347c5d6842
Hash.cpp uses llvm_unreachable but currently picks up ErrorHandling.h only transitively through xxhash.h -> ArrayRef.h -> Hashing.h.
53 lines
1.6 KiB
C++
53 lines
1.6 KiB
C++
//===- Hash.cpp - Hash functions ---------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements hash functions.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/Support/Hash.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Support/xxhash.h"
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using namespace llvm;
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KCFIHashAlgorithm llvm::parseKCFIHashAlgorithm(StringRef Name) {
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if (Name == "FNV-1a")
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return KCFIHashAlgorithm::FNV1a;
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// Default to xxHash64 for backward compatibility
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return KCFIHashAlgorithm::xxHash64;
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}
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StringRef llvm::stringifyKCFIHashAlgorithm(KCFIHashAlgorithm Algorithm) {
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switch (Algorithm) {
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case KCFIHashAlgorithm::xxHash64:
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return "xxHash64";
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case KCFIHashAlgorithm::FNV1a:
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return "FNV-1a";
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}
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llvm_unreachable("Unknown KCFI hash algorithm");
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}
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uint32_t llvm::getKCFITypeID(StringRef MangledTypeName,
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KCFIHashAlgorithm Algorithm) {
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switch (Algorithm) {
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case KCFIHashAlgorithm::xxHash64:
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// Use lower 32 bits of xxHash64
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return static_cast<uint32_t>(xxHash64(MangledTypeName));
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case KCFIHashAlgorithm::FNV1a:
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// FNV-1a hash (32-bit)
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uint32_t Hash = 2166136261u; // FNV offset basis
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for (unsigned char C : MangledTypeName) {
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Hash ^= C;
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Hash *= 16777619u; // FNV prime
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}
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return Hash;
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}
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llvm_unreachable("Unknown KCFI hash algorithm");
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}
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