https://github.com/ahmedbougacha created https://github.com/llvm/llvm-project/pull/94394
Start building it as part of the library, with some minor tweaks compared to the reference implementation: - clang-format to match libSupport - remove tracing support - add file header - templatize cROUNDS/dROUNDS, as well as 8B/16B result type - replace assert with static_assert - return the result directly, as uint64_t/uint128_t - remove big-endian support - use LLVM_FALLTHROUGH - remove tracing support The siphash function itself isn't used yet, and will be in a follow-up commit. >From 12bb6238aa0e7f90342aa194e54a8286e3e35dbd Mon Sep 17 00:00:00 2001 From: Ahmed Bougacha <ah...@bougacha.org> Date: Tue, 4 Jun 2024 12:41:47 -0700 Subject: [PATCH 1/3] [Support] Reformat SipHash.cpp to match libSupport. While there, give it our usual file header and an acknowledgement, and remove the imported README.md.SipHash. --- llvm/lib/Support/README.md.SipHash | 126 -------------- llvm/lib/Support/SipHash.cpp | 264 ++++++++++++++--------------- 2 files changed, 129 insertions(+), 261 deletions(-) delete mode 100644 llvm/lib/Support/README.md.SipHash diff --git a/llvm/lib/Support/README.md.SipHash b/llvm/lib/Support/README.md.SipHash deleted file mode 100644 index 4de3cd1854681..0000000000000 --- a/llvm/lib/Support/README.md.SipHash +++ /dev/null @@ -1,126 +0,0 @@ -# SipHash - -[](http://creativecommons.org/publicdomain/zero/1.0/) - -[](https://opensource.org/licenses/MIT) - - -SipHash is a family of pseudorandom functions (PRFs) optimized for speed on short messages. -This is the reference C code of SipHash: portable, simple, optimized for clarity and debugging. - -SipHash was designed in 2012 by [Jean-Philippe Aumasson](https://aumasson.jp) -and [Daniel J. Bernstein](https://cr.yp.to) as a defense against [hash-flooding -DoS attacks](https://aumasson.jp/siphash/siphashdos_29c3_slides.pdf). - -SipHash is: - -* *Simpler and faster* on short messages than previous cryptographic -algorithms, such as MACs based on universal hashing. - -* *Competitive in performance* with insecure non-cryptographic algorithms, such as [fhhash](https://github.com/cbreeden/fxhash). - -* *Cryptographically secure*, with no sign of weakness despite multiple [cryptanalysis](https://eprint.iacr.org/2019/865) [projects](https://eprint.iacr.org/2019/865) by leading cryptographers. - -* *Battle-tested*, with successful integration in OSs (Linux kernel, OpenBSD, -FreeBSD, FreeRTOS), languages (Perl, Python, Ruby, etc.), libraries (OpenSSL libcrypto, -Sodium, etc.) and applications (Wireguard, Redis, etc.). - -As a secure pseudorandom function (a.k.a. keyed hash function), SipHash can also be used as a secure message authentication code (MAC). -But SipHash is *not a hash* in the sense of general-purpose key-less hash function such as BLAKE3 or SHA-3. -SipHash should therefore always be used with a secret key in order to be secure. - - -## Variants - -The default SipHash is *SipHash-2-4*: it takes a 128-bit key, does 2 compression -rounds, 4 finalization rounds, and returns a 64-bit tag. - -Variants can use a different number of rounds. For example, we proposed *SipHash-4-8* as a conservative version. - -The following versions are not described in the paper but were designed and analyzed to fulfill applications' needs: - -* *SipHash-128* returns a 128-bit tag instead of 64-bit. Versions with specified number of rounds are SipHash-2-4-128, SipHash4-8-128, and so on. - -* *HalfSipHash* works with 32-bit words instead of 64-bit, takes a 64-bit key, -and returns 32-bit or 64-bit tags. For example, HalfSipHash-2-4-32 has 2 -compression rounds, 4 finalization rounds, and returns a 32-bit tag. - - -## Security - -(Half)SipHash-*c*-*d* with *c* ≥ 2 and *d* ≥ 4 is expected to provide the maximum PRF -security for any function with the same key and output size. - -The standard PRF security goal allow the attacker access to the output of SipHash on messages chosen adaptively by the attacker. - -Security is limited by the key size (128 bits for SipHash), such that -attackers searching 2<sup>*s*</sup> keys have chance 2<sup>*s*−128</sup> of finding -the SipHash key. -Security is also limited by the output size. In particular, when -SipHash is used as a MAC, an attacker who blindly tries 2<sup>*s*</sup> tags will -succeed with probability 2<sup>*s*-*t*</sup>, if *t* is that tag's bit size. - - -## Research - -* [Research paper](https://www.aumasson.jp/siphash/siphash.pdf) "SipHash: a fast short-input PRF" (accepted at INDOCRYPT 2012) -* [Slides](https://cr.yp.to/talks/2012.12.12/slides.pdf) of the presentation of SipHash at INDOCRYPT 2012 (Bernstein) -* [Slides](https://www.aumasson.jp/siphash/siphash_slides.pdf) of the presentation of SipHash at the DIAC workshop (Aumasson) - - -## Usage - -Running - -```sh - make -``` - -will build tests for - -* SipHash-2-4-64 -* SipHash-2-4-128 -* HalfSipHash-2-4-32 -* HalfSipHash-2-4-64 - - -```C - ./test -``` - -verifies 64 test vectors, and - -```C - ./debug -``` - -does the same and prints intermediate values. - -The code can be adapted to implement SipHash-*c*-*d*, the version of SipHash -with *c* compression rounds and *d* finalization rounds, by defining `cROUNDS` -or `dROUNDS` when compiling. This can be done with `-D` command line arguments -to many compilers such as below. - -```sh -gcc -Wall --std=c99 -DcROUNDS=2 -DdROUNDS=4 siphash.c halfsiphash.c test.c -o test -``` - -The `makefile` also takes *c* and *d* rounds values as parameters. - -```sh -make cROUNDS=2 dROUNDS=4 -``` - -Obviously, if the number of rounds is modified then the test vectors -won't verify. - -## Intellectual property - -This code is copyright (c) 2014-2023 Jean-Philippe Aumasson, Daniel J. -Bernstein. It is multi-licensed under - -* [CC0](./LICENCE_CC0) -* [MIT](./LICENSE_MIT). -* [Apache 2.0 with LLVM exceptions](./LICENSE_A2LLVM). - diff --git a/llvm/lib/Support/SipHash.cpp b/llvm/lib/Support/SipHash.cpp index c6d16e205521d..f31023740011f 100644 --- a/llvm/lib/Support/SipHash.cpp +++ b/llvm/lib/Support/SipHash.cpp @@ -1,25 +1,19 @@ -/* - SipHash reference C implementation - - Copyright (c) 2012-2022 Jean-Philippe Aumasson - <jeanphilippe.aumas...@gmail.com> - Copyright (c) 2012-2014 Daniel J. Bernstein <d...@cr.yp.to> - - To the extent possible under law, the author(s) have dedicated all copyright - and related and neighboring rights to this software to the public domain - worldwide. This software is distributed without any warranty. - - You should have received a copy of the CC0 Public Domain Dedication along - with - this software. If not, see - <http://creativecommons.org/publicdomain/zero/1.0/>. - */ +//===--- SipHash.cpp - An ABI-stable string hash --------------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// #include "siphash.h" #include <assert.h> #include <stddef.h> #include <stdint.h> +// Lightly adapted from the SipHash reference C implementation by +// Jean-Philippe Aumasson and Daniel J. Bernstein. + /* default: SipHash-2-4 */ #ifndef cROUNDS #define cROUNDS 2 @@ -31,49 +25,49 @@ #define ROTL(x, b) (uint64_t)(((x) << (b)) | ((x) >> (64 - (b)))) #define U32TO8_LE(p, v) \ - (p)[0] = (uint8_t)((v)); \ - (p)[1] = (uint8_t)((v) >> 8); \ - (p)[2] = (uint8_t)((v) >> 16); \ - (p)[3] = (uint8_t)((v) >> 24); + (p)[0] = (uint8_t)((v)); \ + (p)[1] = (uint8_t)((v) >> 8); \ + (p)[2] = (uint8_t)((v) >> 16); \ + (p)[3] = (uint8_t)((v) >> 24); #define U64TO8_LE(p, v) \ - U32TO8_LE((p), (uint32_t)((v))); \ - U32TO8_LE((p) + 4, (uint32_t)((v) >> 32)); + U32TO8_LE((p), (uint32_t)((v))); \ + U32TO8_LE((p) + 4, (uint32_t)((v) >> 32)); #define U8TO64_LE(p) \ - (((uint64_t)((p)[0])) | ((uint64_t)((p)[1]) << 8) | \ - ((uint64_t)((p)[2]) << 16) | ((uint64_t)((p)[3]) << 24) | \ - ((uint64_t)((p)[4]) << 32) | ((uint64_t)((p)[5]) << 40) | \ - ((uint64_t)((p)[6]) << 48) | ((uint64_t)((p)[7]) << 56)) + (((uint64_t)((p)[0])) | ((uint64_t)((p)[1]) << 8) | \ + ((uint64_t)((p)[2]) << 16) | ((uint64_t)((p)[3]) << 24) | \ + ((uint64_t)((p)[4]) << 32) | ((uint64_t)((p)[5]) << 40) | \ + ((uint64_t)((p)[6]) << 48) | ((uint64_t)((p)[7]) << 56)) #define SIPROUND \ - do { \ - v0 += v1; \ - v1 = ROTL(v1, 13); \ - v1 ^= v0; \ - v0 = ROTL(v0, 32); \ - v2 += v3; \ - v3 = ROTL(v3, 16); \ - v3 ^= v2; \ - v0 += v3; \ - v3 = ROTL(v3, 21); \ - v3 ^= v0; \ - v2 += v1; \ - v1 = ROTL(v1, 17); \ - v1 ^= v2; \ - v2 = ROTL(v2, 32); \ - } while (0) + do { \ + v0 += v1; \ + v1 = ROTL(v1, 13); \ + v1 ^= v0; \ + v0 = ROTL(v0, 32); \ + v2 += v3; \ + v3 = ROTL(v3, 16); \ + v3 ^= v2; \ + v0 += v3; \ + v3 = ROTL(v3, 21); \ + v3 ^= v0; \ + v2 += v1; \ + v1 = ROTL(v1, 17); \ + v1 ^= v2; \ + v2 = ROTL(v2, 32); \ + } while (0) #ifdef DEBUG_SIPHASH #include <stdio.h> #define TRACE \ - do { \ - printf("(%3zu) v0 %016" PRIx64 "\n", inlen, v0); \ - printf("(%3zu) v1 %016" PRIx64 "\n", inlen, v1); \ - printf("(%3zu) v2 %016" PRIx64 "\n", inlen, v2); \ - printf("(%3zu) v3 %016" PRIx64 "\n", inlen, v3); \ - } while (0) + do { \ + printf("(%3zu) v0 %016" PRIx64 "\n", inlen, v0); \ + printf("(%3zu) v1 %016" PRIx64 "\n", inlen, v1); \ + printf("(%3zu) v2 %016" PRIx64 "\n", inlen, v2); \ + printf("(%3zu) v3 %016" PRIx64 "\n", inlen, v3); \ + } while (0) #else #define TRACE #endif @@ -82,104 +76,104 @@ Computes a SipHash value *in: pointer to input data (read-only) inlen: input data length in bytes (any size_t value) - *k: pointer to the key data (read-only), must be 16 bytes + *k: pointer to the key data (read-only), must be 16 bytes *out: pointer to output data (write-only), outlen bytes must be allocated outlen: length of the output in bytes, must be 8 or 16 */ int siphash(const void *in, const size_t inlen, const void *k, uint8_t *out, const size_t outlen) { - const unsigned char *ni = (const unsigned char *)in; - const unsigned char *kk = (const unsigned char *)k; - - assert((outlen == 8) || (outlen == 16)); - uint64_t v0 = UINT64_C(0x736f6d6570736575); - uint64_t v1 = UINT64_C(0x646f72616e646f6d); - uint64_t v2 = UINT64_C(0x6c7967656e657261); - uint64_t v3 = UINT64_C(0x7465646279746573); - uint64_t k0 = U8TO64_LE(kk); - uint64_t k1 = U8TO64_LE(kk + 8); - uint64_t m; - int i; - const unsigned char *end = ni + inlen - (inlen % sizeof(uint64_t)); - const int left = inlen & 7; - uint64_t b = ((uint64_t)inlen) << 56; - v3 ^= k1; - v2 ^= k0; - v1 ^= k1; - v0 ^= k0; - - if (outlen == 16) - v1 ^= 0xee; - - for (; ni != end; ni += 8) { - m = U8TO64_LE(ni); - v3 ^= m; - - TRACE; - for (i = 0; i < cROUNDS; ++i) - SIPROUND; - - v0 ^= m; - } - - switch (left) { - case 7: - b |= ((uint64_t)ni[6]) << 48; - /* FALLTHRU */ - case 6: - b |= ((uint64_t)ni[5]) << 40; - /* FALLTHRU */ - case 5: - b |= ((uint64_t)ni[4]) << 32; - /* FALLTHRU */ - case 4: - b |= ((uint64_t)ni[3]) << 24; - /* FALLTHRU */ - case 3: - b |= ((uint64_t)ni[2]) << 16; - /* FALLTHRU */ - case 2: - b |= ((uint64_t)ni[1]) << 8; - /* FALLTHRU */ - case 1: - b |= ((uint64_t)ni[0]); - break; - case 0: - break; - } - - v3 ^= b; + const unsigned char *ni = (const unsigned char *)in; + const unsigned char *kk = (const unsigned char *)k; + + assert((outlen == 8) || (outlen == 16)); + uint64_t v0 = UINT64_C(0x736f6d6570736575); + uint64_t v1 = UINT64_C(0x646f72616e646f6d); + uint64_t v2 = UINT64_C(0x6c7967656e657261); + uint64_t v3 = UINT64_C(0x7465646279746573); + uint64_t k0 = U8TO64_LE(kk); + uint64_t k1 = U8TO64_LE(kk + 8); + uint64_t m; + int i; + const unsigned char *end = ni + inlen - (inlen % sizeof(uint64_t)); + const int left = inlen & 7; + uint64_t b = ((uint64_t)inlen) << 56; + v3 ^= k1; + v2 ^= k0; + v1 ^= k1; + v0 ^= k0; + + if (outlen == 16) + v1 ^= 0xee; + + for (; ni != end; ni += 8) { + m = U8TO64_LE(ni); + v3 ^= m; TRACE; for (i = 0; i < cROUNDS; ++i) - SIPROUND; - - v0 ^= b; - - if (outlen == 16) - v2 ^= 0xee; - else - v2 ^= 0xff; - - TRACE; - for (i = 0; i < dROUNDS; ++i) - SIPROUND; - - b = v0 ^ v1 ^ v2 ^ v3; - U64TO8_LE(out, b); - - if (outlen == 8) - return 0; + SIPROUND; + + v0 ^= m; + } + + switch (left) { + case 7: + b |= ((uint64_t)ni[6]) << 48; + /* FALLTHRU */ + case 6: + b |= ((uint64_t)ni[5]) << 40; + /* FALLTHRU */ + case 5: + b |= ((uint64_t)ni[4]) << 32; + /* FALLTHRU */ + case 4: + b |= ((uint64_t)ni[3]) << 24; + /* FALLTHRU */ + case 3: + b |= ((uint64_t)ni[2]) << 16; + /* FALLTHRU */ + case 2: + b |= ((uint64_t)ni[1]) << 8; + /* FALLTHRU */ + case 1: + b |= ((uint64_t)ni[0]); + break; + case 0: + break; + } + + v3 ^= b; + + TRACE; + for (i = 0; i < cROUNDS; ++i) + SIPROUND; + + v0 ^= b; + + if (outlen == 16) + v2 ^= 0xee; + else + v2 ^= 0xff; + + TRACE; + for (i = 0; i < dROUNDS; ++i) + SIPROUND; + + b = v0 ^ v1 ^ v2 ^ v3; + U64TO8_LE(out, b); + + if (outlen == 8) + return 0; - v1 ^= 0xdd; + v1 ^= 0xdd; - TRACE; - for (i = 0; i < dROUNDS; ++i) - SIPROUND; + TRACE; + for (i = 0; i < dROUNDS; ++i) + SIPROUND; - b = v0 ^ v1 ^ v2 ^ v3; - U64TO8_LE(out + 8, b); + b = v0 ^ v1 ^ v2 ^ v3; + U64TO8_LE(out + 8, b); - return 0; + return 0; } >From a1dbd8a893cf6dfedf9342fbaf07c6661c0a03a0 Mon Sep 17 00:00:00 2001 From: Ahmed Bougacha <ah...@bougacha.org> Date: Tue, 4 Jun 2024 12:45:37 -0700 Subject: [PATCH 2/3] [Support] Remove SipHash tracing support. --- llvm/lib/Support/SipHash.cpp | 18 ------------------ 1 file changed, 18 deletions(-) diff --git a/llvm/lib/Support/SipHash.cpp b/llvm/lib/Support/SipHash.cpp index f31023740011f..b7cc692b7d6b4 100644 --- a/llvm/lib/Support/SipHash.cpp +++ b/llvm/lib/Support/SipHash.cpp @@ -58,20 +58,6 @@ v2 = ROTL(v2, 32); \ } while (0) -#ifdef DEBUG_SIPHASH -#include <stdio.h> - -#define TRACE \ - do { \ - printf("(%3zu) v0 %016" PRIx64 "\n", inlen, v0); \ - printf("(%3zu) v1 %016" PRIx64 "\n", inlen, v1); \ - printf("(%3zu) v2 %016" PRIx64 "\n", inlen, v2); \ - printf("(%3zu) v3 %016" PRIx64 "\n", inlen, v3); \ - } while (0) -#else -#define TRACE -#endif - /* Computes a SipHash value *in: pointer to input data (read-only) @@ -110,7 +96,6 @@ int siphash(const void *in, const size_t inlen, const void *k, uint8_t *out, m = U8TO64_LE(ni); v3 ^= m; - TRACE; for (i = 0; i < cROUNDS; ++i) SIPROUND; @@ -145,7 +130,6 @@ int siphash(const void *in, const size_t inlen, const void *k, uint8_t *out, v3 ^= b; - TRACE; for (i = 0; i < cROUNDS; ++i) SIPROUND; @@ -156,7 +140,6 @@ int siphash(const void *in, const size_t inlen, const void *k, uint8_t *out, else v2 ^= 0xff; - TRACE; for (i = 0; i < dROUNDS; ++i) SIPROUND; @@ -168,7 +151,6 @@ int siphash(const void *in, const size_t inlen, const void *k, uint8_t *out, v1 ^= 0xdd; - TRACE; for (i = 0; i < dROUNDS; ++i) SIPROUND; >From 1d8561032aeb0df7030b5a69267410ecd58dd2fe Mon Sep 17 00:00:00 2001 From: Ahmed Bougacha <ah...@bougacha.org> Date: Tue, 4 Jun 2024 12:48:11 -0700 Subject: [PATCH 3/3] [Support] Integrate SipHash.cpp into libSupport. Start building it as part of the library, with some minor tweaks compared to the reference implementation: - templatize cROUNDS/dROUNDS, as well as 8B/16B result type - replace assert with static_assert - return the result directly, as uint64_t/uint128_t - remove big-endian support - use LLVM_FALLTHROUGH The siphash function itself isn't used yet, and will be in a follow-up commit. --- llvm/lib/Support/CMakeLists.txt | 4 +- llvm/lib/Support/SipHash.cpp | 67 +++++++++++---------------------- 2 files changed, 22 insertions(+), 49 deletions(-) diff --git a/llvm/lib/Support/CMakeLists.txt b/llvm/lib/Support/CMakeLists.txt index 7cc01a5399911..f5f8447d48d01 100644 --- a/llvm/lib/Support/CMakeLists.txt +++ b/llvm/lib/Support/CMakeLists.txt @@ -127,9 +127,6 @@ endif() add_subdirectory(BLAKE3) -# Temporarily ignore SipHash.cpp before we fully integrate it into LLVMSupport. -set(LLVM_OPTIONAL_SOURCES SipHash.cpp) - add_llvm_component_library(LLVMSupport ABIBreak.cpp AMDGPUMetadata.cpp @@ -226,6 +223,7 @@ add_llvm_component_library(LLVMSupport SHA1.cpp SHA256.cpp Signposts.cpp + SipHash.cpp SmallPtrSet.cpp SmallVector.cpp SourceMgr.cpp diff --git a/llvm/lib/Support/SipHash.cpp b/llvm/lib/Support/SipHash.cpp index b7cc692b7d6b4..8177b5359e8ed 100644 --- a/llvm/lib/Support/SipHash.cpp +++ b/llvm/lib/Support/SipHash.cpp @@ -6,34 +6,15 @@ // //===----------------------------------------------------------------------===// -#include "siphash.h" -#include <assert.h> -#include <stddef.h> -#include <stdint.h> +#include "llvm/Support/Compiler.h" +#include <cstdint> +#include <cstring> // Lightly adapted from the SipHash reference C implementation by // Jean-Philippe Aumasson and Daniel J. Bernstein. -/* default: SipHash-2-4 */ -#ifndef cROUNDS -#define cROUNDS 2 -#endif -#ifndef dROUNDS -#define dROUNDS 4 -#endif - #define ROTL(x, b) (uint64_t)(((x) << (b)) | ((x) >> (64 - (b)))) -#define U32TO8_LE(p, v) \ - (p)[0] = (uint8_t)((v)); \ - (p)[1] = (uint8_t)((v) >> 8); \ - (p)[2] = (uint8_t)((v) >> 16); \ - (p)[3] = (uint8_t)((v) >> 24); - -#define U64TO8_LE(p, v) \ - U32TO8_LE((p), (uint32_t)((v))); \ - U32TO8_LE((p) + 4, (uint32_t)((v) >> 32)); - #define U8TO64_LE(p) \ (((uint64_t)((p)[0])) | ((uint64_t)((p)[1]) << 8) | \ ((uint64_t)((p)[2]) << 16) | ((uint64_t)((p)[3]) << 24) | \ @@ -58,21 +39,15 @@ v2 = ROTL(v2, 32); \ } while (0) -/* - Computes a SipHash value - *in: pointer to input data (read-only) - inlen: input data length in bytes (any size_t value) - *k: pointer to the key data (read-only), must be 16 bytes - *out: pointer to output data (write-only), outlen bytes must be allocated - outlen: length of the output in bytes, must be 8 or 16 -*/ -int siphash(const void *in, const size_t inlen, const void *k, uint8_t *out, - const size_t outlen) { +template <int cROUNDS, int dROUNDS, class ResultTy> +static inline ResultTy siphash(const unsigned char *in, uint64_t inlen, + const unsigned char (&k)[16]) { const unsigned char *ni = (const unsigned char *)in; const unsigned char *kk = (const unsigned char *)k; - assert((outlen == 8) || (outlen == 16)); + static_assert(sizeof(ResultTy) == 8 || sizeof(ResultTy) == 16, + "result type should be uint64_t or uint128_t"); uint64_t v0 = UINT64_C(0x736f6d6570736575); uint64_t v1 = UINT64_C(0x646f72616e646f6d); uint64_t v2 = UINT64_C(0x6c7967656e657261); @@ -89,7 +64,7 @@ int siphash(const void *in, const size_t inlen, const void *k, uint8_t *out, v1 ^= k1; v0 ^= k0; - if (outlen == 16) + if (sizeof(ResultTy) == 16) v1 ^= 0xee; for (; ni != end; ni += 8) { @@ -105,22 +80,22 @@ int siphash(const void *in, const size_t inlen, const void *k, uint8_t *out, switch (left) { case 7: b |= ((uint64_t)ni[6]) << 48; - /* FALLTHRU */ + LLVM_FALLTHROUGH; case 6: b |= ((uint64_t)ni[5]) << 40; - /* FALLTHRU */ + LLVM_FALLTHROUGH; case 5: b |= ((uint64_t)ni[4]) << 32; - /* FALLTHRU */ + LLVM_FALLTHROUGH; case 4: b |= ((uint64_t)ni[3]) << 24; - /* FALLTHRU */ + LLVM_FALLTHROUGH; case 3: b |= ((uint64_t)ni[2]) << 16; - /* FALLTHRU */ + LLVM_FALLTHROUGH; case 2: b |= ((uint64_t)ni[1]) << 8; - /* FALLTHRU */ + LLVM_FALLTHROUGH; case 1: b |= ((uint64_t)ni[0]); break; @@ -135,7 +110,7 @@ int siphash(const void *in, const size_t inlen, const void *k, uint8_t *out, v0 ^= b; - if (outlen == 16) + if (sizeof(ResultTy) == 16) v2 ^= 0xee; else v2 ^= 0xff; @@ -144,10 +119,10 @@ int siphash(const void *in, const size_t inlen, const void *k, uint8_t *out, SIPROUND; b = v0 ^ v1 ^ v2 ^ v3; - U64TO8_LE(out, b); - if (outlen == 8) - return 0; + uint64_t firstHalf = b; + if (sizeof(ResultTy) == 8) + return firstHalf; v1 ^= 0xdd; @@ -155,7 +130,7 @@ int siphash(const void *in, const size_t inlen, const void *k, uint8_t *out, SIPROUND; b = v0 ^ v1 ^ v2 ^ v3; - U64TO8_LE(out + 8, b); + uint64_t secondHalf = b; - return 0; + return firstHalf | (ResultTy(secondHalf) << (sizeof(ResultTy) == 8 ? 0 : 64)); } _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
