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/*

picoChip GCC support for 32-bit shift left.

Copyright (C) 2003, 2004, 2005  Free Software Foundation, Inc.
Contributed by picoChip Designs Ltd.
Maintained by Daniel Towner (daniel.towner@picochip.com)

This file is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.

In addition to the permissions in the GNU General Public License, the
Free Software Foundation gives you unlimited permission to link the
compiled version of this file into combinations with other programs,
and to distribute those combinations without any restriction coming
from the use of this file.  (The General Public License restrictions
do apply in other respects; for example, they cover modification of
the file, and distribution when not linked into a combine
executable.)

This file 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 for more details.

You should have received a copy of the GNU General Public License
along with this program; see the file COPYING.  If not, write to
the Free Software Foundation, 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA. */

#ifndef PICOCHIP
#error "Intended for compilation for PICOCHIP only."
#endif

typedef int HItype __attribute__ ((mode (HI)));
typedef unsigned int UHItype __attribute__ ((mode (HI)));
typedef unsigned int USItype __attribute__ ((mode (SI)));

typedef struct USIstruct {
  UHItype low, high;
} USIstruct;

typedef union USIunion {
  USItype l;
  USIstruct s;
} USIunion;

USItype __ashlsi3(USIunion value, HItype count) {
  USIunion result;
  int temp;

  /* Ignore a zero count until we get into the (count < 16)
     clause. This is slightly slower when shifting by zero, but faster
     and smaller in all other cases (due to the better scheduling
     opportunities available by putting the test near computational
     instructions. */
  /* if (count == 0) return value.l; */

  if (count < 16) {
    /* Shift low and high words by the count. */
    result.s.low = value.s.low << count;
    result.s.high = value.s.high << count;
     
    /* There is now a hole in the lower `count' bits of the high
       word. Shift the upper `count' bits of the low word into the
       high word. This is only required when the count is non-zero. */
    if (count != 0) {
      temp = 16 - count;
      temp = value.s.low >> temp;
      result.s.high |= temp;
    }
  
  } else {
    /* Shift the lower word of the source into the upper word of the
       result, and zero the result's lower word. */
    count -= 16;
    result.s.high = value.s.low << count;
    result.s.low = 0;

  }

  return result.l;

}