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Diffstat (limited to 'runtime/powerpc/i64_dtou.s')
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diff --git a/runtime/powerpc/i64_dtou.s b/runtime/powerpc/i64_dtou.s new file mode 100644 index 0000000..d9638e6 --- /dev/null +++ b/runtime/powerpc/i64_dtou.s @@ -0,0 +1,77 @@ +# ***************************************************************** +# +# 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. PowerPC version. + + .text + +### Conversion from double float to unsigned long + + .balign 16 + .globl __i64_dtou +__i64_dtou: + stfdu f1, -16(r1) # extract LO (r4) and HI (r3) halves of double + lwz r3, 0(r1) + lwz r4, 4(r1) + addi r1, r1, 16 + cmpwi r3, 0 # is double < 0? + blt 1f # then it converts to 0 + # extract unbiased exponent ((HI & 0x7FF00000) >> 20) - (1023 + 52) + rlwinm r5, r3, 12, 21, 31 + addi r5, r5, -1075 + # check range of exponent + cmpwi r5, -52 # if EXP < -52, double is < 1.0 + blt 1f + cmpwi r5, 12 # if EXP >= 64 - 52, double is >= 2^64 + bge 2f + # extract true mantissa + rlwinm r3, r3, 0, 12, 31 # HI &= ~0xFFF00000 + oris r3, r3, 0x10 # HI |= 0x00100000 + # shift it appropriately + cmpwi r5, 0 + blt 3f + b __i64_shl # if EXP >= 0, shift left by EXP +3: subfic r5, r5, 0 + b __i64_shr # if EXP < 0, shift right by -EXP + # Special cases +1: li r3, 0 # result is 0 + li r4, 0 + blr +2: li r3, -1 # result is MAX_UINT + li r4, -1 + blr + .type __i64_dtou, @function + .size __i64_dtou, .-__i64_dtou + +
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