view src/share/vm/utilities/globalDefinitions_visCPP.hpp @ 1716:be3f9c242c9d

6948538: CMS: BOT walkers can fall into object allocation and initialization cracks Summary: GC workers now recognize an intermediate transient state of blocks which are allocated but have not yet completed initialization. blk_start() calls do not attempt to determine the size of a block in the transient state, rather waiting for the block to become initialized so that it is safe to query its size. Audited and ensured the order of initialization of object fields (klass, free bit and size) to respect block state transition protocol. Also included some new assertion checking code enabled in debug mode. Reviewed-by: chrisphi, johnc, poonam
author ysr
date Mon, 16 Aug 2010 15:58:42 -0700
parents c18cbe5936b8
children f95d63e2154a
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/*
 * Copyright (c) 1997, 2009, 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.
 *
 */

// This file holds compiler-dependent includes,
// globally used constants & types, class (forward)
// declarations and a few frequently used utility functions.

# include <ctype.h>
# include <string.h>
# include <stdarg.h>
# include <stdlib.h>
# include <stddef.h>// for offsetof
# include <io.h>    // for stream.cpp
# include <float.h> // for _isnan
# include <stdio.h> // for va_list
# include <time.h>
# include <fcntl.h>
// Need this on windows to get the math constants (e.g., M_PI).
#define _USE_MATH_DEFINES
# include <math.h>

// 4810578: varargs unsafe on 32-bit integer/64-bit pointer architectures
// When __cplusplus is defined, NULL is defined as 0 (32-bit constant) in
// system header files.  On 32-bit architectures, there is no problem.
// On 64-bit architectures, defining NULL as a 32-bit constant can cause
// problems with varargs functions: C++ integral promotion rules say for
// varargs, we pass the argument 0 as an int.  So, if NULL was passed to a
// varargs function it will remain 32-bits.  Depending on the calling
// convention of the machine, if the argument is passed on the stack then
// only 32-bits of the "NULL" pointer may be initialized to zero.  The
// other 32-bits will be garbage.  If the varargs function is expecting a
// pointer when it extracts the argument, then we may have a problem.
//
// Solution: For 64-bit architectures, redefine NULL as 64-bit constant 0.
#ifdef _LP64
#undef NULL
// 64-bit Windows uses a P64 data model (not LP64, although we define _LP64)
// Since longs are 32-bit we cannot use 0L here.  Use the Visual C++ specific
// 64-bit integer-suffix (i64) instead.
#define NULL 0i64
#else
#ifndef NULL
#define NULL 0
#endif
#endif

// NULL vs NULL_WORD:
// On Linux NULL is defined as a special type '__null'. Assigning __null to
// integer variable will cause gcc warning. Use NULL_WORD in places where a
// pointer is stored as integer value.
#define NULL_WORD NULL

// Compiler-specific primitive types
typedef unsigned __int8  uint8_t;
typedef unsigned __int16 uint16_t;
typedef unsigned __int32 uint32_t;
typedef unsigned __int64 uint64_t;

#ifdef _WIN64
typedef unsigned __int64 uintptr_t;
#else
typedef unsigned int uintptr_t;
#endif
typedef signed   __int8  int8_t;
typedef signed   __int16 int16_t;
typedef signed   __int32 int32_t;
typedef signed   __int64 int64_t;
#ifdef _WIN64
typedef signed   __int64 intptr_t;
typedef signed   __int64 ssize_t;
#else
typedef signed   int intptr_t;
typedef signed   int ssize_t;
#endif

//----------------------------------------------------------------------------------------------------
// Additional Java basic types

typedef unsigned char    jubyte;
typedef unsigned short   jushort;
typedef unsigned int     juint;
typedef unsigned __int64 julong;

//----------------------------------------------------------------------------------------------------
// Special (possibly not-portable) casts
// Cast floats into same-size integers and vice-versa w/o changing bit-pattern

inline jint    jint_cast   (jfloat  x)           { return *(jint*   )&x; }
inline jlong   jlong_cast  (jdouble x)           { return *(jlong*  )&x; }

inline jfloat  jfloat_cast (jint    x)           { return *(jfloat* )&x; }
inline jdouble jdouble_cast(jlong   x)           { return *(jdouble*)&x; }


//----------------------------------------------------------------------------------------------------
// Non-standard stdlib-like stuff:
inline int strcasecmp(const char *s1, const char *s2) { return _stricmp(s1,s2); }


//----------------------------------------------------------------------------------------------------
// Debugging

#if _WIN64
extern "C" void breakpoint();
#define BREAKPOINT ::breakpoint()
#else
#define BREAKPOINT __asm { int 3 }
#endif

//----------------------------------------------------------------------------------------------------
// Checking for nanness

inline int g_isnan(jfloat  f)                    { return _isnan(f); }
inline int g_isnan(jdouble f)                    { return _isnan(f); }

//----------------------------------------------------------------------------------------------------
// Checking for finiteness

inline int g_isfinite(jfloat  f)                 { return _finite(f); }
inline int g_isfinite(jdouble f)                 { return _finite(f); }

//----------------------------------------------------------------------------------------------------
// Constant for jlong (specifying an long long constant is C++ compiler specific)

// Build a 64bit integer constant on with Visual C++
#define CONST64(x)  (x ## i64)
#define UCONST64(x) ((uint64_t)CONST64(x))

const jlong min_jlong = CONST64(0x8000000000000000);
const jlong max_jlong = CONST64(0x7fffffffffffffff);

//----------------------------------------------------------------------------------------------------
// Miscellaneous

// Visual Studio 2005 deprecates POSIX names - use ISO C++ names instead
#if _MSC_VER >= 1400
#define open _open
#define close _close
#define read  _read
#define write _write
#define lseek _lseek
#define unlink _unlink
#define strdup _strdup
#endif

#pragma warning( disable : 4100 ) // unreferenced formal parameter
#pragma warning( disable : 4127 ) // conditional expression is constant
#pragma warning( disable : 4514 ) // unreferenced inline function has been removed
#pragma warning( disable : 4244 ) // possible loss of data
#pragma warning( disable : 4512 ) // assignment operator could not be generated
#pragma warning( disable : 4201 ) // nonstandard extension used : nameless struct/union (needed in windows.h)
#pragma warning( disable : 4511 ) // copy constructor could not be generated
#pragma warning( disable : 4291 ) // no matching operator delete found; memory will not be freed if initialization thows an exception
#if _MSC_VER >= 1400
#pragma warning( disable : 4996 ) // unsafe string functions. Same as define _CRT_SECURE_NO_WARNINGS/_CRT_SECURE_NO_DEPRICATE
#endif

inline int vsnprintf(char* buf, size_t count, const char* fmt, va_list argptr) {
  // If number of characters written == count, Windows doesn't write a
  // terminating NULL, so we do it ourselves.
  int ret = _vsnprintf(buf, count, fmt, argptr);
  if (count > 0) buf[count-1] = '\0';
  return ret;
}

// Portability macros
#define PRAGMA_INTERFACE
#define PRAGMA_IMPLEMENTATION
#define PRAGMA_IMPLEMENTATION_(arg)
#define VALUE_OBJ_CLASS_SPEC    : public _ValueObj

// Formatting.
#define FORMAT64_MODIFIER "I64"

#define offset_of(klass,field) offsetof(klass,field)