libc/test/src/stdlib/strtold_test.cpp

   1 //===-- Unittests for strtold ---------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "src/__support/FPUtil/FPBits.h"
  10 #include "src/__support/UInt128.h"
  11 #include "src/errno/libc_errno.h"
  12 #include "src/stdlib/strtold.h"
  13
  14 #include "test/UnitTest/Test.h"
  15
  16 #include <limits.h>
  17 #include <stddef.h>
  18
  19 #if defined(LONG_DOUBLE_IS_DOUBLE)
  20 #define SELECT_CONST(val, _, __) val
  21 #elif defined(SPECIAL_X86_LONG_DOUBLE)
  22 #define SELECT_CONST(_, val, __) val
  23 #else
  24 #define SELECT_CONST(_, __, val) val
  25 #endif
  26
  27 class LlvmLibcStrToLDTest : public LIBC_NAMESPACE::testing::Test {
  28 public:
  29 #if defined(LONG_DOUBLE_IS_DOUBLE)
  30   void run_test(const char *inputString, const ptrdiff_t expectedStrLen,
  31                 const uint64_t expectedRawData, const int expectedErrno = 0)
  32 #else
  33   void run_test(const char *inputString, const ptrdiff_t expectedStrLen,
  34                 const UInt128 expectedRawData, const int expectedErrno = 0)
  35 #endif
  36   {
  37     // expectedRawData64 is the expected long double result as a uint64_t,
  38     // organized according to the IEEE754 double precision format:
  39     //
  40     // +-- 1 Sign Bit                        +-- 52 Mantissa bits
  41     // |                                     |
  42     // |           +-------------------------+------------------------+
  43     // |           |                                                  |
  44     // SEEEEEEEEEEEMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
  45     //  |         |
  46     //  +----+----+
  47     //       |
  48     //       +-- 11 Exponent Bits
  49
  50     // expectedRawData80 is the expected long double result as a UInt128,
  51     // organized according to the x86 extended precision format:
  52     //
  53     // +-- 1 Sign Bit
  54     // |
  55     // |               +-- 1 Integer part bit (1 unless this is a subnormal)
  56     // |               |
  57     // SEEEEEEEEEEEEEEEIMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM...M
  58     //  |             | |                                                      |
  59     //  +------+------+ +---------------------------+--------------------------+
  60     //         |                                    |
  61     //         +-- 15 Exponent Bits                 +-- 63 Mantissa bits
  62
  63     // expectedRawData128 is the expected long double result as a UInt128,
  64     // organized according to IEEE754 quadruple precision format:
  65     //
  66     // +-- 1 Sign Bit                               +-- 112 Mantissa bits
  67     // |                                            |
  68     // |               +----------------------------+--------------------------+
  69     // |               |                                                       |
  70     // SEEEEEEEEEEEEEEEMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM...M
  71     //  |             |
  72     //  +------+------+
  73     //         |
  74     //         +-- 15 Exponent Bits
  75     char *str_end = nullptr;
  76
  77     LIBC_NAMESPACE::fputil::FPBits<long double> expected_fp =
  78         LIBC_NAMESPACE::fputil::FPBits<long double>(expectedRawData);
  79     const int expected_errno = expectedErrno;
  80
  81     libc_errno = 0;
  82     long double result = LIBC_NAMESPACE::strtold(inputString, &str_end);
  83
  84     LIBC_NAMESPACE::fputil::FPBits<long double> actual_fp =
  85         LIBC_NAMESPACE::fputil::FPBits<long double>();
  86     actual_fp = LIBC_NAMESPACE::fputil::FPBits<long double>(result);
  87
  88     EXPECT_EQ(str_end - inputString, expectedStrLen);
  89
  90     EXPECT_EQ(actual_fp.bits, expected_fp.bits);
  91     EXPECT_EQ(actual_fp.get_sign(), expected_fp.get_sign());
  92     EXPECT_EQ(actual_fp.get_exponent(), expected_fp.get_exponent());
  93     EXPECT_EQ(actual_fp.get_mantissa(), expected_fp.get_mantissa());
  94     EXPECT_EQ(libc_errno, expected_errno);
  95   }
  96 };
  97
  98 TEST_F(LlvmLibcStrToLDTest, SimpleTest) {
  99   run_test("123", 3,
 100            SELECT_CONST(uint64_t(0x405ec00000000000),
 101                         UInt128(0x4005f60000) << 40,
 102                         UInt128(0x4005ec0000000000) << 64));
 103
 104   // This should fail on Eisel-Lemire, forcing a fallback to simple decimal
 105   // conversion.
 106   run_test("12345678901234549760", 20,
 107            SELECT_CONST(uint64_t(0x43e56a95319d63d8),
 108                         (UInt128(0x403eab54a9) << 40) + UInt128(0x8ceb1ec400),
 109                         (UInt128(0x403e56a95319d63d) << 64) +
 110                             UInt128(0x8800000000000000)));
 111
 112   // Found while looking for difficult test cases here:
 113   // https://github.com/nigeltao/parse-number-fxx-test-data/blob/main/more-test-cases/golang-org-issue-36657.txt
 114   run_test("1090544144181609348835077142190", 31,
 115            SELECT_CONST(uint64_t(0x462b8779f2474dfb),
 116                         (UInt128(0x4062dc3bcf) << 40) + UInt128(0x923a6fd402),
 117                         (UInt128(0x4062b8779f2474df) << 64) +
 118                             UInt128(0xa804bfd8c6d5c000)));
 119
 120   run_test("0x123", 5,
 121            SELECT_CONST(uint64_t(0x4072300000000000),
 122                         (UInt128(0x4007918000) << 40),
 123                         (UInt128(0x4007230000000000) << 64)));
 124 }
 125
 126 // These are tests that have caused problems for doubles in the past.
 127 TEST_F(LlvmLibcStrToLDTest, Float64SpecificFailures) {
 128   run_test("3E70000000000000", 16,
 129            SELECT_CONST(uint64_t(0x7FF0000000000000),
 130                         (UInt128(0x7fff800000) << 40),
 131                         (UInt128(0x7fff000000000000) << 64)),
 132            ERANGE);
 133   run_test("358416272e-33", 13,
 134            SELECT_CONST(uint64_t(0x3adbbb2a68c9d0b9),
 135                         (UInt128(0x3fadddd953) << 40) + UInt128(0x464e85c400),
 136                         (UInt128(0x3fadbbb2a68c9d0b) << 64) +
 137                             UInt128(0x8800e7969e1c5fc8)));
 138   run_test("2.16656806400000023841857910156251e9", 36,
 139            SELECT_CONST(uint64_t(0x41e0246690000001),
 140                         (UInt128(0x401e812334) << 40) + UInt128(0x8000000400),
 141                         (UInt128(0x401e024669000000) << 64) +
 142                             UInt128(0x800000000000018)));
 143   run_test("27949676547093071875", 20,
 144            SELECT_CONST(uint64_t(0x43f83e132bc608c9),
 145                         (UInt128(0x403fc1f099) << 40) + UInt128(0x5e30464402),
 146                         (UInt128(0x403f83e132bc608c) << 64) +
 147                             UInt128(0x8803000000000000)));
 148 }
 149
 150 TEST_F(LlvmLibcStrToLDTest, Float80SpecificFailures) {
 151   run_test("7777777777777777777777777777777777777777777777777777777777777777777"
 152            "777777777777777777777777777777777",
 153            100,
 154            SELECT_CONST(uint64_t(0x54ac729b8fcaf734),
 155                         (UInt128(0x414ae394dc) << 40) + UInt128(0x7e57b9a0c2),
 156                         (UInt128(0x414ac729b8fcaf73) << 64) +
 157                             UInt128(0x4184a3d793224129)));
 158 }
 159
 160 TEST_F(LlvmLibcStrToLDTest, MaxSizeNumbers) {
 161   run_test("1.1897314953572317650e4932", 26,
 162            SELECT_CONST(uint64_t(0x7FF0000000000000),
 163                         (UInt128(0x7ffeffffff) << 40) + UInt128(0xffffffffff),
 164                         (UInt128(0x7ffeffffffffffff) << 64) +
 165                             UInt128(0xfffd57322e3f8675)),
 166            SELECT_CONST(ERANGE, 0, 0));
 167   run_test("1.18973149535723176508e4932", 27,
 168            SELECT_CONST(uint64_t(0x7FF0000000000000),
 169                         (UInt128(0x7fff800000) << 40),
 170                         (UInt128(0x7ffeffffffffffff) << 64) +
 171                             UInt128(0xffffd2478338036c)),
 172            SELECT_CONST(ERANGE, ERANGE, 0));
 173 }
 174
 175 // These tests check subnormal behavior for 80 bit and 128 bit floats. They will
 176 // be too small for 64 bit floats.
 177 TEST_F(LlvmLibcStrToLDTest, SubnormalTests) {
 178   run_test("1e-4950", 7,
 179            SELECT_CONST(uint64_t(0), (UInt128(0x00000000000000000003)),
 180                         (UInt128(0x000000000000000000057c9647e1a018))),
 181            ERANGE);
 182   run_test("1.89e-4951", 10,
 183            SELECT_CONST(uint64_t(0), (UInt128(0x00000000000000000001)),
 184                         (UInt128(0x0000000000000000000109778a006738))),
 185            ERANGE);
 186   run_test("4e-4966", 7,
 187            SELECT_CONST(uint64_t(0), (UInt128(0)),
 188                         (UInt128(0x00000000000000000000000000000001))),
 189            ERANGE);
 190 }
 191
 192 TEST_F(LlvmLibcStrToLDTest, SmallNormalTests) {
 193   run_test("3.37e-4932", 10,
 194            SELECT_CONST(
 195                uint64_t(0), (UInt128(0x1804cf7) << 40) + UInt128(0x908850712),
 196                (UInt128(0x10099ee12110a) << 64) + UInt128(0xe24b75c0f50dc0c)),
 197            SELECT_CONST(ERANGE, 0, 0));
 198 }
 199
 200 TEST_F(LlvmLibcStrToLDTest, ComplexHexadecimalTests) {
 201   run_test("0x1p16383", 9,
 202            SELECT_CONST(0x7ff0000000000000, (UInt128(0x7ffe800000) << 40),
 203                         (UInt128(0x7ffe000000000000) << 64)),
 204            SELECT_CONST(ERANGE, 0, 0));
 205   run_test("0x123456789abcdef", 17,
 206            SELECT_CONST(0x43723456789abcdf,
 207                         (UInt128(0x403791a2b3) << 40) + UInt128(0xc4d5e6f780),
 208                         (UInt128(0x403723456789abcd) << 64) +
 209                             UInt128(0xef00000000000000)));
 210   run_test("0x123456789abcdef0123456789ABCDEF", 33,
 211            SELECT_CONST(0x47723456789abcdf,
 212                         (UInt128(0x407791a2b3) << 40) + UInt128(0xc4d5e6f781),
 213                         (UInt128(0x407723456789abcd) << 64) +
 214                             UInt128(0xef0123456789abce)));
 215 }
 216
 217 TEST_F(LlvmLibcStrToLDTest, InfTests) {
 218   run_test("INF", 3,
 219            SELECT_CONST(0x7ff0000000000000, (UInt128(0x7fff800000) << 40),
 220                         (UInt128(0x7fff000000000000) << 64)));
 221   run_test("INFinity", 8,
 222            SELECT_CONST(0x7ff0000000000000, (UInt128(0x7fff800000) << 40),
 223                         (UInt128(0x7fff000000000000) << 64)));
 224   run_test("-inf", 4,
 225            SELECT_CONST(0xfff0000000000000, (UInt128(0xffff800000) << 40),
 226                         (UInt128(0xffff000000000000) << 64)));
 227 }
 228
 229 TEST_F(LlvmLibcStrToLDTest, NaNTests) {
 230   run_test("NaN", 3,
 231            SELECT_CONST(0x7ff8000000000000, (UInt128(0x7fffc00000) << 40),
 232                         (UInt128(0x7fff800000000000) << 64)));
 233   run_test("-nAn", 4,
 234            SELECT_CONST(0xfff8000000000000, (UInt128(0xffffc00000) << 40),
 235                         (UInt128(0xffff800000000000) << 64)));
 236   run_test("NaN()", 5,
 237            SELECT_CONST(0x7ff8000000000000, (UInt128(0x7fffc00000) << 40),
 238                         (UInt128(0x7fff800000000000) << 64)));
 239   run_test("NaN(1234)", 9,
 240            SELECT_CONST(0x7ff80000000004d2,
 241                         (UInt128(0x7fffc00000) << 40) + UInt128(0x4d2),
 242                         (UInt128(0x7fff800000000000) << 64) + UInt128(0x4d2)));
 243   run_test("NaN(0xffffffffffff)", 19,
 244            SELECT_CONST(0x7ff8ffffffffffff,
 245                         (UInt128(0x7fffc000ff) << 40) + UInt128(0xffffffffff),
 246                         (UInt128(0x7fff800000000000) << 64) +
 247                             UInt128(0xffffffffffff)));
 248   run_test("NaN(0xfffffffffffff)", 20,
 249            SELECT_CONST(0x7fffffffffffffff,
 250                         (UInt128(0x7fffc00fff) << 40) + UInt128(0xffffffffff),
 251                         (UInt128(0x7fff800000000000) << 64) +
 252                             UInt128(0xfffffffffffff)));
 253   run_test("NaN(0xffffffffffffffff)", 23,
 254            SELECT_CONST(0x7fffffffffffffff,
 255                         (UInt128(0x7fffffffff) << 40) + UInt128(0xffffffffff),
 256                         (UInt128(0x7fff800000000000) << 64) +
 257                             UInt128(0xffffffffffffffff)));
 258   run_test("NaN( 1234)", 3,
 259            SELECT_CONST(0x7ff8000000000000, (UInt128(0x7fffc00000) << 40),
 260                         (UInt128(0x7fff800000000000) << 64)));
 261 }