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         ir_node *irn;
  54
  55         mark_Block_block_visited(block);
  56
  57         /* process schedule */
  58         sched_foreach(block, irn) {
  59                 int irn_bias;
  60
  61                 /* set bias to nodes with entities */
  62                 ir_entity *entity = arch_get_frame_entity(irn);
  63                 if (entity != NULL) {
  64                         int offset = get_entity_offset(entity);
  65                         if (sp_relative)
  66                                 offset += bias + SPARC_MIN_STACKSIZE;
  67                         arch_set_frame_offset(irn, offset);
  68                 }
  69
  70                 irn_bias = arch_get_sp_bias(irn);
  71                 if (irn_bias == 0) {
  72                         /* do nothing */
  73                 } else if (irn_bias == SP_BIAS_RESET) {
  74                         bias = 0;
  75                 } else {
  76                         /* adjust values to respect stack alignment */
  77                         int new_bias_unaligned;
  78                         int new_bias_aligned;
  79                         irn_bias -= free_bytes;
  80
  81                         new_bias_unaligned = bias + irn_bias;
  82                         new_bias_aligned
  83                                 = round_up2(new_bias_unaligned, SPARC_STACK_ALIGNMENT);
  84                         free_bytes = new_bias_aligned - new_bias_unaligned;
  85                         set_irn_sp_bias(irn, new_bias_aligned - bias);
  86                         bias = new_bias_aligned;
  87                 }
  88         }
  89
  90 #ifndef NDEBUG
  91         if (block == get_irg_end_block(get_irn_irg(block))) {
  92                 assert(bias == 0);
  93         }
  94 #endif
  95
  96         /* continue at the successor blocks */
  97         foreach_block_succ(block, edge) {
  98                 ir_node *succ = get_edge_src_irn(edge);
  99                 if (Block_block_visited(succ))
 100                         continue;
 101                 process_bias(succ, sp_relative, bias, free_bytes);
 102         }
 103 }
 104
 105 static void adjust_entity_offsets(ir_type *type, long offset)
 106 {
 107         size_t n_members = get_compound_n_members(type);
 108         size_t i;
 109
 110         for (i = 0; i < n_members; ++i) {
 111                 ir_entity *member        = get_compound_member(type, i);
 112                 int        member_offset = get_entity_offset(member);
 113                 set_entity_offset(member, member_offset + offset);
 114         }
 115 }
 116
 117 /**
 118  * Perform some fixups for variadic functions.
 119  * To make the rest of the frontend code easier to understand we add
 120  * "dummy" parameters until the number of parameters transmitted in registers.
 121  * (because otherwise the backend wouldn't store the value of the register
 122  *  parameters into memory for the VLA magic)
 123  */
 124 bool sparc_variadic_fixups(ir_graph *irg, calling_convention_t *cconv)
 125 {
 126         ir_entity *entity = get_irg_entity(irg);
 127         ir_type   *mtp    = get_entity_type(entity);
 128         if (get_method_variadicity(mtp) != variadicity_variadic)
 129                 return false;
 130
 131         if (cconv->n_param_regs >= SPARC_N_PARAM_REGS)
 132                 return false;
 133
 134         {
 135         size_t         n_params     = get_method_n_params(mtp);
 136         type_dbg_info *dbgi         = get_type_dbg_info(mtp);
 137         size_t         n_ress       = get_method_n_ress(mtp);
 138         size_t         new_n_params
 139                 = n_params + (SPARC_N_PARAM_REGS - cconv->n_param_regs);
 140         ir_type       *new_mtp      = new_d_type_method(new_n_params, n_ress, dbgi);
 141         ir_mode       *gp_reg_mode  = sparc_reg_classes[CLASS_sparc_gp].mode;
 142         ir_type       *gp_reg_type  = get_type_for_mode(gp_reg_mode);
 143         ir_type       *frame_type   = get_irg_frame_type(irg);
 144         size_t         i;
 145
 146         for (i = 0; i < n_ress; ++i) {
 147                 ir_type *type = get_method_res_type(mtp, i);
 148                 set_method_res_type(new_mtp, i, type);
 149         }
 150         for (i = 0; i < n_params; ++i) {
 151                 ir_type *type = get_method_param_type(mtp, i);
 152                 set_method_param_type(new_mtp, i, type);
 153         }
 154         for ( ; i < new_n_params; ++i) {
 155                 set_method_param_type(new_mtp, i, gp_reg_type);
 156                 new_parameter_entity(frame_type, i, gp_reg_type);
 157         }
 158
 159         set_method_variadicity(new_mtp, get_method_variadicity(mtp));
 160         set_method_calling_convention(new_mtp, get_method_calling_convention(mtp));
 161         set_method_additional_properties(new_mtp, get_method_additional_properties(mtp));
 162         set_higher_type(new_mtp, mtp);
 163
 164         set_entity_type(entity, new_mtp);
 165         }
 166         return true;
 167 }
 168
 169 static ir_type *compute_arg_type(ir_graph *irg, calling_convention_t *cconv,
 170                                  ir_type *between_type)
 171 {
 172         ir_entity       *va_start_entity = NULL;
 173         const ir_entity *entity          = get_irg_entity(irg);
 174         const ir_type   *mtp             = get_entity_type(entity);
 175         size_t           n_params        = get_method_n_params(mtp);
 176         ir_entity      **param_map       = ALLOCANZ(ir_entity*, n_params);
 177
 178         ir_type *frame_type      = get_irg_frame_type(irg);
 179         size_t   n_frame_members = get_compound_n_members(frame_type);
 180         size_t   f;
 181         size_t   i;
 182
 183         ir_type *res = new_type_struct(id_mangle_u(get_entity_ident(entity), new_id_from_chars("arg_type", 8)));
 184
 185         /* search for existing value_param entities */
 186         for (f = n_frame_members; f > 0; ) {
 187                 ir_entity *member = get_compound_member(frame_type, --f);
 188                 size_t     num;
 189
 190                 if (!is_parameter_entity(member))
 191                         continue;
 192                 num = get_entity_parameter_number(member);
 193                 if (num == IR_VA_START_PARAMETER_NUMBER) {
 194                         if (va_start_entity != NULL)
 195                                 panic("multiple va_start entities found (%+F,%+F)",
 196                                       va_start_entity, member);
 197                         va_start_entity = member;
 198                         continue;
 199                 }
 200                 assert(num < n_params);
 201                 if (param_map[num] != NULL)
 202                         panic("multiple entities for parameter %u in %+F found", f, irg);
 203
 204                 param_map[num] = member;
 205                 /* move to new arg_type */
 206                 set_entity_owner(member, res);
 207         }
 208
 209         /* calculate offsets/create missing entities */
 210         for (i = 0; i < n_params; ++i) {
 211                 reg_or_stackslot_t *param  = &cconv->parameters[i];
 212                 ir_entity          *entity = param_map[i];
 213
 214                 if (param->reg0 != NULL) {
 215                         /* use reserved spill space on between type */
 216                         if (entity != NULL) {
 217                                 long offset = SPARC_PARAMS_SPILL_OFFSET + i * SPARC_REGISTER_SIZE;
 218                                 assert(i < SPARC_N_PARAM_REGS);
 219                                 set_entity_owner(entity, between_type);
 220                                 set_entity_offset(entity, offset);
 221                         }
 222                         continue;
 223                 }
 224
 225                 if (entity == NULL)
 226                         entity = new_parameter_entity(res, i, param->type);
 227                 param->entity = entity;
 228                 set_entity_offset(entity, param->offset);
 229         }
 230
 231         if (va_start_entity != NULL) {
 232                 /* sparc_variadic_fixups() fiddled with our type, find out the
 233                  * original number of parameters */
 234                 ir_type *non_lowered   = get_higher_type(mtp);
 235                 size_t   orig_n_params = get_method_n_params(non_lowered);
 236                 long     offset;
 237                 assert(get_method_variadicity(mtp) == variadicity_variadic);
 238                 if (orig_n_params < n_params) {
 239                         assert(param_map[orig_n_params] != NULL);
 240                         offset = get_entity_offset(param_map[orig_n_params]);
 241                         set_entity_owner(va_start_entity, between_type);
 242                         set_entity_offset(va_start_entity, offset);
 243                 } else {
 244                         set_entity_owner(va_start_entity, res);
 245                         set_entity_offset(va_start_entity, cconv->param_stack_size);
 246                 }
 247         }
 248         set_type_size_bytes(res, cconv->param_stack_size);
 249
 250         return res;
 251 }
 252
 253 void sparc_create_stacklayout(ir_graph *irg, calling_convention_t *cconv)
 254 {
 255         be_stack_layout_t *layout = be_get_irg_stack_layout(irg);
 256         ir_type           *between_type;
 257         memset(layout, 0, sizeof(*layout));
 258
 259         between_type = new_type_class(new_id_from_str("sparc_between_type"));
 260         if (cconv->omit_fp) {
 261                 set_type_size_bytes(between_type, 0);
 262         } else {
 263                 set_type_size_bytes(between_type, SPARC_MIN_STACKSIZE);
 264         }
 265
 266         layout->frame_type     = get_irg_frame_type(irg);
 267         layout->between_type   = between_type;
 268         layout->arg_type       = compute_arg_type(irg, cconv, between_type);
 269         layout->initial_offset = 0;
 270         layout->initial_bias   = 0;
 271         layout->sp_relative    = cconv->omit_fp;
 272
 273         assert(N_FRAME_TYPES == 3);
 274         layout->order[0] = layout->frame_type;
 275         layout->order[1] = layout->between_type;
 276         layout->order[2] = layout->arg_type;
 277 }
 278
 279 /* Assign entity offsets, to all stack-related entities.
 280  * The offsets are relative to the begin of the stack frame.
 281  */
 282 void sparc_adjust_stack_entity_offsets(ir_graph *irg)
 283 {
 284         be_stack_layout_t *layout = be_get_irg_stack_layout(irg);
 285
 286         /* initially the stackpointer points to the begin of our stackframe.
 287          * Situation at the begin of our function:
 288          *
 289          *      high address |-----------------------------|
 290          *                   |            ...              |
 291          *          arg-type |         stackarg 1          |
 292          *                   |         stackarg 0          |
 293          *                   |-----------------------------|
 294          *                   | space for storing regarg0-5 |
 295          *      between type | pointer to aggregate return |
 296          *                   |      16 words save are      |
 297          *  stack pointer -> |-----------------------------|
 298          *                   |    high end of stackframe   |
 299          *                   |            ...              |
 300          *                   |    low end of stackframe    |
 301          *      low address  |-----------------------------|
 302          */
 303         ir_type *between_type = layout->between_type;
 304         unsigned between_size = get_type_size_bytes(between_type);
 305
 306         ir_type *frame_type  = get_irg_frame_type(irg);
 307         unsigned frame_size  = get_type_size_bytes(frame_type);
 308         unsigned frame_align = get_type_alignment_bytes(frame_type);
 309
 310         /* There's the tricky case of the stackframe size not being a multiple
 311          * of the alignment. There are 2 variants:
 312          *
 313          * - frame-pointer relative addressing:
 314          *   Increase frame_size in case it is not a multiple of the alignment as we
 315          *   address entities from the "top" with negative offsets
 316          * - stack-pointer relative addressing:
 317          *   Stackframesize + SPARC_MIN_STACK_SIZE has to be aligned. Increase
 318          *   frame_size accordingly.
 319          */
 320         if (!layout->sp_relative) {
 321                 frame_size = (frame_size + frame_align-1) & ~(frame_align-1);
 322         } else {
 323                 unsigned misalign = (SPARC_MIN_STACKSIZE+frame_size) % frame_align;
 324                 frame_size += misalign;
 325         }
 326         set_type_size_bytes(frame_type, frame_size);
 327
 328         ir_type *arg_type = layout->arg_type;
 329
 330         adjust_entity_offsets(frame_type, -(long)frame_size);
 331         /* no need to adjust between type, it's already at 0 */
 332         adjust_entity_offsets(arg_type, between_size);
 333 }
 334
 335 void sparc_fix_stack_bias(ir_graph *irg)
 336 {
 337         bool sp_relative = be_get_irg_stack_layout(irg)->sp_relative;
 338
 339         ir_node *start_block = get_irg_start_block(irg);
 340
 341         ir_reserve_resources(irg, IR_RESOURCE_BLOCK_VISITED);
 342         inc_irg_block_visited(irg);
 343         process_bias(start_block, sp_relative, 0, 0);
 344         ir_free_resources(irg, IR_RESOURCE_BLOCK_VISITED);
 345 }