*** old/src/cpu/x86/vm/x86_64.ad	Wed Dec  7 12:03:22 2011
--- new/src/cpu/x86/vm/x86_64.ad	Wed Dec  7 12:03:22 2011

*** 12160,12175 ****
--- 12160,12175 ----
  %{
    match(Set result (PartialSubtypeCheck sub super));
    effect(KILL rcx, KILL cr);
  
    ins_cost(1100);  // slightly larger than the next version
!   format %{ "movq    rdi, [$sub + (sizeof(oopDesc) + Klass::secondary_supers_offset_in_bytes())]\n\t"
              "movl    rcx, [rdi + arrayOopDesc::length_offset_in_bytes()]\t# length to scan\n\t"
              "addq    rdi, arrayOopDex::base_offset_in_bytes(T_OBJECT)\t# Skip to start of data; set NZ in case count is zero\n\t"
              "repne   scasq\t# Scan *rdi++ for a match with rax while rcx--\n\t"
              "jne,s   miss\t\t# Missed: rdi not-zero\n\t"
!             "movq    [$sub + (sizeof(oopDesc) + Klass::secondary_super_cache_offset_in_bytes())], $super\t# Hit: update cache\n\t"
              "xorq    $result, $result\t\t Hit: rdi zero\n\t"
      "miss:\t" %}
  
    opcode(0x1); // Force a XOR of RDI
    ins_encode(enc_PartialSubtypeCheck());

*** 12183,12198 ****
--- 12183,12198 ----
  %{
    match(Set cr (CmpP (PartialSubtypeCheck sub super) zero));
    effect(KILL rcx, KILL result);
  
    ins_cost(1000);
!   format %{ "movq    rdi, [$sub + (sizeof(oopDesc) + Klass::secondary_supers_offset_in_bytes())]\n\t"
              "movl    rcx, [rdi + arrayOopDesc::length_offset_in_bytes()]\t# length to scan\n\t"
              "addq    rdi, arrayOopDex::base_offset_in_bytes(T_OBJECT)\t# Skip to start of data; set NZ in case count is zero\n\t"
              "repne   scasq\t# Scan *rdi++ for a match with rax while cx-- != 0\n\t"
              "jne,s   miss\t\t# Missed: flags nz\n\t"
!             "movq    [$sub + (sizeof(oopDesc) + Klass::secondary_super_cache_offset_in_bytes())], $super\t# Hit: update cache\n\t"
      "miss:\t" %}
  
    opcode(0x0); // No need to XOR RDI
    ins_encode(enc_PartialSubtypeCheck());
    ins_pipe(pipe_slow);