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# *****************************************************************
#
#               The Compcert verified compiler
#
#           Xavier Leroy, INRIA Paris-Rocquencourt
#
# Copyright (c) 2013 Institut National de Recherche en Informatique et
#  en Automatique.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#     * Redistributions of source code must retain the above copyright
#       notice, this list of conditions and the following disclaimer.
#     * Redistributions in binary form must reproduce the above copyright
#       notice, this list of conditions and the following disclaimer in the
#       documentation and/or other materials provided with the distribution.
#     * Neither the name of the <organization> nor the
#       names of its contributors may be used to endorse or promote products
#       derived from this software without specific prior written permission.
# 
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT
# HOLDER> BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
# EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
# PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
# LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
# NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# *********************************************************************

# Helper functions for 64-bit integer arithmetic.  IA32 version.
	
        .text

# Conversion float -> unsigned long

        .globl __i64_dtou
        .balign 16
__i64_dtou:
        subl $4, %esp
  # Change rounding mode to "round towards zero"
        fnstcw 0(%esp)
        movw 0(%esp), %ax
        movb $12, %ah
        movw %ax, 2(%esp)
        fldcw 2(%esp)
  # Compare argument with 2^63
        fldl (4+4)(%esp)
        flds LC1
        fucomp
        fnstsw %ax
        sahf
        jbe 1f                  # branch if not (ARG < 2^63)
  # Argument < 2^63: convert as is
        fistpll 8(%esp)
        movl 8(%esp), %eax
        movl 12(%esp), %edx
        jmp 2f
  # Argument > 2^63: offset ARG by -2^63, then convert, then offset RES by 2^63
1:      fsubs LC1
        fistpll 8(%esp)
        movl 8(%esp), %eax
        movl 12(%esp), %edx
        addl $0x80000000, %edx
  # Restore rounding mode
2:      fldcw 0(%esp)
        addl $4, %esp
        ret
        .type __i64_dtou, @function
        .size __i64_dtou, . - __i64_dtou

        .balign 4
LC1:    .long 0x5f000000        # 2^63 in single precision