40 // Since hashCode is usually polymorphic at call sites we can't do this
41 // optimization at the call site without a lot of work.
42 void SharedRuntime::inline_check_hashcode_from_object_header(MacroAssembler* masm,
43 const methodHandle& method,
44 Register obj_reg,
45 Register result) {
46 Label slowCase;
47
48 // Unlike for Object.hashCode, System.identityHashCode is static method and
49 // gets object as argument instead of the receiver.
50 if (method->intrinsic_id() == vmIntrinsics::_identityHashCode) {
51 Label Continue;
52 // return 0 for null reference input
53 __ cmpptr(obj_reg, NULL_WORD);
54 __ jcc(Assembler::notEqual, Continue);
55 __ xorptr(result, result);
56 __ ret(0);
57 __ bind(Continue);
58 }
59
60 __ movptr(result, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
61
62
63 if (LockingMode == LM_LIGHTWEIGHT) {
64 if (!UseObjectMonitorTable) {
65 // check if monitor
66 __ testptr(result, markWord::monitor_value);
67 __ jcc(Assembler::notZero, slowCase);
68 }
69 } else {
70 // check if locked
71 __ testptr(result, markWord::unlocked_value);
72 __ jcc(Assembler::zero, slowCase);
73 }
74
75 // get hash
76 // Read the header and build a mask to get its hash field.
77 // Depend on hash_mask being at most 32 bits and avoid the use of hash_mask_in_place
78 // because it could be larger than 32 bits in a 64-bit vm. See markWord.hpp.
79 __ shrptr(result, markWord::hash_shift);
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40 // Since hashCode is usually polymorphic at call sites we can't do this
41 // optimization at the call site without a lot of work.
42 void SharedRuntime::inline_check_hashcode_from_object_header(MacroAssembler* masm,
43 const methodHandle& method,
44 Register obj_reg,
45 Register result) {
46 Label slowCase;
47
48 // Unlike for Object.hashCode, System.identityHashCode is static method and
49 // gets object as argument instead of the receiver.
50 if (method->intrinsic_id() == vmIntrinsics::_identityHashCode) {
51 Label Continue;
52 // return 0 for null reference input
53 __ cmpptr(obj_reg, NULL_WORD);
54 __ jcc(Assembler::notEqual, Continue);
55 __ xorptr(result, result);
56 __ ret(0);
57 __ bind(Continue);
58 }
59
60 if (UseCompactObjectHeaders) {
61 // Don't generate anything else and always take the slow-path for now.
62 return;
63 }
64
65 __ movptr(result, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
66
67
68 if (LockingMode == LM_LIGHTWEIGHT) {
69 if (!UseObjectMonitorTable) {
70 // check if monitor
71 __ testptr(result, markWord::monitor_value);
72 __ jcc(Assembler::notZero, slowCase);
73 }
74 } else {
75 // check if locked
76 __ testptr(result, markWord::unlocked_value);
77 __ jcc(Assembler::zero, slowCase);
78 }
79
80 // get hash
81 // Read the header and build a mask to get its hash field.
82 // Depend on hash_mask being at most 32 bits and avoid the use of hash_mask_in_place
83 // because it could be larger than 32 bits in a 64-bit vm. See markWord.hpp.
84 __ shrptr(result, markWord::hash_shift);
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