rev 12409 : 8169177: aarch64: SIGSEGV when "-XX:+ZeroTLAB" is specified along with GC options
Summary: Add zero-initialization to C1 for fast TLAB refills
Reviewed-by: aph, drwhite
Contributed-by: kavitha.natarajan@linaro.org

   1 /*
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   3  * Copyright (c) 2014, 2015, Red Hat Inc. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
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  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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  25 
  26 #ifndef CPU_AARCH64_VM_C1_MACROASSEMBLER_AARCH64_HPP
  27 #define CPU_AARCH64_VM_C1_MACROASSEMBLER_AARCH64_HPP
  28 
  29 using MacroAssembler::build_frame;
  30 using MacroAssembler::null_check;
  31 
  32 // C1_MacroAssembler contains high-level macros for C1
  33 
  34  private:
  35   int _rsp_offset;    // track rsp changes
  36   // initialization
  37   void pd_init() { _rsp_offset = 0; }
  38 

  39 
  40  public:
  41   void try_allocate(
  42     Register obj,                      // result: pointer to object after successful allocation
  43     Register var_size_in_bytes,        // object size in bytes if unknown at compile time; invalid otherwise
  44     int      con_size_in_bytes,        // object size in bytes if   known at compile time
  45     Register t1,                       // temp register
  46     Register t2,                       // temp register
  47     Label&   slow_case                 // continuation point if fast allocation fails
  48   );
  49 
  50   void initialize_header(Register obj, Register klass, Register len, Register t1, Register t2);
  51   void initialize_body(Register obj, Register len_in_bytes, int hdr_size_in_bytes, Register t1);
  52 
  53   void float_cmp(bool is_float, int unordered_result,
  54                  FloatRegister f0, FloatRegister f1,
  55                  Register result);
  56 
  57   // locking
  58   // hdr     : must be r0, contents destroyed
  59   // obj     : must point to the object to lock, contents preserved
  60   // disp_hdr: must point to the displaced header location, contents preserved
  61   // scratch : scratch register, contents destroyed
  62   // returns code offset at which to add null check debug information
  63   int lock_object  (Register swap, Register obj, Register disp_hdr, Register scratch, Label& slow_case);
  64 
  65   // unlocking
  66   // hdr     : contents destroyed
  67   // obj     : must point to the object to lock, contents preserved
  68   // disp_hdr: must be r0 & must point to the displaced header location, contents destroyed
  69   void unlock_object(Register swap, Register obj, Register lock, Label& slow_case);
  70 
  71   void initialize_object(
  72     Register obj,                      // result: pointer to object after successful allocation
  73     Register klass,                    // object klass
  74     Register var_size_in_bytes,        // object size in bytes if unknown at compile time; invalid otherwise
  75     int      con_size_in_bytes,        // object size in bytes if   known at compile time
  76     Register t1,                       // temp register
  77     Register t2,                        // temp register
  78     bool     is_tlab_allocated         // the object was allocated in a TLAB; relevant for the implementation of ZeroTLAB
  79   );
  80 
  81   // allocation of fixed-size objects
  82   // (can also be used to allocate fixed-size arrays, by setting
  83   // hdr_size correctly and storing the array length afterwards)
  84   // obj        : will contain pointer to allocated object
  85   // t1, t2     : scratch registers - contents destroyed
  86   // header_size: size of object header in words
  87   // object_size: total size of object in words
  88   // slow_case  : exit to slow case implementation if fast allocation fails
  89   void allocate_object(Register obj, Register t1, Register t2, int header_size, int object_size, Register klass, Label& slow_case);
  90 
  91   enum {
  92     max_array_allocation_length = 0x00FFFFFF
  93   };
  94 
  95   // allocation of arrays
  96   // obj        : will contain pointer to allocated object
  97   // len        : array length in number of elements
  98   // t          : scratch register - contents destroyed
  99   // header_size: size of object header in words
 100   // f          : element scale factor
 101   // slow_case  : exit to slow case implementation if fast allocation fails
 102   void allocate_array(Register obj, Register len, Register t, Register t2, int header_size, int f, Register klass, Label& slow_case);
 103 
 104   int  rsp_offset() const { return _rsp_offset; }
 105   void set_rsp_offset(int n) { _rsp_offset = n; }
 106 
 107   void invalidate_registers(bool inv_r0, bool inv_r19, bool inv_r2, bool inv_r3, bool inv_r4, bool inv_r5) PRODUCT_RETURN;
 108 
 109   // This platform only uses signal-based null checks. The Label is not needed.
 110   void null_check(Register r, Label *Lnull = NULL) { MacroAssembler::null_check(r); }
 111 
 112 #endif // CPU_AARCH64_VM_C1_MACROASSEMBLER_AARCH64_HPP
--- EOF ---