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