nsz Git - libfirm/blob - ir/be/arm/arm_cconv.c

   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   calling convention helpers
  23  * @author  Matthias Braun
  24  * @version $Id$
  25  */
  26 #include "config.h"
  27
  28 #include "arm_cconv.h"
  29 #include "irmode.h"
  30 #include "typerep.h"
  31 #include "xmalloc.h"
  32 #include "error.h"
  33
  34 calling_convention_t *arm_decide_calling_convention(ir_type *function_type)
  35 {
  36         int                   stack_offset = 0;
  37         reg_or_stackslot_t   *params;
  38         reg_or_stackslot_t   *results;
  39         int                   n_param_regs
  40                 = sizeof(param_regs)/sizeof(param_regs[0]);
  41         int                   n_result_regs
  42                 = sizeof(result_regs)/sizeof(result_regs[0]);
  43         int                   n_float_result_regs
  44                 = sizeof(float_result_regs)/sizeof(float_result_regs[0]);
  45         int                   n_params;
  46         int                   n_results;
  47         int                   i;
  48         int                   regnum;
  49         int                   float_regnum;
  50         calling_convention_t *cconv;
  51
  52         /* determine how parameters are passed */
  53         n_params = get_method_n_params(function_type);
  54         regnum   = 0;
  55         params   = XMALLOCNZ(reg_or_stackslot_t, n_params);
  56
  57         for (i = 0; i < n_params; ++i) {
  58                 ir_type            *param_type = get_method_param_type(function_type,i);
  59                 ir_mode            *mode       = get_type_mode(param_type);
  60                 int                 bits       = get_mode_size_bits(mode);
  61                 reg_or_stackslot_t *param      = &params[i];
  62                 param->type = param_type;
  63
  64                 if (regnum < n_param_regs) {
  65                         const arch_register_t *reg = param_regs[regnum++];
  66                         param->reg0 = reg;
  67                 } else {
  68                         param->offset = stack_offset;
  69                         /* increase offset 4 bytes so everything is aligned */
  70                         stack_offset += bits > 32 ? bits/8 : 4;
  71                         continue;
  72                 }
  73
  74                 /* we might need a 2nd 32bit component (for 64bit or double values) */
  75                 if (bits > 32) {
  76                         if (bits > 64)
  77                                 panic("only 32 and 64bit modes supported in arm backend");
  78
  79                         if (regnum < n_param_regs) {
  80                                 const arch_register_t *reg = param_regs[regnum++];
  81                                 param->reg1 = reg;
  82                         } else {
  83                                 ir_mode *mode = param_regs[0]->reg_class->mode;
  84                                 ir_type *type = get_type_for_mode(mode);
  85                                 param->type   = type;
  86                                 param->offset = stack_offset;
  87                                 assert(get_mode_size_bits(mode) == 32);
  88                                 stack_offset += 4;
  89                         }
  90                 }
  91         }
  92
  93         n_results    = get_method_n_ress(function_type);
  94         regnum       = 0;
  95         float_regnum = 0;
  96         results      = XMALLOCNZ(reg_or_stackslot_t, n_results);
  97         for (i = 0; i < n_results; ++i) {
  98                 ir_type            *result_type = get_method_res_type(function_type, i);
  99                 ir_mode            *result_mode = get_type_mode(result_type);
 100                 reg_or_stackslot_t *result      = &results[i];
 101
 102                 if (mode_is_float(result_mode)) {
 103                         if (float_regnum >= n_float_result_regs) {
 104                                 panic("Too many float results for arm backend");
 105                         } else {
 106                                 const arch_register_t *reg = float_result_regs[float_regnum++];
 107                                 result->reg0 = reg;
 108                         }
 109                 } else {
 110                         if (get_mode_size_bits(result_mode) > 32) {
 111                                 panic("Results with more than 32bits not supported by arm backend yet");
 112                         }
 113
 114                         if (regnum >= n_result_regs) {
 115                                 panic("Too many results for arm backend");
 116                         } else {
 117                                 const arch_register_t *reg = result_regs[regnum++];
 118                                 result->reg0 = reg;
 119                         }
 120                 }
 121         }
 122
 123         cconv                   = XMALLOCZ(calling_convention_t);
 124         cconv->parameters       = params;
 125         cconv->param_stack_size = stack_offset;
 126         cconv->results          = results;
 127
 128         return cconv;
 129 }
 130
 131 void arm_free_calling_convention(calling_convention_t *cconv)
 132 {
 133         free(cconv->parameters);
 134         free(cconv->results);
 135         free(cconv);
 136 }