode_b); + res = new_rd_Or(dbg, block, low, high, mode_b); } else { /* a rel b <==> a_h REL b_h || (a_h == b_h && a_l rel b_l) */ - ir_node *high1 = new_rd_Cmp(db, blk, lentry->high_word, + ir_node *high1 = new_rd_Cmp(dbg, block, lentry->high_word, rentry->high_word, relation & ~ir_relation_equal); - low = new_rd_Cmp(db, blk, lentry->low_word, rentry->low_word, + low = new_rd_Cmp(dbg, block, lentry->low_word, rentry->low_word, relation); - high = new_rd_Cmp(db, blk, lentry->high_word, rentry->high_word, + high = new_rd_Cmp(dbg, block, lentry->high_word, rentry->high_word, ir_relation_equal); - t = new_rd_And(db, blk, low, high, mode_b); - res = new_rd_Or(db, blk, high1, t, mode_b); + t = new_rd_And(dbg, block, low, high, mode_b); + res = new_rd_Or(dbg, block, high1, t, mode_b); } exchange(cmp, res); } @@ -2152,10 +2189,12 @@ static void lower_node(lower_env_t *env, ir_node *node) lower_node(env, block); } - arity = get_irn_arity(node); - for (i = 0; i < arity; ++i) { - ir_node *pred = get_irn_n(node, i); - lower_node(env, pred); + if (!is_Cond(node)) { + arity = get_irn_arity(node); + for (i = 0; i < arity; ++i) { + ir_node *pred = get_irn_n(node, i); + lower_node(env, pred); + } } op = get_irn_op(node); -- 2.20.1