0
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1 /*
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2 * Copyright 2005 Sun Microsystems, Inc. All Rights Reserved.
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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4 *
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5 * This code is free software; you can redistribute it and/or modify it
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6 * under the terms of the GNU General Public License version 2 only, as
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7 * published by the Free Software Foundation.
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8 *
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9 * This code is distributed in the hope that it will be useful, but WITHOUT
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10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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12 * version 2 for more details (a copy is included in the LICENSE file that
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13 * accompanied this code).
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14 *
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15 * You should have received a copy of the GNU General Public License version
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16 * 2 along with this work; if not, write to the Free Software Foundation,
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17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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18 *
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19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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20 * CA 95054 USA or visit www.sun.com if you need additional information or
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21 * have any questions.
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22 *
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23 */
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24
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25 #include "incls/_precompiled.incl"
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26 #include "incls/_c1_LinearScan_x86.cpp.incl"
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27
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28
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29 //----------------------------------------------------------------------
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30 // Allocation of FPU stack slots (Intel x86 only)
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31 //----------------------------------------------------------------------
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32
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33 void LinearScan::allocate_fpu_stack() {
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34 // First compute which FPU registers are live at the start of each basic block
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35 // (To minimize the amount of work we have to do if we have to merge FPU stacks)
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36 if (ComputeExactFPURegisterUsage) {
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37 Interval* intervals_in_register, *intervals_in_memory;
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38 create_unhandled_lists(&intervals_in_register, &intervals_in_memory, is_in_fpu_register, NULL);
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39
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40 // ignore memory intervals by overwriting intervals_in_memory
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41 // the dummy interval is needed to enforce the walker to walk until the given id:
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42 // without it, the walker stops when the unhandled-list is empty -> live information
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43 // beyond this point would be incorrect.
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44 Interval* dummy_interval = new Interval(any_reg);
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45 dummy_interval->add_range(max_jint - 2, max_jint - 1);
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46 dummy_interval->set_next(Interval::end());
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47 intervals_in_memory = dummy_interval;
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48
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49 IntervalWalker iw(this, intervals_in_register, intervals_in_memory);
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50
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51 const int num_blocks = block_count();
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52 for (int i = 0; i < num_blocks; i++) {
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53 BlockBegin* b = block_at(i);
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54
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55 // register usage is only needed for merging stacks -> compute only
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56 // when more than one predecessor.
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57 // the block must not have any spill moves at the beginning (checked by assertions)
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58 // spill moves would use intervals that are marked as handled and so the usage bit
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59 // would been set incorrectly
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60
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61 // NOTE: the check for number_of_preds > 1 is necessary. A block with only one
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62 // predecessor may have spill moves at the begin of the block.
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63 // If an interval ends at the current instruction id, it is not possible
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64 // to decide if the register is live or not at the block begin -> the
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65 // register information would be incorrect.
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66 if (b->number_of_preds() > 1) {
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67 int id = b->first_lir_instruction_id();
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68 BitMap regs(FrameMap::nof_fpu_regs);
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69 regs.clear();
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70
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71 iw.walk_to(id); // walk after the first instruction (always a label) of the block
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72 assert(iw.current_position() == id, "did not walk completely to id");
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73
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74 // Only consider FPU values in registers
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75 Interval* interval = iw.active_first(fixedKind);
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76 while (interval != Interval::end()) {
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77 int reg = interval->assigned_reg();
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78 assert(reg >= pd_first_fpu_reg && reg <= pd_last_fpu_reg, "no fpu register");
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79 assert(interval->assigned_regHi() == -1, "must not have hi register (doubles stored in one register)");
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80 assert(interval->from() <= id && id < interval->to(), "interval out of range");
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81
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82 #ifndef PRODUCT
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83 if (TraceFPURegisterUsage) {
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84 tty->print("fpu reg %d is live because of ", reg - pd_first_fpu_reg); interval->print();
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85 }
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86 #endif
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87
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88 regs.set_bit(reg - pd_first_fpu_reg);
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89 interval = interval->next();
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90 }
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91
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92 b->set_fpu_register_usage(regs);
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93
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94 #ifndef PRODUCT
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95 if (TraceFPURegisterUsage) {
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96 tty->print("FPU regs for block %d, LIR instr %d): ", b->block_id(), id); regs.print_on(tty); tty->print_cr("");
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97 }
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98 #endif
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99 }
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100 }
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101 }
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102
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103 FpuStackAllocator alloc(ir()->compilation(), this);
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104 _fpu_stack_allocator = &alloc;
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105 alloc.allocate();
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106 _fpu_stack_allocator = NULL;
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107 }
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108
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109
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110 FpuStackAllocator::FpuStackAllocator(Compilation* compilation, LinearScan* allocator)
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111 : _compilation(compilation)
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112 , _lir(NULL)
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113 , _pos(-1)
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114 , _allocator(allocator)
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115 , _sim(compilation)
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116 , _temp_sim(compilation)
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117 {}
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118
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119 void FpuStackAllocator::allocate() {
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120 int num_blocks = allocator()->block_count();
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121 for (int i = 0; i < num_blocks; i++) {
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122 // Set up to process block
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123 BlockBegin* block = allocator()->block_at(i);
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124 intArray* fpu_stack_state = block->fpu_stack_state();
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125
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126 #ifndef PRODUCT
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127 if (TraceFPUStack) {
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128 tty->cr();
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129 tty->print_cr("------- Begin of new Block %d -------", block->block_id());
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130 }
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131 #endif
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132
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133 assert(fpu_stack_state != NULL ||
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134 block->end()->as_Base() != NULL ||
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135 block->is_set(BlockBegin::exception_entry_flag),
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136 "FPU stack state must be present due to linear-scan order for FPU stack allocation");
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137 // note: exception handler entries always start with an empty fpu stack
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138 // because stack merging would be too complicated
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139
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140 if (fpu_stack_state != NULL) {
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141 sim()->read_state(fpu_stack_state);
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142 } else {
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143 sim()->clear();
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144 }
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145
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146 #ifndef PRODUCT
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147 if (TraceFPUStack) {
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148 tty->print("Reading FPU state for block %d:", block->block_id());
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149 sim()->print();
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150 tty->cr();
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151 }
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152 #endif
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153
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154 allocate_block(block);
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155 CHECK_BAILOUT();
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156 }
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157 }
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158
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159 void FpuStackAllocator::allocate_block(BlockBegin* block) {
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160 bool processed_merge = false;
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161 LIR_OpList* insts = block->lir()->instructions_list();
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162 set_lir(block->lir());
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163 set_pos(0);
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164
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165
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166 // Note: insts->length() may change during loop
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167 while (pos() < insts->length()) {
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168 LIR_Op* op = insts->at(pos());
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169 _debug_information_computed = false;
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170
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171 #ifndef PRODUCT
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172 if (TraceFPUStack) {
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173 op->print();
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174 }
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175 check_invalid_lir_op(op);
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176 #endif
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177
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178 LIR_OpBranch* branch = op->as_OpBranch();
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179 LIR_Op1* op1 = op->as_Op1();
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180 LIR_Op2* op2 = op->as_Op2();
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181 LIR_OpCall* opCall = op->as_OpCall();
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182
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183 if (branch != NULL && branch->block() != NULL) {
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184 if (!processed_merge) {
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185 // propagate stack at first branch to a successor
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186 processed_merge = true;
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187 bool required_merge = merge_fpu_stack_with_successors(block);
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188
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189 assert(!required_merge || branch->cond() == lir_cond_always, "splitting of critical edges should prevent FPU stack mismatches at cond branches");
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190 }
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191
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192 } else if (op1 != NULL) {
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193 handle_op1(op1);
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194 } else if (op2 != NULL) {
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195 handle_op2(op2);
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196 } else if (opCall != NULL) {
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197 handle_opCall(opCall);
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198 }
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199
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200 compute_debug_information(op);
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201
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202 set_pos(1 + pos());
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203 }
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204
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205 // Propagate stack when block does not end with branch
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206 if (!processed_merge) {
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207 merge_fpu_stack_with_successors(block);
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208 }
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209 }
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210
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211
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212 void FpuStackAllocator::compute_debug_information(LIR_Op* op) {
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213 if (!_debug_information_computed && op->id() != -1 && allocator()->has_info(op->id())) {
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214 visitor.visit(op);
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215
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216 // exception handling
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217 if (allocator()->compilation()->has_exception_handlers()) {
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218 XHandlers* xhandlers = visitor.all_xhandler();
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219 int n = xhandlers->length();
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220 for (int k = 0; k < n; k++) {
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221 allocate_exception_handler(xhandlers->handler_at(k));
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222 }
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223 } else {
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224 assert(visitor.all_xhandler()->length() == 0, "missed exception handler");
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225 }
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226
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227 // compute debug information
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228 int n = visitor.info_count();
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229 assert(n > 0, "should not visit operation otherwise");
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230
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231 for (int j = 0; j < n; j++) {
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232 CodeEmitInfo* info = visitor.info_at(j);
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233 // Compute debug information
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234 allocator()->compute_debug_info(info, op->id());
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235 }
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236 }
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237 _debug_information_computed = true;
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238 }
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239
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240 void FpuStackAllocator::allocate_exception_handler(XHandler* xhandler) {
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241 if (!sim()->is_empty()) {
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242 LIR_List* old_lir = lir();
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243 int old_pos = pos();
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244 intArray* old_state = sim()->write_state();
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245
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246 #ifndef PRODUCT
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247 if (TraceFPUStack) {
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248 tty->cr();
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249 tty->print_cr("------- begin of exception handler -------");
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250 }
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251 #endif
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252
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253 if (xhandler->entry_code() == NULL) {
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254 // need entry code to clear FPU stack
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255 LIR_List* entry_code = new LIR_List(_compilation);
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256 entry_code->jump(xhandler->entry_block());
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257 xhandler->set_entry_code(entry_code);
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258 }
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259
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260 LIR_OpList* insts = xhandler->entry_code()->instructions_list();
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261 set_lir(xhandler->entry_code());
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262 set_pos(0);
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263
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264 // Note: insts->length() may change during loop
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265 while (pos() < insts->length()) {
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266 LIR_Op* op = insts->at(pos());
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267
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268 #ifndef PRODUCT
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269 if (TraceFPUStack) {
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270 op->print();
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271 }
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272 check_invalid_lir_op(op);
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273 #endif
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274
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275 switch (op->code()) {
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276 case lir_move:
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277 assert(op->as_Op1() != NULL, "must be LIR_Op1");
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278 assert(pos() != insts->length() - 1, "must not be last operation");
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279
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280 handle_op1((LIR_Op1*)op);
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281 break;
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282
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283 case lir_branch:
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284 assert(op->as_OpBranch()->cond() == lir_cond_always, "must be unconditional branch");
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285 assert(pos() == insts->length() - 1, "must be last operation");
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286
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287 // remove all remaining dead registers from FPU stack
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288 clear_fpu_stack(LIR_OprFact::illegalOpr);
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289 break;
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290
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291 default:
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292 // other operations not allowed in exception entry code
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293 ShouldNotReachHere();
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294 }
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295
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296 set_pos(pos() + 1);
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297 }
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298
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299 #ifndef PRODUCT
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300 if (TraceFPUStack) {
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301 tty->cr();
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302 tty->print_cr("------- end of exception handler -------");
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303 }
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304 #endif
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305
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306 set_lir(old_lir);
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307 set_pos(old_pos);
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308 sim()->read_state(old_state);
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309 }
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310 }
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311
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312
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313 int FpuStackAllocator::fpu_num(LIR_Opr opr) {
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314 assert(opr->is_fpu_register() && !opr->is_xmm_register(), "shouldn't call this otherwise");
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315 return opr->is_single_fpu() ? opr->fpu_regnr() : opr->fpu_regnrLo();
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316 }
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317
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318 int FpuStackAllocator::tos_offset(LIR_Opr opr) {
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319 return sim()->offset_from_tos(fpu_num(opr));
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320 }
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321
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322
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323 LIR_Opr FpuStackAllocator::to_fpu_stack(LIR_Opr opr) {
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324 assert(opr->is_fpu_register() && !opr->is_xmm_register(), "shouldn't call this otherwise");
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325
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326 int stack_offset = tos_offset(opr);
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327 if (opr->is_single_fpu()) {
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328 return LIR_OprFact::single_fpu(stack_offset)->make_fpu_stack_offset();
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329 } else {
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330 assert(opr->is_double_fpu(), "shouldn't call this otherwise");
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331 return LIR_OprFact::double_fpu(stack_offset)->make_fpu_stack_offset();
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332 }
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333 }
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334
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335 LIR_Opr FpuStackAllocator::to_fpu_stack_top(LIR_Opr opr, bool dont_check_offset) {
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336 assert(opr->is_fpu_register() && !opr->is_xmm_register(), "shouldn't call this otherwise");
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337 assert(dont_check_offset || tos_offset(opr) == 0, "operand is not on stack top");
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338
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339 int stack_offset = 0;
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340 if (opr->is_single_fpu()) {
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341 return LIR_OprFact::single_fpu(stack_offset)->make_fpu_stack_offset();
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342 } else {
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343 assert(opr->is_double_fpu(), "shouldn't call this otherwise");
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344 return LIR_OprFact::double_fpu(stack_offset)->make_fpu_stack_offset();
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345 }
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346 }
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347
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348
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349
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350 void FpuStackAllocator::insert_op(LIR_Op* op) {
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351 lir()->insert_before(pos(), op);
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352 set_pos(1 + pos());
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353 }
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354
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355
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356 void FpuStackAllocator::insert_exchange(int offset) {
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357 if (offset > 0) {
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358 LIR_Op1* fxch_op = new LIR_Op1(lir_fxch, LIR_OprFact::intConst(offset), LIR_OprFact::illegalOpr);
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359 insert_op(fxch_op);
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360 sim()->swap(offset);
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361
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362 #ifndef PRODUCT
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363 if (TraceFPUStack) {
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364 tty->print("Exchanged register: %d New state: ", sim()->get_slot(0)); sim()->print(); tty->cr();
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365 }
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366 #endif
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367
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368 }
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369 }
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370
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371 void FpuStackAllocator::insert_exchange(LIR_Opr opr) {
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372 insert_exchange(tos_offset(opr));
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373 }
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374
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375
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376 void FpuStackAllocator::insert_free(int offset) {
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377 // move stack slot to the top of stack and then pop it
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378 insert_exchange(offset);
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379
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380 LIR_Op* fpop = new LIR_Op0(lir_fpop_raw);
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381 insert_op(fpop);
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382 sim()->pop();
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383
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384 #ifndef PRODUCT
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385 if (TraceFPUStack) {
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386 tty->print("Inserted pop New state: "); sim()->print(); tty->cr();
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387 }
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388 #endif
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389 }
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390
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391
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392 void FpuStackAllocator::insert_free_if_dead(LIR_Opr opr) {
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393 if (sim()->contains(fpu_num(opr))) {
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394 int res_slot = tos_offset(opr);
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395 insert_free(res_slot);
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396 }
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397 }
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398
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399 void FpuStackAllocator::insert_free_if_dead(LIR_Opr opr, LIR_Opr ignore) {
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400 if (fpu_num(opr) != fpu_num(ignore) && sim()->contains(fpu_num(opr))) {
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401 int res_slot = tos_offset(opr);
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402 insert_free(res_slot);
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403 }
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404 }
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405
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406 void FpuStackAllocator::insert_copy(LIR_Opr from, LIR_Opr to) {
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407 int offset = tos_offset(from);
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408 LIR_Op1* fld = new LIR_Op1(lir_fld, LIR_OprFact::intConst(offset), LIR_OprFact::illegalOpr);
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409 insert_op(fld);
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410
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411 sim()->push(fpu_num(to));
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412
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413 #ifndef PRODUCT
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414 if (TraceFPUStack) {
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415 tty->print("Inserted copy (%d -> %d) New state: ", fpu_num(from), fpu_num(to)); sim()->print(); tty->cr();
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416 }
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417 #endif
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418 }
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419
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420 void FpuStackAllocator::do_rename(LIR_Opr from, LIR_Opr to) {
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421 sim()->rename(fpu_num(from), fpu_num(to));
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422 }
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423
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424 void FpuStackAllocator::do_push(LIR_Opr opr) {
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425 sim()->push(fpu_num(opr));
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426 }
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427
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428 void FpuStackAllocator::pop_if_last_use(LIR_Op* op, LIR_Opr opr) {
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429 assert(op->fpu_pop_count() == 0, "fpu_pop_count alredy set");
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430 assert(tos_offset(opr) == 0, "can only pop stack top");
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431
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432 if (opr->is_last_use()) {
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433 op->set_fpu_pop_count(1);
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434 sim()->pop();
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435 }
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436 }
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437
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438 void FpuStackAllocator::pop_always(LIR_Op* op, LIR_Opr opr) {
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439 assert(op->fpu_pop_count() == 0, "fpu_pop_count alredy set");
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440 assert(tos_offset(opr) == 0, "can only pop stack top");
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441
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442 op->set_fpu_pop_count(1);
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443 sim()->pop();
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444 }
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445
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446 void FpuStackAllocator::clear_fpu_stack(LIR_Opr preserve) {
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447 int result_stack_size = (preserve->is_fpu_register() && !preserve->is_xmm_register() ? 1 : 0);
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448 while (sim()->stack_size() > result_stack_size) {
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449 assert(!sim()->slot_is_empty(0), "not allowed");
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450
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451 if (result_stack_size == 0 || sim()->get_slot(0) != fpu_num(preserve)) {
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452 insert_free(0);
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453 } else {
|
|
454 // move "preserve" to bottom of stack so that all other stack slots can be popped
|
|
455 insert_exchange(sim()->stack_size() - 1);
|
|
456 }
|
|
457 }
|
|
458 }
|
|
459
|
|
460
|
|
461 void FpuStackAllocator::handle_op1(LIR_Op1* op1) {
|
|
462 LIR_Opr in = op1->in_opr();
|
|
463 LIR_Opr res = op1->result_opr();
|
|
464
|
|
465 LIR_Opr new_in = in; // new operands relative to the actual fpu stack top
|
|
466 LIR_Opr new_res = res;
|
|
467
|
|
468 // Note: this switch is processed for all LIR_Op1, regardless if they have FPU-arguments,
|
|
469 // so checks for is_float_kind() are necessary inside the cases
|
|
470 switch (op1->code()) {
|
|
471
|
|
472 case lir_return: {
|
|
473 // FPU-Stack must only contain the (optional) fpu return value.
|
|
474 // All remaining dead values are popped from the stack
|
|
475 // If the input operand is a fpu-register, it is exchanged to the bottom of the stack
|
|
476
|
|
477 clear_fpu_stack(in);
|
|
478 if (in->is_fpu_register() && !in->is_xmm_register()) {
|
|
479 new_in = to_fpu_stack_top(in);
|
|
480 }
|
|
481
|
|
482 break;
|
|
483 }
|
|
484
|
|
485 case lir_move: {
|
|
486 if (in->is_fpu_register() && !in->is_xmm_register()) {
|
|
487 if (res->is_xmm_register()) {
|
|
488 // move from fpu register to xmm register (necessary for operations that
|
|
489 // are not available in the SSE instruction set)
|
|
490 insert_exchange(in);
|
|
491 new_in = to_fpu_stack_top(in);
|
|
492 pop_always(op1, in);
|
|
493
|
|
494 } else if (res->is_fpu_register() && !res->is_xmm_register()) {
|
|
495 // move from fpu-register to fpu-register:
|
|
496 // * input and result register equal:
|
|
497 // nothing to do
|
|
498 // * input register is last use:
|
|
499 // rename the input register to result register -> input register
|
|
500 // not present on fpu-stack afterwards
|
|
501 // * input register not last use:
|
|
502 // duplicate input register to result register to preserve input
|
|
503 //
|
|
504 // Note: The LIR-Assembler does not produce any code for fpu register moves,
|
|
505 // so input and result stack index must be equal
|
|
506
|
|
507 if (fpu_num(in) == fpu_num(res)) {
|
|
508 // nothing to do
|
|
509 } else if (in->is_last_use()) {
|
|
510 insert_free_if_dead(res);//, in);
|
|
511 do_rename(in, res);
|
|
512 } else {
|
|
513 insert_free_if_dead(res);
|
|
514 insert_copy(in, res);
|
|
515 }
|
|
516 new_in = to_fpu_stack(res);
|
|
517 new_res = new_in;
|
|
518
|
|
519 } else {
|
|
520 // move from fpu-register to memory
|
|
521 // input operand must be on top of stack
|
|
522
|
|
523 insert_exchange(in);
|
|
524
|
|
525 // create debug information here because afterwards the register may have been popped
|
|
526 compute_debug_information(op1);
|
|
527
|
|
528 new_in = to_fpu_stack_top(in);
|
|
529 pop_if_last_use(op1, in);
|
|
530 }
|
|
531
|
|
532 } else if (res->is_fpu_register() && !res->is_xmm_register()) {
|
|
533 // move from memory/constant to fpu register
|
|
534 // result is pushed on the stack
|
|
535
|
|
536 insert_free_if_dead(res);
|
|
537
|
|
538 // create debug information before register is pushed
|
|
539 compute_debug_information(op1);
|
|
540
|
|
541 do_push(res);
|
|
542 new_res = to_fpu_stack_top(res);
|
|
543 }
|
|
544 break;
|
|
545 }
|
|
546
|
|
547 case lir_neg: {
|
|
548 if (in->is_fpu_register() && !in->is_xmm_register()) {
|
|
549 assert(res->is_fpu_register() && !res->is_xmm_register(), "must be");
|
|
550 assert(in->is_last_use(), "old value gets destroyed");
|
|
551
|
|
552 insert_free_if_dead(res, in);
|
|
553 insert_exchange(in);
|
|
554 new_in = to_fpu_stack_top(in);
|
|
555
|
|
556 do_rename(in, res);
|
|
557 new_res = to_fpu_stack_top(res);
|
|
558 }
|
|
559 break;
|
|
560 }
|
|
561
|
|
562 case lir_convert: {
|
|
563 Bytecodes::Code bc = op1->as_OpConvert()->bytecode();
|
|
564 switch (bc) {
|
|
565 case Bytecodes::_d2f:
|
|
566 case Bytecodes::_f2d:
|
|
567 assert(res->is_fpu_register(), "must be");
|
|
568 assert(in->is_fpu_register(), "must be");
|
|
569
|
|
570 if (!in->is_xmm_register() && !res->is_xmm_register()) {
|
|
571 // this is quite the same as a move from fpu-register to fpu-register
|
|
572 // Note: input and result operands must have different types
|
|
573 if (fpu_num(in) == fpu_num(res)) {
|
|
574 // nothing to do
|
|
575 new_in = to_fpu_stack(in);
|
|
576 } else if (in->is_last_use()) {
|
|
577 insert_free_if_dead(res);//, in);
|
|
578 new_in = to_fpu_stack(in);
|
|
579 do_rename(in, res);
|
|
580 } else {
|
|
581 insert_free_if_dead(res);
|
|
582 insert_copy(in, res);
|
|
583 new_in = to_fpu_stack_top(in, true);
|
|
584 }
|
|
585 new_res = to_fpu_stack(res);
|
|
586 }
|
|
587
|
|
588 break;
|
|
589
|
|
590 case Bytecodes::_i2f:
|
|
591 case Bytecodes::_l2f:
|
|
592 case Bytecodes::_i2d:
|
|
593 case Bytecodes::_l2d:
|
|
594 assert(res->is_fpu_register(), "must be");
|
|
595 if (!res->is_xmm_register()) {
|
|
596 insert_free_if_dead(res);
|
|
597 do_push(res);
|
|
598 new_res = to_fpu_stack_top(res);
|
|
599 }
|
|
600 break;
|
|
601
|
|
602 case Bytecodes::_f2i:
|
|
603 case Bytecodes::_d2i:
|
|
604 assert(in->is_fpu_register(), "must be");
|
|
605 if (!in->is_xmm_register()) {
|
|
606 insert_exchange(in);
|
|
607 new_in = to_fpu_stack_top(in);
|
|
608
|
|
609 // TODO: update registes of stub
|
|
610 }
|
|
611 break;
|
|
612
|
|
613 case Bytecodes::_f2l:
|
|
614 case Bytecodes::_d2l:
|
|
615 assert(in->is_fpu_register(), "must be");
|
|
616 if (!in->is_xmm_register()) {
|
|
617 insert_exchange(in);
|
|
618 new_in = to_fpu_stack_top(in);
|
|
619 pop_always(op1, in);
|
|
620 }
|
|
621 break;
|
|
622
|
|
623 case Bytecodes::_i2l:
|
|
624 case Bytecodes::_l2i:
|
|
625 case Bytecodes::_i2b:
|
|
626 case Bytecodes::_i2c:
|
|
627 case Bytecodes::_i2s:
|
|
628 // no fpu operands
|
|
629 break;
|
|
630
|
|
631 default:
|
|
632 ShouldNotReachHere();
|
|
633 }
|
|
634 break;
|
|
635 }
|
|
636
|
|
637 case lir_roundfp: {
|
|
638 assert(in->is_fpu_register() && !in->is_xmm_register(), "input must be in register");
|
|
639 assert(res->is_stack(), "result must be on stack");
|
|
640
|
|
641 insert_exchange(in);
|
|
642 new_in = to_fpu_stack_top(in);
|
|
643 pop_if_last_use(op1, in);
|
|
644 break;
|
|
645 }
|
|
646
|
|
647 default: {
|
|
648 assert(!in->is_float_kind() && !res->is_float_kind(), "missed a fpu-operation");
|
|
649 }
|
|
650 }
|
|
651
|
|
652 op1->set_in_opr(new_in);
|
|
653 op1->set_result_opr(new_res);
|
|
654 }
|
|
655
|
|
656 void FpuStackAllocator::handle_op2(LIR_Op2* op2) {
|
|
657 LIR_Opr left = op2->in_opr1();
|
|
658 if (!left->is_float_kind()) {
|
|
659 return;
|
|
660 }
|
|
661 if (left->is_xmm_register()) {
|
|
662 return;
|
|
663 }
|
|
664
|
|
665 LIR_Opr right = op2->in_opr2();
|
|
666 LIR_Opr res = op2->result_opr();
|
|
667 LIR_Opr new_left = left; // new operands relative to the actual fpu stack top
|
|
668 LIR_Opr new_right = right;
|
|
669 LIR_Opr new_res = res;
|
|
670
|
|
671 assert(!left->is_xmm_register() && !right->is_xmm_register() && !res->is_xmm_register(), "not for xmm registers");
|
|
672
|
|
673 switch (op2->code()) {
|
|
674 case lir_cmp:
|
|
675 case lir_cmp_fd2i:
|
|
676 case lir_ucmp_fd2i: {
|
|
677 assert(left->is_fpu_register(), "invalid LIR");
|
|
678 assert(right->is_fpu_register(), "invalid LIR");
|
|
679
|
|
680 // the left-hand side must be on top of stack.
|
|
681 // the right-hand side is never popped, even if is_last_use is set
|
|
682 insert_exchange(left);
|
|
683 new_left = to_fpu_stack_top(left);
|
|
684 new_right = to_fpu_stack(right);
|
|
685 pop_if_last_use(op2, left);
|
|
686 break;
|
|
687 }
|
|
688
|
|
689 case lir_mul_strictfp:
|
|
690 case lir_div_strictfp: {
|
|
691 assert(op2->tmp_opr()->is_fpu_register(), "strict operations need temporary fpu stack slot");
|
|
692 insert_free_if_dead(op2->tmp_opr());
|
|
693 assert(sim()->stack_size() <= 7, "at least one stack slot must be free");
|
|
694 // fall-through: continue with the normal handling of lir_mul and lir_div
|
|
695 }
|
|
696 case lir_add:
|
|
697 case lir_sub:
|
|
698 case lir_mul:
|
|
699 case lir_div: {
|
|
700 assert(left->is_fpu_register(), "must be");
|
|
701 assert(res->is_fpu_register(), "must be");
|
|
702 assert(left->is_equal(res), "must be");
|
|
703
|
|
704 // either the left-hand or the right-hand side must be on top of stack
|
|
705 // (if right is not a register, left must be on top)
|
|
706 if (!right->is_fpu_register()) {
|
|
707 insert_exchange(left);
|
|
708 new_left = to_fpu_stack_top(left);
|
|
709 } else {
|
|
710 // no exchange necessary if right is alredy on top of stack
|
|
711 if (tos_offset(right) == 0) {
|
|
712 new_left = to_fpu_stack(left);
|
|
713 new_right = to_fpu_stack_top(right);
|
|
714 } else {
|
|
715 insert_exchange(left);
|
|
716 new_left = to_fpu_stack_top(left);
|
|
717 new_right = to_fpu_stack(right);
|
|
718 }
|
|
719
|
|
720 if (right->is_last_use()) {
|
|
721 op2->set_fpu_pop_count(1);
|
|
722
|
|
723 if (tos_offset(right) == 0) {
|
|
724 sim()->pop();
|
|
725 } else {
|
|
726 // if left is on top of stack, the result is placed in the stack
|
|
727 // slot of right, so a renaming from right to res is necessary
|
|
728 assert(tos_offset(left) == 0, "must be");
|
|
729 sim()->pop();
|
|
730 do_rename(right, res);
|
|
731 }
|
|
732 }
|
|
733 }
|
|
734 new_res = to_fpu_stack(res);
|
|
735
|
|
736 break;
|
|
737 }
|
|
738
|
|
739 case lir_rem: {
|
|
740 assert(left->is_fpu_register(), "must be");
|
|
741 assert(right->is_fpu_register(), "must be");
|
|
742 assert(res->is_fpu_register(), "must be");
|
|
743 assert(left->is_equal(res), "must be");
|
|
744
|
|
745 // Must bring both operands to top of stack with following operand ordering:
|
|
746 // * fpu stack before rem: ... right left
|
|
747 // * fpu stack after rem: ... left
|
|
748 if (tos_offset(right) != 1) {
|
|
749 insert_exchange(right);
|
|
750 insert_exchange(1);
|
|
751 }
|
|
752 insert_exchange(left);
|
|
753 assert(tos_offset(right) == 1, "check");
|
|
754 assert(tos_offset(left) == 0, "check");
|
|
755
|
|
756 new_left = to_fpu_stack_top(left);
|
|
757 new_right = to_fpu_stack(right);
|
|
758
|
|
759 op2->set_fpu_pop_count(1);
|
|
760 sim()->pop();
|
|
761 do_rename(right, res);
|
|
762
|
|
763 new_res = to_fpu_stack_top(res);
|
|
764 break;
|
|
765 }
|
|
766
|
|
767 case lir_log:
|
|
768 case lir_log10:
|
|
769 case lir_abs:
|
|
770 case lir_sqrt: {
|
|
771 // Right argument appears to be unused
|
|
772 assert(right->is_illegal(), "must be");
|
|
773 assert(left->is_fpu_register(), "must be");
|
|
774 assert(res->is_fpu_register(), "must be");
|
|
775 assert(left->is_last_use(), "old value gets destroyed");
|
|
776
|
|
777 insert_free_if_dead(res, left);
|
|
778 insert_exchange(left);
|
|
779 do_rename(left, res);
|
|
780
|
|
781 new_left = to_fpu_stack_top(res);
|
|
782 new_res = new_left;
|
|
783
|
|
784 op2->set_fpu_stack_size(sim()->stack_size());
|
|
785 break;
|
|
786 }
|
|
787
|
|
788
|
|
789 case lir_tan:
|
|
790 case lir_sin:
|
|
791 case lir_cos: {
|
|
792 // sin and cos need two temporary fpu stack slots, so there are two temporary
|
|
793 // registers (stored in right and temp of the operation).
|
|
794 // the stack allocator must guarantee that the stack slots are really free,
|
|
795 // otherwise there might be a stack overflow.
|
|
796 assert(left->is_fpu_register(), "must be");
|
|
797 assert(res->is_fpu_register(), "must be");
|
|
798 // assert(left->is_last_use(), "old value gets destroyed");
|
|
799 assert(right->is_fpu_register(), "right is used as the first temporary register");
|
|
800 assert(op2->tmp_opr()->is_fpu_register(), "temp is used as the second temporary register");
|
|
801 assert(fpu_num(left) != fpu_num(right) && fpu_num(right) != fpu_num(op2->tmp_opr()) && fpu_num(op2->tmp_opr()) != fpu_num(res), "need distinct temp registers");
|
|
802
|
|
803 insert_free_if_dead(right);
|
|
804 insert_free_if_dead(op2->tmp_opr());
|
|
805
|
|
806 insert_free_if_dead(res, left);
|
|
807 insert_exchange(left);
|
|
808 do_rename(left, res);
|
|
809
|
|
810 new_left = to_fpu_stack_top(res);
|
|
811 new_res = new_left;
|
|
812
|
|
813 op2->set_fpu_stack_size(sim()->stack_size());
|
|
814 assert(sim()->stack_size() <= 6, "at least two stack slots must be free");
|
|
815 break;
|
|
816 }
|
|
817
|
|
818 default: {
|
|
819 assert(false, "missed a fpu-operation");
|
|
820 }
|
|
821 }
|
|
822
|
|
823 op2->set_in_opr1(new_left);
|
|
824 op2->set_in_opr2(new_right);
|
|
825 op2->set_result_opr(new_res);
|
|
826 }
|
|
827
|
|
828 void FpuStackAllocator::handle_opCall(LIR_OpCall* opCall) {
|
|
829 LIR_Opr res = opCall->result_opr();
|
|
830
|
|
831 // clear fpu-stack before call
|
|
832 // it may contain dead values that could not have been remved by previous operations
|
|
833 clear_fpu_stack(LIR_OprFact::illegalOpr);
|
|
834 assert(sim()->is_empty(), "fpu stack must be empty now");
|
|
835
|
|
836 // compute debug information before (possible) fpu result is pushed
|
|
837 compute_debug_information(opCall);
|
|
838
|
|
839 if (res->is_fpu_register() && !res->is_xmm_register()) {
|
|
840 do_push(res);
|
|
841 opCall->set_result_opr(to_fpu_stack_top(res));
|
|
842 }
|
|
843 }
|
|
844
|
|
845 #ifndef PRODUCT
|
|
846 void FpuStackAllocator::check_invalid_lir_op(LIR_Op* op) {
|
|
847 switch (op->code()) {
|
|
848 case lir_24bit_FPU:
|
|
849 case lir_reset_FPU:
|
|
850 case lir_ffree:
|
|
851 assert(false, "operations not allowed in lir. If one of these operations is needed, check if they have fpu operands");
|
|
852 break;
|
|
853
|
|
854 case lir_fpop_raw:
|
|
855 case lir_fxch:
|
|
856 case lir_fld:
|
|
857 assert(false, "operations only inserted by FpuStackAllocator");
|
|
858 break;
|
|
859 }
|
|
860 }
|
|
861 #endif
|
|
862
|
|
863
|
|
864 void FpuStackAllocator::merge_insert_add(LIR_List* instrs, FpuStackSim* cur_sim, int reg) {
|
|
865 LIR_Op1* move = new LIR_Op1(lir_move, LIR_OprFact::doubleConst(0), LIR_OprFact::double_fpu(reg)->make_fpu_stack_offset());
|
|
866
|
|
867 instrs->instructions_list()->push(move);
|
|
868
|
|
869 cur_sim->push(reg);
|
|
870 move->set_result_opr(to_fpu_stack(move->result_opr()));
|
|
871
|
|
872 #ifndef PRODUCT
|
|
873 if (TraceFPUStack) {
|
|
874 tty->print("Added new register: %d New state: ", reg); cur_sim->print(); tty->cr();
|
|
875 }
|
|
876 #endif
|
|
877 }
|
|
878
|
|
879 void FpuStackAllocator::merge_insert_xchg(LIR_List* instrs, FpuStackSim* cur_sim, int slot) {
|
|
880 assert(slot > 0, "no exchange necessary");
|
|
881
|
|
882 LIR_Op1* fxch = new LIR_Op1(lir_fxch, LIR_OprFact::intConst(slot));
|
|
883 instrs->instructions_list()->push(fxch);
|
|
884 cur_sim->swap(slot);
|
|
885
|
|
886 #ifndef PRODUCT
|
|
887 if (TraceFPUStack) {
|
|
888 tty->print("Exchanged register: %d New state: ", cur_sim->get_slot(slot)); cur_sim->print(); tty->cr();
|
|
889 }
|
|
890 #endif
|
|
891 }
|
|
892
|
|
893 void FpuStackAllocator::merge_insert_pop(LIR_List* instrs, FpuStackSim* cur_sim) {
|
|
894 int reg = cur_sim->get_slot(0);
|
|
895
|
|
896 LIR_Op* fpop = new LIR_Op0(lir_fpop_raw);
|
|
897 instrs->instructions_list()->push(fpop);
|
|
898 cur_sim->pop(reg);
|
|
899
|
|
900 #ifndef PRODUCT
|
|
901 if (TraceFPUStack) {
|
|
902 tty->print("Removed register: %d New state: ", reg); cur_sim->print(); tty->cr();
|
|
903 }
|
|
904 #endif
|
|
905 }
|
|
906
|
|
907 bool FpuStackAllocator::merge_rename(FpuStackSim* cur_sim, FpuStackSim* sux_sim, int start_slot, int change_slot) {
|
|
908 int reg = cur_sim->get_slot(change_slot);
|
|
909
|
|
910 for (int slot = start_slot; slot >= 0; slot--) {
|
|
911 int new_reg = sux_sim->get_slot(slot);
|
|
912
|
|
913 if (!cur_sim->contains(new_reg)) {
|
|
914 cur_sim->set_slot(change_slot, new_reg);
|
|
915
|
|
916 #ifndef PRODUCT
|
|
917 if (TraceFPUStack) {
|
|
918 tty->print("Renamed register %d to %d New state: ", reg, new_reg); cur_sim->print(); tty->cr();
|
|
919 }
|
|
920 #endif
|
|
921
|
|
922 return true;
|
|
923 }
|
|
924 }
|
|
925 return false;
|
|
926 }
|
|
927
|
|
928
|
|
929 void FpuStackAllocator::merge_fpu_stack(LIR_List* instrs, FpuStackSim* cur_sim, FpuStackSim* sux_sim) {
|
|
930 #ifndef PRODUCT
|
|
931 if (TraceFPUStack) {
|
|
932 tty->cr();
|
|
933 tty->print("before merging: pred: "); cur_sim->print(); tty->cr();
|
|
934 tty->print(" sux: "); sux_sim->print(); tty->cr();
|
|
935 }
|
|
936
|
|
937 int slot;
|
|
938 for (slot = 0; slot < cur_sim->stack_size(); slot++) {
|
|
939 assert(!cur_sim->slot_is_empty(slot), "not handled by algorithm");
|
|
940 }
|
|
941 for (slot = 0; slot < sux_sim->stack_size(); slot++) {
|
|
942 assert(!sux_sim->slot_is_empty(slot), "not handled by algorithm");
|
|
943 }
|
|
944 #endif
|
|
945
|
|
946 // size difference between cur and sux that must be resolved by adding or removing values form the stack
|
|
947 int size_diff = cur_sim->stack_size() - sux_sim->stack_size();
|
|
948
|
|
949 if (!ComputeExactFPURegisterUsage) {
|
|
950 // add slots that are currently free, but used in successor
|
|
951 // When the exact FPU register usage is computed, the stack does
|
|
952 // not contain dead values at merging -> no values must be added
|
|
953
|
|
954 int sux_slot = sux_sim->stack_size() - 1;
|
|
955 while (size_diff < 0) {
|
|
956 assert(sux_slot >= 0, "slot out of bounds -> error in algorithm");
|
|
957
|
|
958 int reg = sux_sim->get_slot(sux_slot);
|
|
959 if (!cur_sim->contains(reg)) {
|
|
960 merge_insert_add(instrs, cur_sim, reg);
|
|
961 size_diff++;
|
|
962
|
|
963 if (sux_slot + size_diff != 0) {
|
|
964 merge_insert_xchg(instrs, cur_sim, sux_slot + size_diff);
|
|
965 }
|
|
966 }
|
|
967 sux_slot--;
|
|
968 }
|
|
969 }
|
|
970
|
|
971 assert(cur_sim->stack_size() >= sux_sim->stack_size(), "stack size must be equal or greater now");
|
|
972 assert(size_diff == cur_sim->stack_size() - sux_sim->stack_size(), "must be");
|
|
973
|
|
974 // stack merge algorithm:
|
|
975 // 1) as long as the current stack top is not in the right location (that meens
|
|
976 // it should not be on the stack top), exchange it into the right location
|
|
977 // 2) if the stack top is right, but the remaining stack is not ordered correctly,
|
|
978 // the stack top is exchanged away to get another value on top ->
|
|
979 // now step 1) can be continued
|
|
980 // the stack can also contain unused items -> these items are removed from stack
|
|
981
|
|
982 int finished_slot = sux_sim->stack_size() - 1;
|
|
983 while (finished_slot >= 0 || size_diff > 0) {
|
|
984 while (size_diff > 0 || (cur_sim->stack_size() > 0 && cur_sim->get_slot(0) != sux_sim->get_slot(0))) {
|
|
985 int reg = cur_sim->get_slot(0);
|
|
986 if (sux_sim->contains(reg)) {
|
|
987 int sux_slot = sux_sim->offset_from_tos(reg);
|
|
988 merge_insert_xchg(instrs, cur_sim, sux_slot + size_diff);
|
|
989
|
|
990 } else if (!merge_rename(cur_sim, sux_sim, finished_slot, 0)) {
|
|
991 assert(size_diff > 0, "must be");
|
|
992
|
|
993 merge_insert_pop(instrs, cur_sim);
|
|
994 size_diff--;
|
|
995 }
|
|
996 assert(cur_sim->stack_size() == 0 || cur_sim->get_slot(0) != reg, "register must have been changed");
|
|
997 }
|
|
998
|
|
999 while (finished_slot >= 0 && cur_sim->get_slot(finished_slot) == sux_sim->get_slot(finished_slot)) {
|
|
1000 finished_slot--;
|
|
1001 }
|
|
1002
|
|
1003 if (finished_slot >= 0) {
|
|
1004 int reg = cur_sim->get_slot(finished_slot);
|
|
1005
|
|
1006 if (sux_sim->contains(reg) || !merge_rename(cur_sim, sux_sim, finished_slot, finished_slot)) {
|
|
1007 assert(sux_sim->contains(reg) || size_diff > 0, "must be");
|
|
1008 merge_insert_xchg(instrs, cur_sim, finished_slot);
|
|
1009 }
|
|
1010 assert(cur_sim->get_slot(finished_slot) != reg, "register must have been changed");
|
|
1011 }
|
|
1012 }
|
|
1013
|
|
1014 #ifndef PRODUCT
|
|
1015 if (TraceFPUStack) {
|
|
1016 tty->print("after merging: pred: "); cur_sim->print(); tty->cr();
|
|
1017 tty->print(" sux: "); sux_sim->print(); tty->cr();
|
|
1018 tty->cr();
|
|
1019 }
|
|
1020 #endif
|
|
1021 assert(cur_sim->stack_size() == sux_sim->stack_size(), "stack size must be equal now");
|
|
1022 }
|
|
1023
|
|
1024
|
|
1025 void FpuStackAllocator::merge_cleanup_fpu_stack(LIR_List* instrs, FpuStackSim* cur_sim, BitMap& live_fpu_regs) {
|
|
1026 #ifndef PRODUCT
|
|
1027 if (TraceFPUStack) {
|
|
1028 tty->cr();
|
|
1029 tty->print("before cleanup: state: "); cur_sim->print(); tty->cr();
|
|
1030 tty->print(" live: "); live_fpu_regs.print_on(tty); tty->cr();
|
|
1031 }
|
|
1032 #endif
|
|
1033
|
|
1034 int slot = 0;
|
|
1035 while (slot < cur_sim->stack_size()) {
|
|
1036 int reg = cur_sim->get_slot(slot);
|
|
1037 if (!live_fpu_regs.at(reg)) {
|
|
1038 if (slot != 0) {
|
|
1039 merge_insert_xchg(instrs, cur_sim, slot);
|
|
1040 }
|
|
1041 merge_insert_pop(instrs, cur_sim);
|
|
1042 } else {
|
|
1043 slot++;
|
|
1044 }
|
|
1045 }
|
|
1046
|
|
1047 #ifndef PRODUCT
|
|
1048 if (TraceFPUStack) {
|
|
1049 tty->print("after cleanup: state: "); cur_sim->print(); tty->cr();
|
|
1050 tty->print(" live: "); live_fpu_regs.print_on(tty); tty->cr();
|
|
1051 tty->cr();
|
|
1052 }
|
|
1053
|
|
1054 // check if fpu stack only contains live registers
|
|
1055 for (unsigned int i = 0; i < live_fpu_regs.size(); i++) {
|
|
1056 if (live_fpu_regs.at(i) != cur_sim->contains(i)) {
|
|
1057 tty->print_cr("mismatch between required and actual stack content");
|
|
1058 break;
|
|
1059 }
|
|
1060 }
|
|
1061 #endif
|
|
1062 }
|
|
1063
|
|
1064
|
|
1065 bool FpuStackAllocator::merge_fpu_stack_with_successors(BlockBegin* block) {
|
|
1066 #ifndef PRODUCT
|
|
1067 if (TraceFPUStack) {
|
|
1068 tty->print_cr("Propagating FPU stack state for B%d at LIR_Op position %d to successors:",
|
|
1069 block->block_id(), pos());
|
|
1070 sim()->print();
|
|
1071 tty->cr();
|
|
1072 }
|
|
1073 #endif
|
|
1074
|
|
1075 bool changed = false;
|
|
1076 int number_of_sux = block->number_of_sux();
|
|
1077
|
|
1078 if (number_of_sux == 1 && block->sux_at(0)->number_of_preds() > 1) {
|
|
1079 // The successor has at least two incoming edges, so a stack merge will be necessary
|
|
1080 // If this block is the first predecessor, cleanup the current stack and propagate it
|
|
1081 // If this block is not the first predecessor, a stack merge will be necessary
|
|
1082
|
|
1083 BlockBegin* sux = block->sux_at(0);
|
|
1084 intArray* state = sux->fpu_stack_state();
|
|
1085 LIR_List* instrs = new LIR_List(_compilation);
|
|
1086
|
|
1087 if (state != NULL) {
|
|
1088 // Merge with a successors that already has a FPU stack state
|
|
1089 // the block must only have one successor because critical edges must been split
|
|
1090 FpuStackSim* cur_sim = sim();
|
|
1091 FpuStackSim* sux_sim = temp_sim();
|
|
1092 sux_sim->read_state(state);
|
|
1093
|
|
1094 merge_fpu_stack(instrs, cur_sim, sux_sim);
|
|
1095
|
|
1096 } else {
|
|
1097 // propagate current FPU stack state to successor without state
|
|
1098 // clean up stack first so that there are no dead values on the stack
|
|
1099 if (ComputeExactFPURegisterUsage) {
|
|
1100 FpuStackSim* cur_sim = sim();
|
|
1101 BitMap live_fpu_regs = block->sux_at(0)->fpu_register_usage();
|
|
1102 assert(live_fpu_regs.size() == FrameMap::nof_fpu_regs, "missing register usage");
|
|
1103
|
|
1104 merge_cleanup_fpu_stack(instrs, cur_sim, live_fpu_regs);
|
|
1105 }
|
|
1106
|
|
1107 intArray* state = sim()->write_state();
|
|
1108 if (TraceFPUStack) {
|
|
1109 tty->print_cr("Setting FPU stack state of B%d (merge path)", sux->block_id());
|
|
1110 sim()->print(); tty->cr();
|
|
1111 }
|
|
1112 sux->set_fpu_stack_state(state);
|
|
1113 }
|
|
1114
|
|
1115 if (instrs->instructions_list()->length() > 0) {
|
|
1116 lir()->insert_before(pos(), instrs);
|
|
1117 set_pos(instrs->instructions_list()->length() + pos());
|
|
1118 changed = true;
|
|
1119 }
|
|
1120
|
|
1121 } else {
|
|
1122 // Propagate unmodified Stack to successors where a stack merge is not necessary
|
|
1123 intArray* state = sim()->write_state();
|
|
1124 for (int i = 0; i < number_of_sux; i++) {
|
|
1125 BlockBegin* sux = block->sux_at(i);
|
|
1126
|
|
1127 #ifdef ASSERT
|
|
1128 for (int j = 0; j < sux->number_of_preds(); j++) {
|
|
1129 assert(block == sux->pred_at(j), "all critical edges must be broken");
|
|
1130 }
|
|
1131
|
|
1132 // check if new state is same
|
|
1133 if (sux->fpu_stack_state() != NULL) {
|
|
1134 intArray* sux_state = sux->fpu_stack_state();
|
|
1135 assert(state->length() == sux_state->length(), "overwriting existing stack state");
|
|
1136 for (int j = 0; j < state->length(); j++) {
|
|
1137 assert(state->at(j) == sux_state->at(j), "overwriting existing stack state");
|
|
1138 }
|
|
1139 }
|
|
1140 #endif
|
|
1141 #ifndef PRODUCT
|
|
1142 if (TraceFPUStack) {
|
|
1143 tty->print_cr("Setting FPU stack state of B%d", sux->block_id());
|
|
1144 sim()->print(); tty->cr();
|
|
1145 }
|
|
1146 #endif
|
|
1147
|
|
1148 sux->set_fpu_stack_state(state);
|
|
1149 }
|
|
1150 }
|
|
1151
|
|
1152 #ifndef PRODUCT
|
|
1153 // assertions that FPU stack state conforms to all successors' states
|
|
1154 intArray* cur_state = sim()->write_state();
|
|
1155 for (int i = 0; i < number_of_sux; i++) {
|
|
1156 BlockBegin* sux = block->sux_at(i);
|
|
1157 intArray* sux_state = sux->fpu_stack_state();
|
|
1158
|
|
1159 assert(sux_state != NULL, "no fpu state");
|
|
1160 assert(cur_state->length() == sux_state->length(), "incorrect length");
|
|
1161 for (int i = 0; i < cur_state->length(); i++) {
|
|
1162 assert(cur_state->at(i) == sux_state->at(i), "element not equal");
|
|
1163 }
|
|
1164 }
|
|
1165 #endif
|
|
1166
|
|
1167 return changed;
|
|
1168 }
|