--- /dev/null	2021-01-19 17:38:25.908523431 +0000
+++ new/src/cpu/aarch64/vm/c1_MacroAssembler_aarch64.cpp	2021-01-25 19:31:33.778445383 +0000
@@ -0,0 +1,453 @@
+/*
+ * Copyright (c) 2013, Red Hat Inc.
+ * Copyright (c) 1999, 2011, Oracle and/or its affiliates.
+ * 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_interface/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/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);
+  }
+}
+
+// Zero words; len is in bytes
+// Destroys all registers except addr
+// len must be a nonzero multiple of wordSize
+void C1_MacroAssembler::zero_memory(Register addr, Register len, Register t1) {
+  assert_different_registers(addr, len, t1, rscratch1, rscratch2);
+
+#ifdef ASSERT
+  { Label L;
+    tst(len, BytesPerWord - 1);
+    br(Assembler::EQ, L);
+    stop("len is not a multiple of BytesPerWord");
+    bind(L);
+  }
+#endif
+
+#ifndef PRODUCT
+  block_comment("zero memory");
+#endif
+
+  Label loop;
+  Label entry;
+
+//  Algorithm:
+//
+//    scratch1 = cnt & 7;
+//    cnt -= scratch1;
+//    p += scratch1;
+//    switch (scratch1) {
+//      do {
+//        cnt -= 8;
+//          p[-8] = 0;
+//        case 7:
+//          p[-7] = 0;
+//        case 6:
+//          p[-6] = 0;
+//          // ...
+//        case 1:
+//          p[-1] = 0;
+//        case 0:
+//          p += 8;
+//      } while (cnt);
+//    }
+
+  const int unroll = 8; // Number of str(zr) instructions we'll unroll
+
+  lsr(len, len, LogBytesPerWord);
+  andr(rscratch1, len, unroll - 1);  // tmp1 = cnt % unroll
+  sub(len, len, rscratch1);      // cnt -= unroll
+  // t1 always points to the end of the region we're about to zero
+  add(t1, addr, rscratch1, Assembler::LSL, LogBytesPerWord);
+  adr(rscratch2, entry);
+  sub(rscratch2, rscratch2, rscratch1, Assembler::LSL, 2);
+  br(rscratch2);
+  bind(loop);
+  sub(len, len, unroll);
+  for (int i = -unroll; i < 0; i++)
+    str(zr, Address(t1, i * wordSize));
+  bind(entry);
+  add(t1, t1, unroll * wordSize);
+  cbnz(len, loop);
+}
+
+// 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;
+  // index is positive and ptr sized
+  subs(index, index, hdr_size_in_bytes);
+  br(Assembler::EQ, done);
+  // note: for the remaining code to work, index must be a multiple of BytesPerWord
+#ifdef ASSERT
+  { Label L;
+    tst(index, BytesPerWord - 1);
+    br(Assembler::EQ, L);
+    stop("index is not a multiple of BytesPerWord");
+    bind(L);
+  }
+#endif
+
+  // Preserve obj
+  if (hdr_size_in_bytes)
+    add(obj, obj, hdr_size_in_bytes);
+  zero_memory(obj, index, t1);
+  if (hdr_size_in_bytes)
+    sub(obj, obj, hdr_size_in_bytes);
+
+  // 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_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);
+}
+
+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::header_size() * HeapWordSize;
+
+  initialize_header(obj, klass, noreg, t1, t2);
+
+  // 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);
+}
+
+void C1_MacroAssembler::remove_frame(int framesize) {
+  MacroAssembler::remove_frame(framesize + 2 * wordSize);
+}
+
+
+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