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  *
15  * You should have received a copy of the GNU General Public License version
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17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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24 
25 #ifndef CPU_ARM_VM_MACROASSEMBLER_ARM_INLINE_HPP
26 #define CPU_ARM_VM_MACROASSEMBLER_ARM_INLINE_HPP
27 
28 #include "asm/assembler.inline.hpp"
29 #include "asm/codeBuffer.hpp"
30 #include "code/codeCache.hpp"
31 #include "runtime/handles.inline.hpp"
32 
pd_patch_instruction(address branch,address target,const char * file,int line)33 inline void MacroAssembler::pd_patch_instruction(address branch, address target, const char* file, int line) {
34   int instr = *(int*)branch;
35   int new_offset = (int)(target - branch - 8);
36   assert((new_offset & 3) == 0, "bad alignment");
37 
38   if ((instr & 0x0e000000) == 0x0a000000) {
39     // B or BL instruction
40     assert(new_offset < 0x2000000 && new_offset > -0x2000000, "encoding constraint");
41     *(int*)branch = (instr & 0xff000000) | ((unsigned int)new_offset << 6 >> 8);
42   } else if((unsigned int)instr == address_placeholder_instruction) {
43     // address
44     *(int*)branch = (int)target;
45   } else if ((instr & 0x0fff0000) == 0x028f0000 || ((instr & 0x0fff0000) == 0x024f0000)) {
46     // ADR
47     int encoding = 0x8 << 20; // ADD
48     if (new_offset < 0) {
49       encoding = 0x4 << 20; // SUB
50       new_offset = -new_offset;
51     }
52     AsmOperand o(new_offset);
53     *(int*)branch = (instr & 0xff0ff000) | encoding | o.encoding();
54   } else {
55     // LDR Rd, [PC, offset] instruction
56     assert((instr & 0x0f7f0000) == 0x051f0000, "Must be ldr_literal");
57     assert(new_offset < 4096 && new_offset > -4096, "encoding constraint");
58     if (new_offset >= 0) {
59       *(int*)branch = (instr & 0xff0ff000) | 9 << 20 | new_offset;
60     } else {
61       *(int*)branch = (instr & 0xff0ff000) | 1 << 20 | -new_offset;
62     }
63   }
64 }
65 
66 #endif // CPU_ARM_VM_MACROASSEMBLER_ARM_INLINE_HPP
67