1.1 --- a/src/cpu/x86/vm/stubGenerator_x86_32.cpp Wed Mar 18 11:37:48 2009 -0400
1.2 +++ b/src/cpu/x86/vm/stubGenerator_x86_32.cpp Thu Mar 19 09:13:24 2009 -0700
1.3 @@ -1310,81 +1310,51 @@
1.4 Address& super_check_offset_addr,
1.5 Address& super_klass_addr,
1.6 Register temp,
1.7 - Label* L_success_ptr, Label* L_failure_ptr) {
1.8 + Label* L_success, Label* L_failure) {
1.9 BLOCK_COMMENT("type_check:");
1.10
1.11 Label L_fallthrough;
1.12 - bool fall_through_on_success = (L_success_ptr == NULL);
1.13 - if (fall_through_on_success) {
1.14 - L_success_ptr = &L_fallthrough;
1.15 - } else {
1.16 - L_failure_ptr = &L_fallthrough;
1.17 - }
1.18 - Label& L_success = *L_success_ptr;
1.19 - Label& L_failure = *L_failure_ptr;
1.20 +#define LOCAL_JCC(assembler_con, label_ptr) \
1.21 + if (label_ptr != NULL) __ jcc(assembler_con, *(label_ptr)); \
1.22 + else __ jcc(assembler_con, L_fallthrough) /*omit semi*/
1.23
1.24 + // The following is a strange variation of the fast path which requires
1.25 + // one less register, because needed values are on the argument stack.
1.26 + // __ check_klass_subtype_fast_path(sub_klass, *super_klass*, temp,
1.27 + // L_success, L_failure, NULL);
1.28 assert_different_registers(sub_klass, temp);
1.29
1.30 - // a couple of useful fields in sub_klass:
1.31 - int ss_offset = (klassOopDesc::header_size() * HeapWordSize +
1.32 - Klass::secondary_supers_offset_in_bytes());
1.33 int sc_offset = (klassOopDesc::header_size() * HeapWordSize +
1.34 Klass::secondary_super_cache_offset_in_bytes());
1.35 - Address secondary_supers_addr(sub_klass, ss_offset);
1.36 - Address super_cache_addr( sub_klass, sc_offset);
1.37
1.38 // if the pointers are equal, we are done (e.g., String[] elements)
1.39 __ cmpptr(sub_klass, super_klass_addr);
1.40 - __ jcc(Assembler::equal, L_success);
1.41 + LOCAL_JCC(Assembler::equal, L_success);
1.42
1.43 // check the supertype display:
1.44 __ movl2ptr(temp, super_check_offset_addr);
1.45 Address super_check_addr(sub_klass, temp, Address::times_1, 0);
1.46 __ movptr(temp, super_check_addr); // load displayed supertype
1.47 __ cmpptr(temp, super_klass_addr); // test the super type
1.48 - __ jcc(Assembler::equal, L_success);
1.49 + LOCAL_JCC(Assembler::equal, L_success);
1.50
1.51 // if it was a primary super, we can just fail immediately
1.52 __ cmpl(super_check_offset_addr, sc_offset);
1.53 - __ jcc(Assembler::notEqual, L_failure);
1.54 + LOCAL_JCC(Assembler::notEqual, L_failure);
1.55
1.56 - // Now do a linear scan of the secondary super-klass chain.
1.57 - // This code is rarely used, so simplicity is a virtue here.
1.58 - inc_counter_np(SharedRuntime::_partial_subtype_ctr);
1.59 - {
1.60 - // The repne_scan instruction uses fixed registers, which we must spill.
1.61 - // (We need a couple more temps in any case.)
1.62 - __ push(rax);
1.63 - __ push(rcx);
1.64 - __ push(rdi);
1.65 - assert_different_registers(sub_klass, rax, rcx, rdi);
1.66 + // The repne_scan instruction uses fixed registers, which will get spilled.
1.67 + // We happen to know this works best when super_klass is in rax.
1.68 + Register super_klass = temp;
1.69 + __ movptr(super_klass, super_klass_addr);
1.70 + __ check_klass_subtype_slow_path(sub_klass, super_klass, noreg, noreg,
1.71 + L_success, L_failure);
1.72
1.73 - __ movptr(rdi, secondary_supers_addr);
1.74 - // Load the array length.
1.75 - __ movl(rcx, Address(rdi, arrayOopDesc::length_offset_in_bytes()));
1.76 - // Skip to start of data.
1.77 - __ addptr(rdi, arrayOopDesc::base_offset_in_bytes(T_OBJECT));
1.78 - // Scan rcx words at [edi] for occurance of rax,
1.79 - // Set NZ/Z based on last compare
1.80 - __ movptr(rax, super_klass_addr);
1.81 - __ repne_scan();
1.82 + __ bind(L_fallthrough);
1.83
1.84 - // Unspill the temp. registers:
1.85 - __ pop(rdi);
1.86 - __ pop(rcx);
1.87 - __ pop(rax);
1.88 - }
1.89 - __ jcc(Assembler::notEqual, L_failure);
1.90 + if (L_success == NULL) { BLOCK_COMMENT("L_success:"); }
1.91 + if (L_failure == NULL) { BLOCK_COMMENT("L_failure:"); }
1.92
1.93 - // Success. Cache the super we found and proceed in triumph.
1.94 - __ movptr(temp, super_klass_addr); // note: rax, is dead
1.95 - __ movptr(super_cache_addr, temp);
1.96 -
1.97 - if (!fall_through_on_success)
1.98 - __ jmp(L_success);
1.99 -
1.100 - // Fall through on failure!
1.101 - __ bind(L_fallthrough);
1.102 +#undef LOCAL_JCC
1.103 }
1.104
1.105 //
