1 | /* Subroutines for manipulating rtx's in semantically interesting ways. |
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2 | Copyright (C) 1987, 1991, 1994, 1995 Free Software Foundation, Inc. |
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3 | |
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4 | This file is part of GNU CC. |
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5 | |
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6 | GNU CC is free software; you can redistribute it and/or modify |
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7 | it under the terms of the GNU General Public License as published by |
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8 | the Free Software Foundation; either version 2, or (at your option) |
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9 | any later version. |
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10 | |
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11 | GNU CC is distributed in the hope that it will be useful, |
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12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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14 | GNU General Public License for more details. |
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15 | |
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16 | You should have received a copy of the GNU General Public License |
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17 | along with GNU CC; see the file COPYING. If not, write to |
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18 | the Free Software Foundation, 59 Temple Place - Suite 330, |
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19 | Boston, MA 02111-1307, USA. */ |
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20 | |
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21 | |
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22 | #include "config.h" |
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23 | #include "rtl.h" |
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24 | #include "tree.h" |
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25 | #include "flags.h" |
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26 | #include "expr.h" |
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27 | #include "hard-reg-set.h" |
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28 | #include "insn-config.h" |
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29 | #include "recog.h" |
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30 | #include "insn-flags.h" |
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31 | #include "insn-codes.h" |
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32 | |
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33 | static rtx break_out_memory_refs PROTO((rtx)); |
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34 | |
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35 | /* Return an rtx for the sum of X and the integer C. |
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36 | |
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37 | This function should be used via the `plus_constant' macro. */ |
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38 | |
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39 | rtx |
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40 | plus_constant_wide (x, c) |
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41 | register rtx x; |
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42 | register HOST_WIDE_INT c; |
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43 | { |
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44 | register RTX_CODE code; |
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45 | register enum machine_mode mode; |
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46 | register rtx tem; |
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47 | int all_constant = 0; |
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48 | |
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49 | if (c == 0) |
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50 | return x; |
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51 | |
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52 | restart: |
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53 | |
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54 | code = GET_CODE (x); |
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55 | mode = GET_MODE (x); |
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56 | switch (code) |
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57 | { |
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58 | case CONST_INT: |
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59 | return GEN_INT (INTVAL (x) + c); |
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60 | |
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61 | case CONST_DOUBLE: |
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62 | { |
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63 | HOST_WIDE_INT l1 = CONST_DOUBLE_LOW (x); |
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64 | HOST_WIDE_INT h1 = CONST_DOUBLE_HIGH (x); |
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65 | HOST_WIDE_INT l2 = c; |
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66 | HOST_WIDE_INT h2 = c < 0 ? ~0 : 0; |
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67 | HOST_WIDE_INT lv, hv; |
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68 | |
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69 | add_double (l1, h1, l2, h2, &lv, &hv); |
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70 | |
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71 | return immed_double_const (lv, hv, VOIDmode); |
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72 | } |
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73 | |
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74 | case MEM: |
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75 | /* If this is a reference to the constant pool, try replacing it with |
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76 | a reference to a new constant. If the resulting address isn't |
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77 | valid, don't return it because we have no way to validize it. */ |
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78 | if (GET_CODE (XEXP (x, 0)) == SYMBOL_REF |
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79 | && CONSTANT_POOL_ADDRESS_P (XEXP (x, 0))) |
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80 | { |
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81 | tem |
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82 | = force_const_mem (GET_MODE (x), |
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83 | plus_constant (get_pool_constant (XEXP (x, 0)), |
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84 | c)); |
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85 | if (memory_address_p (GET_MODE (tem), XEXP (tem, 0))) |
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86 | return tem; |
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87 | } |
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88 | break; |
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89 | |
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90 | case CONST: |
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91 | /* If adding to something entirely constant, set a flag |
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92 | so that we can add a CONST around the result. */ |
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93 | x = XEXP (x, 0); |
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94 | all_constant = 1; |
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95 | goto restart; |
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96 | |
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97 | case SYMBOL_REF: |
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98 | case LABEL_REF: |
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99 | all_constant = 1; |
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100 | break; |
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101 | |
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102 | case PLUS: |
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103 | /* The interesting case is adding the integer to a sum. |
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104 | Look for constant term in the sum and combine |
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105 | with C. For an integer constant term, we make a combined |
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106 | integer. For a constant term that is not an explicit integer, |
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107 | we cannot really combine, but group them together anyway. |
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108 | |
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109 | Use a recursive call in case the remaining operand is something |
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110 | that we handle specially, such as a SYMBOL_REF. */ |
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111 | |
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112 | if (GET_CODE (XEXP (x, 1)) == CONST_INT) |
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113 | return plus_constant (XEXP (x, 0), c + INTVAL (XEXP (x, 1))); |
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114 | else if (CONSTANT_P (XEXP (x, 0))) |
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115 | return gen_rtx (PLUS, mode, |
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116 | plus_constant (XEXP (x, 0), c), |
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117 | XEXP (x, 1)); |
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118 | else if (CONSTANT_P (XEXP (x, 1))) |
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119 | return gen_rtx (PLUS, mode, |
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120 | XEXP (x, 0), |
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121 | plus_constant (XEXP (x, 1), c)); |
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122 | } |
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123 | |
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124 | if (c != 0) |
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125 | x = gen_rtx (PLUS, mode, x, GEN_INT (c)); |
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126 | |
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127 | if (GET_CODE (x) == SYMBOL_REF || GET_CODE (x) == LABEL_REF) |
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128 | return x; |
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129 | else if (all_constant) |
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130 | return gen_rtx (CONST, mode, x); |
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131 | else |
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132 | return x; |
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133 | } |
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134 | |
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135 | /* This is the same as `plus_constant', except that it handles LO_SUM. |
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136 | |
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137 | This function should be used via the `plus_constant_for_output' macro. */ |
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138 | |
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139 | rtx |
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140 | plus_constant_for_output_wide (x, c) |
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141 | register rtx x; |
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142 | register HOST_WIDE_INT c; |
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143 | { |
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144 | register RTX_CODE code = GET_CODE (x); |
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145 | register enum machine_mode mode = GET_MODE (x); |
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146 | int all_constant = 0; |
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147 | |
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148 | if (GET_CODE (x) == LO_SUM) |
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149 | return gen_rtx (LO_SUM, mode, XEXP (x, 0), |
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150 | plus_constant_for_output (XEXP (x, 1), c)); |
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151 | |
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152 | else |
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153 | return plus_constant (x, c); |
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154 | } |
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155 | |
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156 | /* If X is a sum, return a new sum like X but lacking any constant terms. |
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157 | Add all the removed constant terms into *CONSTPTR. |
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158 | X itself is not altered. The result != X if and only if |
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159 | it is not isomorphic to X. */ |
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160 | |
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161 | rtx |
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162 | eliminate_constant_term (x, constptr) |
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163 | rtx x; |
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164 | rtx *constptr; |
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165 | { |
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166 | register rtx x0, x1; |
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167 | rtx tem; |
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168 | |
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169 | if (GET_CODE (x) != PLUS) |
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170 | return x; |
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171 | |
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172 | /* First handle constants appearing at this level explicitly. */ |
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173 | if (GET_CODE (XEXP (x, 1)) == CONST_INT |
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174 | && 0 != (tem = simplify_binary_operation (PLUS, GET_MODE (x), *constptr, |
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175 | XEXP (x, 1))) |
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176 | && GET_CODE (tem) == CONST_INT) |
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177 | { |
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178 | *constptr = tem; |
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179 | return eliminate_constant_term (XEXP (x, 0), constptr); |
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180 | } |
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181 | |
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182 | tem = const0_rtx; |
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183 | x0 = eliminate_constant_term (XEXP (x, 0), &tem); |
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184 | x1 = eliminate_constant_term (XEXP (x, 1), &tem); |
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185 | if ((x1 != XEXP (x, 1) || x0 != XEXP (x, 0)) |
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186 | && 0 != (tem = simplify_binary_operation (PLUS, GET_MODE (x), |
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187 | *constptr, tem)) |
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188 | && GET_CODE (tem) == CONST_INT) |
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189 | { |
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190 | *constptr = tem; |
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191 | return gen_rtx (PLUS, GET_MODE (x), x0, x1); |
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192 | } |
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193 | |
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194 | return x; |
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195 | } |
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196 | |
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197 | /* Returns the insn that next references REG after INSN, or 0 |
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198 | if REG is clobbered before next referenced or we cannot find |
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199 | an insn that references REG in a straight-line piece of code. */ |
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200 | |
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201 | rtx |
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202 | find_next_ref (reg, insn) |
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203 | rtx reg; |
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204 | rtx insn; |
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205 | { |
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206 | rtx next; |
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207 | |
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208 | for (insn = NEXT_INSN (insn); insn; insn = next) |
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209 | { |
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210 | next = NEXT_INSN (insn); |
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211 | if (GET_CODE (insn) == NOTE) |
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212 | continue; |
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213 | if (GET_CODE (insn) == CODE_LABEL |
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214 | || GET_CODE (insn) == BARRIER) |
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215 | return 0; |
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216 | if (GET_CODE (insn) == INSN |
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217 | || GET_CODE (insn) == JUMP_INSN |
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218 | || GET_CODE (insn) == CALL_INSN) |
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219 | { |
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220 | if (reg_set_p (reg, insn)) |
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221 | return 0; |
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222 | if (reg_mentioned_p (reg, PATTERN (insn))) |
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223 | return insn; |
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224 | if (GET_CODE (insn) == JUMP_INSN) |
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225 | { |
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226 | if (simplejump_p (insn)) |
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227 | next = JUMP_LABEL (insn); |
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228 | else |
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229 | return 0; |
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230 | } |
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231 | if (GET_CODE (insn) == CALL_INSN |
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232 | && REGNO (reg) < FIRST_PSEUDO_REGISTER |
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233 | && call_used_regs[REGNO (reg)]) |
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234 | return 0; |
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235 | } |
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236 | else |
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237 | abort (); |
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238 | } |
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239 | return 0; |
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240 | } |
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241 | |
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242 | /* Return an rtx for the size in bytes of the value of EXP. */ |
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243 | |
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244 | rtx |
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245 | expr_size (exp) |
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246 | tree exp; |
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247 | { |
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248 | tree size = size_in_bytes (TREE_TYPE (exp)); |
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249 | |
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250 | if (TREE_CODE (size) != INTEGER_CST |
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251 | && contains_placeholder_p (size)) |
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252 | size = build (WITH_RECORD_EXPR, sizetype, size, exp); |
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253 | |
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254 | return expand_expr (size, NULL_RTX, TYPE_MODE (sizetype), 0); |
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255 | } |
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256 | |
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257 | /* Return a copy of X in which all memory references |
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258 | and all constants that involve symbol refs |
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259 | have been replaced with new temporary registers. |
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260 | Also emit code to load the memory locations and constants |
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261 | into those registers. |
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262 | |
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263 | If X contains no such constants or memory references, |
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264 | X itself (not a copy) is returned. |
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265 | |
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266 | If a constant is found in the address that is not a legitimate constant |
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267 | in an insn, it is left alone in the hope that it might be valid in the |
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268 | address. |
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269 | |
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270 | X may contain no arithmetic except addition, subtraction and multiplication. |
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271 | Values returned by expand_expr with 1 for sum_ok fit this constraint. */ |
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272 | |
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273 | static rtx |
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274 | break_out_memory_refs (x) |
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275 | register rtx x; |
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276 | { |
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277 | if (GET_CODE (x) == MEM |
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278 | || (CONSTANT_P (x) && CONSTANT_ADDRESS_P (x) |
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279 | && GET_MODE (x) != VOIDmode)) |
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280 | x = force_reg (GET_MODE (x), x); |
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281 | else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS |
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282 | || GET_CODE (x) == MULT) |
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283 | { |
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284 | register rtx op0 = break_out_memory_refs (XEXP (x, 0)); |
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285 | register rtx op1 = break_out_memory_refs (XEXP (x, 1)); |
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286 | |
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287 | if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1)) |
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288 | x = gen_rtx (GET_CODE (x), Pmode, op0, op1); |
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289 | } |
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290 | |
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291 | return x; |
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292 | } |
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293 | |
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294 | #ifdef POINTERS_EXTEND_UNSIGNED |
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295 | |
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296 | /* Given X, a memory address in ptr_mode, convert it to an address |
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297 | in Pmode, or vice versa (TO_MODE says which way). We take advantage of |
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298 | the fact that pointers are not allowed to overflow by commuting arithmetic |
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299 | operations over conversions so that address arithmetic insns can be |
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300 | used. */ |
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301 | |
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302 | rtx |
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303 | convert_memory_address (to_mode, x) |
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304 | enum machine_mode to_mode; |
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305 | rtx x; |
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306 | { |
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307 | rtx temp; |
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308 | |
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309 | switch (GET_CODE (x)) |
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310 | { |
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311 | case CONST_INT: |
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312 | case CONST_DOUBLE: |
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313 | return x; |
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314 | |
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315 | case LABEL_REF: |
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316 | return gen_rtx (LABEL_REF, to_mode, XEXP (x, 0)); |
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317 | |
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318 | case SYMBOL_REF: |
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319 | temp = gen_rtx (SYMBOL_REF, to_mode, XSTR (x, 0)); |
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320 | SYMBOL_REF_FLAG (temp) = SYMBOL_REF_FLAG (x); |
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321 | return temp; |
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322 | |
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323 | case PLUS: |
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324 | case MULT: |
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325 | return gen_rtx (GET_CODE (x), to_mode, |
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326 | convert_memory_address (to_mode, XEXP (x, 0)), |
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327 | convert_memory_address (to_mode, XEXP (x, 1))); |
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328 | |
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329 | case CONST: |
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330 | return gen_rtx (CONST, to_mode, |
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331 | convert_memory_address (to_mode, XEXP (x, 0))); |
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332 | |
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333 | default: |
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334 | return convert_modes (to_mode, |
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335 | to_mode == ptr_mode ? Pmode : ptr_mode, |
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336 | x, POINTERS_EXTEND_UNSIGNED); |
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337 | } |
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338 | } |
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339 | #endif |
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340 | |
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341 | /* Given a memory address or facsimile X, construct a new address, |
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342 | currently equivalent, that is stable: future stores won't change it. |
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343 | |
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344 | X must be composed of constants, register and memory references |
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345 | combined with addition, subtraction and multiplication: |
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346 | in other words, just what you can get from expand_expr if sum_ok is 1. |
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347 | |
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348 | Works by making copies of all regs and memory locations used |
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349 | by X and combining them the same way X does. |
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350 | You could also stabilize the reference to this address |
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351 | by copying the address to a register with copy_to_reg; |
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352 | but then you wouldn't get indexed addressing in the reference. */ |
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353 | |
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354 | rtx |
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355 | copy_all_regs (x) |
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356 | register rtx x; |
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357 | { |
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358 | if (GET_CODE (x) == REG) |
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359 | { |
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360 | if (REGNO (x) != FRAME_POINTER_REGNUM |
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361 | #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM |
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362 | && REGNO (x) != HARD_FRAME_POINTER_REGNUM |
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363 | #endif |
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364 | ) |
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365 | x = copy_to_reg (x); |
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366 | } |
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367 | else if (GET_CODE (x) == MEM) |
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368 | x = copy_to_reg (x); |
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369 | else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS |
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370 | || GET_CODE (x) == MULT) |
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371 | { |
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372 | register rtx op0 = copy_all_regs (XEXP (x, 0)); |
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373 | register rtx op1 = copy_all_regs (XEXP (x, 1)); |
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374 | if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1)) |
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375 | x = gen_rtx (GET_CODE (x), Pmode, op0, op1); |
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376 | } |
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377 | return x; |
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378 | } |
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379 | |
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380 | /* Return something equivalent to X but valid as a memory address |
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381 | for something of mode MODE. When X is not itself valid, this |
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382 | works by copying X or subexpressions of it into registers. */ |
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383 | |
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384 | rtx |
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385 | memory_address (mode, x) |
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386 | enum machine_mode mode; |
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387 | register rtx x; |
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388 | { |
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389 | register rtx oldx = x; |
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390 | |
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391 | #ifdef POINTERS_EXTEND_UNSIGNED |
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392 | if (GET_MODE (x) == ptr_mode) |
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393 | x = convert_memory_address (Pmode, x); |
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394 | #endif |
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395 | |
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396 | /* By passing constant addresses thru registers |
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397 | we get a chance to cse them. */ |
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398 | if (! cse_not_expected && CONSTANT_P (x) && CONSTANT_ADDRESS_P (x)) |
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399 | x = force_reg (Pmode, x); |
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400 | |
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401 | /* Accept a QUEUED that refers to a REG |
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402 | even though that isn't a valid address. |
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403 | On attempting to put this in an insn we will call protect_from_queue |
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404 | which will turn it into a REG, which is valid. */ |
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405 | else if (GET_CODE (x) == QUEUED |
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406 | && GET_CODE (QUEUED_VAR (x)) == REG) |
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407 | ; |
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408 | |
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409 | /* We get better cse by rejecting indirect addressing at this stage. |
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410 | Let the combiner create indirect addresses where appropriate. |
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411 | For now, generate the code so that the subexpressions useful to share |
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412 | are visible. But not if cse won't be done! */ |
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413 | else |
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414 | { |
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415 | if (! cse_not_expected && GET_CODE (x) != REG) |
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416 | x = break_out_memory_refs (x); |
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417 | |
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418 | /* At this point, any valid address is accepted. */ |
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419 | GO_IF_LEGITIMATE_ADDRESS (mode, x, win); |
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420 | |
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421 | /* If it was valid before but breaking out memory refs invalidated it, |
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422 | use it the old way. */ |
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423 | if (memory_address_p (mode, oldx)) |
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424 | goto win2; |
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425 | |
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426 | /* Perform machine-dependent transformations on X |
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427 | in certain cases. This is not necessary since the code |
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428 | below can handle all possible cases, but machine-dependent |
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429 | transformations can make better code. */ |
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430 | LEGITIMIZE_ADDRESS (x, oldx, mode, win); |
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431 | |
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432 | /* PLUS and MULT can appear in special ways |
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433 | as the result of attempts to make an address usable for indexing. |
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434 | Usually they are dealt with by calling force_operand, below. |
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435 | But a sum containing constant terms is special |
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436 | if removing them makes the sum a valid address: |
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437 | then we generate that address in a register |
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438 | and index off of it. We do this because it often makes |
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439 | shorter code, and because the addresses thus generated |
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440 | in registers often become common subexpressions. */ |
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441 | if (GET_CODE (x) == PLUS) |
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442 | { |
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443 | rtx constant_term = const0_rtx; |
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444 | rtx y = eliminate_constant_term (x, &constant_term); |
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445 | if (constant_term == const0_rtx |
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446 | || ! memory_address_p (mode, y)) |
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447 | x = force_operand (x, NULL_RTX); |
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448 | else |
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449 | { |
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450 | y = gen_rtx (PLUS, GET_MODE (x), copy_to_reg (y), constant_term); |
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451 | if (! memory_address_p (mode, y)) |
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452 | x = force_operand (x, NULL_RTX); |
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453 | else |
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454 | x = y; |
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455 | } |
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456 | } |
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457 | |
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458 | else if (GET_CODE (x) == MULT || GET_CODE (x) == MINUS) |
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459 | x = force_operand (x, NULL_RTX); |
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460 | |
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461 | /* If we have a register that's an invalid address, |
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462 | it must be a hard reg of the wrong class. Copy it to a pseudo. */ |
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463 | else if (GET_CODE (x) == REG) |
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464 | x = copy_to_reg (x); |
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465 | |
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466 | /* Last resort: copy the value to a register, since |
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467 | the register is a valid address. */ |
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468 | else |
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469 | x = force_reg (Pmode, x); |
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470 | |
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471 | goto done; |
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472 | |
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473 | win2: |
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474 | x = oldx; |
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475 | win: |
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476 | if (flag_force_addr && ! cse_not_expected && GET_CODE (x) != REG |
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477 | /* Don't copy an addr via a reg if it is one of our stack slots. */ |
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478 | && ! (GET_CODE (x) == PLUS |
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479 | && (XEXP (x, 0) == virtual_stack_vars_rtx |
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480 | || XEXP (x, 0) == virtual_incoming_args_rtx))) |
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481 | { |
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482 | if (general_operand (x, Pmode)) |
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483 | x = force_reg (Pmode, x); |
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484 | else |
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485 | x = force_operand (x, NULL_RTX); |
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486 | } |
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487 | } |
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488 | |
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489 | done: |
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490 | |
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491 | /* If we didn't change the address, we are done. Otherwise, mark |
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492 | a reg as a pointer if we have REG or REG + CONST_INT. */ |
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493 | if (oldx == x) |
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494 | return x; |
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495 | else if (GET_CODE (x) == REG) |
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496 | mark_reg_pointer (x); |
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497 | else if (GET_CODE (x) == PLUS |
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498 | && GET_CODE (XEXP (x, 0)) == REG |
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499 | && GET_CODE (XEXP (x, 1)) == CONST_INT) |
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500 | mark_reg_pointer (XEXP (x, 0)); |
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501 | |
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502 | /* OLDX may have been the address on a temporary. Update the address |
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503 | to indicate that X is now used. */ |
---|
504 | update_temp_slot_address (oldx, x); |
---|
505 | |
---|
506 | return x; |
---|
507 | } |
---|
508 | |
---|
509 | /* Like `memory_address' but pretend `flag_force_addr' is 0. */ |
---|
510 | |
---|
511 | rtx |
---|
512 | memory_address_noforce (mode, x) |
---|
513 | enum machine_mode mode; |
---|
514 | rtx x; |
---|
515 | { |
---|
516 | int ambient_force_addr = flag_force_addr; |
---|
517 | rtx val; |
---|
518 | |
---|
519 | flag_force_addr = 0; |
---|
520 | val = memory_address (mode, x); |
---|
521 | flag_force_addr = ambient_force_addr; |
---|
522 | return val; |
---|
523 | } |
---|
524 | |
---|
525 | /* Convert a mem ref into one with a valid memory address. |
---|
526 | Pass through anything else unchanged. */ |
---|
527 | |
---|
528 | rtx |
---|
529 | validize_mem (ref) |
---|
530 | rtx ref; |
---|
531 | { |
---|
532 | if (GET_CODE (ref) != MEM) |
---|
533 | return ref; |
---|
534 | if (memory_address_p (GET_MODE (ref), XEXP (ref, 0))) |
---|
535 | return ref; |
---|
536 | /* Don't alter REF itself, since that is probably a stack slot. */ |
---|
537 | return change_address (ref, GET_MODE (ref), XEXP (ref, 0)); |
---|
538 | } |
---|
539 | |
---|
540 | /* Return a modified copy of X with its memory address copied |
---|
541 | into a temporary register to protect it from side effects. |
---|
542 | If X is not a MEM, it is returned unchanged (and not copied). |
---|
543 | Perhaps even if it is a MEM, if there is no need to change it. */ |
---|
544 | |
---|
545 | rtx |
---|
546 | stabilize (x) |
---|
547 | rtx x; |
---|
548 | { |
---|
549 | register rtx addr; |
---|
550 | if (GET_CODE (x) != MEM) |
---|
551 | return x; |
---|
552 | addr = XEXP (x, 0); |
---|
553 | if (rtx_unstable_p (addr)) |
---|
554 | { |
---|
555 | rtx temp = copy_all_regs (addr); |
---|
556 | rtx mem; |
---|
557 | if (GET_CODE (temp) != REG) |
---|
558 | temp = copy_to_reg (temp); |
---|
559 | mem = gen_rtx (MEM, GET_MODE (x), temp); |
---|
560 | |
---|
561 | /* Mark returned memref with in_struct if it's in an array or |
---|
562 | structure. Copy const and volatile from original memref. */ |
---|
563 | |
---|
564 | MEM_IN_STRUCT_P (mem) = MEM_IN_STRUCT_P (x) || GET_CODE (addr) == PLUS; |
---|
565 | RTX_UNCHANGING_P (mem) = RTX_UNCHANGING_P (x); |
---|
566 | MEM_VOLATILE_P (mem) = MEM_VOLATILE_P (x); |
---|
567 | return mem; |
---|
568 | } |
---|
569 | return x; |
---|
570 | } |
---|
571 | |
---|
572 | /* Copy the value or contents of X to a new temp reg and return that reg. */ |
---|
573 | |
---|
574 | rtx |
---|
575 | copy_to_reg (x) |
---|
576 | rtx x; |
---|
577 | { |
---|
578 | register rtx temp = gen_reg_rtx (GET_MODE (x)); |
---|
579 | |
---|
580 | /* If not an operand, must be an address with PLUS and MULT so |
---|
581 | do the computation. */ |
---|
582 | if (! general_operand (x, VOIDmode)) |
---|
583 | x = force_operand (x, temp); |
---|
584 | |
---|
585 | if (x != temp) |
---|
586 | emit_move_insn (temp, x); |
---|
587 | |
---|
588 | return temp; |
---|
589 | } |
---|
590 | |
---|
591 | /* Like copy_to_reg but always give the new register mode Pmode |
---|
592 | in case X is a constant. */ |
---|
593 | |
---|
594 | rtx |
---|
595 | copy_addr_to_reg (x) |
---|
596 | rtx x; |
---|
597 | { |
---|
598 | return copy_to_mode_reg (Pmode, x); |
---|
599 | } |
---|
600 | |
---|
601 | /* Like copy_to_reg but always give the new register mode MODE |
---|
602 | in case X is a constant. */ |
---|
603 | |
---|
604 | rtx |
---|
605 | copy_to_mode_reg (mode, x) |
---|
606 | enum machine_mode mode; |
---|
607 | rtx x; |
---|
608 | { |
---|
609 | register rtx temp = gen_reg_rtx (mode); |
---|
610 | |
---|
611 | /* If not an operand, must be an address with PLUS and MULT so |
---|
612 | do the computation. */ |
---|
613 | if (! general_operand (x, VOIDmode)) |
---|
614 | x = force_operand (x, temp); |
---|
615 | |
---|
616 | if (GET_MODE (x) != mode && GET_MODE (x) != VOIDmode) |
---|
617 | abort (); |
---|
618 | if (x != temp) |
---|
619 | emit_move_insn (temp, x); |
---|
620 | return temp; |
---|
621 | } |
---|
622 | |
---|
623 | /* Load X into a register if it is not already one. |
---|
624 | Use mode MODE for the register. |
---|
625 | X should be valid for mode MODE, but it may be a constant which |
---|
626 | is valid for all integer modes; that's why caller must specify MODE. |
---|
627 | |
---|
628 | The caller must not alter the value in the register we return, |
---|
629 | since we mark it as a "constant" register. */ |
---|
630 | |
---|
631 | rtx |
---|
632 | force_reg (mode, x) |
---|
633 | enum machine_mode mode; |
---|
634 | rtx x; |
---|
635 | { |
---|
636 | register rtx temp, insn, set; |
---|
637 | |
---|
638 | if (GET_CODE (x) == REG) |
---|
639 | return x; |
---|
640 | temp = gen_reg_rtx (mode); |
---|
641 | insn = emit_move_insn (temp, x); |
---|
642 | |
---|
643 | /* Let optimizers know that TEMP's value never changes |
---|
644 | and that X can be substituted for it. Don't get confused |
---|
645 | if INSN set something else (such as a SUBREG of TEMP). */ |
---|
646 | if (CONSTANT_P (x) |
---|
647 | && (set = single_set (insn)) != 0 |
---|
648 | && SET_DEST (set) == temp) |
---|
649 | { |
---|
650 | rtx note = find_reg_note (insn, REG_EQUAL, NULL_RTX); |
---|
651 | |
---|
652 | if (note) |
---|
653 | XEXP (note, 0) = x; |
---|
654 | else |
---|
655 | REG_NOTES (insn) = gen_rtx (EXPR_LIST, REG_EQUAL, x, REG_NOTES (insn)); |
---|
656 | } |
---|
657 | return temp; |
---|
658 | } |
---|
659 | |
---|
660 | /* If X is a memory ref, copy its contents to a new temp reg and return |
---|
661 | that reg. Otherwise, return X. */ |
---|
662 | |
---|
663 | rtx |
---|
664 | force_not_mem (x) |
---|
665 | rtx x; |
---|
666 | { |
---|
667 | register rtx temp; |
---|
668 | if (GET_CODE (x) != MEM || GET_MODE (x) == BLKmode) |
---|
669 | return x; |
---|
670 | temp = gen_reg_rtx (GET_MODE (x)); |
---|
671 | emit_move_insn (temp, x); |
---|
672 | return temp; |
---|
673 | } |
---|
674 | |
---|
675 | /* Copy X to TARGET (if it's nonzero and a reg) |
---|
676 | or to a new temp reg and return that reg. |
---|
677 | MODE is the mode to use for X in case it is a constant. */ |
---|
678 | |
---|
679 | rtx |
---|
680 | copy_to_suggested_reg (x, target, mode) |
---|
681 | rtx x, target; |
---|
682 | enum machine_mode mode; |
---|
683 | { |
---|
684 | register rtx temp; |
---|
685 | |
---|
686 | if (target && GET_CODE (target) == REG) |
---|
687 | temp = target; |
---|
688 | else |
---|
689 | temp = gen_reg_rtx (mode); |
---|
690 | |
---|
691 | emit_move_insn (temp, x); |
---|
692 | return temp; |
---|
693 | } |
---|
694 | |
---|
695 | /* Return the mode to use to store a scalar of TYPE and MODE. |
---|
696 | PUNSIGNEDP points to the signedness of the type and may be adjusted |
---|
697 | to show what signedness to use on extension operations. |
---|
698 | |
---|
699 | FOR_CALL is non-zero if this call is promoting args for a call. */ |
---|
700 | |
---|
701 | enum machine_mode |
---|
702 | promote_mode (type, mode, punsignedp, for_call) |
---|
703 | tree type; |
---|
704 | enum machine_mode mode; |
---|
705 | int *punsignedp; |
---|
706 | int for_call; |
---|
707 | { |
---|
708 | enum tree_code code = TREE_CODE (type); |
---|
709 | int unsignedp = *punsignedp; |
---|
710 | |
---|
711 | #ifdef PROMOTE_FOR_CALL_ONLY |
---|
712 | if (! for_call) |
---|
713 | return mode; |
---|
714 | #endif |
---|
715 | |
---|
716 | switch (code) |
---|
717 | { |
---|
718 | #ifdef PROMOTE_MODE |
---|
719 | case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE: |
---|
720 | case CHAR_TYPE: case REAL_TYPE: case OFFSET_TYPE: |
---|
721 | PROMOTE_MODE (mode, unsignedp, type); |
---|
722 | break; |
---|
723 | #endif |
---|
724 | |
---|
725 | #ifdef POINTERS_EXTEND_UNSIGNED |
---|
726 | case POINTER_TYPE: |
---|
727 | mode = Pmode; |
---|
728 | unsignedp = POINTERS_EXTEND_UNSIGNED; |
---|
729 | break; |
---|
730 | #endif |
---|
731 | } |
---|
732 | |
---|
733 | *punsignedp = unsignedp; |
---|
734 | return mode; |
---|
735 | } |
---|
736 | |
---|
737 | /* Adjust the stack pointer by ADJUST (an rtx for a number of bytes). |
---|
738 | This pops when ADJUST is positive. ADJUST need not be constant. */ |
---|
739 | |
---|
740 | void |
---|
741 | adjust_stack (adjust) |
---|
742 | rtx adjust; |
---|
743 | { |
---|
744 | rtx temp; |
---|
745 | adjust = protect_from_queue (adjust, 0); |
---|
746 | |
---|
747 | if (adjust == const0_rtx) |
---|
748 | return; |
---|
749 | |
---|
750 | temp = expand_binop (Pmode, |
---|
751 | #ifdef STACK_GROWS_DOWNWARD |
---|
752 | add_optab, |
---|
753 | #else |
---|
754 | sub_optab, |
---|
755 | #endif |
---|
756 | stack_pointer_rtx, adjust, stack_pointer_rtx, 0, |
---|
757 | OPTAB_LIB_WIDEN); |
---|
758 | |
---|
759 | if (temp != stack_pointer_rtx) |
---|
760 | emit_move_insn (stack_pointer_rtx, temp); |
---|
761 | } |
---|
762 | |
---|
763 | /* Adjust the stack pointer by minus ADJUST (an rtx for a number of bytes). |
---|
764 | This pushes when ADJUST is positive. ADJUST need not be constant. */ |
---|
765 | |
---|
766 | void |
---|
767 | anti_adjust_stack (adjust) |
---|
768 | rtx adjust; |
---|
769 | { |
---|
770 | rtx temp; |
---|
771 | adjust = protect_from_queue (adjust, 0); |
---|
772 | |
---|
773 | if (adjust == const0_rtx) |
---|
774 | return; |
---|
775 | |
---|
776 | temp = expand_binop (Pmode, |
---|
777 | #ifdef STACK_GROWS_DOWNWARD |
---|
778 | sub_optab, |
---|
779 | #else |
---|
780 | add_optab, |
---|
781 | #endif |
---|
782 | stack_pointer_rtx, adjust, stack_pointer_rtx, 0, |
---|
783 | OPTAB_LIB_WIDEN); |
---|
784 | |
---|
785 | if (temp != stack_pointer_rtx) |
---|
786 | emit_move_insn (stack_pointer_rtx, temp); |
---|
787 | } |
---|
788 | |
---|
789 | /* Round the size of a block to be pushed up to the boundary required |
---|
790 | by this machine. SIZE is the desired size, which need not be constant. */ |
---|
791 | |
---|
792 | rtx |
---|
793 | round_push (size) |
---|
794 | rtx size; |
---|
795 | { |
---|
796 | #ifdef STACK_BOUNDARY |
---|
797 | int align = STACK_BOUNDARY / BITS_PER_UNIT; |
---|
798 | if (align == 1) |
---|
799 | return size; |
---|
800 | if (GET_CODE (size) == CONST_INT) |
---|
801 | { |
---|
802 | int new = (INTVAL (size) + align - 1) / align * align; |
---|
803 | if (INTVAL (size) != new) |
---|
804 | size = GEN_INT (new); |
---|
805 | } |
---|
806 | else |
---|
807 | { |
---|
808 | /* CEIL_DIV_EXPR needs to worry about the addition overflowing, |
---|
809 | but we know it can't. So add ourselves and then do TRUNC_DIV_EXPR. */ |
---|
810 | size = expand_binop (Pmode, add_optab, size, GEN_INT (align - 1), |
---|
811 | NULL_RTX, 1, OPTAB_LIB_WIDEN); |
---|
812 | size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size, GEN_INT (align), |
---|
813 | NULL_RTX, 1); |
---|
814 | size = expand_mult (Pmode, size, GEN_INT (align), NULL_RTX, 1); |
---|
815 | } |
---|
816 | #endif /* STACK_BOUNDARY */ |
---|
817 | return size; |
---|
818 | } |
---|
819 | |
---|
820 | /* Save the stack pointer for the purpose in SAVE_LEVEL. PSAVE is a pointer |
---|
821 | to a previously-created save area. If no save area has been allocated, |
---|
822 | this function will allocate one. If a save area is specified, it |
---|
823 | must be of the proper mode. |
---|
824 | |
---|
825 | The insns are emitted after insn AFTER, if nonzero, otherwise the insns |
---|
826 | are emitted at the current position. */ |
---|
827 | |
---|
828 | void |
---|
829 | emit_stack_save (save_level, psave, after) |
---|
830 | enum save_level save_level; |
---|
831 | rtx *psave; |
---|
832 | rtx after; |
---|
833 | { |
---|
834 | rtx sa = *psave; |
---|
835 | /* The default is that we use a move insn and save in a Pmode object. */ |
---|
836 | rtx (*fcn) () = gen_move_insn; |
---|
837 | enum machine_mode mode = Pmode; |
---|
838 | |
---|
839 | /* See if this machine has anything special to do for this kind of save. */ |
---|
840 | switch (save_level) |
---|
841 | { |
---|
842 | #ifdef HAVE_save_stack_block |
---|
843 | case SAVE_BLOCK: |
---|
844 | if (HAVE_save_stack_block) |
---|
845 | { |
---|
846 | fcn = gen_save_stack_block; |
---|
847 | mode = insn_operand_mode[CODE_FOR_save_stack_block][0]; |
---|
848 | } |
---|
849 | break; |
---|
850 | #endif |
---|
851 | #ifdef HAVE_save_stack_function |
---|
852 | case SAVE_FUNCTION: |
---|
853 | if (HAVE_save_stack_function) |
---|
854 | { |
---|
855 | fcn = gen_save_stack_function; |
---|
856 | mode = insn_operand_mode[CODE_FOR_save_stack_function][0]; |
---|
857 | } |
---|
858 | break; |
---|
859 | #endif |
---|
860 | #ifdef HAVE_save_stack_nonlocal |
---|
861 | case SAVE_NONLOCAL: |
---|
862 | if (HAVE_save_stack_nonlocal) |
---|
863 | { |
---|
864 | fcn = gen_save_stack_nonlocal; |
---|
865 | mode = insn_operand_mode[(int) CODE_FOR_save_stack_nonlocal][0]; |
---|
866 | } |
---|
867 | break; |
---|
868 | #endif |
---|
869 | } |
---|
870 | |
---|
871 | /* If there is no save area and we have to allocate one, do so. Otherwise |
---|
872 | verify the save area is the proper mode. */ |
---|
873 | |
---|
874 | if (sa == 0) |
---|
875 | { |
---|
876 | if (mode != VOIDmode) |
---|
877 | { |
---|
878 | if (save_level == SAVE_NONLOCAL) |
---|
879 | *psave = sa = assign_stack_local (mode, GET_MODE_SIZE (mode), 0); |
---|
880 | else |
---|
881 | *psave = sa = gen_reg_rtx (mode); |
---|
882 | } |
---|
883 | } |
---|
884 | else |
---|
885 | { |
---|
886 | if (mode == VOIDmode || GET_MODE (sa) != mode) |
---|
887 | abort (); |
---|
888 | } |
---|
889 | |
---|
890 | if (after) |
---|
891 | { |
---|
892 | rtx seq; |
---|
893 | |
---|
894 | start_sequence (); |
---|
895 | /* We must validize inside the sequence, to ensure that any instructions |
---|
896 | created by the validize call also get moved to the right place. */ |
---|
897 | if (sa != 0) |
---|
898 | sa = validize_mem (sa); |
---|
899 | emit_insn (fcn (sa, stack_pointer_rtx)); |
---|
900 | seq = gen_sequence (); |
---|
901 | end_sequence (); |
---|
902 | emit_insn_after (seq, after); |
---|
903 | } |
---|
904 | else |
---|
905 | { |
---|
906 | if (sa != 0) |
---|
907 | sa = validize_mem (sa); |
---|
908 | emit_insn (fcn (sa, stack_pointer_rtx)); |
---|
909 | } |
---|
910 | } |
---|
911 | |
---|
912 | /* Restore the stack pointer for the purpose in SAVE_LEVEL. SA is the save |
---|
913 | area made by emit_stack_save. If it is zero, we have nothing to do. |
---|
914 | |
---|
915 | Put any emitted insns after insn AFTER, if nonzero, otherwise at |
---|
916 | current position. */ |
---|
917 | |
---|
918 | void |
---|
919 | emit_stack_restore (save_level, sa, after) |
---|
920 | enum save_level save_level; |
---|
921 | rtx after; |
---|
922 | rtx sa; |
---|
923 | { |
---|
924 | /* The default is that we use a move insn. */ |
---|
925 | rtx (*fcn) () = gen_move_insn; |
---|
926 | |
---|
927 | /* See if this machine has anything special to do for this kind of save. */ |
---|
928 | switch (save_level) |
---|
929 | { |
---|
930 | #ifdef HAVE_restore_stack_block |
---|
931 | case SAVE_BLOCK: |
---|
932 | if (HAVE_restore_stack_block) |
---|
933 | fcn = gen_restore_stack_block; |
---|
934 | break; |
---|
935 | #endif |
---|
936 | #ifdef HAVE_restore_stack_function |
---|
937 | case SAVE_FUNCTION: |
---|
938 | if (HAVE_restore_stack_function) |
---|
939 | fcn = gen_restore_stack_function; |
---|
940 | break; |
---|
941 | #endif |
---|
942 | #ifdef HAVE_restore_stack_nonlocal |
---|
943 | |
---|
944 | case SAVE_NONLOCAL: |
---|
945 | if (HAVE_restore_stack_nonlocal) |
---|
946 | fcn = gen_restore_stack_nonlocal; |
---|
947 | break; |
---|
948 | #endif |
---|
949 | } |
---|
950 | |
---|
951 | if (sa != 0) |
---|
952 | sa = validize_mem (sa); |
---|
953 | |
---|
954 | if (after) |
---|
955 | { |
---|
956 | rtx seq; |
---|
957 | |
---|
958 | start_sequence (); |
---|
959 | emit_insn (fcn (stack_pointer_rtx, sa)); |
---|
960 | seq = gen_sequence (); |
---|
961 | end_sequence (); |
---|
962 | emit_insn_after (seq, after); |
---|
963 | } |
---|
964 | else |
---|
965 | emit_insn (fcn (stack_pointer_rtx, sa)); |
---|
966 | } |
---|
967 | |
---|
968 | /* Return an rtx representing the address of an area of memory dynamically |
---|
969 | pushed on the stack. This region of memory is always aligned to |
---|
970 | a multiple of BIGGEST_ALIGNMENT. |
---|
971 | |
---|
972 | Any required stack pointer alignment is preserved. |
---|
973 | |
---|
974 | SIZE is an rtx representing the size of the area. |
---|
975 | TARGET is a place in which the address can be placed. |
---|
976 | |
---|
977 | KNOWN_ALIGN is the alignment (in bits) that we know SIZE has. */ |
---|
978 | |
---|
979 | rtx |
---|
980 | allocate_dynamic_stack_space (size, target, known_align) |
---|
981 | rtx size; |
---|
982 | rtx target; |
---|
983 | int known_align; |
---|
984 | { |
---|
985 | /* If we're asking for zero bytes, it doesn't matter what we point |
---|
986 | to since we can't dereference it. But return a reasonable |
---|
987 | address anyway. */ |
---|
988 | if (size == const0_rtx) |
---|
989 | return virtual_stack_dynamic_rtx; |
---|
990 | |
---|
991 | /* Otherwise, show we're calling alloca or equivalent. */ |
---|
992 | current_function_calls_alloca = 1; |
---|
993 | |
---|
994 | /* Ensure the size is in the proper mode. */ |
---|
995 | if (GET_MODE (size) != VOIDmode && GET_MODE (size) != Pmode) |
---|
996 | size = convert_to_mode (Pmode, size, 1); |
---|
997 | |
---|
998 | /* We will need to ensure that the address we return is aligned to |
---|
999 | BIGGEST_ALIGNMENT. If STACK_DYNAMIC_OFFSET is defined, we don't |
---|
1000 | always know its final value at this point in the compilation (it |
---|
1001 | might depend on the size of the outgoing parameter lists, for |
---|
1002 | example), so we must align the value to be returned in that case. |
---|
1003 | (Note that STACK_DYNAMIC_OFFSET will have a default non-zero value if |
---|
1004 | STACK_POINTER_OFFSET or ACCUMULATE_OUTGOING_ARGS are defined). |
---|
1005 | We must also do an alignment operation on the returned value if |
---|
1006 | the stack pointer alignment is less strict that BIGGEST_ALIGNMENT. |
---|
1007 | |
---|
1008 | If we have to align, we must leave space in SIZE for the hole |
---|
1009 | that might result from the alignment operation. */ |
---|
1010 | |
---|
1011 | #if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET) || defined (ALLOCATE_OUTGOING_ARGS) || ! defined (STACK_BOUNDARY) |
---|
1012 | #define MUST_ALIGN 1 |
---|
1013 | #else |
---|
1014 | #define MUST_ALIGN (STACK_BOUNDARY < BIGGEST_ALIGNMENT) |
---|
1015 | #endif |
---|
1016 | |
---|
1017 | if (MUST_ALIGN) |
---|
1018 | { |
---|
1019 | if (GET_CODE (size) == CONST_INT) |
---|
1020 | size = GEN_INT (INTVAL (size) |
---|
1021 | + (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1)); |
---|
1022 | else |
---|
1023 | size = expand_binop (Pmode, add_optab, size, |
---|
1024 | GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1), |
---|
1025 | NULL_RTX, 1, OPTAB_LIB_WIDEN); |
---|
1026 | } |
---|
1027 | |
---|
1028 | #ifdef SETJMP_VIA_SAVE_AREA |
---|
1029 | /* If setjmp restores regs from a save area in the stack frame, |
---|
1030 | avoid clobbering the reg save area. Note that the offset of |
---|
1031 | virtual_incoming_args_rtx includes the preallocated stack args space. |
---|
1032 | It would be no problem to clobber that, but it's on the wrong side |
---|
1033 | of the old save area. */ |
---|
1034 | { |
---|
1035 | rtx dynamic_offset |
---|
1036 | = expand_binop (Pmode, sub_optab, virtual_stack_dynamic_rtx, |
---|
1037 | stack_pointer_rtx, NULL_RTX, 1, OPTAB_LIB_WIDEN); |
---|
1038 | size = expand_binop (Pmode, add_optab, size, dynamic_offset, |
---|
1039 | NULL_RTX, 1, OPTAB_LIB_WIDEN); |
---|
1040 | } |
---|
1041 | #endif /* SETJMP_VIA_SAVE_AREA */ |
---|
1042 | |
---|
1043 | /* Round the size to a multiple of the required stack alignment. |
---|
1044 | Since the stack if presumed to be rounded before this allocation, |
---|
1045 | this will maintain the required alignment. |
---|
1046 | |
---|
1047 | If the stack grows downward, we could save an insn by subtracting |
---|
1048 | SIZE from the stack pointer and then aligning the stack pointer. |
---|
1049 | The problem with this is that the stack pointer may be unaligned |
---|
1050 | between the execution of the subtraction and alignment insns and |
---|
1051 | some machines do not allow this. Even on those that do, some |
---|
1052 | signal handlers malfunction if a signal should occur between those |
---|
1053 | insns. Since this is an extremely rare event, we have no reliable |
---|
1054 | way of knowing which systems have this problem. So we avoid even |
---|
1055 | momentarily mis-aligning the stack. */ |
---|
1056 | |
---|
1057 | #ifdef STACK_BOUNDARY |
---|
1058 | /* If we added a variable amount to SIZE, |
---|
1059 | we can no longer assume it is aligned. */ |
---|
1060 | #if !defined (SETJMP_VIA_SAVE_AREA) |
---|
1061 | if (MUST_ALIGN || known_align % STACK_BOUNDARY != 0) |
---|
1062 | #endif |
---|
1063 | size = round_push (size); |
---|
1064 | #endif |
---|
1065 | |
---|
1066 | do_pending_stack_adjust (); |
---|
1067 | |
---|
1068 | /* Don't use a TARGET that isn't a pseudo. */ |
---|
1069 | if (target == 0 || GET_CODE (target) != REG |
---|
1070 | || REGNO (target) < FIRST_PSEUDO_REGISTER) |
---|
1071 | target = gen_reg_rtx (Pmode); |
---|
1072 | |
---|
1073 | mark_reg_pointer (target); |
---|
1074 | |
---|
1075 | #ifndef STACK_GROWS_DOWNWARD |
---|
1076 | emit_move_insn (target, virtual_stack_dynamic_rtx); |
---|
1077 | #endif |
---|
1078 | |
---|
1079 | /* Perform the required allocation from the stack. Some systems do |
---|
1080 | this differently than simply incrementing/decrementing from the |
---|
1081 | stack pointer. */ |
---|
1082 | #ifdef HAVE_allocate_stack |
---|
1083 | if (HAVE_allocate_stack) |
---|
1084 | { |
---|
1085 | enum machine_mode mode |
---|
1086 | = insn_operand_mode[(int) CODE_FOR_allocate_stack][0]; |
---|
1087 | |
---|
1088 | size = convert_modes (mode, ptr_mode, size, 1); |
---|
1089 | |
---|
1090 | if (insn_operand_predicate[(int) CODE_FOR_allocate_stack][0] |
---|
1091 | && ! ((*insn_operand_predicate[(int) CODE_FOR_allocate_stack][0]) |
---|
1092 | (size, mode))) |
---|
1093 | size = copy_to_mode_reg (mode, size); |
---|
1094 | |
---|
1095 | emit_insn (gen_allocate_stack (size)); |
---|
1096 | } |
---|
1097 | else |
---|
1098 | #endif |
---|
1099 | { |
---|
1100 | size = convert_modes (Pmode, ptr_mode, size, 1); |
---|
1101 | anti_adjust_stack (size); |
---|
1102 | } |
---|
1103 | |
---|
1104 | #ifdef STACK_GROWS_DOWNWARD |
---|
1105 | emit_move_insn (target, virtual_stack_dynamic_rtx); |
---|
1106 | #endif |
---|
1107 | |
---|
1108 | if (MUST_ALIGN) |
---|
1109 | { |
---|
1110 | /* CEIL_DIV_EXPR needs to worry about the addition overflowing, |
---|
1111 | but we know it can't. So add ourselves and then do TRUNC_DIV_EXPR. */ |
---|
1112 | target = expand_binop (Pmode, add_optab, target, |
---|
1113 | GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1), |
---|
1114 | NULL_RTX, 1, OPTAB_LIB_WIDEN); |
---|
1115 | target = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, target, |
---|
1116 | GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT), |
---|
1117 | NULL_RTX, 1); |
---|
1118 | target = expand_mult (Pmode, target, |
---|
1119 | GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT), |
---|
1120 | NULL_RTX, 1); |
---|
1121 | } |
---|
1122 | |
---|
1123 | /* Some systems require a particular insn to refer to the stack |
---|
1124 | to make the pages exist. */ |
---|
1125 | #ifdef HAVE_probe |
---|
1126 | if (HAVE_probe) |
---|
1127 | emit_insn (gen_probe ()); |
---|
1128 | #endif |
---|
1129 | |
---|
1130 | /* Record the new stack level for nonlocal gotos. */ |
---|
1131 | if (nonlocal_goto_handler_slot != 0) |
---|
1132 | emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX); |
---|
1133 | |
---|
1134 | return target; |
---|
1135 | } |
---|
1136 | |
---|
1137 | /* Return an rtx representing the register or memory location |
---|
1138 | in which a scalar value of data type VALTYPE |
---|
1139 | was returned by a function call to function FUNC. |
---|
1140 | FUNC is a FUNCTION_DECL node if the precise function is known, |
---|
1141 | otherwise 0. */ |
---|
1142 | |
---|
1143 | rtx |
---|
1144 | hard_function_value (valtype, func) |
---|
1145 | tree valtype; |
---|
1146 | tree func; |
---|
1147 | { |
---|
1148 | rtx val = FUNCTION_VALUE (valtype, func); |
---|
1149 | if (GET_CODE (val) == REG |
---|
1150 | && GET_MODE (val) == BLKmode) |
---|
1151 | { |
---|
1152 | int bytes = int_size_in_bytes (valtype); |
---|
1153 | enum machine_mode tmpmode; |
---|
1154 | for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT); |
---|
1155 | tmpmode != MAX_MACHINE_MODE; |
---|
1156 | tmpmode = GET_MODE_WIDER_MODE (tmpmode)) |
---|
1157 | { |
---|
1158 | /* Have we found a large enough mode? */ |
---|
1159 | if (GET_MODE_SIZE (tmpmode) >= bytes) |
---|
1160 | break; |
---|
1161 | } |
---|
1162 | |
---|
1163 | /* No suitable mode found. */ |
---|
1164 | if (tmpmode == MAX_MACHINE_MODE) |
---|
1165 | abort (); |
---|
1166 | |
---|
1167 | PUT_MODE (val, tmpmode); |
---|
1168 | } |
---|
1169 | return val; |
---|
1170 | } |
---|
1171 | |
---|
1172 | /* Return an rtx representing the register or memory location |
---|
1173 | in which a scalar value of mode MODE was returned by a library call. */ |
---|
1174 | |
---|
1175 | rtx |
---|
1176 | hard_libcall_value (mode) |
---|
1177 | enum machine_mode mode; |
---|
1178 | { |
---|
1179 | return LIBCALL_VALUE (mode); |
---|
1180 | } |
---|
1181 | |
---|
1182 | /* Look up the tree code for a given rtx code |
---|
1183 | to provide the arithmetic operation for REAL_ARITHMETIC. |
---|
1184 | The function returns an int because the caller may not know |
---|
1185 | what `enum tree_code' means. */ |
---|
1186 | |
---|
1187 | int |
---|
1188 | rtx_to_tree_code (code) |
---|
1189 | enum rtx_code code; |
---|
1190 | { |
---|
1191 | enum tree_code tcode; |
---|
1192 | |
---|
1193 | switch (code) |
---|
1194 | { |
---|
1195 | case PLUS: |
---|
1196 | tcode = PLUS_EXPR; |
---|
1197 | break; |
---|
1198 | case MINUS: |
---|
1199 | tcode = MINUS_EXPR; |
---|
1200 | break; |
---|
1201 | case MULT: |
---|
1202 | tcode = MULT_EXPR; |
---|
1203 | break; |
---|
1204 | case DIV: |
---|
1205 | tcode = RDIV_EXPR; |
---|
1206 | break; |
---|
1207 | case SMIN: |
---|
1208 | tcode = MIN_EXPR; |
---|
1209 | break; |
---|
1210 | case SMAX: |
---|
1211 | tcode = MAX_EXPR; |
---|
1212 | break; |
---|
1213 | default: |
---|
1214 | tcode = LAST_AND_UNUSED_TREE_CODE; |
---|
1215 | break; |
---|
1216 | } |
---|
1217 | return ((int) tcode); |
---|
1218 | } |
---|