| /* |
| * Copyright 1999-2008 Sun Microsystems, 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| * CA 95054 USA or visit www.sun.com if you need additional information or |
| * have any questions. |
| * |
| */ |
| |
| #include "incls/_precompiled.incl" |
| #include "incls/_c1_MacroAssembler_x86.cpp.incl" |
| |
| int C1_MacroAssembler::lock_object(Register hdr, Register obj, Register disp_hdr, Register scratch, Label& slow_case) { |
| const int aligned_mask = 3; |
| const int hdr_offset = oopDesc::mark_offset_in_bytes(); |
| assert(hdr == rax, "hdr must be rax, for the cmpxchg instruction"); |
| assert(hdr != obj && hdr != disp_hdr && obj != disp_hdr, "registers must be different"); |
| assert(BytesPerWord == 4, "adjust aligned_mask and code"); |
| Label done; |
| int null_check_offset = -1; |
| |
| verify_oop(obj); |
| |
| // save object being locked into the BasicObjectLock |
| movl(Address(disp_hdr, BasicObjectLock::obj_offset_in_bytes()), obj); |
| |
| 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 |
| movl(hdr, Address(obj, hdr_offset)); |
| // and mark it as unlocked |
| orl(hdr, markOopDesc::unlocked_value); |
| // save unlocked object header into the displaced header location on the stack |
| movl(Address(disp_hdr, 0), hdr); |
| // 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 |
| if (os::is_MP()) MacroAssembler::lock(); // must be immediately before cmpxchg! |
| cmpxchg(disp_hdr, Address(obj, hdr_offset)); |
| // if the object header was the same, we're done |
| if (PrintBiasedLockingStatistics) { |
| cond_inc32(Assembler::equal, |
| ExternalAddress((address)BiasedLocking::fast_path_entry_count_addr())); |
| } |
| jcc(Assembler::equal, 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) rsp <= hdr |
| // 3) hdr <= rsp + page_size |
| // |
| // these 3 tests can be done by evaluating the following expression: |
| // |
| // (hdr - rsp) & (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 |
| subl(hdr, rsp); |
| andl(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) |
| movl(Address(disp_hdr, 0), hdr); |
| // otherwise we don't care about the result and handle locking via runtime call |
| jcc(Assembler::notZero, slow_case); |
| // done |
| bind(done); |
| return null_check_offset; |
| } |
| |
| |
| void C1_MacroAssembler::unlock_object(Register hdr, Register obj, Register disp_hdr, Label& slow_case) { |
| const int aligned_mask = 3; |
| const int hdr_offset = oopDesc::mark_offset_in_bytes(); |
| assert(disp_hdr == rax, "disp_hdr must be rax, for the cmpxchg instruction"); |
| assert(hdr != obj && hdr != disp_hdr && obj != disp_hdr, "registers must be different"); |
| assert(BytesPerWord == 4, "adjust aligned_mask and code"); |
| Label done; |
| |
| if (UseBiasedLocking) { |
| // load object |
| movl(obj, Address(disp_hdr, BasicObjectLock::obj_offset_in_bytes())); |
| biased_locking_exit(obj, hdr, done); |
| } |
| |
| // load displaced header |
| movl(hdr, Address(disp_hdr, 0)); |
| // if the loaded hdr is NULL we had recursive locking |
| testl(hdr, hdr); |
| // if we had recursive locking, we are done |
| jcc(Assembler::zero, done); |
| if (!UseBiasedLocking) { |
| // load object |
| movl(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 (os::is_MP()) MacroAssembler::lock(); // must be immediately before cmpxchg! |
| cmpxchg(hdr, Address(obj, hdr_offset)); |
| // if the object header was not pointing to the displaced header, |
| // we do unlocking via runtime call |
| jcc(Assembler::notEqual, 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); |
| } |
| } |
| |
| |
| 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); |
| movl(t1, Address(klass, Klass::prototype_header_offset_in_bytes() + klassOopDesc::klass_part_offset_in_bytes())); |
| movl(Address(obj, oopDesc::mark_offset_in_bytes()), t1); |
| } else { |
| movl(Address(obj, oopDesc::mark_offset_in_bytes ()), (int)markOopDesc::prototype()); |
| } |
| |
| movl(Address(obj, oopDesc::klass_offset_in_bytes()), klass); |
| if (len->is_valid()) { |
| movl(Address(obj, arrayOopDesc::length_offset_in_bytes()), len); |
| } |
| } |
| |
| |
| // preserves obj, destroys len_in_bytes |
| void C1_MacroAssembler::initialize_body(Register obj, Register len_in_bytes, int hdr_size_in_bytes, Register t1) { |
| Label done; |
| assert(obj != len_in_bytes && obj != t1 && t1 != len_in_bytes, "registers must be different"); |
| assert((hdr_size_in_bytes & (BytesPerWord - 1)) == 0, "header size is not a multiple of BytesPerWord"); |
| Register index = len_in_bytes; |
| subl(index, hdr_size_in_bytes); |
| jcc(Assembler::zero, done); |
| // initialize topmost word, divide index by 2, check if odd and test if zero |
| // note: for the remaining code to work, index must be a multiple of BytesPerWord |
| #ifdef ASSERT |
| { Label L; |
| testl(index, BytesPerWord - 1); |
| jcc(Assembler::zero, L); |
| stop("index is not a multiple of BytesPerWord"); |
| bind(L); |
| } |
| #endif |
| xorl(t1, t1); // use _zero reg to clear memory (shorter code) |
| if (UseIncDec) { |
| shrl(index, 3); // divide by 8 and set carry flag if bit 2 was set |
| } else { |
| shrl(index, 2); // use 2 instructions to avoid partial flag stall |
| shrl(index, 1); |
| } |
| // index could have been not a multiple of 8 (i.e., bit 2 was set) |
| { Label even; |
| // note: if index was a multiple of 8, than it cannot |
| // be 0 now otherwise it must have been 0 before |
| // => if it is even, we don't need to check for 0 again |
| jcc(Assembler::carryClear, even); |
| // clear topmost word (no jump needed if conditional assignment would work here) |
| movl(Address(obj, index, Address::times_8, hdr_size_in_bytes - 0*BytesPerWord), t1); |
| // index could be 0 now, need to check again |
| jcc(Assembler::zero, done); |
| bind(even); |
| } |
| // initialize remaining object fields: rdx is a multiple of 2 now |
| { Label loop; |
| bind(loop); |
| movl(Address(obj, index, Address::times_8, hdr_size_in_bytes - 1*BytesPerWord), t1); |
| movl(Address(obj, index, Address::times_8, hdr_size_in_bytes - 2*BytesPerWord), t1); |
| decrement(index); |
| jcc(Assembler::notZero, loop); |
| } |
| |
| // done |
| 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(obj == rax, "obj must be in rax, for cmpxchg"); |
| assert(obj != t1 && obj != t2 && t1 != t2, "registers must be different"); // 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); |
| } |
| |
| void C1_MacroAssembler::initialize_object(Register obj, Register klass, Register var_size_in_bytes, int con_size_in_bytes, Register t1, Register t2) { |
| assert((con_size_in_bytes & MinObjAlignmentInBytesMask) == 0, |
| "con_size_in_bytes is not multiple of alignment"); |
| const int hdr_size_in_bytes = instanceOopDesc::base_offset_in_bytes(); |
| |
| initialize_header(obj, klass, noreg, t1, t2); |
| |
| // clear rest of allocated space |
| const Register t1_zero = t1; |
| const Register index = t2; |
| const int threshold = 6 * BytesPerWord; // approximate break even point for code size (see comments below) |
| if (var_size_in_bytes != noreg) { |
| movl(index, var_size_in_bytes); |
| initialize_body(obj, index, hdr_size_in_bytes, t1_zero); |
| } else if (con_size_in_bytes <= threshold) { |
| // use explicit null stores |
| // code size = 2 + 3*n bytes (n = number of fields to clear) |
| xorl(t1_zero, t1_zero); // use t1_zero reg to clear memory (shorter code) |
| for (int i = hdr_size_in_bytes; i < con_size_in_bytes; i += BytesPerWord) |
| movl(Address(obj, i), t1_zero); |
| } else if (con_size_in_bytes > hdr_size_in_bytes) { |
| // use loop to null out the fields |
| // code size = 16 bytes for even n (n = number of fields to clear) |
| // initialize last object field first if odd number of fields |
| xorl(t1_zero, t1_zero); // use t1_zero reg to clear memory (shorter code) |
| movl(index, (con_size_in_bytes - hdr_size_in_bytes) >> 3); |
| // initialize last object field if constant size is odd |
| if (((con_size_in_bytes - hdr_size_in_bytes) & 4) != 0) |
| movl(Address(obj, con_size_in_bytes - (1*BytesPerWord)), t1_zero); |
| // initialize remaining object fields: rdx is a multiple of 2 |
| { Label loop; |
| bind(loop); |
| movl(Address(obj, index, Address::times_8, |
| hdr_size_in_bytes - (1*BytesPerWord)), t1_zero); |
| movl(Address(obj, index, Address::times_8, |
| hdr_size_in_bytes - (2*BytesPerWord)), t1_zero); |
| decrement(index); |
| jcc(Assembler::notZero, loop); |
| } |
| } |
| |
| if (DTraceAllocProbes) { |
| assert(obj == rax, "must be"); |
| 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, Address::ScaleFactor f, Register klass, Label& slow_case) { |
| assert(obj == rax, "obj must be in rax, for cmpxchg"); |
| assert_different_registers(obj, len, t1, t2, klass); |
| |
| // determine alignment mask |
| assert(BytesPerWord == 4, "must be a multiple of 2 for masking code to work"); |
| |
| // check for negative or excessive length |
| cmpl(len, max_array_allocation_length); |
| jcc(Assembler::above, slow_case); |
| |
| const Register arr_size = t2; // okay to be the same |
| // align object end |
| movl(arr_size, header_size * BytesPerWord + MinObjAlignmentInBytesMask); |
| leal(arr_size, Address(arr_size, len, f)); |
| andl(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); |
| |
| if (DTraceAllocProbes) { |
| assert(obj == rax, "must be"); |
| 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"); |
| int start_offset = offset(); |
| cmpl(iCache, Address(receiver, oopDesc::klass_offset_in_bytes())); |
| // if icache check fails, then jump to runtime routine |
| // Note: RECEIVER must still contain the receiver! |
| jump_cc(Assembler::notEqual, |
| RuntimeAddress(SharedRuntime::get_ic_miss_stub())); |
| assert(offset() - start_offset == 9, "check alignment in emit_method_entry"); |
| } |
| |
| |
| void C1_MacroAssembler::method_exit(bool restore_frame) { |
| if (restore_frame) { |
| leave(); |
| } |
| ret(0); |
| } |
| |
| |
| void C1_MacroAssembler::build_frame(int frame_size_in_bytes) { |
| // Make sure there is enough stack space for this method's activation. |
| // Note that we do this before doing an enter(). This matches the |
| // ordering of C2's stack overflow check / rsp decrement and allows |
| // the SharedRuntime stack overflow handling to be consistent |
| // between the two compilers. |
| generate_stack_overflow_check(frame_size_in_bytes); |
| |
| enter(); |
| #ifdef TIERED |
| // c2 leaves fpu stack dirty. Clean it on entry |
| if (UseSSE < 2 ) { |
| empty_FPU_stack(); |
| } |
| #endif // TIERED |
| decrement(rsp, frame_size_in_bytes); // does not emit code for frame_size == 0 |
| } |
| |
| |
| void C1_MacroAssembler::unverified_entry(Register receiver, Register ic_klass) { |
| if (C1Breakpoint) int3(); |
| inline_cache_check(receiver, ic_klass); |
| } |
| |
| |
| void C1_MacroAssembler::verified_entry() { |
| if (C1Breakpoint)int3(); |
| // build frame |
| verify_FPU(0, "method_entry"); |
| } |
| |
| |
| #ifndef PRODUCT |
| |
| void C1_MacroAssembler::verify_stack_oop(int stack_offset) { |
| if (!VerifyOops) return; |
| verify_oop_addr(Address(rsp, stack_offset)); |
| } |
| |
| void C1_MacroAssembler::verify_not_null_oop(Register r) { |
| if (!VerifyOops) return; |
| Label not_null; |
| testl(r, r); |
| jcc(Assembler::notZero, not_null); |
| stop("non-null oop required"); |
| bind(not_null); |
| verify_oop(r); |
| } |
| |
| void C1_MacroAssembler::invalidate_registers(bool inv_rax, bool inv_rbx, bool inv_rcx, bool inv_rdx, bool inv_rsi, bool inv_rdi) { |
| #ifdef ASSERT |
| if (inv_rax) movl(rax, 0xDEAD); |
| if (inv_rbx) movl(rbx, 0xDEAD); |
| if (inv_rcx) movl(rcx, 0xDEAD); |
| if (inv_rdx) movl(rdx, 0xDEAD); |
| if (inv_rsi) movl(rsi, 0xDEAD); |
| if (inv_rdi) movl(rdi, 0xDEAD); |
| #endif |
| } |
| |
| #endif // ifndef PRODUCT |