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diff -rauN libcuckoo-0.3/tests/unit-tests/test_resize.cc libcuckoo-0.3-resize-unit-test-patch/tests/unit-tests/test_resize.cc
--- libcuckoo-0.3/tests/unit-tests/test_resize.cc 2020-03-25 15:39:43.000000000 +0100
+++ libcuckoo-0.3-resize-unit-test-patch/tests/unit-tests/test_resize.cc 2022-02-11 06:26:19.181932212 +0100
@@ -1,4 +1,5 @@
#include <array>
+#include <limits>
#include <catch.hpp>
@@ -45,15 +46,27 @@
REQUIRE(UnitTestInternalAccess::reserve_calc<IntIntTable>(
2500000 * slot_per_bucket) == 22);
- REQUIRE(UnitTestInternalAccess::reserve_calc<IntIntTable>(
- (1ULL << 31) * slot_per_bucket) == 31);
- REQUIRE(UnitTestInternalAccess::reserve_calc<IntIntTable>(
- ((1ULL << 31) + 1) * slot_per_bucket) == 32);
-
- REQUIRE(UnitTestInternalAccess::reserve_calc<IntIntTable>(
- (1ULL << 61) * slot_per_bucket) == 61);
- REQUIRE(UnitTestInternalAccess::reserve_calc<IntIntTable>(
- ((1ULL << 61) + 1) * slot_per_bucket) == 62);
+ // The maximum number of elements we can ask to reserve without incurring
+ // rounding error when computing a number of buckets is
+ // SIZE_T_MAX-slot_per_bucket(), which will come out to int_div(SIZE_T_MAX -
+ // 1, slot_per_bucket()) buckets.
+ const size_t max_buckets = (
+ std::numeric_limits<size_t>::max() - 1)/slot_per_bucket;
+ // Since the table is always sized in powers of two, our maximum hashpower
+ // comes out to max_hashpower = floor(log2(max_buckets)). We compute this in
+ // a numerically-stable fashion.
+ size_t max_hashpower = 0;
+ for (; (static_cast<size_t>(1) << (max_hashpower + 1)) <= max_buckets; ++max_hashpower);
+ // Test the boundary between max_hashpower-1 and max_hashpower.
+ const size_t max_elems_before_max_hashpower = (
+ static_cast<size_t>(1) << (max_hashpower - 1)) * slot_per_bucket;
+ REQUIRE(UnitTestInternalAccess::reserve_calc<IntIntTable>(
+ max_elems_before_max_hashpower) == (max_hashpower - 1));
+ REQUIRE(UnitTestInternalAccess::reserve_calc<IntIntTable>(
+ max_elems_before_max_hashpower + 1) == max_hashpower);
+ // Test the maximum number of elements.
+ const size_t max_elems = (static_cast<size_t>(1) << max_hashpower) * slot_per_bucket;
+ REQUIRE(UnitTestInternalAccess::reserve_calc<IntIntTable>(max_elems) == max_hashpower);
}
struct my_type {
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