v8/test/cctest/test-fast-dtoa.cc
Dan Elphick 44e73e0b78 Reland "[base] Move most of src/numbers into base"
This is a reland of 9701d4a420
with a small fix for some code landed in between the dry-run and
submission.

Original change's description:
> [base] Move most of src/numbers into base
>
> Moves all but conversions.*, hash-seed-inl.h and math-random.* into
> base, in preparation for moving the parts of conversions that don't
> access HeapObjects.
>
> Also moves uc16 and uc32 out of commons/globals.h into base/strings.h.
>
> Bug: v8:11917
> Change-Id: Ife359148bb0961a63833aff40d26331454b6afb6
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2979595
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Reviewed-by: Clemens Backes <clemensb@chromium.org>
> Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
> Auto-Submit: Dan Elphick <delphick@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#75354}

Bug: v8:11917
Change-Id: Ie1ec9032fe56646a7c7303185cecc70fce5694ae
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2982607
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75368}
2021-06-24 15:00:27 +00:00

295 lines
10 KiB
C++

// Copyright 2006-2008 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include <stdlib.h>
#include "src/base/numbers/diy-fp.h"
#include "src/base/numbers/double.h"
#include "src/base/numbers/fast-dtoa.h"
#include "src/base/platform/platform.h"
#include "src/init/v8.h"
#include "test/cctest/cctest.h"
#include "test/cctest/gay-precision.h"
#include "test/cctest/gay-shortest.h"
namespace v8 {
namespace base {
namespace test_fast_dtoa {
static const int kBufferSize = 100;
// Removes trailing '0' digits (modifies {representation}). Can create an empty
// string if all digits are 0.
static void TrimRepresentation(char* representation) {
size_t len = strlen(representation);
while (len > 0 && representation[len - 1] == '0') --len;
representation[len] = '\0';
}
TEST(FastDtoaShortestVariousDoubles) {
char buffer_container[kBufferSize];
Vector<char> buffer(buffer_container, kBufferSize);
int length;
int point;
int status;
double min_double = 5e-324;
status = FastDtoa(min_double, FAST_DTOA_SHORTEST, 0,
buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("5", buffer.begin()));
CHECK_EQ(-323, point);
double max_double = 1.7976931348623157e308;
status = FastDtoa(max_double, FAST_DTOA_SHORTEST, 0,
buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("17976931348623157", buffer.begin()));
CHECK_EQ(309, point);
status = FastDtoa(4294967272.0, FAST_DTOA_SHORTEST, 0,
buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("4294967272", buffer.begin()));
CHECK_EQ(10, point);
status = FastDtoa(4.1855804968213567e298, FAST_DTOA_SHORTEST, 0,
buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("4185580496821357", buffer.begin()));
CHECK_EQ(299, point);
status = FastDtoa(5.5626846462680035e-309, FAST_DTOA_SHORTEST, 0,
buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("5562684646268003", buffer.begin()));
CHECK_EQ(-308, point);
status = FastDtoa(2147483648.0, FAST_DTOA_SHORTEST, 0,
buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("2147483648", buffer.begin()));
CHECK_EQ(10, point);
status = FastDtoa(3.5844466002796428e+298, FAST_DTOA_SHORTEST, 0,
buffer, &length, &point);
if (status) { // Not all FastDtoa variants manage to compute this number.
CHECK_EQ(0, strcmp("35844466002796428", buffer.begin()));
CHECK_EQ(299, point);
}
uint64_t smallest_normal64 = 0x0010'0000'0000'0000;
double v = Double(smallest_normal64).value();
status = FastDtoa(v, FAST_DTOA_SHORTEST, 0, buffer, &length, &point);
if (status) {
CHECK_EQ(0, strcmp("22250738585072014", buffer.begin()));
CHECK_EQ(-307, point);
}
uint64_t largest_denormal64 = 0x000F'FFFF'FFFF'FFFF;
v = Double(largest_denormal64).value();
status = FastDtoa(v, FAST_DTOA_SHORTEST, 0, buffer, &length, &point);
if (status) {
CHECK_EQ(0, strcmp("2225073858507201", buffer.begin()));
CHECK_EQ(-307, point);
}
}
TEST(FastDtoaPrecisionVariousDoubles) {
char buffer_container[kBufferSize];
Vector<char> buffer(buffer_container, kBufferSize);
int length;
int point;
int status;
status = FastDtoa(1.0, FAST_DTOA_PRECISION, 3, buffer, &length, &point);
CHECK(status);
CHECK_GE(3, length);
TrimRepresentation(buffer.begin());
CHECK_EQ(0, strcmp("1", buffer.begin()));
CHECK_EQ(1, point);
status = FastDtoa(1.5, FAST_DTOA_PRECISION, 10, buffer, &length, &point);
if (status) {
CHECK_GE(10, length);
TrimRepresentation(buffer.begin());
CHECK_EQ(0, strcmp("15", buffer.begin()));
CHECK_EQ(1, point);
}
double min_double = 5e-324;
status = FastDtoa(min_double, FAST_DTOA_PRECISION, 5,
buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("49407", buffer.begin()));
CHECK_EQ(-323, point);
double max_double = 1.7976931348623157e308;
status = FastDtoa(max_double, FAST_DTOA_PRECISION, 7,
buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("1797693", buffer.begin()));
CHECK_EQ(309, point);
status = FastDtoa(4294967272.0, FAST_DTOA_PRECISION, 14,
buffer, &length, &point);
if (status) {
CHECK_GE(14, length);
TrimRepresentation(buffer.begin());
CHECK_EQ(0, strcmp("4294967272", buffer.begin()));
CHECK_EQ(10, point);
}
status = FastDtoa(4.1855804968213567e298, FAST_DTOA_PRECISION, 17,
buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("41855804968213567", buffer.begin()));
CHECK_EQ(299, point);
status = FastDtoa(5.5626846462680035e-309, FAST_DTOA_PRECISION, 1,
buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("6", buffer.begin()));
CHECK_EQ(-308, point);
status = FastDtoa(2147483648.0, FAST_DTOA_PRECISION, 5,
buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("21475", buffer.begin()));
CHECK_EQ(10, point);
status = FastDtoa(3.5844466002796428e+298, FAST_DTOA_PRECISION, 10,
buffer, &length, &point);
CHECK(status);
CHECK_GE(10, length);
TrimRepresentation(buffer.begin());
CHECK_EQ(0, strcmp("35844466", buffer.begin()));
CHECK_EQ(299, point);
uint64_t smallest_normal64 = 0x0010'0000'0000'0000;
double v = Double(smallest_normal64).value();
status = FastDtoa(v, FAST_DTOA_PRECISION, 17, buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("22250738585072014", buffer.begin()));
CHECK_EQ(-307, point);
uint64_t largest_denormal64 = 0x000F'FFFF'FFFF'FFFF;
v = Double(largest_denormal64).value();
status = FastDtoa(v, FAST_DTOA_PRECISION, 17, buffer, &length, &point);
CHECK(status);
CHECK_GE(20, length);
TrimRepresentation(buffer.begin());
CHECK_EQ(0, strcmp("22250738585072009", buffer.begin()));
CHECK_EQ(-307, point);
v = 3.3161339052167390562200598e-237;
status = FastDtoa(v, FAST_DTOA_PRECISION, 18, buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("331613390521673906", buffer.begin()));
CHECK_EQ(-236, point);
v = 7.9885183916008099497815232e+191;
status = FastDtoa(v, FAST_DTOA_PRECISION, 4, buffer, &length, &point);
CHECK(status);
CHECK_EQ(0, strcmp("7989", buffer.begin()));
CHECK_EQ(192, point);
}
TEST(FastDtoaGayShortest) {
char buffer_container[kBufferSize];
Vector<char> buffer(buffer_container, kBufferSize);
bool status;
int length;
int point;
int succeeded = 0;
int total = 0;
bool needed_max_length = false;
Vector<const PrecomputedShortest> precomputed =
PrecomputedShortestRepresentations();
for (int i = 0; i < precomputed.length(); ++i) {
const PrecomputedShortest current_test = precomputed[i];
total++;
double v = current_test.v;
status = FastDtoa(v, FAST_DTOA_SHORTEST, 0, buffer, &length, &point);
CHECK_GE(kFastDtoaMaximalLength, length);
if (!status) continue;
if (length == kFastDtoaMaximalLength) needed_max_length = true;
succeeded++;
CHECK_EQ(current_test.decimal_point, point);
CHECK_EQ(0, strcmp(current_test.representation, buffer.begin()));
}
CHECK_GT(succeeded*1.0/total, 0.99);
CHECK(needed_max_length);
}
TEST(FastDtoaGayPrecision) {
char buffer_container[kBufferSize];
Vector<char> buffer(buffer_container, kBufferSize);
bool status;
int length;
int point;
int succeeded = 0;
int total = 0;
// Count separately for entries with less than 15 requested digits.
int succeeded_15 = 0;
int total_15 = 0;
Vector<const PrecomputedPrecision> precomputed =
PrecomputedPrecisionRepresentations();
for (int i = 0; i < precomputed.length(); ++i) {
const PrecomputedPrecision current_test = precomputed[i];
double v = current_test.v;
int number_digits = current_test.number_digits;
total++;
if (number_digits <= 15) total_15++;
status = FastDtoa(v, FAST_DTOA_PRECISION, number_digits,
buffer, &length, &point);
CHECK_GE(number_digits, length);
if (!status) continue;
succeeded++;
if (number_digits <= 15) succeeded_15++;
TrimRepresentation(buffer.begin());
CHECK_EQ(current_test.decimal_point, point);
CHECK_EQ(0, strcmp(current_test.representation, buffer.begin()));
}
// The precomputed numbers contain many entries with many requested
// digits. These have a high failure rate and we therefore expect a lower
// success rate than for the shortest representation.
CHECK_GT(succeeded*1.0/total, 0.85);
// However with less than 15 digits almost the algorithm should almost always
// succeed.
CHECK_GT(succeeded_15*1.0/total_15, 0.9999);
}
} // namespace test_fast_dtoa
} // namespace base
} // namespace v8