os: implement ExpandUnsignedValueToAscii

Nintendo does this as of latest firmware.

It's desirable because it removes the only usage of util::SNPrintf() from os library,
which means programs which don't otherwise use SNPrintf do not need to link it into .text.

This saves ~0xD40 of .text as of time-of-commit when successfully unlinking, and e.g.
reduces our sm (and other modules) memory size by a page.
This commit is contained in:
Michael Scire 2021-09-29 13:42:11 -07:00
parent 1e7a327a25
commit 15ff64e03a
3 changed files with 69 additions and 1 deletions

View file

@ -19,6 +19,7 @@
#include "os_waitable_holder_base.hpp"
#include "os_waitable_holder_impl.hpp"
#include "os_waitable_object_list.hpp"
#include "os_utility.hpp"
namespace ams::os::impl {
@ -223,7 +224,8 @@ namespace ams::os::impl {
constexpr size_t ThreadNamePrefixSize = sizeof(ThreadNamePrefix) - 1;
const u64 func = reinterpret_cast<u64>(thread->function);
static_assert(ThreadNamePrefixSize + sizeof(func) * 2 + 1 <= sizeof(thread->name_buffer));
util::SNPrintf(thread->name_buffer, sizeof(thread->name_buffer), "%s%016lX", ThreadNamePrefix, func);
std::memcpy(thread->name_buffer, ThreadNamePrefix, ThreadNamePrefixSize);
os::impl::ExpandUnsignedValueToAscii(thread->name_buffer + ThreadNamePrefixSize, func);
}
thread->name_pointer = thread->name_buffer;

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@ -0,0 +1,42 @@
/*
* Copyright (c) 2018-2020 Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stratosphere.hpp>
#include "os_utility.hpp"
namespace ams::os::impl {
void ExpandUnsignedValueToAscii(char *dst, u64 value) {
/* Determine size needed. */
constexpr size_t SizeNeeded = (BITSIZEOF(value) / 4) * sizeof(char);
/* Write null-terminator. */
dst[SizeNeeded] = '\x00';
/* Write characters. */
for (size_t i = 0; i < SizeNeeded; ++i) {
/* Determine current character. */
const auto nybble = (value & 0xF);
const char cur_c = (nybble < 10) ? ('0' + nybble) : ('A' + nybble - 10);
/* Write current character. */
dst[SizeNeeded - 1 - i] = cur_c;
/* Shift to next nybble. */
value >>= 4;
}
}
}

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@ -0,0 +1,24 @@
/*
* Copyright (c) 2018-2020 Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include "os_waitable_holder_base.hpp"
#include "os_waitable_manager_impl.hpp"
namespace ams::os::impl {
void ExpandUnsignedValueToAscii(char *dst, u64 value);
}