1 /* 2 * Copyright (c) 1998, 2014, 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 #ifndef SHARE_VM_CODE_VMREG_HPP 26 #define SHARE_VM_CODE_VMREG_HPP 27 28 #include "asm/register.hpp" 29 #include "memory/allocation.hpp" 30 #include "utilities/globalDefinitions.hpp" 31 32 #ifdef COMPILER2 33 #include "opto/adlcVMDeps.hpp" 34 #include "utilities/ostream.hpp" 35 #endif 36 37 //------------------------------VMReg------------------------------------------ 38 // The VM uses 'unwarped' stack slots; the compiler uses 'warped' stack slots. 39 // Register numbers below VMRegImpl::stack0 are the same for both. Register 40 // numbers above stack0 are either warped (in the compiler) or unwarped 41 // (in the VM). Unwarped numbers represent stack indices, offsets from 42 // the current stack pointer. Warped numbers are required during compilation 43 // when we do not yet know how big the frame will be. 44 45 class VMRegImpl; 46 typedef VMRegImpl* VMReg; 47 48 class VMRegImpl { 49 // friend class OopMap; 50 friend class VMStructs; 51 friend class OptoReg; 52 // friend class Location; 53 private: 54 enum { 55 BAD_REG = -1 56 }; 57 58 59 60 static VMReg stack0; 61 // Names for registers 62 static const char *regName[]; 63 static const int register_count; 64 65 66 public: 67 68 static VMReg as_VMReg(int val, bool bad_ok = false) { assert(val > BAD_REG || bad_ok, "invalid"); return (VMReg) (intptr_t) val; } 69 70 const char* name() { 71 if (is_reg()) { 72 return regName[value()]; 73 } else if (!is_valid()) { 74 return "BAD"; 75 } else { 76 // shouldn't really be called with stack 77 return "STACKED REG"; 78 } 79 } 80 static VMReg Bad() { return (VMReg) (intptr_t) BAD_REG; } 81 bool is_valid() const { return ((intptr_t) this) != BAD_REG; } 82 bool is_stack() const { return (intptr_t) this >= (intptr_t) stack0; } 83 bool is_reg() const { return is_valid() && !is_stack(); } 84 85 // A concrete register is a value that returns true for is_reg() and is 86 // also a register you could use in the assembler. On machines with 87 // 64bit registers only one half of the VMReg (and OptoReg) is considered 88 // concrete. 89 // bool is_concrete(); 90 91 // VMRegs are 4 bytes wide on all platforms 92 static const int stack_slot_size; 93 static const int slots_per_word; 94 95 96 // This really ought to check that the register is "real" in the sense that 97 // we don't try and get the VMReg number of a physical register that doesn't 98 // have an expressible part. That would be pd specific code 99 VMReg next() { 100 assert((is_reg() && value() < stack0->value() - 1) || is_stack(), "must be"); 101 return (VMReg)(intptr_t)(value() + 1); 102 } 103 VMReg next(int i) { 104 assert((is_reg() && value() < stack0->value() - i) || is_stack(), "must be"); 105 return (VMReg)(intptr_t)(value() + i); 106 } 107 VMReg prev() { 108 assert((is_stack() && value() > stack0->value()) || (is_reg() && value() != 0), "must be"); 109 return (VMReg)(intptr_t)(value() - 1); 110 } 111 112 113 intptr_t value() const {return (intptr_t) this; } 114 115 void print_on(outputStream* st) const; 116 void print() const { print_on(tty); } 117 118 // bias a stack slot. 119 // Typically used to adjust a virtual frame slots by amounts that are offset by 120 // amounts that are part of the native abi. The VMReg must be a stack slot 121 // and the result must be also. 122 123 VMReg bias(int offset) { 124 assert(is_stack(), "must be"); 125 // VMReg res = VMRegImpl::as_VMReg(value() + offset); 126 VMReg res = stack2reg(reg2stack() + offset); 127 assert(res->is_stack(), "must be"); 128 return res; 129 } 130 131 // Convert register numbers to stack slots and vice versa 132 static VMReg stack2reg( int idx ) { 133 return (VMReg) (intptr_t) (stack0->value() + idx); 134 } 135 136 uintptr_t reg2stack() { 137 assert( is_stack(), "Not a stack-based register" ); 138 return value() - stack0->value(); 139 } 140 141 static void set_regName(); 142 143 #ifdef TARGET_ARCH_x86 144 # include "vmreg_x86.hpp" 145 #endif 146 #ifdef TARGET_ARCH_sparc 147 # include "vmreg_sparc.hpp" 148 #endif 149 #ifdef TARGET_ARCH_zero 150 # include "vmreg_zero.hpp" 151 #endif 152 #ifdef TARGET_ARCH_arm 153 # include "vmreg_arm.hpp" 154 #endif 155 #ifdef TARGET_ARCH_ppc 156 # include "vmreg_ppc.hpp" 157 #endif 158 159 160 }; 161 162 //---------------------------VMRegPair------------------------------------------- 163 // Pairs of 32-bit registers for arguments. 164 // SharedRuntime::java_calling_convention will overwrite the structs with 165 // the calling convention's registers. VMRegImpl::Bad is returned for any 166 // unused 32-bit register. This happens for the unused high half of Int 167 // arguments, or for 32-bit pointers or for longs in the 32-bit sparc build 168 // (which are passed to natives in low 32-bits of e.g. O0/O1 and the high 169 // 32-bits of O0/O1 are set to VMRegImpl::Bad). Longs in one register & doubles 170 // always return a high and a low register, as do 64-bit pointers. 171 // 172 class VMRegPair { 173 private: 174 VMReg _second; 175 VMReg _first; 176 public: 177 void set_bad ( ) { _second=VMRegImpl::Bad(); _first=VMRegImpl::Bad(); } 178 void set1 ( VMReg v ) { _second=VMRegImpl::Bad(); _first=v; } 179 void set2 ( VMReg v ) { _second=v->next(); _first=v; } 180 void set_pair( VMReg second, VMReg first ) { _second= second; _first= first; } 181 void set_ptr ( VMReg ptr ) { 182 #ifdef _LP64 183 _second = ptr->next(); 184 #else 185 _second = VMRegImpl::Bad(); 186 #endif 187 _first = ptr; 188 } 189 // Return true if single register, even if the pair is really just adjacent stack slots 190 bool is_single_reg() const { 191 return (_first->is_valid()) && (_first->value() + 1 == _second->value()); 192 } 193 194 // Return true if single stack based "register" where the slot alignment matches input alignment 195 bool is_adjacent_on_stack(int alignment) const { 196 return (_first->is_stack() && (_first->value() + 1 == _second->value()) && ((_first->value() & (alignment-1)) == 0)); 197 } 198 199 // Return true if single stack based "register" where the slot alignment matches input alignment 200 bool is_adjacent_aligned_on_stack(int alignment) const { 201 return (_first->is_stack() && (_first->value() + 1 == _second->value()) && ((_first->value() & (alignment-1)) == 0)); 202 } 203 204 // Return true if single register but adjacent stack slots do not count 205 bool is_single_phys_reg() const { 206 return (_first->is_reg() && (_first->value() + 1 == _second->value())); 207 } 208 209 VMReg second() const { return _second; } 210 VMReg first() const { return _first; } 211 VMRegPair(VMReg s, VMReg f) { _second = s; _first = f; } 212 VMRegPair(VMReg f) { _second = VMRegImpl::Bad(); _first = f; } 213 VMRegPair() { _second = VMRegImpl::Bad(); _first = VMRegImpl::Bad(); } 214 }; 215 216 #endif // SHARE_VM_CODE_VMREG_HPP