tiny.simd.PhastBuildPlan

1pub const Plan = struct {2    num_keys: usize,3    payload_bytes: usize,4    configs: [max_config_count]family.Config,5    config_count: usize,6    max_num_slots: usize,7    max_num_buckets: usize,8    scratch_len: usize,9    seeds_len: usize,1011    const Self = @This();1213    pub fn inspect(num_keys: usize, payload_bytes: usize) family.PhastError!Self {14        if (num_keys == 0) {15            return .{16                .num_keys = 0,17                .payload_bytes = payload_bytes,18                .configs = @splat(.{}),19                .config_count = 0,20                .max_num_slots = 0,21                .max_num_buckets = 0,22                .scratch_len = 0,23                .seeds_len = 0,24            };25        }26        if (num_keys > std.math.maxInt(u32)) return error.CapacityExceeded;27        var configs: [max_config_count]family.Config = @splat(.{});28        const config_count = try enumerateConfigs(num_keys, configs[0..]);29        var max_num_slots: usize = 0;30        var max_num_buckets: usize = 0;31        for (configs[0..config_count]) |config| {32            _ = try config.allocatedBytes(payload_bytes);33            max_num_slots = @max(max_num_slots, config.num_slots);34            max_num_buckets = @max(max_num_buckets, config.numBuckets());35        }36        sortConfigs(configs[0..config_count], payload_bytes);37        return .{38            .num_keys = num_keys,39            .payload_bytes = payload_bytes,40            .configs = configs,41            .config_count = config_count,42            .max_num_slots = max_num_slots,43            .max_num_buckets = max_num_buckets,44            .scratch_len = try scratchLength(num_keys, max_num_slots, max_num_buckets),45            .seeds_len = family.seedWordLength(max_num_buckets),46        };47    }4849    pub fn build(50        self: Self,51        scratch: []u32,52        seed_words: []u32,53        keys: []const u32,54    ) family.PhastError!family.Data {55        try self.validateBuffers(scratch, seed_words, keys);56        if (self.num_keys == 0) return .{};57        var builder = try Builder.init(self, scratch, seed_words);58        try builder.validateDistinct(keys);59        const engine = random.AesCtrEngine.initDeterministic();60        for (self.configs[0..self.config_count], 0..) |config, config_index| {61            for (0..max_attempts) |attempt_index| {62                const stream = @as(u64, config.hash_key) + attempt_index;63                const hash_key: u32 = @truncate(engine.generate(stream, 0));64                if (!builder.maybeBuild(keys, config, hash_key)) continue;65                return builder.take(config_index, attempt_index);66            }67        }68        @memset(seed_words[0..self.seeds_len], 0);69        return error.BuildFailed;70    }7172    fn validateBuffers(73        self: Self,74        scratch: []u32,75        seed_words: []u32,76        keys: []const u32,77    ) family.PhastError!void {78        if (keys.len != self.num_keys) return error.PlanMismatch;79        if (scratch.len < self.scratch_len) return error.ScratchTooSmall;80        if (seed_words.len < self.seeds_len) return error.SeedsTooSmall;81        if (storageOverlaps(u32, scratch, u32, seed_words) or82            storageOverlaps(u32, scratch, u32, keys) or83            storageOverlaps(u32, seed_words, u32, keys))84        {85            return error.InputOutputOverlap;86        }87    }88};

1pub const PhastBuildPlan = phast.PhastBuildPlan;