src/hotspot/cpu/x86/jniFastGetField_x86_64.cpp

*** 75,90 ****
    ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr());
    __ mov32 (rcounter, counter);
    __ mov   (robj, c_rarg1);
    __ testb (rcounter, 1);
    __ jcc (Assembler::notZero, slow);
!   if (os::is_MP()) {
      __ xorptr(robj, rcounter);
      __ xorptr(robj, rcounter);                   // obj, since
                                                  // robj ^ rcounter ^ rcounter == robj
                                                  // robj is data dependent on rcounter.
-   }
  
    __ mov   (roffset, c_rarg2);
    __ shrptr(roffset, 2);                         // offset
  
    // Both robj and rtmp are clobbered by try_resolve_jobject_in_native.
--- 75,89 ----
    ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr());
    __ mov32 (rcounter, counter);
    __ mov   (robj, c_rarg1);
    __ testb (rcounter, 1);
    __ jcc (Assembler::notZero, slow);
! 
    __ xorptr(robj, rcounter);
    __ xorptr(robj, rcounter);  // obj, since
                                // robj ^ rcounter ^ rcounter == robj
                                // robj is data dependent on rcounter.
  
    __ mov   (roffset, c_rarg2);
    __ shrptr(roffset, 2);                         // offset
  
    // Both robj and rtmp are clobbered by try_resolve_jobject_in_native.
*** 102,120 ****
      case T_INT:     __ movl   (rax, Address(robj, roffset, Address::times_1)); break;
      case T_LONG:    __ movq   (rax, Address(robj, roffset, Address::times_1)); break;
      default:        ShouldNotReachHere();
    }
  
!   if (os::is_MP()) {
      __ lea(rcounter_addr, counter);
-     // ca is data dependent on rax.
      __ xorptr(rcounter_addr, rax);
      __ xorptr(rcounter_addr, rax);
      __ cmpl (rcounter, Address(rcounter_addr, 0));
!   } else {
!     __ cmp32 (rcounter, counter);
!   }
    __ jcc (Assembler::notEqual, slow);
  
    __ ret (0);
  
    slowcase_entry_pclist[count++] = __ pc();
--- 101,116 ----
      case T_INT:     __ movl   (rax, Address(robj, roffset, Address::times_1)); break;
      case T_LONG:    __ movq   (rax, Address(robj, roffset, Address::times_1)); break;
      default:        ShouldNotReachHere();
    }
  
!   // create data dependency on rax
    __ lea(rcounter_addr, counter);
    __ xorptr(rcounter_addr, rax);
    __ xorptr(rcounter_addr, rax);
    __ cmpl (rcounter, Address(rcounter_addr, 0));
! 
    __ jcc (Assembler::notEqual, slow);
  
    __ ret (0);
  
    slowcase_entry_pclist[count++] = __ pc();
*** 179,194 ****
    ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr());
    __ mov32 (rcounter, counter);
    __ mov   (robj, c_rarg1);
    __ testb (rcounter, 1);
    __ jcc (Assembler::notZero, slow);
!   if (os::is_MP()) {
      __ xorptr(robj, rcounter);
      __ xorptr(robj, rcounter);                   // obj, since
                                                  // robj ^ rcounter ^ rcounter == robj
                                                  // robj is data dependent on rcounter.
-   }
  
    // Both robj and rtmp are clobbered by try_resolve_jobject_in_native.
    BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
    bs->try_resolve_jobject_in_native(masm, /* jni_env */ c_rarg0, robj, rtmp, slow);
    DEBUG_ONLY(__ movl(rtmp, 0xDEADC0DE);)
--- 175,189 ----
    ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr());
    __ mov32 (rcounter, counter);
    __ mov   (robj, c_rarg1);
    __ testb (rcounter, 1);
    __ jcc (Assembler::notZero, slow);
! 
    __ xorptr(robj, rcounter);
    __ xorptr(robj, rcounter);  // obj, since
                                // robj ^ rcounter ^ rcounter == robj
                                // robj is data dependent on rcounter.
  
    // Both robj and rtmp are clobbered by try_resolve_jobject_in_native.
    BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
    bs->try_resolve_jobject_in_native(masm, /* jni_env */ c_rarg0, robj, rtmp, slow);
    DEBUG_ONLY(__ movl(rtmp, 0xDEADC0DE);)
*** 202,221 ****
      case T_FLOAT:  __ movflt (xmm0, Address(robj, roffset, Address::times_1)); break;
      case T_DOUBLE: __ movdbl (xmm0, Address(robj, roffset, Address::times_1)); break;
      default:        ShouldNotReachHere();
    }
  
-   if (os::is_MP()) {
      __ lea(rcounter_addr, counter);
      __ movdq (rax, xmm0);
      // counter address is data dependent on xmm0.
      __ xorptr(rcounter_addr, rax);
      __ xorptr(rcounter_addr, rax);
      __ cmpl (rcounter, Address(rcounter_addr, 0));
-   } else {
-     __ cmp32 (rcounter, counter);
-   }
    __ jcc (Assembler::notEqual, slow);
  
    __ ret (0);
  
    slowcase_entry_pclist[count++] = __ pc();
--- 197,212 ----