[libc][math][c23] Add nanf16 C23 math function (llvm#94767)

Part of llvm#93566.
MaxEW707 · Jun 10, 2024 · cb1a727 · cb1a727
1 parent bf0d76d
commit cb1a727
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Showing 11 changed files with 129 additions and 2 deletions.
diff --git a/libc/config/linux/aarch64/entrypoints.txt b/libc/config/linux/aarch64/entrypoints.txt
@@ -522,6 +522,7 @@ if(LIBC_TYPES_HAS_FLOAT16)
  libc.src.math.llroundf16
  libc.src.math.lrintf16
  libc.src.math.lroundf16
+ libc.src.math.nanf16
  libc.src.math.nearbyintf16
  libc.src.math.nextafterf16
  libc.src.math.nextdownf16

diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
@@ -555,6 +555,7 @@ if(LIBC_TYPES_HAS_FLOAT16)
  libc.src.math.llroundf16
  libc.src.math.lrintf16
  libc.src.math.lroundf16
+ libc.src.math.nanf16
  libc.src.math.nearbyintf16
  libc.src.math.nextafterf16
  libc.src.math.nextdownf16

diff --git a/libc/docs/math/index.rst b/libc/docs/math/index.rst
@@ -186,7 +186,7 @@ Basic Operations
 +------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
 | modf | |check| | |check| | |check| | | |check| | 7.12.6.18 | F.10.3.18 |
 +------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
-| nan | |check| | |check| | |check| |   | |check| | 7.12.11.2 | F.10.8.2 |
+| nan | |check| | |check| | |check| | |check| | |check| | 7.12.11.2 | F.10.8.2 |
 +------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
 | nearbyint | |check| | |check| | |check| | |check| | |check| | 7.12.9.3 | F.10.6.3 |
 +------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+

diff --git a/libc/include/llvm-libc-types/CMakeLists.txt b/libc/include/llvm-libc-types/CMakeLists.txt
@@ -58,7 +58,7 @@ add_header(pthread_rwlockattr_t HDR pthread_rwlockattr_t.h)
 add_header(pthread_t HDR pthread_t.h DEPENDS .__thread_type)
 add_header(rlim_t HDR rlim_t.h)
 add_header(time_t HDR time_t.h)
-add_header(stack_t HDR stack_t.h)
+add_header(stack_t HDR stack_t.h DEPENDS .size_t)
 add_header(suseconds_t HDR suseconds_t.h)
 add_header(struct_flock HDR struct_flock.h DEPENDS .off_t .pid_t)
 add_header(struct_flock64 HDR struct_flock64.h DEPENDS .off64_t .pid_t)

diff --git a/libc/spec/stdc.td b/libc/spec/stdc.td
@@ -695,6 +695,7 @@ def StdC : StandardSpec<"stdc"> {
  FunctionSpec<"nanf", RetValSpec<FloatType>, [ArgSpec<ConstCharPtr>]>,
  FunctionSpec<"nan", RetValSpec<DoubleType>, [ArgSpec<ConstCharPtr>]>,
  FunctionSpec<"nanl", RetValSpec<LongDoubleType>, [ArgSpec<ConstCharPtr>]>,
+ GuardedFunctionSpec<"nanf16", RetValSpec<Float16Type>, [ArgSpec<ConstCharPtr>], "LIBC_TYPES_HAS_FLOAT16">,
  GuardedFunctionSpec<"nanf128", RetValSpec<Float128Type>, [ArgSpec<ConstCharPtr>], "LIBC_TYPES_HAS_FLOAT128">,
 
  FunctionSpec<"canonicalize", RetValSpec<IntType>, [ArgSpec<DoubleType>, ArgSpec<DoubleType>]>,

diff --git a/libc/src/math/CMakeLists.txt b/libc/src/math/CMakeLists.txt
@@ -272,6 +272,7 @@ add_math_entrypoint_object(modff128)
 add_math_entrypoint_object(nan)
 add_math_entrypoint_object(nanf)
 add_math_entrypoint_object(nanl)
+add_math_entrypoint_object(nanf16)
 add_math_entrypoint_object(nanf128)
 
 add_math_entrypoint_object(nearbyint)

diff --git a/libc/src/math/generic/CMakeLists.txt b/libc/src/math/generic/CMakeLists.txt
@@ -2631,6 +2631,19 @@ add_entrypoint_object(
  -O3
 )
 
+add_entrypoint_object(
+ nanf16
+ SRCS
+ nanf16.cpp
+ HDRS
+ ../nanf16.h
+ DEPENDS
+ libc.src.__support.str_to_float
+ libc.src.errno.errno
+ COMPILE_OPTIONS
+ -O3
+)
+
 add_entrypoint_object(
  nanf128
  SRCS

diff --git a/libc/src/math/generic/nanf16.cpp b/libc/src/math/generic/nanf16.cpp
@@ -0,0 +1,23 @@
+//===-- Implementation of nanf16 function ---------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/math/nanf16.h"
+#include "src/__support/common.h"
+#include "src/__support/str_to_float.h"
+#include "src/errno/libc_errno.h"
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(float16, nanf16, (const char *arg)) {
+ auto result = internal::strtonan<float16>(arg);
+ if (result.has_error())
+ libc_errno = result.error;
+ return result.value;
+}
+
+} // namespace LIBC_NAMESPACE
diff --git a/libc/src/math/nanf16.h b/libc/src/math/nanf16.h
@@ -0,0 +1,20 @@
+//===-- Implementation header for nanf16 ------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_MATH_NANF16_H
+#define LLVM_LIBC_SRC_MATH_NANF16_H
+
+#include "src/__support/macros/properties/types.h"
+
+namespace LIBC_NAMESPACE {
+
+float16 nanf16(const char *arg);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_MATH_NANF16_H
diff --git a/libc/test/src/math/smoke/CMakeLists.txt b/libc/test/src/math/smoke/CMakeLists.txt
@@ -2636,6 +2636,22 @@ add_fp_unittest(
  UNIT_TEST_ONLY
 )
 
+add_fp_unittest(
+ nanf16_test
+ SUITE
+ libc-math-smoke-tests
+ SRCS
+ nanf16_test.cpp
+ DEPENDS
+ libc.include.signal
+ libc.src.math.nanf16
+ libc.src.__support.FPUtil.fp_bits
+ libc.src.__support.macros.sanitizer
+ # FIXME: The nan tests currently have death tests, which aren't supported for
+ # hermetic tests.
+ UNIT_TEST_ONLY
+)
+
 add_fp_unittest(
  nanf128_test
  SUITE

diff --git a/libc/test/src/math/smoke/nanf16_test.cpp b/libc/test/src/math/smoke/nanf16_test.cpp
@@ -0,0 +1,51 @@
+//===-- Unittests for nanf16 ----------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/__support/FPUtil/FPBits.h"
+#include "src/__support/macros/sanitizer.h"
+#include "src/math/nanf16.h"
+#include "test/UnitTest/FEnvSafeTest.h"
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+
+#include <signal.h>
+
+class LlvmLibcNanf16Test : public LIBC_NAMESPACE::testing::FEnvSafeTest {
+public:
+ using StorageType = LIBC_NAMESPACE::fputil::FPBits<float16>::StorageType;
+
+ void run_test(const char *input_str, StorageType bits) {
+ float16 result = LIBC_NAMESPACE::nanf16(input_str);
+ auto actual_fp = LIBC_NAMESPACE::fputil::FPBits<float16>(result);
+ auto expected_fp = LIBC_NAMESPACE::fputil::FPBits<float16>(bits);
+ EXPECT_EQ(actual_fp.uintval(), expected_fp.uintval());
+ };
+};
+
+TEST_F(LlvmLibcNanf16Test, NCharSeq) {
+ run_test("", 0x7e00);
+ run_test("123", 0x7e7b);
+ run_test("0x123", 0x7f23);
+ run_test("1a", 0x7e00);
+ run_test("1234567890qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM_",
+ 0x7e00);
+ run_test("10000000000000000000000000000000000000000000000000", 0x7e00);
+}
+
+TEST_F(LlvmLibcNanf16Test, RandomString) {
+ run_test(" 1234", 0x7e00);
+ run_test("-1234", 0x7e00);
+ run_test("asd&f", 0x7e00);
+ run_test("123 ", 0x7e00);
+}
+
+#ifndef LIBC_HAVE_ADDRESS_SANITIZER
+TEST_F(LlvmLibcNanf16Test, InvalidInput) {
+ EXPECT_DEATH([] { LIBC_NAMESPACE::nanf16(nullptr); }, WITH_SIGNAL(SIGSEGV));
+}
+#endif // LIBC_HAVE_ADDRESS_SANITIZER