root/arch/parisc/math-emu/fpbits.h

INCLUDED FROM

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * Linux/PA-RISC Project (http://www.parisc-linux.org/)
   4  *
   5  * Floating-point emulation code
   6  *  Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.org>
   7  */
   8 
   9 #ifdef __NO_PA_HDRS
  10     PA header file -- do not include this header file for non-PA builds.
  11 #endif
  12 
  13 
  14 /*
  15  *  These macros are designed to be portable to all machines that have
  16  *  a wordsize greater than or equal to 32 bits that support the portable
  17  *  C compiler and the standard C preprocessor.  Wordsize (default 32)
  18  *  and bitfield assignment (default left-to-right,  unlike VAX, PDP-11)
  19  *  should be predefined using the constants HOSTWDSZ and BITFRL and
  20  *  the C compiler "-D" flag (e.g., -DHOSTWDSZ=36 -DBITFLR for the DEC-20).
  21  *  Note that the macro arguments assume that the integer being referenced
  22  *  is a 32-bit integer (right-justified on the 20) and that bit 0 is the
  23  *  most significant bit.
  24  */
  25 
  26 #ifndef HOSTWDSZ
  27 #define HOSTWDSZ        32
  28 #endif
  29 
  30 
  31 /*###########################  Macros  ######################################*/
  32 
  33 /*-------------------------------------------------------------------------
  34  * NewDeclareBitField_Reference - Declare a structure similar to the simulator
  35  * function "DeclBitfR" except its use is restricted to occur within a larger
  36  * enclosing structure or union definition.  This declaration is an unnamed
  37  * structure with the argument, name, as the member name and the argument,
  38  * uname, as the element name. 
  39  *----------------------------------------------------------------------- */
  40 #define Bitfield_extract(start, length, object)         \
  41     ((object) >> (HOSTWDSZ - (start) - (length)) &      \
  42     ((unsigned)-1 >> (HOSTWDSZ - (length))))
  43 
  44 #define Bitfield_signed_extract(start, length, object) \
  45     ((int)((object) << start) >> (HOSTWDSZ - (length)))
  46 
  47 #define Bitfield_mask(start, len, object)               \
  48     ((object) & (((unsigned)-1 >> (HOSTWDSZ-len)) << (HOSTWDSZ-start-len)))
  49 
  50 #define Bitfield_deposit(value,start,len,object)  object = \
  51     ((object) & ~(((unsigned)-1 >> (HOSTWDSZ-len)) << (HOSTWDSZ-start-len))) | \
  52     (((value) & ((unsigned)-1 >> (HOSTWDSZ-len))) << (HOSTWDSZ-start-len))