diff options
Diffstat (limited to 'runtime/powerpc/i64_shl.s')
| -rw-r--r-- | runtime/powerpc/i64_shl.s | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/runtime/powerpc/i64_shl.s b/runtime/powerpc/i64_shl.s new file mode 100644 index 0000000..d122068 --- /dev/null +++ b/runtime/powerpc/i64_shl.s @@ -0,0 +1,64 @@ +# ***************************************************************** +# +# 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 + +# Shift left + + .balign 16 + .globl __i64_shl +__i64_shl: +# On PowerPC, shift instructions with amount mod 64 >= 32 return 0 +# hi = (hi << amount) | (lo >> (32 - amount)) | (lo << (amount - 32)) +# lo = lo << amount +# if 0 <= amount < 32: +# (amount - 32) mod 64 >= 32, hence lo << (amount - 32) == 0 +# if 32 <= amount < 64: +# lo << amount == 0 +# (32 - amount) mod 64 >= 32, hence lo >> (32 - amount) == 0 + andi. r5, r5, 63 # take amount modulo 64 + subfic r6, r5, 32 # r6 = 32 - amount + addi r7, r5, -32 # r7 = amount - 32 + slw r3, r3, r5 + srw r0, r4, r6 + or r3, r3, r0 + slw r0, r4, r7 + or r3, r3, r0 + slw r4, r4, r5 + blr + .type __i64_shl, @function + .size __i64_shl, .-__i64_shl +
\ No newline at end of file |