src/cpu/x86/vm/templateInterpreter_x86_64.cpp

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rev 2161 : [mq]: initial-intrinsification-changes
rev 2162 : [mq]: code-review-comments-vladimir

*** 755,764 **** --- 755,853 ---- } return entry_point; } + // Method entry for java.lang.ref.Reference.get. + address InterpreterGenerator::generate_Reference_get_entry(void) { + #ifndef SERIALGC + // Code: _aload_0, _getfield, _areturn + // parameter size = 1 + // + // The code that gets generated by this routine is split into 2 parts: + // 1. The "intrinsified" code for G1 (or any SATB based GC), + // 2. The slow path - which is an expansion of the regular method entry. + // + // Notes:- + // * In the G1 code we do not check whether we need to block for + // a safepoint. If G1 is enabled then we must execute the specialized + // code for Reference.get (except when the Reference object is null) + // so that we can log the value in the referent field with an SATB + // update buffer. + // If the code for the getfield template is modified so that the + // G1 pre-barrier code is executed when the current method is + // Reference.get() then going through the normal method entry + // will be fine. + // * The G1 code can, however, check the receiver object (the instance + // of java.lang.Reference) and jump to the slow path if null. If the + // Reference object is null then we obviously cannot fetch the referent + // and so we don't need to call the G1 pre-barrier. Thus we can use the + // regular method entry code to generate the NPE. + // + // This code is based on generate_accessor_enty. + // + // rbx: methodOop + + // r13: senderSP must preserve for slow path, set SP to it on fast path + + address entry = __ pc(); + + const int referent_offset = java_lang_ref_Reference::referent_offset; + guarantee(referent_offset > 0, "referent offset not initialized"); + + if (UseG1GC) { + Label slow_path; + // rbx: method + + // Check if local 0 != NULL + // If the receiver is null then it is OK to jump to the slow path. + __ movptr(rax, Address(rsp, wordSize)); + + __ testptr(rax, rax); + __ jcc(Assembler::zero, slow_path); + + // rax: local 0 + // rbx: method (but can be used as scratch now) + // rdx: scratch + // rdi: scratch + + // Generate the G1 pre-barrier code to log the value of + // the referent field in an SATB buffer. + + // Load the value of the referent field. + const Address field_address(rax, referent_offset); + __ load_heap_oop(rax, field_address); + + // Generate the G1 pre-barrier code to log the value of + // the referent field in an SATB buffer. + __ g1_write_barrier_pre(noreg /* obj */, + rax /* pre_val */, + r15_thread /* thread */, + rbx /* tmp */, + true /* tosca_live */, + true /* expand_call */); + + // _areturn + __ pop(rdi); // get return address + __ mov(rsp, r13); // set sp to sender sp + __ jmp(rdi); + __ ret(0); + + // generate a vanilla interpreter entry as the slow path + __ bind(slow_path); + (void) generate_normal_entry(false); + + return entry; + } + #endif // SERIALGC + + // If G1 is not enabled then attempt to go through the accessor entry point + // Reference.get is an accessor + return generate_accessor_entry(); + } + + // Interpreter stub for calling a native method. (asm interpreter) // This sets up a somewhat different looking stack for calling the // native method than the typical interpreter frame setup. address InterpreterGenerator::generate_native_entry(bool synchronized) { // determine code generation flags
*** 1461,1470 **** --- 1550,1561 ---- case Interpreter::java_lang_math_tan : // fall thru case Interpreter::java_lang_math_abs : // fall thru case Interpreter::java_lang_math_log : // fall thru case Interpreter::java_lang_math_log10 : // fall thru case Interpreter::java_lang_math_sqrt : entry_point = ((InterpreterGenerator*) this)->generate_math_entry(kind); break; + case Interpreter::java_lang_ref_reference_get + : entry_point = ((InterpreterGenerator*)this)->generate_Reference_get_entry(); break; default : ShouldNotReachHere(); break; } if (entry_point) { return entry_point;