/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8 -*-│ │vi: set et ft=asm ts=8 tw=8 fenc=utf-8 :vi│ ╞══════════════════════════════════════════════════════════════════════════════╡ │ Copyright 2020 Justine Alexandra Roberts Tunney │ │ │ │ Permission to use, copy, modify, and/or distribute this software for │ │ any purpose with or without fee is hereby granted, provided that the │ │ above copyright notice and this permission notice appear in all copies. │ │ │ │ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │ │ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │ │ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │ │ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │ │ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │ │ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │ │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │ │ PERFORMANCE OF THIS SOFTWARE. │ ╚─────────────────────────────────────────────────────────────────────────────*/ #include "libc/macros.internal.h" // Support code for fast integer division by Si units. // // Division by magnums is described in Hacker's Delight and is // usually generated automatically by compilers, but sadly not // when we optimize for size and idiv goes at least 10x slower // so we do this which saves space while avoiding build tuning // // @param rdi is number to divide // @param cl is magnum #1 // @param rdx is magnum #2 // @return quotient tinydivsi: .leafprologue mov %rdi,%rax imul %rdx mov %rdx,%rax sar %cl,%rax sar $63,%rdi sub %rdi,%rax .leafepilogue .endfn tinydivsi,globl .source __FILE__