2 * This file is part of libFirm.
3 * Copyright (C) 2012 University of Karlsruhe.
8 * @brief Manage addressing into the stackframe
9 * @author Matthias Braun
15 #include "firm_types.h"
17 #include "bearch_sparc_t.h"
18 #include "sparc_new_nodes.h"
19 #include "sparc_cconv.h"
20 #include "bitfiddle.h"
25 static void set_irn_sp_bias(ir_node *node, int new_bias)
27 if (be_is_IncSP(node)) {
28 be_set_IncSP_offset(node, new_bias);
29 } else if (is_sparc_Save(node)) {
30 sparc_attr_t *attr = get_sparc_attr(node);
31 attr->immediate_value = -new_bias;
32 } else if (is_sparc_Restore(node)) {
33 sparc_attr_t *attr = get_sparc_attr(node);
34 attr->immediate_value = new_bias;
38 static void process_bias(ir_node *block, bool sp_relative, int bias,
41 mark_Block_block_visited(block);
43 /* process schedule */
44 sched_foreach(block, irn) {
47 /* set bias to nodes with entities */
48 ir_entity *entity = arch_get_frame_entity(irn);
50 int offset = get_entity_offset(entity);
52 offset += bias + SPARC_MIN_STACKSIZE;
53 arch_set_frame_offset(irn, offset);
56 /* The additional alignment bytes cannot be used
57 * anymore after alloca. */
58 if (is_sparc_SubSP(irn)) {
60 } else if (is_sparc_AddSP(irn)) {
61 assert(free_bytes == 0);
64 irn_bias = arch_get_sp_bias(irn);
67 } else if (irn_bias == SP_BIAS_RESET) {
70 /* adjust values to respect stack alignment */
71 int new_bias_unaligned;
73 irn_bias -= free_bytes;
75 new_bias_unaligned = bias + irn_bias;
77 = round_up2(new_bias_unaligned, SPARC_STACK_ALIGNMENT);
78 free_bytes = new_bias_aligned - new_bias_unaligned;
79 set_irn_sp_bias(irn, new_bias_aligned - bias);
80 bias = new_bias_aligned;
85 if (block == get_irg_end_block(get_irn_irg(block))) {
90 /* continue at the successor blocks */
91 foreach_block_succ(block, edge) {
92 ir_node *succ = get_edge_src_irn(edge);
93 if (Block_block_visited(succ))
95 process_bias(succ, sp_relative, bias, free_bytes);
99 static void adjust_entity_offsets(ir_type *type, long offset)
101 size_t n_members = get_compound_n_members(type);
104 for (i = 0; i < n_members; ++i) {
105 ir_entity *member = get_compound_member(type, i);
106 int member_offset = get_entity_offset(member);
107 set_entity_offset(member, member_offset + offset);
112 * Perform some fixups for variadic functions.
113 * To make the rest of the frontend code easier to understand we add
114 * "dummy" parameters until the number of parameters transmitted in registers.
115 * (because otherwise the backend wouldn't store the value of the register
116 * parameters into memory for the VLA magic)
118 bool sparc_variadic_fixups(ir_graph *irg, calling_convention_t *cconv)
120 ir_entity *entity = get_irg_entity(irg);
121 ir_type *mtp = get_entity_type(entity);
122 if (get_method_variadicity(mtp) != variadicity_variadic)
125 if (cconv->n_param_regs >= SPARC_N_PARAM_REGS)
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);
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);
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);
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);
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);
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_higher_type(new_mtp, mtp);
158 set_entity_type(entity, new_mtp);
163 static ir_type *compute_arg_type(ir_graph *irg, calling_convention_t *cconv,
164 ir_type *between_type)
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);
172 ir_type *frame_type = get_irg_frame_type(irg);
173 size_t n_frame_members = get_compound_n_members(frame_type);
177 ir_type *res = new_type_struct(id_mangle_u(get_entity_ident(entity), new_id_from_chars("arg_type", 8)));
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);
184 if (!is_parameter_entity(member))
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;
194 assert(num < n_params);
195 if (param_map[num] != NULL)
196 panic("multiple entities for parameter %u in %+F found", f, irg);
198 param_map[num] = member;
199 /* move to new arg_type */
200 set_entity_owner(member, res);
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];
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 * SPARC_REGISTER_SIZE;
212 assert(i < SPARC_N_PARAM_REGS);
213 set_entity_owner(entity, between_type);
214 set_entity_offset(entity, offset);
220 entity = new_parameter_entity(res, i, param->type);
221 param->entity = entity;
222 set_entity_offset(entity, param->offset);
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_higher_type(mtp);
229 size_t orig_n_params = get_method_n_params(non_lowered);
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);
238 set_entity_owner(va_start_entity, res);
239 set_entity_offset(va_start_entity, cconv->param_stack_size);
242 set_type_size_bytes(res, cconv->param_stack_size);
247 void sparc_create_stacklayout(ir_graph *irg, calling_convention_t *cconv)
249 be_stack_layout_t *layout = be_get_irg_stack_layout(irg);
250 ir_type *between_type;
251 memset(layout, 0, sizeof(*layout));
253 between_type = new_type_class(new_id_from_str("sparc_between_type"));
254 if (cconv->omit_fp) {
255 set_type_size_bytes(between_type, 0);
257 set_type_size_bytes(between_type, SPARC_MIN_STACKSIZE);
260 layout->frame_type = get_irg_frame_type(irg);
261 layout->between_type = between_type;
262 layout->arg_type = compute_arg_type(irg, cconv, between_type);
263 layout->initial_offset = 0;
264 layout->initial_bias = 0;
265 layout->sp_relative = cconv->omit_fp;
267 assert(N_FRAME_TYPES == 3);
268 layout->order[0] = layout->frame_type;
269 layout->order[1] = layout->between_type;
270 layout->order[2] = layout->arg_type;
273 /* Assign entity offsets, to all stack-related entities.
274 * The offsets are relative to the begin of the stack frame.
276 void sparc_adjust_stack_entity_offsets(ir_graph *irg)
278 be_stack_layout_t *layout = be_get_irg_stack_layout(irg);
280 /* initially the stackpointer points to the begin of our stackframe.
281 * Situation at the begin of our function:
283 * high address |-----------------------------|
285 * arg-type | stackarg 1 |
287 * |-----------------------------|
288 * | space for storing regarg0-5 |
289 * between type | pointer to aggregate return |
290 * | 16 words save are |
291 * stack pointer -> |-----------------------------|
292 * | high end of stackframe |
294 * | low end of stackframe |
295 * low address |-----------------------------|
297 ir_type *between_type = layout->between_type;
298 unsigned between_size = get_type_size_bytes(between_type);
300 ir_type *frame_type = get_irg_frame_type(irg);
301 unsigned frame_size = get_type_size_bytes(frame_type);
302 unsigned frame_align = get_type_alignment_bytes(frame_type);
304 /* There's the tricky case of the stackframe size not being a multiple
305 * of the alignment. There are 2 variants:
307 * - frame-pointer relative addressing:
308 * Increase frame_size in case it is not a multiple of the alignment as we
309 * address entities from the "top" with negative offsets
310 * - stack-pointer relative addressing:
311 * Stackframesize + SPARC_MIN_STACK_SIZE has to be aligned. Increase
312 * frame_size accordingly.
314 if (!layout->sp_relative) {
315 frame_size = (frame_size + frame_align-1) & ~(frame_align-1);
317 unsigned misalign = (SPARC_MIN_STACKSIZE+frame_size) % frame_align;
318 frame_size += misalign;
320 set_type_size_bytes(frame_type, frame_size);
322 ir_type *arg_type = layout->arg_type;
324 adjust_entity_offsets(frame_type, -(long)frame_size);
325 /* no need to adjust between type, it's already at 0 */
326 adjust_entity_offsets(arg_type, between_size);
329 void sparc_fix_stack_bias(ir_graph *irg)
331 bool sp_relative = be_get_irg_stack_layout(irg)->sp_relative;
333 ir_node *start_block = get_irg_start_block(irg);
335 ir_reserve_resources(irg, IR_RESOURCE_BLOCK_VISITED);
336 inc_irg_block_visited(irg);
337 process_bias(start_block, sp_relative, 0, 0);
338 ir_free_resources(irg, IR_RESOURCE_BLOCK_VISITED);