1.1 --- a/src/cpu/x86/vm/macroAssembler_x86.cpp Thu Nov 05 11:42:42 2015 +0100
1.2 +++ b/src/cpu/x86/vm/macroAssembler_x86.cpp Tue May 07 20:38:26 2019 +0000
1.3 @@ -4119,6 +4119,42 @@
1.4 }
1.5 }
1.6
1.7 +void MacroAssembler::resolve_jobject(Register value,
1.8 + Register thread,
1.9 + Register tmp) {
1.10 + assert_different_registers(value, thread, tmp);
1.11 + Label done, not_weak;
1.12 + testptr(value, value);
1.13 + jcc(Assembler::zero, done); // Use NULL as-is.
1.14 + testptr(value, JNIHandles::weak_tag_mask); // Test for jweak tag.
1.15 + jcc(Assembler::zero, not_weak);
1.16 + // Resolve jweak.
1.17 + movptr(value, Address(value, -JNIHandles::weak_tag_value));
1.18 + verify_oop(value);
1.19 +#if INCLUDE_ALL_GCS
1.20 + if (UseG1GC) {
1.21 + g1_write_barrier_pre(noreg /* obj */,
1.22 + value /* pre_val */,
1.23 + thread /* thread */,
1.24 + tmp /* tmp */,
1.25 + true /* tosca_live */,
1.26 + true /* expand_call */);
1.27 + }
1.28 +#endif // INCLUDE_ALL_GCS
1.29 + jmp(done);
1.30 + bind(not_weak);
1.31 + // Resolve (untagged) jobject.
1.32 + movptr(value, Address(value, 0));
1.33 + verify_oop(value);
1.34 + bind(done);
1.35 +}
1.36 +
1.37 +void MacroAssembler::clear_jweak_tag(Register possibly_jweak) {
1.38 + const int32_t inverted_jweak_mask = ~static_cast<int32_t>(JNIHandles::weak_tag_mask);
1.39 + STATIC_ASSERT(inverted_jweak_mask == -2); // otherwise check this code
1.40 + // The inverted mask is sign-extended
1.41 + andptr(possibly_jweak, inverted_jweak_mask);
1.42 +}
1.43
1.44 //////////////////////////////////////////////////////////////////////////////////
1.45 #if INCLUDE_ALL_GCS
