diff -r 9720ad0a40b6 -r 54b344d9dd4e src/hotspot/cpu/s390/vtableStubs_s390.cpp --- a/src/hotspot/cpu/s390/vtableStubs_s390.cpp Sat Sep 01 12:02:07 2018 -0700 +++ b/src/hotspot/cpu/s390/vtableStubs_s390.cpp Mon Sep 03 09:43:08 2018 +0200 @@ -1,6 +1,6 @@ /* - * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved. - * Copyright (c) 2016, 2017 SAP SE. All rights reserved. + * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2016, 2018 SAP SE. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it @@ -37,9 +37,6 @@ #include "opto/runtime.hpp" #endif -// Machine-dependent part of VtableStubs: create vtableStub of correct -// size and initialize its code. - #define __ masm-> #ifndef PRODUCT @@ -48,123 +45,140 @@ // Used by compiler only; may use only caller saved, non-argument registers. VtableStub* VtableStubs::create_vtable_stub(int vtable_index) { - - const int code_length = VtableStub::pd_code_size_limit(true); - VtableStub *s = new(code_length) VtableStub(true, vtable_index); - if (s == NULL) { // Indicates OOM In the code cache. + // Read "A word on VtableStub sizing" in share/code/vtableStubs.hpp for details on stub sizing. + const int stub_code_length = code_size_limit(true); + VtableStub* s = new(stub_code_length) VtableStub(true, vtable_index); + // Can be NULL if there is no free space in the code cache. + if (s == NULL) { return NULL; } + // Count unused bytes in instruction sequences of variable size. + // We add them to the computed buffer size in order to avoid + // overflow in subsequently generated stubs. + address start_pc; + int slop_bytes = 0; + int slop_delta = 0; + ResourceMark rm; - CodeBuffer cb(s->entry_point(), code_length); - MacroAssembler *masm = new MacroAssembler(&cb); - int padding_bytes = 0; + CodeBuffer cb(s->entry_point(), stub_code_length); + MacroAssembler* masm = new MacroAssembler(&cb); #if (!defined(PRODUCT) && defined(COMPILER2)) if (CountCompiledCalls) { - // Count unused bytes - // worst case actual size - padding_bytes += __ load_const_size() - __ load_const_optimized_rtn_len(Z_R1_scratch, (long)SharedRuntime::nof_megamorphic_calls_addr(), true); - + // worst case actual size + slop_delta = __ load_const_size() - __ load_const_optimized_rtn_len(Z_R1_scratch, (long)SharedRuntime::nof_megamorphic_calls_addr(), true); + slop_bytes += slop_delta; + assert(slop_delta >= 0, "negative slop(%d) encountered, adjust code size estimate!", slop_delta); // Use generic emitter for direct memory increment. // Abuse Z_method as scratch register for generic emitter. // It is loaded further down anyway before it is first used. + // No dynamic code size variance here, increment is 1, always. __ add2mem_32(Address(Z_R1_scratch), 1, Z_method); } #endif assert(VtableStub::receiver_location() == Z_R2->as_VMReg(), "receiver expected in Z_ARG1"); - // Get receiver klass. - // Must do an explicit check if implicit checks are disabled. - address npe_addr = __ pc(); // npe == NULL ptr exception + const Register rcvr_klass = Z_R1_scratch; + address npe_addr = __ pc(); // npe == NULL ptr exception + // check if we must do an explicit check (implicit checks disabled, offset too large). __ null_check(Z_ARG1, Z_R1_scratch, oopDesc::klass_offset_in_bytes()); - const Register rcvr_klass = Z_R1_scratch; + // Get receiver klass. __ load_klass(rcvr_klass, Z_ARG1); - // Set method (in case of interpreted method), and destination address. - int entry_offset = in_bytes(Klass::vtable_start_offset()) + - vtable_index * vtableEntry::size_in_bytes(); - #ifndef PRODUCT if (DebugVtables) { - Label L; + NearLabel L; // Check offset vs vtable length. const Register vtable_idx = Z_R0_scratch; - // Count unused bytes. - // worst case actual size - padding_bytes += __ load_const_size() - __ load_const_optimized_rtn_len(vtable_idx, vtable_index*vtableEntry::size_in_bytes(), true); + // worst case actual size + slop_delta = __ load_const_size() - __ load_const_optimized_rtn_len(vtable_idx, vtable_index*vtableEntry::size(), true); + slop_bytes += slop_delta; + assert(slop_delta >= 0, "negative slop(%d) encountered, adjust code size estimate!", slop_delta); - assert(Immediate::is_uimm12(in_bytes(Klass::vtable_length_offset())), "disp to large"); + assert(Displacement::is_shortDisp(in_bytes(Klass::vtable_length_offset())), "disp to large"); __ z_cl(vtable_idx, in_bytes(Klass::vtable_length_offset()), rcvr_klass); __ z_brl(L); __ z_lghi(Z_ARG3, vtable_index); // Debug code, don't optimize. __ call_VM(noreg, CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), Z_ARG1, Z_ARG3, false); // Count unused bytes (assume worst case here). - padding_bytes += 12; + slop_bytes += 12; __ bind(L); } #endif - int v_off = entry_offset + vtableEntry::method_offset_in_bytes(); + int entry_offset = in_bytes(Klass::vtable_start_offset()) + + vtable_index * vtableEntry::size_in_bytes(); + int v_off = entry_offset + vtableEntry::method_offset_in_bytes(); + // Set method (in case of interpreted method), and destination address. // Duplicate safety code from enc_class Java_Dynamic_Call_dynTOC. if (Displacement::is_validDisp(v_off)) { __ z_lg(Z_method/*method oop*/, v_off, rcvr_klass/*class oop*/); // Account for the load_const in the else path. - padding_bytes += __ load_const_size(); + slop_delta = __ load_const_size(); } else { // Worse case, offset does not fit in displacement field. - __ load_const(Z_method, v_off); // Z_method temporarily holds the offset value. + // worst case actual size + slop_delta = __ load_const_size() - __ load_const_optimized_rtn_len(Z_method, v_off, true); __ z_lg(Z_method/*method oop*/, 0, Z_method/*method offset*/, rcvr_klass/*class oop*/); } + slop_bytes += slop_delta; #ifndef PRODUCT if (DebugVtables) { - Label L; + NearLabel L; __ z_ltgr(Z_method, Z_method); __ z_brne(L); - __ stop("Vtable entry is ZERO",102); + __ stop("Vtable entry is ZERO", 102); __ bind(L); } #endif - address ame_addr = __ pc(); // ame = abstract method error - - // Must do an explicit check if implicit checks are disabled. + // Must do an explicit check if offset too large or implicit checks are disabled. + address ame_addr = __ pc(); __ null_check(Z_method, Z_R1_scratch, in_bytes(Method::from_compiled_offset())); __ z_lg(Z_R1_scratch, in_bytes(Method::from_compiled_offset()), Z_method); __ z_br(Z_R1_scratch); masm->flush(); - - s->set_exception_points(npe_addr, ame_addr); + bookkeeping(masm, tty, s, npe_addr, ame_addr, true, vtable_index, slop_bytes, 0); return s; } VtableStub* VtableStubs::create_itable_stub(int itable_index) { - const int code_length = VtableStub::pd_code_size_limit(false); - VtableStub *s = new(code_length) VtableStub(false, itable_index); - if (s == NULL) { // Indicates OOM in the code cache. + // Read "A word on VtableStub sizing" in share/code/vtableStubs.hpp for details on stub sizing. + const int stub_code_length = code_size_limit(false); + VtableStub* s = new(stub_code_length) VtableStub(false, itable_index); + // Can be NULL if there is no free space in the code cache. + if (s == NULL) { return NULL; } + // Count unused bytes in instruction sequences of variable size. + // We add them to the computed buffer size in order to avoid + // overflow in subsequently generated stubs. + address start_pc; + int slop_bytes = 0; + int slop_delta = 0; ResourceMark rm; - CodeBuffer cb(s->entry_point(), code_length); - MacroAssembler *masm = new MacroAssembler(&cb); - int padding_bytes = 0; + CodeBuffer cb(s->entry_point(), stub_code_length); + MacroAssembler* masm = new MacroAssembler(&cb); #if (!defined(PRODUCT) && defined(COMPILER2)) if (CountCompiledCalls) { - // Count unused bytes - // worst case actual size - padding_bytes += __ load_const_size() - __ load_const_optimized_rtn_len(Z_R1_scratch, (long)SharedRuntime::nof_megamorphic_calls_addr(), true); - + // worst case actual size + slop_delta = __ load_const_size() - __ load_const_optimized_rtn_len(Z_R1_scratch, (long)SharedRuntime::nof_megamorphic_calls_addr(), true); + slop_bytes += slop_delta; + assert(slop_delta >= 0, "negative slop(%d) encountered, adjust code size estimate!", slop_delta); // Use generic emitter for direct memory increment. - // Use Z_tmp_1 as scratch register for generic emitter. - __ add2mem_32((Z_R1_scratch), 1, Z_tmp_1); + // Abuse Z_method as scratch register for generic emitter. + // It is loaded further down anyway before it is first used. + // No dynamic code size variance here, increment is 1, always. + __ add2mem_32(Address(Z_R1_scratch), 1, Z_method); } #endif @@ -178,7 +192,7 @@ interface = Z_tmp_2; // Get receiver klass. - // Must do an explicit check if implicit checks are disabled. + // Must do an explicit check if offset too large or implicit checks are disabled. address npe_addr = __ pc(); // npe == NULL ptr exception __ null_check(Z_ARG1, Z_R1_scratch, oopDesc::klass_offset_in_bytes()); __ load_klass(rcvr_klass, Z_ARG1); @@ -195,10 +209,10 @@ #ifndef PRODUCT if (DebugVtables) { - Label ok1; + NearLabel ok1; __ z_ltgr(Z_method, Z_method); __ z_brne(ok1); - __ stop("method is null",103); + __ stop("method is null", 103); __ bind(ok1); } #endif @@ -213,39 +227,24 @@ // Handle IncompatibleClassChangeError in itable stubs. __ bind(no_such_interface); - // Count unused bytes - // worst case actual size - // We force resolving of the call site by jumping to - // the "handle wrong method" stub, and so let the + // more detailed IncompatibleClassChangeError + // we force re-resolving of the call site by jumping to + // the "handle wrong method" stub, thus letting the // interpreter runtime do all the dirty work. - padding_bytes += __ load_const_size() - __ load_const_optimized_rtn_len(Z_R1_scratch, (long)SharedRuntime::get_handle_wrong_method_stub(), true); + // worst case actual size + slop_delta = __ load_const_size() - __ load_const_optimized_rtn_len(Z_R1_scratch, (long)SharedRuntime::get_handle_wrong_method_stub(), true); + slop_bytes += slop_delta; + assert(slop_delta >= 0, "negative slop(%d) encountered, adjust code size estimate!", slop_delta); __ z_br(Z_R1_scratch); masm->flush(); + bookkeeping(masm, tty, s, npe_addr, ame_addr, false, itable_index, slop_bytes, 0); - s->set_exception_points(npe_addr, ame_addr); return s; } -// In order to tune these parameters, run the JVM with VM options -// +PrintMiscellaneous and +WizardMode to see information about -// actual itable stubs. Run it with -Xmx31G -XX:+UseCompressedOops. -int VtableStub::pd_code_size_limit(bool is_vtable_stub) { - int size = DebugVtables ? 216 : 0; - if (CountCompiledCalls) { - size += 6 * 4; - } - size += is_vtable_stub ? 36 : 140; - if (UseCompressedClassPointers) { - size += MacroAssembler::instr_size_for_decode_klass_not_null(); - } - if (!ImplicitNullChecks) { - size += 36; - } - return size; -} - int VtableStub::pd_code_alignment() { + // System z cache line size is 256 bytes, but octoword-alignment is quite ok. const unsigned int icache_line_size = 32; return icache_line_size; }