1 /*
2  * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
3  *
4  * This file is part of libFirm.
5  *
6  * This file may be distributed and/or modified under the terms of the
7  * GNU General Public License version 2 as published by the Free Software
8  * Foundation and appearing in the file LICENSE.GPL included in the
9  * packaging of this file.
10  *
11  * Licensees holding valid libFirm Professional Edition licenses may use
12  * this file in accordance with the libFirm Commercial License.
13  * Agreement provided with the Software.
14  *
15  * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16  * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
17  * PURPOSE.
18  */
19 
20 /**
21  * @file
22  * @brief       A data structure to treat nodes and node-proj collections uniformly.
23  * @author      Sebastian Hack
24  */
25 #include "config.h"
26 
27 #include "irgraph_t.h"
28 #include "irmode_t.h"
29 #include "irnode_t.h"
30 #include "iredges.h"
31 
32 #include "besched.h"
33 #include "beinsn_t.h"
34 #include "beirg.h"
35 #include "beabi.h"
36 #include "raw_bitset.h"
37 
38 /**
39  * Create a be_insn_t for an IR node.
40  *
41  * @param env      the insn construction environment
42  * @param irn      the irn for which the be_insn should be build
43  *
44  * @return the be_insn for the IR node
45  */
be_scan_insn(const be_insn_env_t * env,ir_node * irn)46 be_insn_t *be_scan_insn(const be_insn_env_t *env, ir_node *irn)
47 {
48 	struct obstack *obst = env->obst;
49 	be_operand_t o;
50 	int i, n;
51 	int pre_colored = 0;
52 
53 	be_insn_t *insn = OALLOCZ(obst, be_insn_t);
54 
55 	insn->irn       = irn;
56 	insn->next_insn = sched_next(irn);
57 	if (get_irn_mode(irn) == mode_T) {
58 		ir_node *p;
59 
60 		/* This instruction might create more than one def. These are handled
61 		   by Proj's, find them. */
62 		foreach_out_edge(irn, edge) {
63 			p = get_edge_src_irn(edge);
64 
65 			/* did not work if the result is a ProjT. This should NOT happen
66 			   in the backend, but check it for now. */
67 			assert(get_irn_mode(p) != mode_T);
68 
69 			if (arch_irn_consider_in_reg_alloc(env->cls, p)) {
70 				/* found a def: create a new operand */
71 				o.req             = arch_get_irn_register_req(p);
72 				o.carrier         = p;
73 				o.irn             = irn;
74 				o.pos             = -(get_Proj_proj(p) + 1);
75 				o.partner         = NULL;
76 				o.has_constraints = arch_register_req_is(o.req, limited) | (o.req->width > 1);
77 				obstack_grow(obst, &o, sizeof(o));
78 				insn->n_ops++;
79 				insn->out_constraints |= o.has_constraints;
80 				pre_colored += arch_get_irn_register(p) != NULL;
81 			}
82 		}
83 	} else if (arch_irn_consider_in_reg_alloc(env->cls, irn)) {
84 		/* only one def, create one operand */
85 		o.req     = arch_get_irn_register_req(irn);
86 		o.carrier = irn;
87 		o.irn     = irn;
88 		o.pos     = -1;
89 		o.partner = NULL;
90 		o.has_constraints = arch_register_req_is(o.req, limited) | (o.req->width > 1);
91 		obstack_grow(obst, &o, sizeof(o));
92 		insn->n_ops++;
93 		insn->out_constraints |= o.has_constraints;
94 		pre_colored += arch_get_irn_register(irn) != NULL;
95 	}
96 
97 	if (pre_colored > 0) {
98 		assert(pre_colored == insn->n_ops && "partly pre-colored nodes not supported");
99 		insn->pre_colored = 1;
100 	}
101 	insn->use_start   = insn->n_ops;
102 
103 	/* now collect the uses for this node */
104 	for (i = 0, n = get_irn_arity(irn); i < n; ++i) {
105 		ir_node *op = get_irn_n(irn, i);
106 
107 		if (arch_irn_consider_in_reg_alloc(env->cls, op)) {
108 			/* found a register use, create an operand */
109 			o.req     = arch_get_irn_register_req_in(irn, i);
110 			o.carrier = op;
111 			o.irn     = irn;
112 			o.pos     = i;
113 			o.partner = NULL;
114 			o.has_constraints = arch_register_req_is(o.req, limited);
115 			obstack_grow(obst, &o, sizeof(o));
116 			insn->n_ops++;
117 			insn->in_constraints |= o.has_constraints;
118 		}
119 	}
120 
121 	insn->has_constraints = insn->in_constraints | insn->out_constraints;
122 	insn->ops = (be_operand_t*)obstack_finish(obst);
123 
124 	/* Compute the admissible registers bitsets. */
125 	for (i = 0; i < insn->n_ops; ++i) {
126 		be_operand_t *op = &insn->ops[i];
127 		const arch_register_req_t   *req = op->req;
128 		const arch_register_class_t *cls = req->cls;
129 		arch_register_req_type_t    type = req->type;
130 
131 		/* If there is no special requirement, we allow current class here */
132 		if (cls == NULL && req->type == arch_register_req_type_none) {
133 			cls  = env->cls;
134 			type = arch_register_req_type_normal;
135 		}
136 
137 		assert(cls == env->cls);
138 
139 		if (type & arch_register_req_type_limited) {
140 			bitset_t *regs = bitset_obstack_alloc(obst, env->cls->n_regs);
141 			rbitset_copy_to_bitset(req->limited, regs);
142 			op->regs = regs;
143 		} else {
144 			op->regs = env->allocatable_regs;
145 		}
146 	}
147 
148 	return insn;
149 }
150