1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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  *
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17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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24 
25 #include "precompiled.hpp"
26 #include "asm/macroAssembler.hpp"
27 #include "code/relocInfo.hpp"
28 #include "nativeInst_x86.hpp"
29 #include "oops/oop.inline.hpp"
30 #include "runtime/safepoint.hpp"
31 
32 
pd_set_data_value(address x,intptr_t o,bool verify_only)33 void Relocation::pd_set_data_value(address x, intptr_t o, bool verify_only) {
34 #ifdef AMD64
35   x += o;
36   typedef Assembler::WhichOperand WhichOperand;
37   WhichOperand which = (WhichOperand) format(); // that is, disp32 or imm, call32, narrow oop
38   assert(which == Assembler::disp32_operand ||
39          which == Assembler::narrow_oop_operand ||
40          which == Assembler::imm_operand, "format unpacks ok");
41   if (which == Assembler::imm_operand) {
42     if (verify_only) {
43       guarantee(*pd_address_in_code() == x, "instructions must match");
44     } else {
45       *pd_address_in_code() = x;
46     }
47   } else if (which == Assembler::narrow_oop_operand) {
48     address disp = Assembler::locate_operand(addr(), which);
49     // both compressed oops and compressed classes look the same
50     if (Universe::heap()->is_in_reserved((oop)x)) {
51     if (verify_only) {
52       guarantee(*(uint32_t*) disp == oopDesc::encode_heap_oop((oop)x), "instructions must match");
53     } else {
54       *(int32_t*) disp = oopDesc::encode_heap_oop((oop)x);
55     }
56   } else {
57       if (verify_only) {
58         guarantee(*(uint32_t*) disp == Klass::encode_klass((Klass*)x), "instructions must match");
59       } else {
60         *(int32_t*) disp = Klass::encode_klass((Klass*)x);
61       }
62     }
63   } else {
64     // Note:  Use runtime_call_type relocations for call32_operand.
65     address ip = addr();
66     address disp = Assembler::locate_operand(ip, which);
67     address next_ip = Assembler::locate_next_instruction(ip);
68     if (verify_only) {
69       guarantee(*(int32_t*) disp == (x - next_ip), "instructions must match");
70     } else {
71       *(int32_t*) disp = x - next_ip;
72     }
73   }
74 #else
75   if (verify_only) {
76     guarantee(*pd_address_in_code() == (x + o), "instructions must match");
77   } else {
78     *pd_address_in_code() = x + o;
79   }
80 #endif // AMD64
81 }
82 
83 
pd_call_destination(address orig_addr)84 address Relocation::pd_call_destination(address orig_addr) {
85   intptr_t adj = 0;
86   if (orig_addr != NULL) {
87     // We just moved this call instruction from orig_addr to addr().
88     // This means its target will appear to have grown by addr() - orig_addr.
89     adj = -( addr() - orig_addr );
90   }
91   NativeInstruction* ni = nativeInstruction_at(addr());
92   if (ni->is_call()) {
93     return nativeCall_at(addr())->destination() + adj;
94   } else if (ni->is_jump()) {
95     return nativeJump_at(addr())->jump_destination() + adj;
96   } else if (ni->is_cond_jump()) {
97     return nativeGeneralJump_at(addr())->jump_destination() + adj;
98   } else if (ni->is_mov_literal64()) {
99     return (address) ((NativeMovConstReg*)ni)->data();
100   } else {
101     ShouldNotReachHere();
102     return NULL;
103   }
104 }
105 
106 
pd_set_call_destination(address x)107 void Relocation::pd_set_call_destination(address x) {
108   NativeInstruction* ni = nativeInstruction_at(addr());
109   if (ni->is_call()) {
110     nativeCall_at(addr())->set_destination(x);
111   } else if (ni->is_jump()) {
112     NativeJump* nj = nativeJump_at(addr());
113 
114     // Unresolved jumps are recognized by a destination of -1
115     // However 64bit can't actually produce such an address
116     // and encodes a jump to self but jump_destination will
117     // return a -1 as the signal. We must not relocate this
118     // jmp or the ic code will not see it as unresolved.
119 
120     if (nj->jump_destination() == (address) -1) {
121       x = addr(); // jump to self
122     }
123     nj->set_jump_destination(x);
124   } else if (ni->is_cond_jump()) {
125     // %%%% kludge this, for now, until we get a jump_destination method
126     address old_dest = nativeGeneralJump_at(addr())->jump_destination();
127     address disp = Assembler::locate_operand(addr(), Assembler::call32_operand);
128     *(jint*)disp += (x - old_dest);
129   } else if (ni->is_mov_literal64()) {
130     ((NativeMovConstReg*)ni)->set_data((intptr_t)x);
131   } else {
132     ShouldNotReachHere();
133   }
134 }
135 
136 
pd_address_in_code()137 address* Relocation::pd_address_in_code() {
138   // All embedded Intel addresses are stored in 32-bit words.
139   // Since the addr points at the start of the instruction,
140   // we must parse the instruction a bit to find the embedded word.
141   assert(is_data(), "must be a DataRelocation");
142   typedef Assembler::WhichOperand WhichOperand;
143   WhichOperand which = (WhichOperand) format(); // that is, disp32 or imm/imm32
144 #ifdef AMD64
145   assert(which == Assembler::disp32_operand ||
146          which == Assembler::call32_operand ||
147          which == Assembler::imm_operand, "format unpacks ok");
148   // The "address" in the code is a displacement can't return it as
149   // and address* since it is really a jint*
150   guarantee(which == Assembler::imm_operand, "must be immediate operand");
151 #else
152   assert(which == Assembler::disp32_operand || which == Assembler::imm_operand, "format unpacks ok");
153 #endif // AMD64
154   return (address*) Assembler::locate_operand(addr(), which);
155 }
156 
157 
pd_get_address_from_code()158 address Relocation::pd_get_address_from_code() {
159 #ifdef AMD64
160   // All embedded Intel addresses are stored in 32-bit words.
161   // Since the addr points at the start of the instruction,
162   // we must parse the instruction a bit to find the embedded word.
163   assert(is_data(), "must be a DataRelocation");
164   typedef Assembler::WhichOperand WhichOperand;
165   WhichOperand which = (WhichOperand) format(); // that is, disp32 or imm/imm32
166   assert(which == Assembler::disp32_operand ||
167          which == Assembler::call32_operand ||
168          which == Assembler::imm_operand, "format unpacks ok");
169   if (which != Assembler::imm_operand) {
170     address ip = addr();
171     address disp = Assembler::locate_operand(ip, which);
172     address next_ip = Assembler::locate_next_instruction(ip);
173     address a = next_ip + *(int32_t*) disp;
174     return a;
175   }
176 #endif // AMD64
177   return *pd_address_in_code();
178 }
179 
fix_relocation_after_move(const CodeBuffer * src,CodeBuffer * dest)180 void poll_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
181 #ifdef _LP64
182   if (!Assembler::is_polling_page_far()) {
183     typedef Assembler::WhichOperand WhichOperand;
184     WhichOperand which = (WhichOperand) format();
185     // This format is imm but it is really disp32
186     which = Assembler::disp32_operand;
187     address orig_addr = old_addr_for(addr(), src, dest);
188     NativeInstruction* oni = nativeInstruction_at(orig_addr);
189     int32_t* orig_disp = (int32_t*) Assembler::locate_operand(orig_addr, which);
190     // This poll_addr is incorrect by the size of the instruction it is irrelevant
191     intptr_t poll_addr = (intptr_t)oni + *orig_disp;
192 
193     NativeInstruction* ni = nativeInstruction_at(addr());
194     intptr_t new_disp = poll_addr - (intptr_t) ni;
195 
196     int32_t* disp = (int32_t*) Assembler::locate_operand(addr(), which);
197     * disp = (int32_t)new_disp;
198   }
199 #endif // _LP64
200 }
201 
fix_relocation_after_move(const CodeBuffer * src,CodeBuffer * dest)202 void poll_return_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
203 #ifdef _LP64
204   if (!Assembler::is_polling_page_far()) {
205     typedef Assembler::WhichOperand WhichOperand;
206     WhichOperand which = (WhichOperand) format();
207     // This format is imm but it is really disp32
208     which = Assembler::disp32_operand;
209     address orig_addr = old_addr_for(addr(), src, dest);
210     NativeInstruction* oni = nativeInstruction_at(orig_addr);
211     int32_t* orig_disp = (int32_t*) Assembler::locate_operand(orig_addr, which);
212     // This poll_addr is incorrect by the size of the instruction it is irrelevant
213     intptr_t poll_addr = (intptr_t)oni + *orig_disp;
214 
215     NativeInstruction* ni = nativeInstruction_at(addr());
216     intptr_t new_disp = poll_addr - (intptr_t) ni;
217 
218     int32_t* disp = (int32_t*) Assembler::locate_operand(addr(), which);
219     * disp = (int32_t)new_disp;
220   }
221 #endif // _LP64
222 }
223 
pd_fix_value(address x)224 void metadata_Relocation::pd_fix_value(address x) {
225 }
226