| /* |
| * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved. |
| * Copyright (c) 2014, Red Hat Inc. 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 |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "c1/c1_MacroAssembler.hpp" |
| #include "c1/c1_Runtime1.hpp" |
| #include "classfile/systemDictionary.hpp" |
| #include "gc/shared/collectedHeap.hpp" |
| #include "interpreter/interpreter.hpp" |
| #include "oops/arrayOop.hpp" |
| #include "oops/markOop.hpp" |
| #include "runtime/basicLock.hpp" |
| #include "runtime/biasedLocking.hpp" |
| #include "runtime/os.hpp" |
| #include "runtime/sharedRuntime.hpp" |
| #include "runtime/stubRoutines.hpp" |
| |
| void C1_MacroAssembler::float_cmp(bool is_float, int unordered_result, |
| FloatRegister f0, FloatRegister f1, |
| Register result) |
| { |
| Label done; |
| if (is_float) { |
| fcmps(f0, f1); |
| } else { |
| fcmpd(f0, f1); |
| } |
| if (unordered_result < 0) { |
| // we want -1 for unordered or less than, 0 for equal and 1 for |
| // greater than. |
| cset(result, NE); // Not equal or unordered |
| cneg(result, result, LT); // Less than or unordered |
| } else { |
| // we want -1 for less than, 0 for equal and 1 for unordered or |
| // greater than. |
| cset(result, NE); // Not equal or unordered |
| cneg(result, result, LO); // Less than |
| } |
| } |
| |
| int C1_MacroAssembler::lock_object(Register hdr, Register obj, Register disp_hdr, Register scratch, Label& slow_case) { |
| const int aligned_mask = BytesPerWord -1; |
| const int hdr_offset = oopDesc::mark_offset_in_bytes(); |
| assert(hdr != obj && hdr != disp_hdr && obj != disp_hdr, "registers must be different"); |
| Label done, fail; |
| int null_check_offset = -1; |
| |
| verify_oop(obj); |
| |
| // save object being locked into the BasicObjectLock |
| str(obj, Address(disp_hdr, BasicObjectLock::obj_offset_in_bytes())); |
| |
| if (UseBiasedLocking) { |
| assert(scratch != noreg, "should have scratch register at this point"); |
| null_check_offset = biased_locking_enter(disp_hdr, obj, hdr, scratch, false, done, &slow_case); |
| } else { |
| null_check_offset = offset(); |
| } |
| |
| // Load object header |
| ldr(hdr, Address(obj, hdr_offset)); |
| // and mark it as unlocked |
| orr(hdr, hdr, markOopDesc::unlocked_value); |
| // save unlocked object header into the displaced header location on the stack |
| str(hdr, Address(disp_hdr, 0)); |
| // test if object header is still the same (i.e. unlocked), and if so, store the |
| // displaced header address in the object header - if it is not the same, get the |
| // object header instead |
| lea(rscratch2, Address(obj, hdr_offset)); |
| cmpxchgptr(hdr, disp_hdr, rscratch2, rscratch1, done, /*fallthough*/NULL); |
| // if the object header was the same, we're done |
| // if the object header was not the same, it is now in the hdr register |
| // => test if it is a stack pointer into the same stack (recursive locking), i.e.: |
| // |
| // 1) (hdr & aligned_mask) == 0 |
| // 2) sp <= hdr |
| // 3) hdr <= sp + page_size |
| // |
| // these 3 tests can be done by evaluating the following expression: |
| // |
| // (hdr - sp) & (aligned_mask - page_size) |
| // |
| // assuming both the stack pointer and page_size have their least |
| // significant 2 bits cleared and page_size is a power of 2 |
| mov(rscratch1, sp); |
| sub(hdr, hdr, rscratch1); |
| ands(hdr, hdr, aligned_mask - os::vm_page_size()); |
| // for recursive locking, the result is zero => save it in the displaced header |
| // location (NULL in the displaced hdr location indicates recursive locking) |
| str(hdr, Address(disp_hdr, 0)); |
| // otherwise we don't care about the result and handle locking via runtime call |
| cbnz(hdr, slow_case); |
| // done |
| bind(done); |
| if (PrintBiasedLockingStatistics) { |
| lea(rscratch2, ExternalAddress((address)BiasedLocking::fast_path_entry_count_addr())); |
| addmw(Address(rscratch2, 0), 1, rscratch1); |
| } |
| return null_check_offset; |
| } |
| |
| |
| void C1_MacroAssembler::unlock_object(Register hdr, Register obj, Register disp_hdr, Label& slow_case) { |
| const int aligned_mask = BytesPerWord -1; |
| const int hdr_offset = oopDesc::mark_offset_in_bytes(); |
| assert(hdr != obj && hdr != disp_hdr && obj != disp_hdr, "registers must be different"); |
| Label done; |
| |
| if (UseBiasedLocking) { |
| // load object |
| ldr(obj, Address(disp_hdr, BasicObjectLock::obj_offset_in_bytes())); |
| biased_locking_exit(obj, hdr, done); |
| } |
| |
| // load displaced header |
| ldr(hdr, Address(disp_hdr, 0)); |
| // if the loaded hdr is NULL we had recursive locking |
| // if we had recursive locking, we are done |
| cbz(hdr, done); |
| if (!UseBiasedLocking) { |
| // load object |
| ldr(obj, Address(disp_hdr, BasicObjectLock::obj_offset_in_bytes())); |
| } |
| verify_oop(obj); |
| // test if object header is pointing to the displaced header, and if so, restore |
| // the displaced header in the object - if the object header is not pointing to |
| // the displaced header, get the object header instead |
| // if the object header was not pointing to the displaced header, |
| // we do unlocking via runtime call |
| if (hdr_offset) { |
| lea(rscratch1, Address(obj, hdr_offset)); |
| cmpxchgptr(disp_hdr, hdr, rscratch1, rscratch2, done, &slow_case); |
| } else { |
| cmpxchgptr(disp_hdr, hdr, obj, rscratch2, done, &slow_case); |
| } |
| // done |
| bind(done); |
| } |
| |
| |
| // Defines obj, preserves var_size_in_bytes |
| void C1_MacroAssembler::try_allocate(Register obj, Register var_size_in_bytes, int con_size_in_bytes, Register t1, Register t2, Label& slow_case) { |
| if (UseTLAB) { |
| tlab_allocate(obj, var_size_in_bytes, con_size_in_bytes, t1, t2, slow_case); |
| } else { |
| eden_allocate(obj, var_size_in_bytes, con_size_in_bytes, t1, slow_case); |
| incr_allocated_bytes(noreg, var_size_in_bytes, con_size_in_bytes, t1); |
| } |
| } |
| |
| void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register t1, Register t2) { |
| assert_different_registers(obj, klass, len); |
| if (UseBiasedLocking && !len->is_valid()) { |
| assert_different_registers(obj, klass, len, t1, t2); |
| ldr(t1, Address(klass, Klass::prototype_header_offset())); |
| } else { |
| // This assumes that all prototype bits fit in an int32_t |
| mov(t1, (int32_t)(intptr_t)markOopDesc::prototype()); |
| } |
| str(t1, Address(obj, oopDesc::mark_offset_in_bytes())); |
| |
| if (UseCompressedClassPointers) { // Take care not to kill klass |
| encode_klass_not_null(t1, klass); |
| strw(t1, Address(obj, oopDesc::klass_offset_in_bytes())); |
| } else { |
| str(klass, Address(obj, oopDesc::klass_offset_in_bytes())); |
| } |
| |
| if (len->is_valid()) { |
| strw(len, Address(obj, arrayOopDesc::length_offset_in_bytes())); |
| } else if (UseCompressedClassPointers) { |
| store_klass_gap(obj, zr); |
| } |
| } |
| |
| // preserves obj, destroys len_in_bytes |
| void C1_MacroAssembler::initialize_body(Register obj, Register len_in_bytes, int hdr_size_in_bytes, Register t1) { |
| assert(hdr_size_in_bytes >= 0, "header size must be positive or 0"); |
| Label done; |
| |
| // len_in_bytes is positive and ptr sized |
| subs(len_in_bytes, len_in_bytes, hdr_size_in_bytes); |
| br(Assembler::EQ, done); |
| |
| // Preserve obj |
| if (hdr_size_in_bytes) |
| add(obj, obj, hdr_size_in_bytes); |
| zero_memory(obj, len_in_bytes, t1); |
| if (hdr_size_in_bytes) |
| sub(obj, obj, hdr_size_in_bytes); |
| |
| bind(done); |
| } |
| |
| |
| void C1_MacroAssembler::allocate_object(Register obj, Register t1, Register t2, int header_size, int object_size, Register klass, Label& slow_case) { |
| assert_different_registers(obj, t1, t2); // XXX really? |
| assert(header_size >= 0 && object_size >= header_size, "illegal sizes"); |
| |
| try_allocate(obj, noreg, object_size * BytesPerWord, t1, t2, slow_case); |
| |
| initialize_object(obj, klass, noreg, object_size * HeapWordSize, t1, t2, UseTLAB); |
| } |
| |
| void C1_MacroAssembler::initialize_object(Register obj, Register klass, Register var_size_in_bytes, int con_size_in_bytes, Register t1, Register t2, bool is_tlab_allocated) { |
| assert((con_size_in_bytes & MinObjAlignmentInBytesMask) == 0, |
| "con_size_in_bytes is not multiple of alignment"); |
| const int hdr_size_in_bytes = instanceOopDesc::header_size() * HeapWordSize; |
| |
| initialize_header(obj, klass, noreg, t1, t2); |
| |
| if (!(UseTLAB && ZeroTLAB && is_tlab_allocated)) { |
| // clear rest of allocated space |
| const Register index = t2; |
| const int threshold = 16 * BytesPerWord; // approximate break even point for code size (see comments below) |
| if (var_size_in_bytes != noreg) { |
| mov(index, var_size_in_bytes); |
| initialize_body(obj, index, hdr_size_in_bytes, t1); |
| } else if (con_size_in_bytes <= threshold) { |
| // use explicit null stores |
| int i = hdr_size_in_bytes; |
| if (i < con_size_in_bytes && (con_size_in_bytes % (2 * BytesPerWord))) { |
| str(zr, Address(obj, i)); |
| i += BytesPerWord; |
| } |
| for (; i < con_size_in_bytes; i += 2 * BytesPerWord) |
| stp(zr, zr, Address(obj, i)); |
| } else if (con_size_in_bytes > hdr_size_in_bytes) { |
| block_comment("zero memory"); |
| // use loop to null out the fields |
| |
| int words = (con_size_in_bytes - hdr_size_in_bytes) / BytesPerWord; |
| mov(index, words / 8); |
| |
| const int unroll = 8; // Number of str(zr) instructions we'll unroll |
| int remainder = words % unroll; |
| lea(rscratch1, Address(obj, hdr_size_in_bytes + remainder * BytesPerWord)); |
| |
| Label entry_point, loop; |
| b(entry_point); |
| |
| bind(loop); |
| sub(index, index, 1); |
| for (int i = -unroll; i < 0; i++) { |
| if (-i == remainder) |
| bind(entry_point); |
| str(zr, Address(rscratch1, i * wordSize)); |
| } |
| if (remainder == 0) |
| bind(entry_point); |
| add(rscratch1, rscratch1, unroll * wordSize); |
| cbnz(index, loop); |
| |
| } |
| } |
| |
| membar(StoreStore); |
| |
| if (CURRENT_ENV->dtrace_alloc_probes()) { |
| assert(obj == r0, "must be"); |
| far_call(RuntimeAddress(Runtime1::entry_for(Runtime1::dtrace_object_alloc_id))); |
| } |
| |
| verify_oop(obj); |
| } |
| void C1_MacroAssembler::allocate_array(Register obj, Register len, Register t1, Register t2, int header_size, int f, Register klass, Label& slow_case) { |
| assert_different_registers(obj, len, t1, t2, klass); |
| |
| // determine alignment mask |
| assert(!(BytesPerWord & 1), "must be a multiple of 2 for masking code to work"); |
| |
| // check for negative or excessive length |
| mov(rscratch1, (int32_t)max_array_allocation_length); |
| cmp(len, rscratch1); |
| br(Assembler::HS, slow_case); |
| |
| const Register arr_size = t2; // okay to be the same |
| // align object end |
| mov(arr_size, (int32_t)header_size * BytesPerWord + MinObjAlignmentInBytesMask); |
| add(arr_size, arr_size, len, ext::uxtw, f); |
| andr(arr_size, arr_size, ~MinObjAlignmentInBytesMask); |
| |
| try_allocate(obj, arr_size, 0, t1, t2, slow_case); |
| |
| initialize_header(obj, klass, len, t1, t2); |
| |
| // clear rest of allocated space |
| const Register len_zero = len; |
| initialize_body(obj, arr_size, header_size * BytesPerWord, len_zero); |
| |
| membar(StoreStore); |
| |
| if (CURRENT_ENV->dtrace_alloc_probes()) { |
| assert(obj == r0, "must be"); |
| far_call(RuntimeAddress(Runtime1::entry_for(Runtime1::dtrace_object_alloc_id))); |
| } |
| |
| verify_oop(obj); |
| } |
| |
| |
| void C1_MacroAssembler::inline_cache_check(Register receiver, Register iCache) { |
| verify_oop(receiver); |
| // explicit NULL check not needed since load from [klass_offset] causes a trap |
| // check against inline cache |
| assert(!MacroAssembler::needs_explicit_null_check(oopDesc::klass_offset_in_bytes()), "must add explicit null check"); |
| |
| cmp_klass(receiver, iCache, rscratch1); |
| } |
| |
| |
| void C1_MacroAssembler::build_frame(int framesize, int bang_size_in_bytes) { |
| // If we have to make this method not-entrant we'll overwrite its |
| // first instruction with a jump. For this action to be legal we |
| // must ensure that this first instruction is a B, BL, NOP, BKPT, |
| // SVC, HVC, or SMC. Make it a NOP. |
| nop(); |
| assert(bang_size_in_bytes >= framesize, "stack bang size incorrect"); |
| // Make sure there is enough stack space for this method's activation. |
| // Note that we do this before doing an enter(). |
| generate_stack_overflow_check(bang_size_in_bytes); |
| MacroAssembler::build_frame(framesize + 2 * wordSize); |
| if (NotifySimulator) { |
| notify(Assembler::method_entry); |
| } |
| } |
| |
| void C1_MacroAssembler::remove_frame(int framesize) { |
| MacroAssembler::remove_frame(framesize + 2 * wordSize); |
| if (NotifySimulator) { |
| notify(Assembler::method_reentry); |
| } |
| } |
| |
| |
| void C1_MacroAssembler::verified_entry() { |
| } |
| |
| #ifndef PRODUCT |
| |
| void C1_MacroAssembler::verify_stack_oop(int stack_offset) { |
| if (!VerifyOops) return; |
| verify_oop_addr(Address(sp, stack_offset), "oop"); |
| } |
| |
| void C1_MacroAssembler::verify_not_null_oop(Register r) { |
| if (!VerifyOops) return; |
| Label not_null; |
| cbnz(r, not_null); |
| stop("non-null oop required"); |
| bind(not_null); |
| verify_oop(r); |
| } |
| |
| void C1_MacroAssembler::invalidate_registers(bool inv_r0, bool inv_r19, bool inv_r2, bool inv_r3, bool inv_r4, bool inv_r5) { |
| #ifdef ASSERT |
| static int nn; |
| if (inv_r0) mov(r0, 0xDEAD); |
| if (inv_r19) mov(r19, 0xDEAD); |
| if (inv_r2) mov(r2, nn++); |
| if (inv_r3) mov(r3, 0xDEAD); |
| if (inv_r4) mov(r4, 0xDEAD); |
| if (inv_r5) mov(r5, 0xDEAD); |
| #endif |
| } |
| #endif // ifndef PRODUCT |