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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.
#include "sysdeps.h"
// Shift right signed
// Note: IA32 shift instructions treat their amount (in %cl) modulo 32
FUNCTION(__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
ENDFUNCTION(__i64_sar)
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