src/hotspot/cpu/aarch64/gc/shared/barrierSetAssembler_aarch64.cpp

rev 50637 : [mq]: JDK-8205336.patch
rev 50638 : [mq]: JDK-8205336-01.patch

*** 22,32 ****
--- 22,34 ----
   *
   */
  
  #include "precompiled.hpp"
  #include "gc/shared/barrierSetAssembler.hpp"
+ #include "gc/shared/collectedHeap.hpp"
  #include "runtime/jniHandles.hpp"
+ #include "runtime/thread.hpp"
  
  #define __ masm->
  
  void BarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
                                    Register dst, Address src, Register tmp1, Register tmp_thread) {
*** 119,123 ****
--- 121,231 ----
    // If mask changes we need to ensure that the inverse is still encodable as an immediate
    STATIC_ASSERT(JNIHandles::weak_tag_mask == 1);
    __ andr(obj, obj, ~JNIHandles::weak_tag_mask);
    __ ldr(obj, Address(obj, 0));             // *obj
  }
+ 
+ // Defines obj, preserves var_size_in_bytes, okay for t2 == var_size_in_bytes.
+ void BarrierSetAssembler::tlab_allocate(MacroAssembler* masm, Register obj,
+                                         Register var_size_in_bytes,
+                                         int con_size_in_bytes,
+                                         Register t1,
+                                         Register t2,
+                                         Label& slow_case) {
+   assert_different_registers(obj, t2);
+   assert_different_registers(obj, var_size_in_bytes);
+   Register end = t2;
+ 
+   // verify_tlab();
+ 
+   __ ldr(obj, Address(rthread, JavaThread::tlab_top_offset()));
+   if (var_size_in_bytes == noreg) {
+     __ lea(end, Address(obj, con_size_in_bytes));
+   } else {
+     __ lea(end, Address(obj, var_size_in_bytes));
+   }
+   __ ldr(rscratch1, Address(rthread, JavaThread::tlab_end_offset()));
+   __ cmp(end, rscratch1);
+   __ br(Assembler::HI, slow_case);
+ 
+   // update the tlab top pointer
+   __ str(end, Address(rthread, JavaThread::tlab_top_offset()));
+ 
+   // recover var_size_in_bytes if necessary
+   if (var_size_in_bytes == end) {
+     __ sub(var_size_in_bytes, var_size_in_bytes, obj);
+   }
+   // verify_tlab();
+ }
+ 
+ // Defines obj, preserves var_size_in_bytes
+ void BarrierSetAssembler::eden_allocate(MacroAssembler* masm, Register obj,
+                                         Register var_size_in_bytes,
+                                         int con_size_in_bytes,
+                                         Register t1,
+                                         Label& slow_case) {
+   assert_different_registers(obj, var_size_in_bytes, t1);
+   if (!Universe::heap()->supports_inline_contig_alloc()) {
+     __ b(slow_case);
+   } else {
+     Register end = t1;
+     Register heap_end = rscratch2;
+     Label retry;
+     __ bind(retry);
+     {
+       unsigned long offset;
+       __ adrp(rscratch1, ExternalAddress((address) Universe::heap()->end_addr()), offset);
+       __ ldr(heap_end, Address(rscratch1, offset));
+     }
+ 
+     ExternalAddress heap_top((address) Universe::heap()->top_addr());
+ 
+     // Get the current top of the heap
+     {
+       unsigned long offset;
+       __ adrp(rscratch1, heap_top, offset);
+       // Use add() here after ARDP, rather than lea().
+       // lea() does not generate anything if its offset is zero.
+       // However, relocs expect to find either an ADD or a load/store
+       // insn after an ADRP.  add() always generates an ADD insn, even
+       // for add(Rn, Rn, 0).
+       __ add(rscratch1, rscratch1, offset);
+       __ ldaxr(obj, rscratch1);
+     }
+ 
+     // Adjust it my the size of our new object
+     if (var_size_in_bytes == noreg) {
+       __ lea(end, Address(obj, con_size_in_bytes));
+     } else {
+       __ lea(end, Address(obj, var_size_in_bytes));
+     }
+ 
+     // if end < obj then we wrapped around high memory
+     __ cmp(end, obj);
+     __ br(Assembler::LO, slow_case);
+ 
+     __ cmp(end, heap_end);
+     __ br(Assembler::HI, slow_case);
+ 
+     // If heap_top hasn't been changed by some other thread, update it.
+     __ stlxr(rscratch2, end, rscratch1);
+     __ cbnzw(rscratch2, retry);
+ 
+     incr_allocated_bytes(masm, var_size_in_bytes, con_size_in_bytes, t1);
+   }
+ }
+ 
+ void BarrierSetAssembler::incr_allocated_bytes(MacroAssembler* masm,
+                                                Register var_size_in_bytes,
+                                                int con_size_in_bytes,
+                                                Register t1) {
+   assert(t1->is_valid(), "need temp reg");
+ 
+   __ ldr(t1, Address(rthread, in_bytes(JavaThread::allocated_bytes_offset())));
+   if (var_size_in_bytes->is_valid()) {
+     __ add(t1, t1, var_size_in_bytes);
+   } else {
+     __ add(t1, t1, con_size_in_bytes);
+   }
+   __ str(t1, Address(rthread, in_bytes(JavaThread::allocated_bytes_offset())));
+ }
+