1 /*
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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/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 
pd_set_data_value(address x,intptr_t o,bool verify_only)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 
pd_call_destination(address orig_addr)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 
pd_set_call_destination(address x)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 
pd_address_in_code()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 
pd_get_address_from_code()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 
fix_relocation_after_move(const CodeBuffer * src,CodeBuffer * dest)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 
pd_fix_value(address x)208 void metadata_Relocation::pd_fix_value(address x) {
209 }
210