src/cpu/sparc/vm/assembler_sparc.cpp

*** 4674,4678 ****
--- 4674,4725 ----
      // call indirectly to solve generation ordering problem
      AddressLiteral base(Universe::narrow_oop_base_addr());
      load_ptr_contents(base, G6_heapbase);
    }
  }
+ 
+ // Compare char[] arrays aligned to 4 bytes.
+ void MacroAssembler::char_arrays_equals(Register ary1, Register ary2,
+                                         Register limit, Register result,
+                                         Register chr1, Register chr2, Label& Ldone) {
+   Label Lvector, Lloop;
+   assert(chr1 == result, "should be the same");
+ 
+   // Note: limit contains number of bytes (2*char_elements) != 0.
+   andcc(limit, 0x2, chr1); // trailing character ?
+   br(Assembler::zero, false, Assembler::pt, Lvector);
+   delayed()->nop();
+ 
+   // compare the trailing char
+   sub(limit, sizeof(jchar), limit);
+   lduh(ary1, limit, chr1);
+   lduh(ary2, limit, chr2);
+   cmp(chr1, chr2);
+   br(Assembler::notEqual, true, Assembler::pt, Ldone);
+   delayed()->mov(G0, result);     // not equal
+ 
+   // only one char ?
+   br_on_reg_cond(rc_z, true, Assembler::pn, limit, Ldone);
+   delayed()->add(G0, 1, result); // zero-length arrays are equal
+ 
+   // word by word compare, dont't need alignment check
+   bind(Lvector);
+   // Shift ary1 and ary2 to the end of the arrays, negate limit
+   add(ary1, limit, ary1);
+   add(ary2, limit, ary2);
+   neg(limit, limit);
+ 
+   lduw(ary1, limit, chr1);
+   bind(Lloop);
+   lduw(ary2, limit, chr2);
+   cmp(chr1, chr2);
+   br(Assembler::notEqual, true, Assembler::pt, Ldone);
+   delayed()->mov(G0, result);     // not equal
+   inccc(limit, 2*sizeof(jchar));
+   // annul LDUW if branch is not taken to prevent access past end of array
+   br(Assembler::notZero, true, Assembler::pt, Lloop);
+   delayed()->lduw(ary1, limit, chr1); // hoisted
+ 
+   // Caller should set it:
+   // add(G0, 1, result); // equals
+ }
+