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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.  ARM version.

        .text

@@@ Shift right signed

	.global __i64_sar
__i64_sar:
        and r2, r2, #63         @ normalize amount to 0...63
        rsbs r3, r2, #32        @ r3 = 32 - amount
        ble 1f                  @ branch if <= 0, namely if amount >= 32
        mov r0, r0, lsr r2
        orr r0, r1, lsl r3
        mov r1, r1, asr r2
        bx lr
1:
        sub r2, r2, #32
        mov r0, r1, asr r2
        mov r1, r1, asr #31
        bx lr
	.type __i64_sar, %function
	.size __i64_sar, . - __i64_sar