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957c61cbbf
This change upgrades to GCC 12.3 and GNU binutils 2.42. The GNU linker appears to have changed things so that only a single de-duplicated str table is present in the binary, and it gets placed wherever the linker wants, regardless of what the linker script says. To cope with that we need to stop using .ident to embed licenses. As such, this change does significant work to revamp how third party licenses are defined in the codebase, using `.section .notice,"aR",@progbits`. This new GCC 12.3 toolchain has support for GNU indirect functions. It lets us support __target_clones__ for the first time. This is used for optimizing the performance of libc string functions such as strlen and friends so far on x86, by ensuring AVX systems favor a second codepath that uses VEX encoding. It shaves some latency off certain operations. It's a useful feature to have for scientific computing for the reasons explained by the test/libcxx/openmp_test.cc example which compiles for fifteen different microarchitectures. Thanks to the upgrades, it's now also possible to use newer instruction sets, such as AVX512FP16, VNNI. Cosmo now uses the %gs register on x86 by default for TLS. Doing it is helpful for any program that links `cosmo_dlopen()`. Such programs had to recompile their binaries at startup to change the TLS instructions. That's not great, since it means every page in the executable needs to be faulted. The work of rewriting TLS-related x86 opcodes, is moved to fixupobj.com instead. This is great news for MacOS x86 users, since we previously needed to morph the binary every time for that platform but now that's no longer necessary. The only platforms where we need fixup of TLS x86 opcodes at runtime are now Windows, OpenBSD, and NetBSD. On Windows we morph TLS to point deeper into the TIB, based on a TlsAlloc assignment, and on OpenBSD/NetBSD we morph %gs back into %fs since the kernels do not allow us to specify a value for the %gs register. OpenBSD users are now required to use APE Loader to run Cosmo binaries and assimilation is no longer possible. OpenBSD kernel needs to change to allow programs to specify a value for the %gs register, or it needs to stop marking executable pages loaded by the kernel as mimmutable(). This release fixes __constructor__, .ctor, .init_array, and lastly the .preinit_array so they behave the exact same way as glibc. We no longer use hex constants to define math.h symbols like M_PI.
565 lines
18 KiB
C
565 lines
18 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8 -*-│
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│ vi: set et ft=c ts=4 sts=4 sw=4 fenc=utf-8 :vi │
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╞══════════════════════════════════════════════════════════════════════════════╡
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│ Copyright (c) 2008-2016 Stefan Krah. All rights reserved. │
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│ │
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│ Redistribution and use in source and binary forms, with or without │
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│ modification, are permitted provided that the following conditions │
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│ are met: │
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│ │
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│ 1. Redistributions of source code must retain the above copyright │
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│ notice, this list of conditions and the following disclaimer. │
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│ │
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│ 2. Redistributions in binary form must reproduce the above copyright │
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│ notice, this list of conditions and the following disclaimer in │
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│ the documentation and/or other materials provided with the │
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│ distribution. │
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│ │
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│ THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND │
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│ ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE │
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│ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR │
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│ PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS │
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│ BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, │
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│ OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT │
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│ OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR │
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│ BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, │
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│ WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE │
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│ OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, │
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│ EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. │
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╚─────────────────────────────────────────────────────────────────────────────*/
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#include "third_party/python/Modules/_decimal/libmpdec/basearith.h"
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#include "third_party/python/Modules/_decimal/libmpdec/constants.h"
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#include "third_party/python/Modules/_decimal/libmpdec/mpdecimal.h"
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#include "third_party/python/Modules/_decimal/libmpdec/typearith.h"
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__static_yoink("libmpdec_notice");
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/*********************************************************************/
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/* Calculations in base MPD_RADIX */
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/*********************************************************************/
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/*
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* Knuth, TAOCP, Volume 2, 4.3.1:
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* w := sum of u (len m) and v (len n)
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* n > 0 and m >= n
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* The calling function has to handle a possible final carry.
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*/
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mpd_uint_t
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_mpd_baseadd(mpd_uint_t *w, const mpd_uint_t *u, const mpd_uint_t *v,
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mpd_size_t m, mpd_size_t n)
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{
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mpd_uint_t s;
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mpd_uint_t carry = 0;
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mpd_size_t i;
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assert(n > 0 && m >= n);
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/* add n members of u and v */
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for (i = 0; i < n; i++) {
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s = u[i] + (v[i] + carry);
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carry = (s < u[i]) | (s >= MPD_RADIX);
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w[i] = carry ? s-MPD_RADIX : s;
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}
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/* if there is a carry, propagate it */
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for (; carry && i < m; i++) {
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s = u[i] + carry;
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carry = (s == MPD_RADIX);
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w[i] = carry ? 0 : s;
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}
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/* copy the rest of u */
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for (; i < m; i++) {
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w[i] = u[i];
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}
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return carry;
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}
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/*
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* Add the contents of u to w. Carries are propagated further. The caller
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* has to make sure that w is big enough.
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*/
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void
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_mpd_baseaddto(mpd_uint_t *w, const mpd_uint_t *u, mpd_size_t n)
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{
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mpd_uint_t s;
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mpd_uint_t carry = 0;
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mpd_size_t i;
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if (n == 0) return;
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/* add n members of u to w */
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for (i = 0; i < n; i++) {
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s = w[i] + (u[i] + carry);
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carry = (s < w[i]) | (s >= MPD_RADIX);
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w[i] = carry ? s-MPD_RADIX : s;
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}
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/* if there is a carry, propagate it */
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for (; carry; i++) {
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s = w[i] + carry;
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carry = (s == MPD_RADIX);
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w[i] = carry ? 0 : s;
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}
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}
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/*
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* Add v to w (len m). The calling function has to handle a possible
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* final carry. Assumption: m > 0.
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*/
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mpd_uint_t
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_mpd_shortadd(mpd_uint_t *w, mpd_size_t m, mpd_uint_t v)
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{
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mpd_uint_t s;
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mpd_uint_t carry;
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mpd_size_t i;
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assert(m > 0);
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/* add v to w */
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s = w[0] + v;
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carry = (s < v) | (s >= MPD_RADIX);
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w[0] = carry ? s-MPD_RADIX : s;
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/* if there is a carry, propagate it */
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for (i = 1; carry && i < m; i++) {
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s = w[i] + carry;
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carry = (s == MPD_RADIX);
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w[i] = carry ? 0 : s;
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}
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return carry;
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}
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/* Increment u. The calling function has to handle a possible carry. */
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mpd_uint_t
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_mpd_baseincr(mpd_uint_t *u, mpd_size_t n)
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{
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mpd_uint_t s;
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mpd_uint_t carry = 1;
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mpd_size_t i;
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assert(n > 0);
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/* if there is a carry, propagate it */
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for (i = 0; carry && i < n; i++) {
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s = u[i] + carry;
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carry = (s == MPD_RADIX);
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u[i] = carry ? 0 : s;
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}
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return carry;
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}
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/*
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* Knuth, TAOCP, Volume 2, 4.3.1:
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* w := difference of u (len m) and v (len n).
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* number in u >= number in v;
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*/
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void
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_mpd_basesub(mpd_uint_t *w, const mpd_uint_t *u, const mpd_uint_t *v,
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mpd_size_t m, mpd_size_t n)
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{
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mpd_uint_t d;
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mpd_uint_t borrow = 0;
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mpd_size_t i;
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assert(m > 0 && n > 0);
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/* subtract n members of v from u */
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for (i = 0; i < n; i++) {
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d = u[i] - (v[i] + borrow);
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borrow = (u[i] < d);
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w[i] = borrow ? d + MPD_RADIX : d;
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}
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/* if there is a borrow, propagate it */
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for (; borrow && i < m; i++) {
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d = u[i] - borrow;
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borrow = (u[i] == 0);
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w[i] = borrow ? MPD_RADIX-1 : d;
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}
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/* copy the rest of u */
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for (; i < m; i++) {
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w[i] = u[i];
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}
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}
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/*
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* Subtract the contents of u from w. w is larger than u. Borrows are
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* propagated further, but eventually w can absorb the final borrow.
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*/
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void
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_mpd_basesubfrom(mpd_uint_t *w, const mpd_uint_t *u, mpd_size_t n)
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{
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mpd_uint_t d;
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mpd_uint_t borrow = 0;
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mpd_size_t i;
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if (n == 0) return;
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/* subtract n members of u from w */
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for (i = 0; i < n; i++) {
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d = w[i] - (u[i] + borrow);
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borrow = (w[i] < d);
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w[i] = borrow ? d + MPD_RADIX : d;
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}
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/* if there is a borrow, propagate it */
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for (; borrow; i++) {
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d = w[i] - borrow;
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borrow = (w[i] == 0);
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w[i] = borrow ? MPD_RADIX-1 : d;
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}
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}
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/* w := product of u (len n) and v (single word) */
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void
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_mpd_shortmul(mpd_uint_t *w, const mpd_uint_t *u, mpd_size_t n, mpd_uint_t v)
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{
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mpd_uint_t hi, lo;
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mpd_uint_t carry = 0;
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mpd_size_t i;
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assert(n > 0);
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for (i=0; i < n; i++) {
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_mpd_mul_words(&hi, &lo, u[i], v);
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lo = carry + lo;
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if (lo < carry) hi++;
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_mpd_div_words_r(&carry, &w[i], hi, lo);
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}
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w[i] = carry;
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}
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/*
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* Knuth, TAOCP, Volume 2, 4.3.1:
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* w := product of u (len m) and v (len n)
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* w must be initialized to zero
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*/
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void
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_mpd_basemul(mpd_uint_t *w, const mpd_uint_t *u, const mpd_uint_t *v,
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mpd_size_t m, mpd_size_t n)
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{
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mpd_uint_t hi, lo;
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mpd_uint_t carry;
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mpd_size_t i, j;
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assert(m > 0 && n > 0);
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for (j=0; j < n; j++) {
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carry = 0;
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for (i=0; i < m; i++) {
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_mpd_mul_words(&hi, &lo, u[i], v[j]);
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lo = w[i+j] + lo;
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if (lo < w[i+j]) hi++;
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lo = carry + lo;
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if (lo < carry) hi++;
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_mpd_div_words_r(&carry, &w[i+j], hi, lo);
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}
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w[j+m] = carry;
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}
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}
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/*
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* Knuth, TAOCP Volume 2, 4.3.1, exercise 16:
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* w := quotient of u (len n) divided by a single word v
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*/
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mpd_uint_t
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_mpd_shortdiv(mpd_uint_t *w, const mpd_uint_t *u, mpd_size_t n, mpd_uint_t v)
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{
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mpd_uint_t hi, lo;
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mpd_uint_t rem = 0;
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mpd_size_t i;
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assert(n > 0);
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for (i=n-1; i != MPD_SIZE_MAX; i--) {
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_mpd_mul_words(&hi, &lo, rem, MPD_RADIX);
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lo = u[i] + lo;
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if (lo < u[i]) hi++;
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_mpd_div_words(&w[i], &rem, hi, lo, v);
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}
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return rem;
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}
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/*
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* Knuth, TAOCP Volume 2, 4.3.1:
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* q, r := quotient and remainder of uconst (len nplusm)
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* divided by vconst (len n)
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* nplusm >= n
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*
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* If r is not NULL, r will contain the remainder. If r is NULL, the
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* return value indicates if there is a remainder: 1 for true, 0 for
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* false. A return value of -1 indicates an error.
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*/
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int
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_mpd_basedivmod(mpd_uint_t *q, mpd_uint_t *r,
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const mpd_uint_t *uconst, const mpd_uint_t *vconst,
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mpd_size_t nplusm, mpd_size_t n)
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{
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mpd_uint_t ustatic[MPD_MINALLOC_MAX];
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mpd_uint_t vstatic[MPD_MINALLOC_MAX];
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mpd_uint_t *u = ustatic;
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mpd_uint_t *v = vstatic;
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mpd_uint_t d, qhat, rhat, w2[2];
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mpd_uint_t hi, lo, x;
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mpd_uint_t carry;
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mpd_size_t i, j, m;
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int retval = 0;
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assert(n > 1 && nplusm >= n);
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m = sub_size_t(nplusm, n);
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/* D1: normalize */
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d = MPD_RADIX / (vconst[n-1] + 1);
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if (nplusm >= MPD_MINALLOC_MAX) {
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if ((u = mpd_alloc(nplusm+1, sizeof *u)) == NULL) {
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return -1;
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}
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}
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if (n >= MPD_MINALLOC_MAX) {
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if ((v = mpd_alloc(n+1, sizeof *v)) == NULL) {
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mpd_free(u);
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return -1;
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}
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}
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_mpd_shortmul(u, uconst, nplusm, d);
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_mpd_shortmul(v, vconst, n, d);
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/* D2: loop */
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for (j=m; j != MPD_SIZE_MAX; j--) {
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/* D3: calculate qhat and rhat */
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rhat = _mpd_shortdiv(w2, u+j+n-1, 2, v[n-1]);
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qhat = w2[1] * MPD_RADIX + w2[0];
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while (1) {
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if (qhat < MPD_RADIX) {
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_mpd_singlemul(w2, qhat, v[n-2]);
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if (w2[1] <= rhat) {
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if (w2[1] != rhat || w2[0] <= u[j+n-2]) {
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break;
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}
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}
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}
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qhat -= 1;
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rhat += v[n-1];
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if (rhat < v[n-1] || rhat >= MPD_RADIX) {
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break;
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}
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}
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/* D4: multiply and subtract */
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carry = 0;
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for (i=0; i <= n; i++) {
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_mpd_mul_words(&hi, &lo, qhat, v[i]);
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lo = carry + lo;
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if (lo < carry) hi++;
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_mpd_div_words_r(&hi, &lo, hi, lo);
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x = u[i+j] - lo;
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carry = (u[i+j] < x);
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u[i+j] = carry ? x+MPD_RADIX : x;
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carry += hi;
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}
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q[j] = qhat;
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/* D5: test remainder */
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if (carry) {
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q[j] -= 1;
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/* D6: add back */
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(void)_mpd_baseadd(u+j, u+j, v, n+1, n);
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}
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}
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/* D8: unnormalize */
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if (r != NULL) {
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_mpd_shortdiv(r, u, n, d);
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/* we are not interested in the return value here */
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retval = 0;
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}
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else {
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retval = !_mpd_isallzero(u, n);
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}
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if (u != ustatic) mpd_free(u);
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if (v != vstatic) mpd_free(v);
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return retval;
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}
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/*
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* Left shift of src by 'shift' digits; src may equal dest.
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*
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* dest := area of n mpd_uint_t with space for srcdigits+shift digits.
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* src := coefficient with length m.
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*
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* The case splits in the function are non-obvious. The following
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* equations might help:
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*
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* Let msdigits denote the number of digits in the most significant
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* word of src. Then 1 <= msdigits <= rdigits.
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*
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* 1) shift = q * rdigits + r
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* 2) srcdigits = qsrc * rdigits + msdigits
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* 3) destdigits = shift + srcdigits
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* = q * rdigits + r + qsrc * rdigits + msdigits
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* = q * rdigits + (qsrc * rdigits + (r + msdigits))
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*
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* The result has q zero words, followed by the coefficient that
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* is left-shifted by r. The case r == 0 is trivial. For r > 0, it
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* is important to keep in mind that we always read m source words,
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* but write m+1 destination words if r + msdigits > rdigits, m words
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* otherwise.
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*/
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void
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_mpd_baseshiftl(mpd_uint_t *dest, mpd_uint_t *src, mpd_size_t n, mpd_size_t m,
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mpd_size_t shift)
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{
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mpd_uint_t l=l, lprev=lprev, h=h; /* b/c warnings */
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mpd_uint_t q, r;
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mpd_uint_t ph;
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assert(m > 0 && n >= m);
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_mpd_div_word(&q, &r, (mpd_uint_t)shift, MPD_RDIGITS);
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if (r != 0) {
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ph = mpd_pow10[r];
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--m; --n;
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_mpd_divmod_pow10(&h, &lprev, src[m--], MPD_RDIGITS-r);
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if (h != 0) { /* r + msdigits > rdigits <==> h != 0 */
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dest[n--] = h;
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}
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/* write m-1 shifted words */
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for (; m != MPD_SIZE_MAX; m--,n--) {
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_mpd_divmod_pow10(&h, &l, src[m], MPD_RDIGITS-r);
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dest[n] = ph * lprev + h;
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lprev = l;
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}
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/* write least significant word */
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dest[q] = ph * lprev;
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}
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else {
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while (--m != MPD_SIZE_MAX) {
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dest[m+q] = src[m];
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}
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}
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mpd_uint_zero(dest, q);
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}
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/*
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* Right shift of src by 'shift' digits; src may equal dest.
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* Assumption: srcdigits-shift > 0.
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*
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* dest := area with space for srcdigits-shift digits.
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* src := coefficient with length 'slen'.
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*
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* The case splits in the function rely on the following equations:
|
|
*
|
|
* Let msdigits denote the number of digits in the most significant
|
|
* word of src. Then 1 <= msdigits <= rdigits.
|
|
*
|
|
* 1) shift = q * rdigits + r
|
|
* 2) srcdigits = qsrc * rdigits + msdigits
|
|
* 3) destdigits = srcdigits - shift
|
|
* = qsrc * rdigits + msdigits - (q * rdigits + r)
|
|
* = (qsrc - q) * rdigits + msdigits - r
|
|
*
|
|
* Since destdigits > 0 and 1 <= msdigits <= rdigits:
|
|
*
|
|
* 4) qsrc >= q
|
|
* 5) qsrc == q ==> msdigits > r
|
|
*
|
|
* The result has slen-q words if msdigits > r, slen-q-1 words otherwise.
|
|
*/
|
|
mpd_uint_t
|
|
_mpd_baseshiftr(mpd_uint_t *dest, mpd_uint_t *src, mpd_size_t slen,
|
|
mpd_size_t shift)
|
|
{
|
|
/* spurious uninitialized warnings */
|
|
mpd_uint_t l=l, h=h, hprev=hprev; /* low, high, previous high */
|
|
mpd_uint_t rnd, rest; /* rounding digit, rest */
|
|
mpd_uint_t q, r;
|
|
mpd_size_t i, j;
|
|
mpd_uint_t ph;
|
|
assert(slen > 0);
|
|
_mpd_div_word(&q, &r, (mpd_uint_t)shift, MPD_RDIGITS);
|
|
rnd = rest = 0;
|
|
if (r != 0) {
|
|
ph = mpd_pow10[MPD_RDIGITS-r];
|
|
_mpd_divmod_pow10(&hprev, &rest, src[q], r);
|
|
_mpd_divmod_pow10(&rnd, &rest, rest, r-1);
|
|
if (rest == 0 && q > 0) {
|
|
rest = !_mpd_isallzero(src, q);
|
|
}
|
|
/* write slen-q-1 words */
|
|
for (j=0,i=q+1; i<slen; i++,j++) {
|
|
_mpd_divmod_pow10(&h, &l, src[i], r);
|
|
dest[j] = ph * l + hprev;
|
|
hprev = h;
|
|
}
|
|
/* write most significant word */
|
|
if (hprev != 0) { /* always the case if slen==q-1 */
|
|
dest[j] = hprev;
|
|
}
|
|
}
|
|
else {
|
|
if (q > 0) {
|
|
_mpd_divmod_pow10(&rnd, &rest, src[q-1], MPD_RDIGITS-1);
|
|
/* is there any non-zero digit below rnd? */
|
|
if (rest == 0) rest = !_mpd_isallzero(src, q-1);
|
|
}
|
|
for (j = 0; j < slen-q; j++) {
|
|
dest[j] = src[q+j];
|
|
}
|
|
}
|
|
/* 0-4 ==> rnd+rest < 0.5 */
|
|
/* 5 ==> rnd+rest == 0.5 */
|
|
/* 6-9 ==> rnd+rest > 0.5 */
|
|
return (rnd == 0 || rnd == 5) ? rnd + !!rest : rnd;
|
|
}
|
|
|
|
/*********************************************************************/
|
|
/* Calculations in base b */
|
|
/*********************************************************************/
|
|
|
|
/*
|
|
* Add v to w (len m). The calling function has to handle a possible
|
|
* final carry. Assumption: m > 0.
|
|
*/
|
|
mpd_uint_t
|
|
_mpd_shortadd_b(mpd_uint_t *w, mpd_size_t m, mpd_uint_t v, mpd_uint_t b)
|
|
{
|
|
mpd_uint_t s;
|
|
mpd_uint_t carry;
|
|
mpd_size_t i;
|
|
assert(m > 0);
|
|
/* add v to w */
|
|
s = w[0] + v;
|
|
carry = (s < v) | (s >= b);
|
|
w[0] = carry ? s-b : s;
|
|
/* if there is a carry, propagate it */
|
|
for (i = 1; carry && i < m; i++) {
|
|
s = w[i] + carry;
|
|
carry = (s == b);
|
|
w[i] = carry ? 0 : s;
|
|
}
|
|
return carry;
|
|
}
|
|
|
|
/* w := product of u (len n) and v (single word). Return carry. */
|
|
mpd_uint_t
|
|
_mpd_shortmul_c(mpd_uint_t *w, const mpd_uint_t *u, mpd_size_t n, mpd_uint_t v)
|
|
{
|
|
mpd_uint_t hi, lo;
|
|
mpd_uint_t carry = 0;
|
|
mpd_size_t i;
|
|
assert(n > 0);
|
|
for (i=0; i < n; i++) {
|
|
_mpd_mul_words(&hi, &lo, u[i], v);
|
|
lo = carry + lo;
|
|
if (lo < carry) hi++;
|
|
_mpd_div_words_r(&carry, &w[i], hi, lo);
|
|
}
|
|
return carry;
|
|
}
|
|
|
|
/* w := product of u (len n) and v (single word) */
|
|
mpd_uint_t
|
|
_mpd_shortmul_b(mpd_uint_t *w, const mpd_uint_t *u, mpd_size_t n,
|
|
mpd_uint_t v, mpd_uint_t b)
|
|
{
|
|
mpd_uint_t hi, lo;
|
|
mpd_uint_t carry = 0;
|
|
mpd_size_t i;
|
|
assert(n > 0);
|
|
for (i=0; i < n; i++) {
|
|
_mpd_mul_words(&hi, &lo, u[i], v);
|
|
lo = carry + lo;
|
|
if (lo < carry) hi++;
|
|
_mpd_div_words(&carry, &w[i], hi, lo, b);
|
|
}
|
|
return carry;
|
|
}
|
|
|
|
/*
|
|
* Knuth, TAOCP Volume 2, 4.3.1, exercise 16:
|
|
* w := quotient of u (len n) divided by a single word v
|
|
*/
|
|
mpd_uint_t
|
|
_mpd_shortdiv_b(mpd_uint_t *w, const mpd_uint_t *u, mpd_size_t n,
|
|
mpd_uint_t v, mpd_uint_t b)
|
|
{
|
|
mpd_uint_t hi, lo;
|
|
mpd_uint_t rem = 0;
|
|
mpd_size_t i;
|
|
assert(n > 0);
|
|
for (i=n-1; i != MPD_SIZE_MAX; i--) {
|
|
_mpd_mul_words(&hi, &lo, rem, b);
|
|
lo = u[i] + lo;
|
|
if (lo < u[i]) hi++;
|
|
_mpd_div_words(&w[i], &rem, hi, lo, v);
|
|
}
|
|
return rem;
|
|
}
|