# ***************************************************************** # # 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 64 version. .text ### Conversion from signed long to single float .balign 16 .globl __compcert_i64_stof __compcert_i64_stof: rldimi r4, r3, 32, 0 # reassemble (r3,r4) as a 64-bit integer in r4 # Check whether -2^53 <= X < 2^53 sradi r5, r4, 53 addi r5, r5, 1 cmpldi r5, 2 blt 1f # X is large enough that double rounding can occur. # Avoid it by nudging X away from the points where double rounding # occurs (the "round to odd" technique) rldicl r5, r4, 0, 53 # extract bits 0 to 11 of X addi r5, r5, 0x7FF # r5 = (X & 0x7FF) + 0x7FF # bit 12 of r5 is 0 if all low 12 bits of X are 0, 1 otherwise # bits 13-63 of r5 are 0 or r4, r4, r5 # correct bit number 12 of X rldicr r4, r4, 0, 52 # set to 0 bits 0 to 11 of X # Convert to double, then round to single 1: stdu r4, -16(r1) lfd f1, 0(r1) fcfid f1, f1 frsp f1, f1 addi r1, r1, 16 blr .type __compcert_i64_stof, @function .size __compcert_i64_stof, .-__compcert_i64_stof