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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
# Shift right signed
# Note: IA32 shift instructions treat their amount (in %cl) modulo 32
.globl __i64_sar
.balign 16
__i64_sar:
movl 12(%esp), %ecx # ecx = shift amount, treated mod 64
testb $32, %cl
jne 1f
# shift amount < 32
movl 4(%esp), %eax
movl 8(%esp), %edx
shrdl %cl, %edx, %eax # eax = low(XH:XL >> amount)
sarl %cl, %edx # edx = XH >> amount (signed)
ret
# shift amount >= 32
1: movl 8(%esp), %eax
movl %eax, %edx
sarl %cl, %eax # eax = XH >> (amount - 32)
sarl $31, %edx # edx = sign of X
ret
.type __i64_sar, @function
.size __i64_sar, . - __i64_sar
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