hotspot/src/cpu/x86/vm/jniTypes_x86.hpp

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#ifndef CPU_X86_VM_JNITYPES_X86_HPP
#define CPU_X86_VM_JNITYPES_X86_HPP

#include "memory/allocation.hpp"
#include "oops/oop.hpp"
#include "prims/jni.h"

// This file holds platform-dependent routines used to write primitive jni
// types to the array of arguments passed into JavaCalls::call

class JNITypes : AllStatic {
  // These functions write a java primitive type (in native format)
  // to a java stack slot array to be passed as an argument to JavaCalls:calls.
  // I.e., they are functionally 'push' operations if they have a 'pos'
  // formal parameter.  Note that jlong's and jdouble's are written
  // _in reverse_ of the order in which they appear in the interpreter
  // stack.  This is because call stubs (see stubGenerator_sparc.cpp)
  // reverse the argument list constructed by JavaCallArguments (see
  // javaCalls.hpp).

private:

#ifndef AMD64
  // 32bit Helper routines.
  static inline void    put_int2r(jint *from, intptr_t *to)           { *(jint *)(to++) = from[1];
                                                                        *(jint *)(to  ) = from[0]; }
  static inline void    put_int2r(jint *from, intptr_t *to, int& pos) { put_int2r(from, to + pos); pos += 2; }
#endif // AMD64

public:
  // Ints are stored in native format in one JavaCallArgument slot at *to.
  static inline void    put_int(jint  from, intptr_t *to)           { *(jint *)(to +   0  ) =  from; }
  static inline void    put_int(jint  from, intptr_t *to, int& pos) { *(jint *)(to + pos++) =  from; }
  static inline void    put_int(jint *from, intptr_t *to, int& pos) { *(jint *)(to + pos++) = *from; }

#ifdef AMD64
  // Longs are stored in native format in one JavaCallArgument slot at
  // *(to+1).
  static inline void put_long(jlong  from, intptr_t *to) {
    *(jlong*) (to + 1) = from;
  }

  static inline void put_long(jlong  from, intptr_t *to, int& pos) {
    *(jlong*) (to + 1 + pos) = from;
    pos += 2;
  }

  static inline void put_long(jlong *from, intptr_t *to, int& pos) {
    *(jlong*) (to + 1 + pos) = *from;
    pos += 2;
  }
#else
  // Longs are stored in big-endian word format in two JavaCallArgument slots at *to.
  // The high half is in *to and the low half in *(to+1).
  static inline void    put_long(jlong  from, intptr_t *to)           { put_int2r((jint *)&from, to); }
  static inline void    put_long(jlong  from, intptr_t *to, int& pos) { put_int2r((jint *)&from, to, pos); }
  static inline void    put_long(jlong *from, intptr_t *to, int& pos) { put_int2r((jint *) from, to, pos); }
#endif // AMD64

  // Oops are stored in native format in one JavaCallArgument slot at *to.
  static inline void    put_obj(oop  from, intptr_t *to)           { *(oop *)(to +   0  ) =  from; }
  static inline void    put_obj(oop  from, intptr_t *to, int& pos) { *(oop *)(to + pos++) =  from; }
  static inline void    put_obj(oop *from, intptr_t *to, int& pos) { *(oop *)(to + pos++) = *from; }

  // Floats are stored in native format in one JavaCallArgument slot at *to.
  static inline void    put_float(jfloat  from, intptr_t *to)           { *(jfloat *)(to +   0  ) =  from;  }
  static inline void    put_float(jfloat  from, intptr_t *to, int& pos) { *(jfloat *)(to + pos++) =  from; }
  static inline void    put_float(jfloat *from, intptr_t *to, int& pos) { *(jfloat *)(to + pos++) = *from; }

#undef _JNI_SLOT_OFFSET
#ifdef AMD64
#define _JNI_SLOT_OFFSET 1
  // Doubles are stored in native word format in one JavaCallArgument
  // slot at *(to+1).
  static inline void put_double(jdouble  from, intptr_t *to) {
    *(jdouble*) (to + 1) = from;
  }

  static inline void put_double(jdouble  from, intptr_t *to, int& pos) {
    *(jdouble*) (to + 1 + pos) = from;
    pos += 2;
  }

  static inline void put_double(jdouble *from, intptr_t *to, int& pos) {
    *(jdouble*) (to + 1 + pos) = *from;
    pos += 2;
  }
#else
#define _JNI_SLOT_OFFSET 0
  // Doubles are stored in big-endian word format in two JavaCallArgument slots at *to.
  // The high half is in *to and the low half in *(to+1).
  static inline void    put_double(jdouble  from, intptr_t *to)           { put_int2r((jint *)&from, to); }
  static inline void    put_double(jdouble  from, intptr_t *to, int& pos) { put_int2r((jint *)&from, to, pos); }
  static inline void    put_double(jdouble *from, intptr_t *to, int& pos) { put_int2r((jint *) from, to, pos); }
#endif // AMD64


  // The get_xxx routines, on the other hand, actually _do_ fetch
  // java primitive types from the interpreter stack.
  // No need to worry about alignment on Intel.
  static inline jint    get_int   (intptr_t *from) { return *(jint *)   from; }
  static inline jlong   get_long  (intptr_t *from) { return *(jlong *)  (from + _JNI_SLOT_OFFSET); }
  static inline oop     get_obj   (intptr_t *from) { return *(oop *)    from; }
  static inline jfloat  get_float (intptr_t *from) { return *(jfloat *) from; }
  static inline jdouble get_double(intptr_t *from) { return *(jdouble *)(from + _JNI_SLOT_OFFSET); }
#undef _JNI_SLOT_OFFSET
};

#endif // CPU_X86_VM_JNITYPES_X86_HPP