From dc25573ed79a0d55c5a24b20474aa8504a758a2c Mon Sep 17 00:00:00 2001 From: David Monniaux Date: Sat, 2 Feb 2019 12:03:44 +0100 Subject: BearSSL --- test/monniaux/BearSSL/src/int/i15_ninv15.c | 38 ++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 test/monniaux/BearSSL/src/int/i15_ninv15.c (limited to 'test/monniaux/BearSSL/src/int/i15_ninv15.c') diff --git a/test/monniaux/BearSSL/src/int/i15_ninv15.c b/test/monniaux/BearSSL/src/int/i15_ninv15.c new file mode 100644 index 00000000..de3a3ba8 --- /dev/null +++ b/test/monniaux/BearSSL/src/int/i15_ninv15.c @@ -0,0 +1,38 @@ +/* + * Copyright (c) 2017 Thomas Pornin + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "inner.h" + +/* see inner.h */ +uint16_t +br_i15_ninv15(uint16_t x) +{ + uint32_t y; + + y = 2 - x; + y = MUL15(y, 2 - MUL15(x, y)); + y = MUL15(y, 2 - MUL15(x, y)); + y = MUL15(y, 2 - MUL15(x, y)); + return MUX(x & 1, -y, 0) & 0x7FFF; +} -- cgit