1 /*
2 * Copyright (c) 2006, 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_OPTO_OPTOREG_HPP
26 #define SHARE_VM_OPTO_OPTOREG_HPP
27
28 // AdGlobals contains c2 specific register handling code as specified
29 // in the .ad files.
30 #ifdef TARGET_ARCH_MODEL_x86_32
31 # include "adfiles/adGlobals_x86_32.hpp"
32 #endif
33 #ifdef TARGET_ARCH_MODEL_x86_64
34 # include "adfiles/adGlobals_x86_64.hpp"
35 #endif
36 #ifdef TARGET_ARCH_MODEL_sparc
37 # include "adfiles/adGlobals_sparc.hpp"
38 #endif
39 #ifdef TARGET_ARCH_MODEL_zero
40 # include "adfiles/adGlobals_zero.hpp"
41 #endif
42 #ifdef TARGET_ARCH_MODEL_arm
43 # include "adfiles/adGlobals_arm.hpp"
44 #endif
45 #ifdef TARGET_ARCH_MODEL_ppc_32
46 # include "adfiles/adGlobals_ppc_32.hpp"
47 #endif
48 #ifdef TARGET_ARCH_MODEL_ppc_64
49 # include "adfiles/adGlobals_ppc_64.hpp"
50 #endif
51 #ifdef TARGET_ARCH_MODEL_aarch64
52 # include "adfiles/adGlobals_aarch64.hpp"
53 #endif
54
55 //------------------------------OptoReg----------------------------------------
56 // We eventually need Registers for the Real World. Registers are essentially
57 // non-SSA names. A Register is represented as a number. Non-regular values
58 // (e.g., Control, Memory, I/O) use the Special register. The actual machine
59 // registers (as described in the ADL file for a machine) start at zero.
60 // Stack-slots (spill locations) start at the nest Chunk past the last machine
61 // register.
62 //
63 // Note that stack spill-slots are treated as a very large register set.
64 // They have all the correct properties for a Register: not aliased (unique
65 // named). There is some simple mapping from a stack-slot register number
66 // to the actual location on the stack; this mapping depends on the calling
67 // conventions and is described in the ADL.
68 //
69 // Note that Name is not enum. C++ standard defines that the range of enum
70 // is the range of smallest bit-field that can represent all enumerators
71 // declared in the enum. The result of assigning a value to enum is undefined
72 // if the value is outside the enumeration's valid range. OptoReg::Name is
73 // typedef'ed as int, because it needs to be able to represent spill-slots.
74 //
75 class OptoReg VALUE_OBJ_CLASS_SPEC {
76
77 friend class C2Compiler;
78 public:
79 typedef int Name;
80 enum {
81 // Chunk 0
82 Physical = AdlcVMDeps::Physical, // Start of physical regs
83 // A few oddballs at the edge of the world
84 Special = -2, // All special (not allocated) values
85 Bad = -1 // Not a register
86 };
87
88 private:
89
90 static const VMReg opto2vm[REG_COUNT];
91 static Name vm2opto[ConcreteRegisterImpl::number_of_registers];
92
93 public:
94
95 // Stack pointer register
96 static OptoReg::Name c_frame_pointer;
97
98
99
100 // Increment a register number. As in:
101 // "for ( OptoReg::Name i; i=Control; i = add(i,1) ) ..."
102 static Name add( Name x, int y ) { return Name(x+y); }
103
104 // (We would like to have an operator+ for RegName, but it is not
105 // a class, so this would be illegal in C++.)
106
107 static void dump(int, outputStream *st = tty);
108
109 // Get the stack slot number of an OptoReg::Name
110 static unsigned int reg2stack( OptoReg::Name r) {
111 assert( r >= stack0(), " must be");
112 return r - stack0();
113 }
114
115 // convert a stack slot number into an OptoReg::Name
116 static OptoReg::Name stack2reg( int idx) {
117 return Name(stack0() + idx);
118 }
119
120 static bool is_stack(Name n) {
121 return n >= stack0();
122 }
123
124 static bool is_valid(Name n) {
125 return (n != Bad);
126 }
127
128 static bool is_reg(Name n) {
129 return is_valid(n) && !is_stack(n);
130 }
131
132 static VMReg as_VMReg(OptoReg::Name n) {
133 if (is_reg(n)) {
134 // Must use table, it'd be nice if Bad was indexable...
135 return opto2vm[n];
136 } else {
137 assert(!is_stack(n), "must un warp");
138 return VMRegImpl::Bad();
139 }
140 }
141
142 // Can un-warp a stack slot or convert a register or Bad
143 static VMReg as_VMReg(OptoReg::Name n, int frame_size, int arg_count) {
144 if (is_reg(n)) {
145 // Must use table, it'd be nice if Bad was indexable...
146 return opto2vm[n];
147 } else if (is_stack(n)) {
148 int stack_slot = reg2stack(n);
149 if (stack_slot < arg_count) {
150 return VMRegImpl::stack2reg(stack_slot + frame_size);
151 }
152 return VMRegImpl::stack2reg(stack_slot - arg_count);
153 // return return VMRegImpl::stack2reg(reg2stack(OptoReg::add(n, -arg_count)));
154 } else {
155 return VMRegImpl::Bad();
156 }
157 }
158
159 static OptoReg::Name as_OptoReg(VMReg r) {
160 if (r->is_stack()) {
161 assert(false, "must warp");
162 return stack2reg(r->reg2stack());
163 } else if (r->is_valid()) {
164 // Must use table, it'd be nice if Bad was indexable...
165 return vm2opto[r->value()];
166 } else {
167 return Bad;
168 }
169 }
170
171 static OptoReg::Name stack0() {
172 return VMRegImpl::stack0->value();
173 }
174
175 static const char* regname(OptoReg::Name n) {
176 return as_VMReg(n)->name();
177 }
178
179 };
180
181 //---------------------------OptoRegPair-------------------------------------------
182 // Pairs of 32-bit registers for the allocator.
183 // This is a very similar class to VMRegPair. C2 only interfaces with VMRegPair
184 // via the calling convention code which is shared between the compilers.
185 // Since C2 uses OptoRegs for register allocation it is more efficient to use
186 // VMRegPair internally for nodes that can contain a pair of OptoRegs rather
187 // than use VMRegPair and continually be converting back and forth. So normally
188 // C2 will take in a VMRegPair from the calling convention code and immediately
189 // convert them to an OptoRegPair and stay in the OptoReg world. The only over
190 // conversion between OptoRegs and VMRegs is for debug info and oopMaps. This
191 // is not a high bandwidth spot and so it is not an issue.
192 // Note that onde other consequence of staying in the OptoReg world with OptoRegPairs
193 // is that there are "physical" OptoRegs that are not representable in the VMReg
194 // world, notably flags. [ But by design there is "space" in the VMReg world
195 // for such registers they just may not be concrete ]. So if we were to use VMRegPair
196 // then the VMReg world would have to have a representation for these registers
197 // so that a OptoReg->VMReg->OptoReg would reproduce ther original OptoReg. As it
198 // stands if you convert a flag (condition code) to a VMReg you will get VMRegImpl::Bad
199 // and converting that will return OptoReg::Bad losing the identity of the OptoReg.
200
201 class OptoRegPair {
202 friend class VMStructs;
203 private:
204 short _second;
205 short _first;
206 public:
207 void set_bad ( ) { _second = OptoReg::Bad; _first = OptoReg::Bad; }
208 void set1 ( OptoReg::Name n ) { _second = OptoReg::Bad; _first = n; }
209 void set2 ( OptoReg::Name n ) { _second = n + 1; _first = n; }
210 void set_pair( OptoReg::Name second, OptoReg::Name first ) { _second= second; _first= first; }
211 void set_ptr ( OptoReg::Name ptr ) {
212 #ifdef _LP64
213 _second = ptr+1;
214 #else
215 _second = OptoReg::Bad;
216 #endif
217 _first = ptr;
218 }
219
220 OptoReg::Name second() const { return _second; }
221 OptoReg::Name first() const { return _first; }
222 OptoRegPair(OptoReg::Name second, OptoReg::Name first) { _second = second; _first = first; }
223 OptoRegPair(OptoReg::Name f) { _second = OptoReg::Bad; _first = f; }
224 OptoRegPair() { _second = OptoReg::Bad; _first = OptoReg::Bad; }
225 };
226
227 #endif // SHARE_VM_OPTO_OPTOREG_HPP