nsz Git - libfirm/blob - 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  */
  25 #include "config.h"
  26
  27 #include "firm_types.h"
  28 #include "irnode_t.h"
  29 #include "bearch_sparc_t.h"
  30 #include "sparc_new_nodes.h"
  31 #include "sparc_cconv.h"
  32 #include "bitfiddle.h"
  33 #include "bearch.h"
  34 #include "benode.h"
  35 #include "besched.h"
  36
  37 static void set_irn_sp_bias(ir_node *node, int new_bias)
  38 {
  39         if (be_is_IncSP(node)) {
  40                 be_set_IncSP_offset(node, new_bias);
  41         } else if (is_sparc_Save(node)) {
  42                 sparc_attr_t *attr = get_sparc_attr(node);
  43                 attr->immediate_value = -new_bias;
  44         } else if (is_sparc_Restore(node)) {
  45                 sparc_attr_t *attr = get_sparc_attr(node);
  46                 attr->immediate_value = new_bias;
  47         }
  48 }
  49
  50 static void process_bias(ir_node *block, bool sp_relative, int bias,
  51                          int free_bytes)
  52 {
  53         mark_Block_block_visited(block);
  54
  55         /* process schedule */
  56         sched_foreach(block, irn) {
  57                 int irn_bias;
  58
  59                 /* set bias to nodes with entities */
  60                 ir_entity *entity = arch_get_frame_entity(irn);
  61                 if (entity != NULL) {
  62                         int offset = get_entity_offset(entity);
  63                         if (sp_relative)
  64                                 offset += bias + SPARC_MIN_STACKSIZE;
  65                         arch_set_frame_offset(irn, offset);
  66                 }
  67
  68                 irn_bias = arch_get_sp_bias(irn);
  69                 if (irn_bias == 0) {
  70                         /* do nothing */
  71                 } else if (irn_bias == SP_BIAS_RESET) {
  72                         bias = 0;
  73                 } else {
  74                         /* adjust values to respect stack alignment */
  75                         int new_bias_unaligned;
  76                         int new_bias_aligned;
  77                         irn_bias -= free_bytes;
  78
  79                         new_bias_unaligned = bias + irn_bias;
  80                         new_bias_aligned
  81                                 = round_up2(new_bias_unaligned, SPARC_STACK_ALIGNMENT);
  82                         free_bytes = new_bias_aligned - new_bias_unaligned;
  83                         set_irn_sp_bias(irn, new_bias_aligned - bias);
  84                         bias = new_bias_aligned;
  85                 }
  86         }
  87
  88 #ifndef NDEBUG
  89         if (block == get_irg_end_block(get_irn_irg(block))) {
  90                 assert(bias == 0);
  91         }
  92 #endif
  93
  94         /* continue at the successor blocks */
  95         foreach_block_succ(block, edge) {
  96                 ir_node *succ = get_edge_src_irn(edge);
  97                 if (Block_block_visited(succ))
  98                         continue;
  99                 process_bias(succ, sp_relative, bias, free_bytes);
 100         }
 101 }
 102
 103 static void adjust_entity_offsets(ir_type *type, long offset)
 104 {
 105         size_t n_members = get_compound_n_members(type);
 106         size_t i;
 107
 108         for (i = 0; i < n_members; ++i) {
 109                 ir_entity *member        = get_compound_member(type, i);
 110                 int        member_offset = get_entity_offset(member);
 111                 set_entity_offset(member, member_offset + offset);
 112         }
 113 }
 114
 115 /**
 116  * Perform some fixups for variadic functions.
 117  * To make the rest of the frontend code easier to understand we add
 118  * "dummy" parameters until the number of parameters transmitted in registers.
 119  * (because otherwise the backend wouldn't store the value of the register
 120  *  parameters into memory for the VLA magic)
 121  */
 122 bool sparc_variadic_fixups(ir_graph *irg, calling_convention_t *cconv)
 123 {
 124         ir_entity *entity = get_irg_entity(irg);
 125         ir_type   *mtp    = get_entity_type(entity);
 126         if (get_method_variadicity(mtp) != variadicity_variadic)
 127                 return false;
 128
 129         if (cconv->n_param_regs >= SPARC_N_PARAM_REGS)
 130                 return false;
 131
 132         {
 133         size_t         n_params     = get_method_n_params(mtp);
 134         type_dbg_info *dbgi         = get_type_dbg_info(mtp);
 135         size_t         n_ress       = get_method_n_ress(mtp);
 136         size_t         new_n_params
 137                 = n_params + (SPARC_N_PARAM_REGS - cconv->n_param_regs);
 138         ir_type       *new_mtp      = new_d_type_method(new_n_params, n_ress, dbgi);
 139         ir_mode       *gp_reg_mode  = sparc_reg_classes[CLASS_sparc_gp].mode;
 140         ir_type       *gp_reg_type  = get_type_for_mode(gp_reg_mode);
 141         ir_type       *frame_type   = get_irg_frame_type(irg);
 142         size_t         i;
 143
 144         for (i = 0; i < n_ress; ++i) {
 145                 ir_type *type = get_method_res_type(mtp, i);
 146                 set_method_res_type(new_mtp, i, type);
 147         }
 148         for (i = 0; i < n_params; ++i) {
 149                 ir_type *type = get_method_param_type(mtp, i);
 150                 set_method_param_type(new_mtp, i, type);
 151         }
 152         for ( ; i < new_n_params; ++i) {
 153                 set_method_param_type(new_mtp, i, gp_reg_type);
 154                 new_parameter_entity(frame_type, i, gp_reg_type);
 155         }
 156
 157         set_method_variadicity(new_mtp, get_method_variadicity(mtp));
 158         set_method_calling_convention(new_mtp, get_method_calling_convention(mtp));
 159         set_method_additional_properties(new_mtp, get_method_additional_properties(mtp));
 160         set_higher_type(new_mtp, mtp);
 161
 162         set_entity_type(entity, new_mtp);
 163         }
 164         return true;
 165 }
 166
 167 static ir_type *compute_arg_type(ir_graph *irg, calling_convention_t *cconv,
 168                                  ir_type *between_type)
 169 {
 170         ir_entity       *va_start_entity = NULL;
 171         const ir_entity *entity          = get_irg_entity(irg);
 172         const ir_type   *mtp             = get_entity_type(entity);
 173         size_t           n_params        = get_method_n_params(mtp);
 174         ir_entity      **param_map       = ALLOCANZ(ir_entity*, n_params);
 175
 176         ir_type *frame_type      = get_irg_frame_type(irg);
 177         size_t   n_frame_members = get_compound_n_members(frame_type);
 178         size_t   f;
 179         size_t   i;
 180
 181         ir_type *res = new_type_struct(id_mangle_u(get_entity_ident(entity), new_id_from_chars("arg_type", 8)));
 182
 183         /* search for existing value_param entities */
 184         for (f = n_frame_members; f > 0; ) {
 185                 ir_entity *member = get_compound_member(frame_type, --f);
 186                 size_t     num;
 187
 188                 if (!is_parameter_entity(member))
 189                         continue;
 190                 num = get_entity_parameter_number(member);
 191                 if (num == IR_VA_START_PARAMETER_NUMBER) {
 192                         if (va_start_entity != NULL)
 193                                 panic("multiple va_start entities found (%+F,%+F)",
 194                                       va_start_entity, member);
 195                         va_start_entity = member;
 196                         continue;
 197                 }
 198                 assert(num < n_params);
 199                 if (param_map[num] != NULL)
 200                         panic("multiple entities for parameter %u in %+F found", f, irg);
 201
 202                 param_map[num] = member;
 203                 /* move to new arg_type */
 204                 set_entity_owner(member, res);
 205         }
 206
 207         /* calculate offsets/create missing entities */
 208         for (i = 0; i < n_params; ++i) {
 209                 reg_or_stackslot_t *param  = &cconv->parameters[i];
 210                 ir_entity          *entity = param_map[i];
 211
 212                 if (param->reg0 != NULL) {
 213                         /* use reserved spill space on between type */
 214                         if (entity != NULL) {
 215                                 long offset = SPARC_PARAMS_SPILL_OFFSET + i * SPARC_REGISTER_SIZE;
 216                                 assert(i < SPARC_N_PARAM_REGS);
 217                                 set_entity_owner(entity, between_type);
 218                                 set_entity_offset(entity, offset);
 219                         }
 220                         continue;
 221                 }
 222
 223                 if (entity == NULL)
 224                         entity = new_parameter_entity(res, i, param->type);
 225                 param->entity = entity;
 226                 set_entity_offset(entity, param->offset);
 227         }
 228
 229         if (va_start_entity != NULL) {
 230                 /* sparc_variadic_fixups() fiddled with our type, find out the
 231                  * original number of parameters */
 232                 ir_type *non_lowered   = get_higher_type(mtp);
 233                 size_t   orig_n_params = get_method_n_params(non_lowered);
 234                 long     offset;
 235                 assert(get_method_variadicity(mtp) == variadicity_variadic);
 236                 if (orig_n_params < n_params) {
 237                         assert(param_map[orig_n_params] != NULL);
 238                         offset = get_entity_offset(param_map[orig_n_params]);
 239                         set_entity_owner(va_start_entity, between_type);
 240                         set_entity_offset(va_start_entity, offset);
 241                 } else {
 242                         set_entity_owner(va_start_entity, res);
 243                         set_entity_offset(va_start_entity, cconv->param_stack_size);
 244                 }
 245         }
 246         set_type_size_bytes(res, cconv->param_stack_size);
 247
 248         return res;
 249 }
 250
 251 void sparc_create_stacklayout(ir_graph *irg, calling_convention_t *cconv)
 252 {
 253         be_stack_layout_t *layout = be_get_irg_stack_layout(irg);
 254         ir_type           *between_type;
 255         memset(layout, 0, sizeof(*layout));
 256
 257         between_type = new_type_class(new_id_from_str("sparc_between_type"));
 258         if (cconv->omit_fp) {
 259                 set_type_size_bytes(between_type, 0);
 260         } else {
 261                 set_type_size_bytes(between_type, SPARC_MIN_STACKSIZE);
 262         }
 263
 264         layout->frame_type     = get_irg_frame_type(irg);
 265         layout->between_type   = between_type;
 266         layout->arg_type       = compute_arg_type(irg, cconv, between_type);
 267         layout->initial_offset = 0;
 268         layout->initial_bias   = 0;
 269         layout->sp_relative    = cconv->omit_fp;
 270
 271         assert(N_FRAME_TYPES == 3);
 272         layout->order[0] = layout->frame_type;
 273         layout->order[1] = layout->between_type;
 274         layout->order[2] = layout->arg_type;
 275 }
 276
 277 /* Assign entity offsets, to all stack-related entities.
 278  * The offsets are relative to the begin of the stack frame.
 279  */
 280 void sparc_adjust_stack_entity_offsets(ir_graph *irg)
 281 {
 282         be_stack_layout_t *layout = be_get_irg_stack_layout(irg);
 283
 284         /* initially the stackpointer points to the begin of our stackframe.
 285          * Situation at the begin of our function:
 286          *
 287          *      high address |-----------------------------|
 288          *                   |            ...              |
 289          *          arg-type |         stackarg 1          |
 290          *                   |         stackarg 0          |
 291          *                   |-----------------------------|
 292          *                   | space for storing regarg0-5 |
 293          *      between type | pointer to aggregate return |
 294          *                   |      16 words save are      |
 295          *  stack pointer -> |-----------------------------|
 296          *                   |    high end of stackframe   |
 297          *                   |            ...              |
 298          *                   |    low end of stackframe    |
 299          *      low address  |-----------------------------|
 300          */
 301         ir_type *between_type = layout->between_type;
 302         unsigned between_size = get_type_size_bytes(between_type);
 303
 304         ir_type *frame_type  = get_irg_frame_type(irg);
 305         unsigned frame_size  = get_type_size_bytes(frame_type);
 306         unsigned frame_align = get_type_alignment_bytes(frame_type);
 307
 308         /* There's the tricky case of the stackframe size not being a multiple
 309          * of the alignment. There are 2 variants:
 310          *
 311          * - frame-pointer relative addressing:
 312          *   Increase frame_size in case it is not a multiple of the alignment as we
 313          *   address entities from the "top" with negative offsets
 314          * - stack-pointer relative addressing:
 315          *   Stackframesize + SPARC_MIN_STACK_SIZE has to be aligned. Increase
 316          *   frame_size accordingly.
 317          */
 318         if (!layout->sp_relative) {
 319                 frame_size = (frame_size + frame_align-1) & ~(frame_align-1);
 320         } else {
 321                 unsigned misalign = (SPARC_MIN_STACKSIZE+frame_size) % frame_align;
 322                 frame_size += misalign;
 323         }
 324         set_type_size_bytes(frame_type, frame_size);
 325
 326         ir_type *arg_type = layout->arg_type;
 327
 328         adjust_entity_offsets(frame_type, -(long)frame_size);
 329         /* no need to adjust between type, it's already at 0 */
 330         adjust_entity_offsets(arg_type, between_size);
 331 }
 332
 333 void sparc_fix_stack_bias(ir_graph *irg)
 334 {
 335         bool sp_relative = be_get_irg_stack_layout(irg)->sp_relative;
 336
 337         ir_node *start_block = get_irg_start_block(irg);
 338
 339         ir_reserve_resources(irg, IR_RESOURCE_BLOCK_VISITED);
 340         inc_irg_block_visited(irg);
 341         process_bias(start_block, sp_relative, 0, 0);
 342         ir_free_resources(irg, IR_RESOURCE_BLOCK_VISITED);
 343 }