From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-x42f.google.com (mail-wr1-x42f.google.com [IPv6:2a00:1450:4864:20::42f]) by sourceware.org (Postfix) with ESMTPS id 9C4A4384B806 for ; Wed, 26 Oct 2022 08:16:01 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 9C4A4384B806 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=embecosm.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=embecosm.com Received: by mail-wr1-x42f.google.com with SMTP id o4so16815718wrq.6 for ; Wed, 26 Oct 2022 01:16:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=embecosm.com; s=google; h=content-transfer-encoding:mime-version:reply-to:references :in-reply-to:message-id:date:subject:cc:to:from:from:to:cc:subject :date:message-id:reply-to; bh=5jfu0YJHbPc/EzQaSa6lSHgLzaq8oBe/JuPgiOxojzA=; b=FeWtJ9mGcW0Y150/u0oNQHkOd630e3qImX0wUpQSkykl92HKsnvd3ExZU7Tp6zYkOW AN8q0JxWQjnuiYxSZhdLAjmLYxYCyj4idIw7NA4iky91LjOZKqlW/AqlReg3LAMqETs/ 6844sTqWocisoZQwUIyrwaUWL2G0GiZ68fVA1q6v3rvVm3VVbiFYXmyyPoq9uapW3ahh PYk+r6lN+NH19Ze8Nm3IPMuXF1MzYJt7+fEvQ6OXZwCJ6wWXce2h3GQLwzx69aBxC0n9 CtsiD3B17Vb/Ogylg5DkZu50MfYE+xYfcWlHVzYs0HEWQMPvx1olSJterGJAdKBBKCbC lpAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:reply-to:references :in-reply-to:message-id:date:subject:cc:to:from:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=5jfu0YJHbPc/EzQaSa6lSHgLzaq8oBe/JuPgiOxojzA=; b=ObL4IFKy9BGZRy318zfH+YRi7KuhrC6FVkL8YY9+LhHIg3BpK3oNA5ln5W4jateHnO J4mEMmuYWKpIr0b1QD3OJAURpIvNrVRsh9jqhlNX/6E4+93zT3dSi9QhAGdh6Nwb/H+d i3Y4/xna3EoEVBM8UDF//TjKOlmkarOyNujj1s3oDyqGuktlRHz8ReayyJv8w6T0L32k csw2usIlHykoSfyl7UPwsZUtgL25picKBd4wC1Y+7z3TYjWDDrKx5W6e7sYiJiOom3et Aa+3x9VfG1EDaq6wAsee1uu2957aHjmmEqK82fZ45T64H4FrI4l3d7m4L14M5vY/LlI3 ZVbQ== X-Gm-Message-State: ACrzQf1C+ma6EYvR0v6V8wjFIGQq55NesZjMc2+G/LE9HOIp3Ztz6aDS dyRGu8/8xb+G2e+8JPoWQ/YIiGDgYIr7Ea53Kg== X-Google-Smtp-Source: AMsMyM6ybbT7vVly0he/pA7Tq3xBoSMcClHDG/zoi9k7FItpih1mxBsTaZdOjGclLksOlygIOU+EZw== X-Received: by 2002:a5d:64a4:0:b0:22f:8ff1:e0d5 with SMTP id m4-20020a5d64a4000000b0022f8ff1e0d5mr28072136wrp.354.1666772150027; Wed, 26 Oct 2022 01:15:50 -0700 (PDT) Received: from platypus.lan ([2001:861:5e4c:3bb0:6424:328a:1734:3249]) by smtp.googlemail.com with ESMTPSA id q16-20020a05600c46d000b003c6f426467fsm1134310wmo.40.2022.10.26.01.15.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 26 Oct 2022 01:15:49 -0700 (PDT) From: arthur.cohen@embecosm.com To: gcc-patches@gcc.gnu.org Cc: gcc-rust@gcc.gnu.org Subject: [PATCH Rust front-end v3 21/46] gccrs: Add port of FNV hash used during legacy symbol mangling Date: Wed, 26 Oct 2022 10:17:46 +0200 Message-Id: <20221026081811.602573-22-arthur.cohen@embecosm.com> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20221026081811.602573-1-arthur.cohen@embecosm.com> References: <20221026081811.602573-1-arthur.cohen@embecosm.com> Reply-To: arthur.cohen@embecosm.com MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-13.8 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,GIT_PATCH_0,KAM_SHORT,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,TXREP autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: From: Philip Herron This hash was ported from the go runime as we needed a hash for the legacy symbol mangling system. Which means all symbols in Rust contain a hash of some metadata for uniqueness on generic functions. --- gcc/rust/util/fnv-hash.h | 95 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+) create mode 100644 gcc/rust/util/fnv-hash.h diff --git a/gcc/rust/util/fnv-hash.h b/gcc/rust/util/fnv-hash.h new file mode 100644 index 00000000000..78e54c99411 --- /dev/null +++ b/gcc/rust/util/fnv-hash.h @@ -0,0 +1,95 @@ +// Copyright (C) 2020-2022 Free Software Foundation, Inc. + +// This file is part of GCC. + +// GCC is free software; you can redistribute it and/or modify it under +// the terms of the GNU General Public License as published by the Free +// Software Foundation; either version 3, or (at your option) any later +// version. + +// GCC is distributed in the hope that 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 GCC; see the file COPYING3. If not see +// . + +#ifndef RUST_FNV_HASH_H +#define RUST_FNV_HASH_H + +namespace Rust { +namespace Hash { + +const uint64_t offset128Lower = 0x62b821756295c58d; +const uint64_t offset128Higher = 0x6c62272e07bb0142; +const uint64_t prime128Lower = 0x13b; +const uint64_t prime128Shift = 24; + +// ported from https://github.com/golang/go/blob/master/src/hash/fnv/fnv.go +class FNV128 +{ +public: + FNV128 () { reset (); } + + void reset () + { + buf[0] = offset128Higher; + buf[1] = offset128Lower; + } + + void write (const unsigned char *in, size_t len) + { + for (size_t i = 0; i < len; i++) + { + unsigned char c = in[i]; + + // https://stackoverflow.com/questions/28868367/getting-the-high-part-of-64-bit-integer-multiplication + uint64_t a = prime128Lower; + uint64_t b = buf[1]; + + uint64_t a_lo = (uint32_t) a; + uint64_t a_hi = a >> 32; + uint64_t b_lo = (uint32_t) b; + uint64_t b_hi = b >> 32; + + uint64_t a_x_b_hi = a_hi * b_hi; + uint64_t a_x_b_mid = a_hi * b_lo; + uint64_t b_x_a_mid = b_hi * a_lo; + uint64_t a_x_b_lo = a_lo * b_lo; + + uint64_t carry_bit + = ((uint64_t) (uint32_t) a_x_b_mid + (uint64_t) (uint32_t) b_x_a_mid + + (a_x_b_lo >> 32)) + >> 32; + + uint64_t multhi + = a_x_b_hi + (a_x_b_mid >> 32) + (b_x_a_mid >> 32) + carry_bit; + + uint64_t s0 = multhi; // high + uint64_t s1 = prime128Lower * buf[1]; // low + + s0 += buf[1] << (prime128Shift + prime128Lower * buf[0]); + + // Update the values + buf[1] = s1; + buf[0] = s0; + buf[1] ^= (uint64_t) c; + } + } + + void sum (uint64_t *hi, uint64_t *lo) const + { + *hi = buf[0]; + *lo = buf[1]; + } + +private: + uint64_t buf[2]; +}; + +} // namespace Hash +} // namespace Rust + +#endif // RUST_FNV_HASH_H -- 2.37.2