sparc: support va_start
[libfirm] / ir / be / sparc / sparc_stackframe.c
1 /*
2  * Copyright (C) 1995-2010 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   Manage addressing into the stackframe
23  * @author  Matthias Braun
24  * @version $Id$
25  */
26 #include "config.h"
27
28 #include "firm_types.h"
29 #include "irnode_t.h"
30 #include "bearch_sparc_t.h"
31 #include "sparc_new_nodes.h"
32 #include "sparc_cconv.h"
33 #include "bitfiddle.h"
34 #include "../bearch.h"
35 #include "../benode.h"
36 #include "../besched.h"
37
38 static void set_irn_sp_bias(ir_node *node, int new_bias)
39 {
40         if (be_is_IncSP(node)) {
41                 be_set_IncSP_offset(node, new_bias);
42         } else if (is_sparc_Save(node)) {
43                 sparc_attr_t *attr = get_sparc_attr(node);
44                 attr->immediate_value = -new_bias;
45         } else if (is_sparc_Restore(node)) {
46                 sparc_attr_t *attr = get_sparc_attr(node);
47                 attr->immediate_value = new_bias;
48         }
49 }
50
51 static void process_bias(ir_node *block, bool sp_relative, int bias,
52                          int free_bytes)
53 {
54         const ir_edge_t *edge;
55         ir_node         *irn;
56
57         mark_Block_block_visited(block);
58
59         /* process schedule */
60         sched_foreach(block, irn) {
61                 int irn_bias;
62
63                 /* set bias to nodes with entities */
64                 ir_entity *entity = arch_get_frame_entity(irn);
65                 if (entity != NULL) {
66                         int offset = get_entity_offset(entity);
67                         if (sp_relative)
68                                 offset -= bias;
69                         arch_set_frame_offset(irn, offset);
70                 }
71
72                 irn_bias = arch_get_sp_bias(irn);
73                 if (irn_bias == 0) {
74                         /* do nothing */
75                 } else if (irn_bias == SP_BIAS_RESET) {
76                         bias = 0;
77                 } else {
78                         /* adjust values to respect stack alignment */
79                         int new_bias_unaligned;
80                         int new_bias_aligned;
81                         irn_bias -= free_bytes;
82
83                         new_bias_unaligned = bias + irn_bias;
84                         new_bias_aligned   = round_up2(new_bias_unaligned, 8);
85                         free_bytes = new_bias_aligned - new_bias_unaligned;
86                         set_irn_sp_bias(irn, new_bias_aligned - bias);
87                         bias = new_bias_aligned;
88                 }
89         }
90
91 #ifndef NDEBUG
92         if (block == get_irg_end_block(get_irn_irg(block))) {
93                 assert(bias == 0);
94         }
95 #endif
96
97         /* continue at the successor blocks */
98         foreach_block_succ(block, edge) {
99                 ir_node *succ = get_edge_src_irn(edge);
100                 if (Block_block_visited(succ))
101                         continue;
102                 process_bias(succ, sp_relative, bias, free_bytes);
103         }
104 }
105
106 static void adjust_entity_offsets(ir_type *type, long offset)
107 {
108         size_t n_members = get_compound_n_members(type);
109         size_t i;
110
111         for (i = 0; i < n_members; ++i) {
112                 ir_entity *member        = get_compound_member(type, i);
113                 int        member_offset = get_entity_offset(member);
114                 set_entity_offset(member, member_offset + offset);
115         }
116 }
117
118 bool sparc_variadic_fixups(ir_graph *irg, calling_convention_t *cconv)
119 {
120         ir_entity *entity = get_irg_entity(irg);
121         ir_type   *mtp    = get_entity_type(entity);
122         if (get_method_variadicity(mtp) != variadicity_variadic)
123                 return false;
124
125         if (cconv->n_param_regs >= SPARC_N_PARAM_REGS)
126                 return false;
127
128         {
129         size_t         n_params     = get_method_n_params(mtp);
130         type_dbg_info *dbgi         = get_type_dbg_info(mtp);
131         size_t         n_ress       = get_method_n_ress(mtp);
132         size_t         new_n_params
133                 = n_params + (SPARC_N_PARAM_REGS - cconv->n_param_regs);
134         ir_type       *new_mtp      = new_d_type_method(new_n_params, n_ress, dbgi);
135         ir_mode       *gp_reg_mode  = sparc_reg_classes[CLASS_sparc_gp].mode;
136         ir_type       *gp_reg_type  = get_type_for_mode(gp_reg_mode);
137         ir_type       *frame_type   = get_irg_frame_type(irg);
138         size_t         i;
139
140         for (i = 0; i < n_ress; ++i) {
141                 ir_type *type = get_method_res_type(mtp, i);
142                 set_method_res_type(new_mtp, i, type);
143         }
144         for (i = 0; i < n_params; ++i) {
145                 ir_type *type = get_method_param_type(mtp, i);
146                 set_method_param_type(new_mtp, i, type);
147         }
148         for ( ; i < new_n_params; ++i) {
149                 set_method_param_type(new_mtp, i, gp_reg_type);
150                 new_parameter_entity(frame_type, i, gp_reg_type);
151         }
152
153         set_method_variadicity(new_mtp, get_method_variadicity(mtp));
154         set_method_calling_convention(new_mtp, get_method_calling_convention(mtp));
155         set_method_additional_properties(new_mtp, get_method_additional_properties(mtp));
156         set_lowered_type(mtp, new_mtp);
157
158         set_entity_type(entity, new_mtp);
159         }
160         return true;
161 }
162
163 static ir_type *compute_arg_type(ir_graph *irg, calling_convention_t *cconv,
164                                  ir_type *between_type)
165 {
166         ir_entity       *va_start_entity = NULL;
167         const ir_entity *entity          = get_irg_entity(irg);
168         const ir_type   *mtp             = get_entity_type(entity);
169         size_t           n_params        = get_method_n_params(mtp);
170         ir_entity      **param_map       = ALLOCANZ(ir_entity*, n_params);
171
172         ir_type *frame_type      = get_irg_frame_type(irg);
173         size_t   n_frame_members = get_compound_n_members(frame_type);
174         size_t   f;
175         size_t   i;
176
177         ir_type *res = new_type_struct(id_mangle_u(get_entity_ident(entity), new_id_from_chars("arg_type", 8)));
178
179         /* search for existing value_param entities */
180         for (f = n_frame_members; f > 0; ) {
181                 ir_entity *member = get_compound_member(frame_type, --f);
182                 size_t     num;
183
184                 if (!is_parameter_entity(member))
185                         continue;
186                 num = get_entity_parameter_number(member);
187                 if (num == IR_VA_START_PARAMETER_NUMBER) {
188                         if (va_start_entity != NULL)
189                                 panic("multiple va_start entities found (%+F,%+F)",
190                                       va_start_entity, member);
191                         va_start_entity = member;
192                         continue;
193                 }
194                 assert(num < n_params);
195                 if (param_map[num] != NULL)
196                         panic("multiple entities for parameter %u in %+F found", f, irg);
197
198                 param_map[num] = member;
199                 /* move to new arg_type */
200                 set_entity_owner(member, res);
201         }
202
203         /* calculate offsets/create missing entities */
204         for (i = 0; i < n_params; ++i) {
205                 reg_or_stackslot_t *param  = &cconv->parameters[i];
206                 ir_entity          *entity = param_map[i];
207
208                 if (param->reg0 != NULL) {
209                         /* use reserved spill space on between type */
210                         if (entity != NULL) {
211                                 long offset = SPARC_PARAMS_SPILL_OFFSET + i*4;
212                                 assert(i < SPARC_N_PARAM_REGS);
213                                 set_entity_owner(entity, between_type);
214                                 set_entity_offset(entity, offset);
215                         }
216                         continue;
217                 }
218
219                 if (entity == NULL)
220                         entity = new_parameter_entity(res, i, param->type);
221                 param->entity = entity;
222                 set_entity_offset(entity, param->offset);
223         }
224
225         if (va_start_entity != NULL) {
226                 /* sparc_variadic_fixups() fiddled with our type, find out the
227                  * original number of parameters */
228                 ir_type *non_lowered   = get_associated_type(mtp);
229                 size_t   orig_n_params = get_method_n_params(non_lowered);
230                 long     offset;
231                 assert(get_method_variadicity(mtp) == variadicity_variadic);
232                 if (orig_n_params < n_params) {
233                         assert(param_map[orig_n_params] != NULL);
234                         offset = get_entity_offset(param_map[orig_n_params]);
235                         set_entity_owner(va_start_entity, between_type);
236                         set_entity_offset(va_start_entity, offset);
237                 } else {
238                         set_entity_owner(va_start_entity, res);
239                         set_entity_offset(va_start_entity, cconv->param_stack_size);
240                 }
241         }
242         set_type_size_bytes(res, cconv->param_stack_size);
243
244         return res;
245 }
246
247 void sparc_create_stacklayout(ir_graph *irg, calling_convention_t *cconv)
248 {
249         be_stack_layout_t *layout = be_get_irg_stack_layout(irg);
250         ir_type           *between_type;
251         memset(layout, 0, sizeof(*layout));
252
253         between_type = new_type_class(new_id_from_str("sparc_between_type"));
254         set_type_size_bytes(between_type, SPARC_MIN_STACKSIZE);
255
256         layout->frame_type     = get_irg_frame_type(irg);
257         layout->between_type   = between_type;
258         layout->arg_type       = compute_arg_type(irg, cconv, between_type);
259         layout->initial_offset = 0;
260         layout->initial_bias   = 0;
261         layout->sp_relative    = cconv->omit_fp;
262
263         assert(N_FRAME_TYPES == 3);
264         layout->order[0] = layout->frame_type;
265         layout->order[1] = layout->between_type;
266         layout->order[2] = layout->arg_type;
267 }
268
269 /* Assign entity offsets, to all stack-related entities.
270  * The offsets are relative to the begin of the stack frame.
271  */
272 static void process_frame_types(ir_graph *irg)
273 {
274         be_stack_layout_t *layout = be_get_irg_stack_layout(irg);
275
276         /* initially the stackpointer points to the begin of our stackframe.
277          * Situation at the begin of our function:
278          *
279          *      high address |-----------------------------|
280          *                   |            ...              |
281          *          arg-type |         stackarg 1          |
282          *                   |         stackarg 0          |
283          *                   |-----------------------------|
284          *                   | space for storing regarg0-5 |
285          *      between type | pointer to aggregate return |
286          *                   |      16 words save are      |
287          *  stack pointer -> |-----------------------------|
288          *                   |    high end of stackframe   |
289          *                   |            ...              |
290          *                   |    low end of stackframe    |
291          *      low address  |-----------------------------|
292          */
293         ir_type *between_type = layout->between_type;
294         unsigned between_size = get_type_size_bytes(between_type);
295
296         ir_type *frame_type = get_irg_frame_type(irg);
297         unsigned frame_size = get_type_size_bytes(frame_type);
298
299         ir_type *arg_type = layout->arg_type;
300
301         adjust_entity_offsets(frame_type, -(long)frame_size);
302         /* no need to adjust between type, it's already at 0 */
303         adjust_entity_offsets(arg_type, between_size);
304 }
305
306 void sparc_fix_stack_bias(ir_graph *irg)
307 {
308         ir_node *start_block = get_irg_start_block(irg);
309
310         process_frame_types(irg);
311
312         ir_reserve_resources(irg, IR_RESOURCE_BLOCK_VISITED);
313         inc_irg_block_visited(irg);
314         process_bias(start_block, be_get_irg_stack_layout(irg)->sp_relative, 0, 0);
315         ir_free_resources(irg, IR_RESOURCE_BLOCK_VISITED);
316 }