jdk8-mips64-public/hotspot: src/cpu/x86/vm/c1_MacroAssembler

src/cpu/x86/vm/c1_MacroAssembler_x86.cpp@ba764ed4b6f2 (annotated)

src/cpu/x86/vm/c1_MacroAssembler_x86.cpp

Sun, 13 Apr 2008 17:43:42 -0400

author: coleenp
date: Sun, 13 Apr 2008 17:43:42 -0400
changeset 548: ba764ed4b6f2
parent 435: a61af66fc99e
child 631: d1605aabd0a1
permissions: -rw-r--r--

6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
Summary: Compressed oops in instances, arrays, and headers. Code contributors are coleenp, phh, never, swamyv
Reviewed-by: jmasa, kamg, acorn, tbell, kvn, rasbold

 /*
  * Copyright 1999-2007 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

Mercurial > jdk8-mips64-public > hotspot / annotate

src/cpu/x86/vm/c1_MacroAssembler_x86.cpp@ba764ed4b6f2 (annotated)

src/cpu/x86/vm/c1_MacroAssembler_x86.cpp