1 /*
2 * Copyright (c) 1998, 2017, 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 "asm/macroAssembler.hpp"
27 #include "code/relocInfo.hpp"
28 #include "nativeInst_x86.hpp"
29 #include "oops/compressedOops.inline.hpp"
30 #include "oops/klass.inline.hpp"
31 #include "oops/oop.inline.hpp"
32 #include "runtime/safepoint.hpp"
33 #include "runtime/safepointMechanism.hpp"
34
35
36 void Relocation::pd_set_data_value(address x, intptr_t o, bool verify_only) {
37 #ifdef AMD64
38 x += o;
39 typedef Assembler::WhichOperand WhichOperand;
40 WhichOperand which = (WhichOperand) format(); // that is, disp32 or imm, call32, narrow oop
41 assert(which == Assembler::disp32_operand ||
42 which == Assembler::narrow_oop_operand ||
43 which == Assembler::imm_operand, "format unpacks ok");
44 if (which == Assembler::imm_operand) {
45 if (verify_only) {
46 guarantee(*pd_address_in_code() == x, "instructions must match");
47 } else {
48 *pd_address_in_code() = x;
49 }
50 } else if (which == Assembler::narrow_oop_operand) {
51 address disp = Assembler::locate_operand(addr(), which);
52 // both compressed oops and compressed classes look the same
53 if (Universe::heap()->is_in_reserved((oop)x)) {
54 if (verify_only) {
55 guarantee(*(uint32_t*) disp == CompressedOops::encode((oop)x), "instructions must match");
56 } else {
57 *(int32_t*) disp = CompressedOops::encode((oop)x);
58 }
59 } else {
60 if (verify_only) {
61 guarantee(*(uint32_t*) disp == Klass::encode_klass((Klass*)x), "instructions must match");
62 } else {
63 *(int32_t*) disp = Klass::encode_klass((Klass*)x);
64 }
65 }
66 } else {
67 // Note: Use runtime_call_type relocations for call32_operand.
68 address ip = addr();
69 address disp = Assembler::locate_operand(ip, which);
70 address next_ip = Assembler::locate_next_instruction(ip);
71 if (verify_only) {
72 guarantee(*(int32_t*) disp == (x - next_ip), "instructions must match");
73 } else {
74 *(int32_t*) disp = x - next_ip;
75 }
76 }
77 #else
78 if (verify_only) {
79 guarantee(*pd_address_in_code() == (x + o), "instructions must match");
80 } else {
81 *pd_address_in_code() = x + o;
82 }
83 #endif // AMD64
84 }
85
86
87 address Relocation::pd_call_destination(address orig_addr) {
88 intptr_t adj = 0;
89 if (orig_addr != NULL) {
90 // We just moved this call instruction from orig_addr to addr().
91 // This means its target will appear to have grown by addr() - orig_addr.
92 adj = -( addr() - orig_addr );
93 }
94 NativeInstruction* ni = nativeInstruction_at(addr());
95 if (ni->is_call()) {
96 return nativeCall_at(addr())->destination() + adj;
97 } else if (ni->is_jump()) {
98 return nativeJump_at(addr())->jump_destination() + adj;
99 } else if (ni->is_cond_jump()) {
100 return nativeGeneralJump_at(addr())->jump_destination() + adj;
101 } else if (ni->is_mov_literal64()) {
102 return (address) ((NativeMovConstReg*)ni)->data();
103 } else {
104 ShouldNotReachHere();
105 return NULL;
106 }
107 }
108
109
110 void Relocation::pd_set_call_destination(address x) {
111 NativeInstruction* ni = nativeInstruction_at(addr());
112 if (ni->is_call()) {
113 nativeCall_at(addr())->set_destination(x);
114 } else if (ni->is_jump()) {
115 NativeJump* nj = nativeJump_at(addr());
116
117 // Unresolved jumps are recognized by a destination of -1
118 // However 64bit can't actually produce such an address
119 // and encodes a jump to self but jump_destination will
120 // return a -1 as the signal. We must not relocate this
121 // jmp or the ic code will not see it as unresolved.
122
123 if (nj->jump_destination() == (address) -1) {
124 x = addr(); // jump to self
125 }
126 nj->set_jump_destination(x);
127 } else if (ni->is_cond_jump()) {
128 // %%%% kludge this, for now, until we get a jump_destination method
129 address old_dest = nativeGeneralJump_at(addr())->jump_destination();
130 address disp = Assembler::locate_operand(addr(), Assembler::call32_operand);
131 *(jint*)disp += (x - old_dest);
132 } else if (ni->is_mov_literal64()) {
133 ((NativeMovConstReg*)ni)->set_data((intptr_t)x);
134 } else {
135 ShouldNotReachHere();
136 }
137 }
138
139
140 address* Relocation::pd_address_in_code() {
141 // All embedded Intel addresses are stored in 32-bit words.
142 // Since the addr points at the start of the instruction,
143 // we must parse the instruction a bit to find the embedded word.
144 assert(is_data(), "must be a DataRelocation");
145 typedef Assembler::WhichOperand WhichOperand;
146 WhichOperand which = (WhichOperand) format(); // that is, disp32 or imm/imm32
147 #ifdef AMD64
148 assert(which == Assembler::disp32_operand ||
149 which == Assembler::call32_operand ||
150 which == Assembler::imm_operand, "format unpacks ok");
151 // The "address" in the code is a displacement can't return it as
152 // and address* since it is really a jint*
153 guarantee(which == Assembler::imm_operand, "must be immediate operand");
154 #else
155 assert(which == Assembler::disp32_operand || which == Assembler::imm_operand, "format unpacks ok");
156 #endif // AMD64
157 return (address*) Assembler::locate_operand(addr(), which);
158 }
159
160
161 address Relocation::pd_get_address_from_code() {
162 #ifdef AMD64
163 // All embedded Intel addresses are stored in 32-bit words.
164 // Since the addr points at the start of the instruction,
165 // we must parse the instruction a bit to find the embedded word.
166 assert(is_data(), "must be a DataRelocation");
167 typedef Assembler::WhichOperand WhichOperand;
168 WhichOperand which = (WhichOperand) format(); // that is, disp32 or imm/imm32
169 assert(which == Assembler::disp32_operand ||
170 which == Assembler::call32_operand ||
171 which == Assembler::imm_operand, "format unpacks ok");
172 if (which != Assembler::imm_operand) {
173 address ip = addr();
174 address disp = Assembler::locate_operand(ip, which);
175 address next_ip = Assembler::locate_next_instruction(ip);
176 address a = next_ip + *(int32_t*) disp;
177 return a;
178 }
179 #endif // AMD64
180 return *pd_address_in_code();
181 }
182
183 void poll_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
184 #ifdef _LP64
185 typedef Assembler::WhichOperand WhichOperand;
186 WhichOperand which = (WhichOperand) format();
187 #if !INCLUDE_JVMCI
188 if (SafepointMechanism::uses_global_page_poll()) {
189 assert((which == Assembler::disp32_operand) == !Assembler::is_polling_page_far(), "format not set correctly");
190 }
191 #endif
192 if (which == Assembler::disp32_operand) {
193 assert(SafepointMechanism::uses_global_page_poll(), "should only have generated such a poll if global polling enabled");
194 address orig_addr = old_addr_for(addr(), src, dest);
195 NativeInstruction* oni = nativeInstruction_at(orig_addr);
196 int32_t* orig_disp = (int32_t*) Assembler::locate_operand(orig_addr, which);
197 // This poll_addr is incorrect by the size of the instruction it is irrelevant
198 intptr_t poll_addr = (intptr_t)oni + *orig_disp;
199 NativeInstruction* ni = nativeInstruction_at(addr());
200 intptr_t new_disp = poll_addr - (intptr_t) ni;
201
202 int32_t* disp = (int32_t*) Assembler::locate_operand(addr(), which);
203 * disp = (int32_t)new_disp;
204 }
205 #endif // _LP64
206 }
207
208 void metadata_Relocation::pd_fix_value(address x) {
209 }