Add ALLOCAN() and ALLOCANZ().
[libfirm] / ir / lower / lower_mode_b.c
index dfd502c..c10118a 100644 (file)
@@ -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.
  *
 
 /**
  * @file
+ * @brief       lowers operations with mode_b. The result is a graph which
+ *              might still contains some convs from/to mode_b, but no
+ *              operations are performed on them anymore, they are just there
+ *              so modes match. A backend can safely skip all mode_b convs.
  * @author      Matthias Braun, Christoph Mallon
  * @version     $Id$
  */
-#ifdef HAVE_CONFIG_H
 #include "config.h"
-#endif
 
 #include <stdlib.h>
 
 #include "ircons_t.h"
 #include "irgwalk.h"
 #include "irtools.h"
+#include "iredges.h"
+#include "iropt_t.h"
 #include "tv.h"
 #include "error.h"
 #include "lowering.h"
+#include "pdeq.h"
 
-static ir_mode *lowered_mode     = NULL;
-static int      lower_direct_cmp = 0;
+static lower_mode_b_config_t  config;
+static ir_type               *lowered_type  = NULL;
+static pdeq                  *lowered_nodes = NULL;
+
+/**
+ * Removes a node if its out-edge count has reached 0.
+ * temporary hack until we have proper automatic dead code elimination.
+ */
+static void maybe_kill_node(ir_node *node)
+{
+       ir_graph *irg;
+       int       i, arity;
+
+       if(get_irn_n_edges(node) != 0)
+               return;
+
+       irg = get_irn_irg(node);
+
+       assert(!is_Bad(node));
+
+       arity = get_irn_arity(node);
+       for (i = 0; i < arity; ++i) {
+               set_irn_n(node, i, new_Bad());
+       }
+       set_nodes_block(node, new_Bad());
+
+       edges_node_deleted(node, irg);
+}
 
 static ir_node *create_not(dbg_info *dbgi, ir_node *node)
 {
        ir_graph *irg    = current_ir_graph;
        ir_node  *block  = get_nodes_block(node);
-       tarval   *tv_one = get_tarval_one(lowered_mode);
-       ir_node  *one    = new_d_Const(dbgi, lowered_mode, tv_one);
+       ir_mode  *mode   = config.lowered_mode;
+       tarval   *tv_one = get_tarval_one(mode);
+       ir_node  *one    = new_d_Const(dbgi, mode, tv_one);
 
-       return new_rd_Eor(dbgi, irg, block, node, one, lowered_mode);
+       return new_rd_Eor(dbgi, irg, block, node, one, mode);
+}
+
+static ir_node *create_convb(ir_node *node)
+{
+       ir_graph *irg   = current_ir_graph;
+       ir_node  *block = get_nodes_block(node);
+       ir_node  *conv  = new_rd_Conv(NULL, irg, block, node, mode_b);
+
+       return conv;
+}
+
+static ir_type *create_lowered_type(void)
+{
+       if(lowered_type == NULL) {
+               lowered_type = new_type_primitive(new_id_from_str("__lowered_mode_b"),
+                                                 config.lowered_mode);
+       }
+       return lowered_type;
+}
+
+/**
+ * creates a "set" node that produces a 0 or 1 based on a Cmp result
+ */
+static ir_node *create_set(ir_node *node)
+{
+       ir_graph *irg     = current_ir_graph;
+       dbg_info *dbgi    = get_irn_dbg_info(node);
+       ir_mode  *mode    = config.lowered_set_mode;
+       tarval   *tv_one  = get_tarval_one(mode);
+       ir_node  *one     = new_d_Const(dbgi, mode, tv_one);
+       ir_node  *block   = get_nodes_block(node);
+       tarval   *tv_zero = get_tarval_null(mode);
+       ir_node  *zero    = new_d_Const(dbgi, mode, tv_zero);
+
+       ir_node *set      = new_rd_Mux(dbgi, irg, block, node, zero, one, mode);
+
+       if (mode != config.lowered_mode) {
+               set = new_r_Conv(irg, block, set, config.lowered_mode);
+       }
+
+       return set;
+}
+
+static void adjust_method_type(ir_type *method_type)
+{
+       int i;
+       int n_params;
+       int n_res;
+
+       n_params = get_method_n_params(method_type);
+       for(i = 0; i < n_params; ++i) {
+               ir_type *param = get_method_param_type(method_type, i);
+               if(get_type_mode(param) == mode_b) {
+                       set_method_param_type(method_type, i, create_lowered_type());
+               }
+       }
+
+       n_res = get_method_n_ress(method_type);
+       for(i = 0; i < n_res; ++i) {
+               ir_type *res_type = get_method_res_type(method_type, i);
+               if(get_type_mode(res_type) == mode_b) {
+                       set_method_res_type(method_type, i, create_lowered_type());
+               }
+       }
 }
 
 static ir_node *lower_node(ir_node *node)
 {
        ir_graph *irg   = current_ir_graph;
        dbg_info *dbgi  = get_irn_dbg_info(node);
-       ir_op    *op    = get_irn_op(node);
        ir_node  *block = get_nodes_block(node);
+       ir_mode *mode   = config.lowered_mode;
        ir_node  *res;
 
        assert(get_irn_mode(node) == mode_b);
@@ -64,20 +160,21 @@ static ir_node *lower_node(ir_node *node)
                return res;
 
        /* TODO: be robust against phi-loops... */
-       if(op == op_Phi) {
+       switch (get_irn_opcode(node)) {
+       case iro_Phi: {
                int       i, arity;
                ir_node **in;
-               ir_node  *unknown;
+               ir_node  *unknown, *new_phi;
 
-               arity = get_irn_arity(node);
-               in    = alloca(arity * sizeof(in[0]));
-               unknown = new_Unknown(lowered_mode);
+               arity   = get_irn_arity(node);
+               in      = ALLOCAN(ir_node*, arity);
+               unknown = new_Unknown(config.lowered_mode);
                for(i = 0; i < arity; ++i) {
                        in[i] = unknown;
                }
-               ir_node *new_phi = new_rd_Phi(dbgi, irg, block, arity, in,
-                                             lowered_mode);
+               new_phi = new_r_Phi(irg, block, arity, in, config.lowered_mode);
                set_irn_link(node, new_phi);
+               pdeq_putr(lowered_nodes, node);
 
                for(i = 0; i < arity; ++i) {
                        ir_node *in     = get_irn_n(node, i);
@@ -89,7 +186,9 @@ static ir_node *lower_node(ir_node *node)
                return new_phi;
        }
 
-       if(op == op_And || op == op_Or || op == op_Eor) {
+       case iro_And:
+       case iro_Or:
+       case iro_Eor: {
                int i, arity;
                ir_node *copy = exact_copy(node);
 
@@ -100,73 +199,67 @@ static ir_node *lower_node(ir_node *node)
 
                        set_irn_n(copy, i, low_in);
                }
-               set_irn_mode(copy, lowered_mode);
+               set_irn_mode(copy, config.lowered_mode);
 
                set_irn_link(node, copy);
+               pdeq_putr(lowered_nodes, node);
                return copy;
        }
-       if(op == op_Not) {
+       case iro_Not: {
                ir_node *op     = get_Not_op(node);
                ir_node *low_op = lower_node(op);
 
                res = create_not(dbgi, low_op);
                set_irn_link(node, res);
+               pdeq_putr(lowered_nodes, node);
                return res;
        }
-       if(op == op_Psi) {
-               ir_node *cond        = get_Psi_cond(node, 0);
+       case iro_Mux: {
+               ir_node *cond        = get_Mux_sel(node);
                ir_node *low_cond    = lower_node(cond);
-               ir_node *v_true      = get_Psi_val(node, 0);
+               ir_node *v_true      = get_Mux_true(node);
                ir_node *low_v_true  = lower_node(v_true);
-               ir_node *v_false     = get_Psi_default(node);
+               ir_node *v_false     = get_Mux_false(node);
                ir_node *low_v_false = lower_node(v_false);
 
-               ir_node *and0     = new_rd_And(dbgi, irg, block, cond, low_v_true,
-                                              lowered_mode);
-
+               ir_node *and0     = new_rd_And(dbgi, irg, block, low_cond, low_v_true, mode);
                ir_node *not_cond = create_not(dbgi, low_cond);
-
-               ir_node *and1     = new_rd_And(dbgi, irg, block, not_cond, low_v_false,
-                                              lowered_mode);
-
-               ir_node *or       = new_rd_Or(dbgi, irg, block, and0, and1,
-                                             lowered_mode);
+               ir_node *and1     = new_rd_And(dbgi, irg, block, not_cond, low_v_false, mode);
+               ir_node *or       = new_rd_Or(dbgi, irg, block, and0, and1, mode);
 
                set_irn_link(node, or);
+               pdeq_putr(lowered_nodes, node);
                return or;
        }
-       if(op == op_Conv) {
-               tarval  *tv_one   = get_tarval_one(lowered_mode);
-               ir_node *one      = new_d_Const(dbgi, lowered_mode, tv_one);
-               tarval  *tv_zero  = get_tarval_null(lowered_mode);
-               ir_node *zero     = new_d_Const(dbgi, lowered_mode, tv_zero);
-               ir_mode *mode     = get_irn_mode(node);
+       case iro_Conv: {
+               ir_node *pred     = get_Conv_op(node);
+               ir_mode *mode     = get_irn_mode(pred);
                tarval  *tv_zeroc = get_tarval_null(mode);
                ir_node *zero_cmp = new_d_Const(dbgi, mode, tv_zeroc);
+               ir_node *set;
 
-               ir_node *cmp      = new_rd_Cmp(dbgi, irg, block, node, zero_cmp);
+               ir_node *cmp      = new_rd_Cmp(dbgi, irg, block, pred, zero_cmp);
                ir_node *proj     = new_rd_Proj(dbgi, irg, block, cmp, mode_b,
                                                pn_Cmp_Lg);
-               ir_node *vals[2]  = { one, zero };
-               ir_node *psi      = new_rd_Psi(dbgi, irg, block, 1, &proj, vals,
-                                              lowered_mode);
+               set = create_set(proj);
 
-               set_irn_link(node, psi);
-               return psi;
+               set_irn_link(node, set);
+               pdeq_putr(lowered_nodes, node);
+               return set;
        }
-       if(op == op_Proj) {
-               ir_node *pred  = get_Proj_pred(node);
+       case iro_Proj: {
+               ir_node *pred = get_Proj_pred(node);
 
-               assert(!is_Load(pred));
                if(is_Cmp(pred)) {
-                       ir_mode *mode  = get_irn_mode(pred);
                        ir_node *left  = get_Cmp_left(pred);
                        ir_node *right = get_Cmp_right(pred);
+                       ir_mode *cmp_mode  = get_irn_mode(left);
+                       ir_node *set;
 
-                       if( (mode_is_int(mode) || mode_is_character(mode)
-                                               || mode_is_reference(mode)) &&
-                               (get_mode_size_bits(mode) < get_mode_size_bits(lowered_mode)
-                                || classify_Const(right) == CNST_NULL)) {
+                       if ((mode_is_int(cmp_mode) || mode_is_reference(cmp_mode)) && (
+                                               get_mode_size_bits(cmp_mode) < get_mode_size_bits(mode) ||
+                                               (mode_is_signed(cmp_mode) && is_Const(right) && is_Const_null(right))
+                                       )) {
                                int      pnc      = get_Proj_proj(node);
                                int      need_not = 0;
                                ir_node *a        = NULL;
@@ -177,7 +270,7 @@ static ir_node *lower_node(ir_node *node)
                                        a = left;
                                        b = right;
                                } else if(pnc == pn_Cmp_Le) {
-                                       /* a <= b  -> ((a - b) >> 31) ^ 1 */
+                                       /* a <= b  -> ~(a - b) >> 31 */
                                        a        = right;
                                        b        = left;
                                        need_not = 1;
@@ -186,81 +279,80 @@ static ir_node *lower_node(ir_node *node)
                                        a = right;
                                        b = left;
                                } else if(pnc == pn_Cmp_Ge) {
-                                       /* a >= b   -> ((a - b) >> 31) ^ 1 */
+                                       /* a >= b   -> ~(a - b) >> 31 */
                                        a        = left;
                                        b        = right;
                                        need_not = 1;
                                }
 
                                if(a != NULL) {
-                                       tarval  *tv        = new_tarval_from_long(31, mode_Iu);
+                                       int      bits      = get_mode_size_bits(mode);
+                                       tarval  *tv        = new_tarval_from_long(bits-1, mode_Iu);
                                        ir_node *shift_cnt = new_d_Const(dbgi, mode_Iu, tv);
 
-                                       if(mode != lowered_mode) {
-                                               a = new_rd_Conv(dbgi, irg, block, a, lowered_mode);
-                                               b = new_rd_Conv(dbgi, irg, block, b, lowered_mode);
+                                       if(cmp_mode != mode) {
+                                               a = new_rd_Conv(dbgi, irg, block, a, mode);
+                                               b = new_rd_Conv(dbgi, irg, block, b, mode);
                                        }
 
-                                       res = new_rd_Sub(dbgi, irg, block, a, b, lowered_mode);
-                                       res = new_rd_Shr(dbgi, irg, block, res, shift_cnt,
-                                                        lowered_mode);
-
+                                       res = new_rd_Sub(dbgi, irg, block, a, b, mode);
                                        if(need_not) {
-                                               res = create_not(dbgi, res);
+                                               res = new_rd_Not(dbgi, irg, block, res, mode);
                                        }
+                                       res = new_rd_Shr(dbgi, irg, block, res, shift_cnt, mode);
+
                                        set_irn_link(node, res);
+                                       pdeq_putr(lowered_nodes, node);
                                        return res;
                                }
                        }
 
-                       {
                        /* synthesize the 0/1 value */
-                       tarval  *tv_one  = get_tarval_one(lowered_mode);
-                       ir_node *one     = new_d_Const(dbgi, lowered_mode, tv_one);
-                       tarval  *tv_zero = get_tarval_null(lowered_mode);
-                       ir_node *zero    = new_d_Const(dbgi, lowered_mode, tv_zero);
-
-                       ir_node *vals[2] = { one, zero };
-                       ir_node *psi     = new_rd_Psi(dbgi, irg, block, 1, &node, vals,
-                                                     lowered_mode);
-
-                       set_irn_link(node, psi);
-                       return psi;
-                       }
+                       set = create_set(node);
+                       set_irn_link(node, set);
+                       pdeq_putr(lowered_nodes, node);
+                       return set;
+               } else if(is_Proj(pred) && is_Call(get_Proj_pred(pred))) {
+                       ir_type   *type   = get_Call_type(get_Proj_pred(pred));
+                       adjust_method_type(type);
+                       set_irn_mode(node, mode);
+                       return node;
+               } else if(is_Proj(pred) && is_Start(get_Proj_pred(pred))) {
+                       ir_entity *entity = get_irg_entity(irg);
+                       ir_type   *type   = get_entity_type(entity);
+                       adjust_method_type(type);
+                       set_irn_mode(node, mode);
+                       return node;
                }
 
                panic("unexpected projb: %+F (pred: %+F)", node, pred);
        }
-       if(op == op_Const) {
+       case iro_Const: {
                tarval *tv = get_Const_tarval(node);
                if(tv == get_tarval_b_true()) {
-                       tarval  *tv_one  = get_tarval_one(lowered_mode);
-                       res              = new_d_Const(dbgi, lowered_mode, tv_one);
+                       tarval  *tv_one  = get_tarval_one(mode);
+                       res              = new_d_Const(dbgi, mode, tv_one);
                } else if(tv == get_tarval_b_false()) {
-                       tarval  *tv_zero = get_tarval_null(lowered_mode);
-                       res              = new_d_Const(dbgi, lowered_mode, tv_zero);
+                       tarval  *tv_zero = get_tarval_null(mode);
+                       res              = new_d_Const(dbgi, mode, tv_zero);
                } else {
                        panic("invalid boolean const %+F", node);
                }
                set_irn_link(node, res);
+               pdeq_putr(lowered_nodes, node);
                return res;
        }
-
-       panic("didn't expect %+F to have mode_b", node);
-}
-
-static ir_node *create_convb(ir_node *node)
-{
-       ir_graph *irg   = current_ir_graph;
-       ir_node  *block = get_nodes_block(node);
-       ir_node  *conv  = new_rd_Conv(NULL, irg, block, node, mode_b);
-
-       return conv;
+       case iro_Unknown:
+               return new_Unknown(config.lowered_mode);
+       default:
+               panic("didn't expect %+F to have mode_b", node);
+       }
 }
 
 static void lower_mode_b_walker(ir_node *node, void *env)
 {
        int i, arity;
+       int changed = 0;
        (void) env;
 
        arity = get_irn_arity(node);
@@ -270,9 +362,9 @@ static void lower_mode_b_walker(ir_node *node, void *env)
                if(get_irn_mode(in) != mode_b)
                        continue;
 
-               if(! lower_direct_cmp) {
-                       if(is_Cond(node)
-                                       || (is_Psi(node) && get_irn_mode(node) != mode_b)) {
+               if(! config.lower_direct_cmp) {
+                       if (is_Cond(node) ||
+                           (is_Mux(node) && get_irn_mode(node) != mode_b)) {
                                if(is_Proj(in)) {
                                        ir_node *pred = get_Proj_pred(in);
                                        if(is_Cmp(pred))
@@ -282,8 +374,22 @@ static void lower_mode_b_walker(ir_node *node, void *env)
                }
 
                lowered_in = lower_node(in);
-               lowered_in = create_convb(lowered_in);
+
+               if(is_Return(node)) {
+                       ir_entity *entity = get_irg_entity(current_ir_graph);
+                       ir_type   *type   = get_entity_type(entity);
+                       adjust_method_type(type);
+               } else if(is_Call(node)) {
+                       ir_type *type = get_Call_type(node);
+                       adjust_method_type(type);
+               } else {
+                       lowered_in = create_convb(lowered_in);
+               }
                set_irn_n(node, i, lowered_in);
+               changed = 1;
+       }
+       if(changed) {
+               add_identities(current_ir_graph->value_table, node);
        }
 }
 
@@ -293,12 +399,21 @@ static void clear_links(ir_node *node, void *env)
        set_irn_link(node, NULL);
 }
 
-void ir_lower_mode_b(ir_graph *irg, ir_mode *mode, int do_lower_direct_cmp)
+void ir_lower_mode_b(ir_graph *irg, const lower_mode_b_config_t *nconfig)
 {
-       lowered_mode     = mode;
-       lower_direct_cmp = do_lower_direct_cmp;
-       set_using_irn_link(irg);
+       config        = *nconfig;
+       lowered_nodes = new_pdeq();
+
+       ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK);
+
        irg_walk_graph(irg, clear_links, NULL, NULL);
        irg_walk_graph(irg, lower_mode_b_walker, NULL, NULL);
-       clear_using_irn_link(irg);
+
+       while(!pdeq_empty(lowered_nodes)) {
+               ir_node *node = (ir_node*) pdeq_getr(lowered_nodes);
+               maybe_kill_node(node);
+       }
+       del_pdeq(lowered_nodes);
+
+       ir_free_resources(irg, IR_RESOURCE_IRN_LINK);
 }