50 changes: 37 additions & 13 deletions libc/test/src/math/exp2f_test.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -39,7 +39,7 @@ TEST(LlvmLibcExp2fTest, SpecialNumbers) {
EXPECT_MATH_ERRNO(0);
}

TEST(LlvmLibcExpfTest, Overflow) {
TEST(LlvmLibcExp2fTest, Overflow) {
errno = 0;
EXPECT_FP_EQ(inf, __llvm_libc::exp2f(float(FPBits(0x7f7fffffU))));
EXPECT_MATH_ERRNO(ERANGE);
Expand All @@ -53,50 +53,73 @@ TEST(LlvmLibcExpfTest, Overflow) {

// Test with inputs which are the borders of underflow/overflow but still
// produce valid results without setting errno.
TEST(LlvmLibcExpfTest, Borderline) {
TEST(LlvmLibcExp2fTest, Borderline) {
float x;

errno = 0;
x = float(FPBits(0x42fa0001U));
EXPECT_MPFR_MATCH(mpfr::Operation::Exp2, x, __llvm_libc::exp2f(x), 1.0);
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
__llvm_libc::exp2f(x), 0.5);
EXPECT_MATH_ERRNO(0);

x = float(FPBits(0x42ffffffU));
EXPECT_MPFR_MATCH(mpfr::Operation::Exp2, x, __llvm_libc::exp2f(x), 1.0);
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
__llvm_libc::exp2f(x), 0.5);
EXPECT_MATH_ERRNO(0);

x = float(FPBits(0xc2fa0001U));
EXPECT_MPFR_MATCH(mpfr::Operation::Exp2, x, __llvm_libc::exp2f(x), 1.0);
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
__llvm_libc::exp2f(x), 0.5);
EXPECT_MATH_ERRNO(0);

x = float(FPBits(0xc2fc0000U));
EXPECT_MPFR_MATCH(mpfr::Operation::Exp2, x, __llvm_libc::exp2f(x), 1.0);
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
__llvm_libc::exp2f(x), 0.5);
EXPECT_MATH_ERRNO(0);

x = float(FPBits(0xc2fc0001U));
EXPECT_MPFR_MATCH(mpfr::Operation::Exp2, x, __llvm_libc::exp2f(x), 1.0);
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
__llvm_libc::exp2f(x), 0.5);
EXPECT_MATH_ERRNO(0);

x = float(FPBits(0xc3150000U));
EXPECT_MPFR_MATCH(mpfr::Operation::Exp2, x, __llvm_libc::exp2f(x), 1.0);
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
__llvm_libc::exp2f(x), 0.5);
EXPECT_MATH_ERRNO(0);

x = float(FPBits(0x3b42'9d37U));
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
__llvm_libc::exp2f(x), 0.5);
EXPECT_MATH_ERRNO(0);

x = float(FPBits(0xbcf3'a937U));
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
__llvm_libc::exp2f(x), 0.5);
EXPECT_MATH_ERRNO(0);
}

TEST(LlvmLibcExpfTest, Underflow) {
TEST(LlvmLibcExp2fTest, Underflow) {
errno = 0;
EXPECT_FP_EQ(0.0f, __llvm_libc::exp2f(float(FPBits(0xff7fffffU))));
EXPECT_MATH_ERRNO(ERANGE);

float x = float(FPBits(0xc3158000U));
EXPECT_MPFR_MATCH(mpfr::Operation::Exp2, x, __llvm_libc::exp2f(x), 1.0);
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
__llvm_libc::exp2f(x), 0.5);
EXPECT_MATH_ERRNO(0);

x = float(FPBits(0xc3160000U));
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
__llvm_libc::exp2f(x), 0.5);
EXPECT_MATH_ERRNO(ERANGE);

x = float(FPBits(0xc3165432U));
EXPECT_MPFR_MATCH(mpfr::Operation::Exp2, x, __llvm_libc::exp2f(x), 1.0);
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
__llvm_libc::exp2f(x), 0.5);
EXPECT_MATH_ERRNO(ERANGE);
}

TEST(LlvmLibcexp2fTest, InFloatRange) {
TEST(LlvmLibcExp2fTest, InFloatRange) {
constexpr uint32_t COUNT = 1000000;
constexpr uint32_t STEP = UINT32_MAX / COUNT;
for (uint32_t i = 0, v = 0; i <= COUNT; ++i, v += STEP) {
Expand All @@ -112,6 +135,7 @@ TEST(LlvmLibcexp2fTest, InFloatRange) {
// wider precision.
if (isnan(result) || isinf(result) || errno != 0)
continue;
ASSERT_MPFR_MATCH(mpfr::Operation::Exp2, x, __llvm_libc::exp2f(x), 1.0);
ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
__llvm_libc::exp2f(x), 0.5);
}
}