source: src/Concurrency/MutexFuncHash.hpp@ c9d36b1

//
// Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
//
// MutexFuncHash.hpp -- Hash utility for mutex function identity.
//
// Author           : Matthew Au-Yeung
// Created On       : Tue Jan 28 2026
//

#pragma once

#include <cstdint>
#include <string>

#include "AST/Decl.hpp"
#include "AST/Expr.hpp"
#include "AST/Type.hpp"
#include "SymTab/Mangler.hpp"

namespace Concurrency {

// FNV-1a hash of a function declaration's mangled name.
// Used to identify mutex functions across translation units,
// since function pointers may differ for static inline functions.
static inline uint64_t hashMangle( const ast::DeclWithType * decl ) {
        std::string name = Mangle::mangle( decl );
        uint64_t hash = 14695981039346656037ULL; // FNV offset basis
        for ( char c : name ) {
                hash ^= static_cast<uint64_t>( c );
                hash *= 1099511628211ULL; // FNV prime
        }
        return hash;
}

// Create a ConstantExpr for the hash with proper ULL suffix to avoid
// C compiler warnings about large unsigned constants.
static inline ast::ConstantExpr * hashMangleExpr(
                const CodeLocation & location, const ast::DeclWithType * decl ) {
        uint64_t hash = hashMangle( decl );
        return new ast::ConstantExpr{
                location,
                new ast::BasicType{ ast::BasicKind::LongLongUnsignedInt },
                std::to_string( hash ) + "ull",
                (unsigned long long)hash };
}

} // namespace Concurrency