# ***************************************************************** # # 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 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 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. PowerPC version. .text ## Signed remainder .balign 16 .globl __i64_smod __i64_smod: mflr r0 stw r0, 4(r1) # save return address in caller's frame mtctr r3 # save sign of result in CTR (sign of N) srawi r0, r3, 31 # take absolute value of N xor r4, r4, r0 # (i.e. N = N ^ r0 - r0, xor r3, r3, r0 # where r0 = 0 if N >= 0 and r0 = -1 if N < 0) subfc r4, r0, r4 subfe r3, r0, r3 srawi r0, r5, 31 # take absolute value of D xor r6, r6, r0 # (same trick) xor r5, r5, r0 subfc r6, r0, r6 subfe r5, r0, r5 bl __i64_udivmod # do unsigned division lwz r0, 4(r1) mtlr r0 # restore return address mfctr r0 srawi r0, r0, 31 # apply expected sign to remainder xor r4, r4, r0 # RES = R if CTR >= 0, -Q if CTR < 0 xor r3, r3, r0 subfc r4, r0, r4 subfe r3, r0, r3 blr .type __i64_smod, @function .size __i64_smod, .-__i64_smod