1 /* 2 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "c1/c1_FpuStackSim.hpp" 27 #include "c1/c1_FrameMap.hpp" 28 #include "utilities/array.hpp" 29 #include "utilities/ostream.hpp" 30 31 //-------------------------------------------------------- 32 // FpuStackSim 33 //-------------------------------------------------------- 34 35 // This class maps the FPU registers to their stack locations; it computes 36 // the offsets between individual registers and simulates the FPU stack. 37 38 const int EMPTY = -1; 39 40 int FpuStackSim::regs_at(int i) const { 41 assert(i >= 0 && i < FrameMap::nof_fpu_regs, "out of bounds"); 42 return _regs[i]; 43 } 44 45 void FpuStackSim::set_regs_at(int i, int val) { 46 assert(i >= 0 && i < FrameMap::nof_fpu_regs, "out of bounds"); 47 _regs[i] = val; 48 } 49 50 void FpuStackSim::dec_stack_size() { 51 _stack_size--; 52 assert(_stack_size >= 0, "FPU stack underflow"); 53 } 54 55 void FpuStackSim::inc_stack_size() { 56 _stack_size++; 57 assert(_stack_size <= FrameMap::nof_fpu_regs, "FPU stack overflow"); 58 } 59 60 FpuStackSim::FpuStackSim(Compilation* compilation) 61 : _compilation(compilation) 62 { 63 _stack_size = 0; 64 for (int i = 0; i < FrameMap::nof_fpu_regs; i++) { 65 set_regs_at(i, EMPTY); 66 } 67 } 68 69 70 void FpuStackSim::pop() { 71 if (TraceFPUStack) { tty->print("FPU-pop "); print(); tty->cr(); } 72 set_regs_at(tos_index(), EMPTY); 73 dec_stack_size(); 74 } 75 76 void FpuStackSim::pop(int rnr) { 77 if (TraceFPUStack) { tty->print("FPU-pop %d", rnr); print(); tty->cr(); } 78 assert(regs_at(tos_index()) == rnr, "rnr is not on TOS"); 79 set_regs_at(tos_index(), EMPTY); 80 dec_stack_size(); 81 } 82 83 84 void FpuStackSim::push(int rnr) { 85 if (TraceFPUStack) { tty->print("FPU-push %d", rnr); print(); tty->cr(); } 86 assert(regs_at(stack_size()) == EMPTY, "should be empty"); 87 set_regs_at(stack_size(), rnr); 88 inc_stack_size(); 89 } 90 91 92 void FpuStackSim::swap(int offset) { 93 if (TraceFPUStack) { tty->print("FPU-swap %d", offset); print(); tty->cr(); } 94 int t = regs_at(tos_index() - offset); 95 set_regs_at(tos_index() - offset, regs_at(tos_index())); 96 set_regs_at(tos_index(), t); 97 } 98 99 100 int FpuStackSim::offset_from_tos(int rnr) const { 101 for (int i = tos_index(); i >= 0; i--) { 102 if (regs_at(i) == rnr) { 103 return tos_index() - i; 104 } 105 } 106 assert(false, "FpuStackSim: register not found"); 107 BAILOUT_("FpuStackSim: register not found", 0); 108 } 109 110 111 int FpuStackSim::get_slot(int tos_offset) const { 112 return regs_at(tos_index() - tos_offset); 113 } 114 115 void FpuStackSim::set_slot(int tos_offset, int rnr) { 116 set_regs_at(tos_index() - tos_offset, rnr); 117 } 118 119 void FpuStackSim::rename(int old_rnr, int new_rnr) { 120 if (TraceFPUStack) { tty->print("FPU-rename %d %d", old_rnr, new_rnr); print(); tty->cr(); } 121 if (old_rnr == new_rnr) 122 return; 123 bool found = false; 124 for (int i = 0; i < stack_size(); i++) { 125 assert(regs_at(i) != new_rnr, "should not see old occurrences of new_rnr on the stack"); 126 if (regs_at(i) == old_rnr) { 127 set_regs_at(i, new_rnr); 128 found = true; 129 } 130 } 131 assert(found, "should have found at least one instance of old_rnr"); 132 } 133 134 135 bool FpuStackSim::contains(int rnr) { 136 for (int i = 0; i < stack_size(); i++) { 137 if (regs_at(i) == rnr) { 138 return true; 139 } 140 } 141 return false; 142 } 143 144 bool FpuStackSim::is_empty() { 145 #ifdef ASSERT 146 if (stack_size() == 0) { 147 for (int i = 0; i < FrameMap::nof_fpu_regs; i++) { 148 assert(regs_at(i) == EMPTY, "must be empty"); 149 } 150 } 151 #endif 152 return stack_size() == 0; 153 } 154 155 156 bool FpuStackSim::slot_is_empty(int tos_offset) { 157 return (regs_at(tos_index() - tos_offset) == EMPTY); 158 } 159 160 161 void FpuStackSim::clear() { 162 if (TraceFPUStack) { tty->print("FPU-clear"); print(); tty->cr(); } 163 for (int i = tos_index(); i >= 0; i--) { 164 set_regs_at(i, EMPTY); 165 } 166 _stack_size = 0; 167 } 168 169 170 intArray* FpuStackSim::write_state() { 171 intArray* res = new intArray(1 + FrameMap::nof_fpu_regs); 172 (*res)[0] = stack_size(); 173 for (int i = 0; i < FrameMap::nof_fpu_regs; i++) { 174 (*res)[1 + i] = regs_at(i); 175 } 176 return res; 177 } 178 179 180 void FpuStackSim::read_state(intArray* fpu_stack_state) { 181 _stack_size = (*fpu_stack_state)[0]; 182 for (int i = 0; i < FrameMap::nof_fpu_regs; i++) { 183 set_regs_at(i, (*fpu_stack_state)[1 + i]); 184 } 185 } 186 187 188 #ifndef PRODUCT 189 void FpuStackSim::print() { 190 tty->print(" N=%d[", stack_size());\ 191 for (int i = 0; i < stack_size(); i++) { 192 int reg = regs_at(i); 193 if (reg != EMPTY) { 194 tty->print("%d", reg); 195 } else { 196 tty->print("_"); 197 } 198 }; 199 tty->print(" ]"); 200 } 201 #endif