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Diffstat (limited to 'runtime/powerpc/i64_dtos.s')
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diff --git a/runtime/powerpc/i64_dtos.s b/runtime/powerpc/i64_dtos.s new file mode 100644 index 0000000..56c6e4b --- /dev/null +++ b/runtime/powerpc/i64_dtos.s @@ -0,0 +1,89 @@ +# ***************************************************************** +# +# 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 signed long + + .balign 16 + .globl __i64_dtos +__i64_dtos: + 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 + srawi r10, r3, 31 # save sign of double in r10 + # 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, abs(double) is < 1.0 + blt 1f + cmpwi r5, 11 # if EXP >= 63 - 52, abs(double) is >= 2^63 + bge 2f + # extract true mantissa + rlwinm r3, r3, 0, 12, 31 # HI &= ~0xFFF00000 + oris r3, r3, 0x10 # HI |= 0x00100000 + # shift it appropriately + mflr r9 # save retaddr in r9 + cmpwi r5, 0 + blt 3f + bl __i64_shl # if EXP >= 0, shift left by EXP + b 4f +3: subfic r5, r5, 0 + bl __i64_shr # if EXP < 0, shift right by -EXP + # apply sign to result +4: mtlr r9 + xor r4, r4, r10 + xor r3, r3, r10 + subfc r4, r10, r4 + subfe r3, r10, r3 + blr + # Special cases +1: li r3, 0 # result is 0 + li r4, 0 + blr +2: cmpwi r10, 0 # result is MAX_SINT or MIN_SINT + bge 5f # depending on sign + li r4, -1 # result is MAX_SINT = 0x7FFF_FFFF + srwi r3, r4, 1 + blr +5: lis r3, 0x8000 # result is MIN_SINT = 0x8000_0000 + li r4, 0 + blr + .type __i64_dtos, @function + .size __i64_dtos, .-__i64_dtos +
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