src/cpu/aarch64/vm/macroAssembler_aarch64.cpp

rev 10278 : 8150394: aarch64: add support for 8.1 LSE CAS instructions
Reviewed-by: duke
Contributed-by: ananth.jasty@caviumnetworks.com, edward.nevill@gmail.com

*** 2069,2078 ****
--- 2069,2085 ----
                                  Label &succeed, Label *fail) {
    // oldv holds comparison value
    // newv holds value to write in exchange
    // addr identifies memory word to compare against/update
    // tmp returns 0/1 for success/failure
+   if (UseLSE) {
+     mov(tmp, oldv);
+     casal(oldv, newv, addr);
+     cmp(tmp, oldv);
+     br(Assembler::EQ, succeed);
+     membar(AnyAny);
+   } else {
      Label retry_load, nope;
  
      bind(retry_load);
      // flush and load exclusive from the memory location
      // and fail if it is not what we expect
*** 2087,2106 ****
--- 2094,2121 ----
      b(retry_load);
      // if the memory word differs we return it in oldv and signal a fail
      bind(nope);
      membar(AnyAny);
      mov(oldv, tmp);
+   }
    if (fail)
      b(*fail);
  }
  
  void MacroAssembler::cmpxchgw(Register oldv, Register newv, Register addr, Register tmp,
                                  Label &succeed, Label *fail) {
    // oldv holds comparison value
    // newv holds value to write in exchange
    // addr identifies memory word to compare against/update
    // tmp returns 0/1 for success/failure
+   if (UseLSE) {
+     mov(tmp, oldv);
+     casalw(oldv, newv, addr);
+     cmp(tmp, oldv);
+     br(Assembler::EQ, succeed);
+     membar(AnyAny);
+   } else {
      Label retry_load, nope;
  
      bind(retry_load);
      // flush and load exclusive from the memory location
      // and fail if it is not what we expect
*** 2115,2124 ****
--- 2130,2140 ----
      b(retry_load);
      // if the memory word differs we return it in oldv and signal a fail
      bind(nope);
      membar(AnyAny);
      mov(oldv, tmp);
+   }
    if (fail)
      b(*fail);
  }
  
  static bool different(Register a, RegisterOrConstant b, Register c) {