[libc] Implement wcstod and wcstold. (#168020)

These are simply implemented as specializations of strtofloatingpoint
for double / long double and for wchar_t. The unit tests are copied from
the strtod / strtold ones.

Author: vonosmas

libc/config/linux/x86_64/entrypoints.txt

@@ -398,9 +398,11 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.wchar.wmemchr
     libc.src.wchar.wcpcpy
     libc.src.wchar.wcpncpy
+    libc.src.wchar.wcstod
     libc.src.wchar.wcstof
     libc.src.wchar.wcstok
     libc.src.wchar.wcstol
+    libc.src.wchar.wcstold
     libc.src.wchar.wcstoll
     libc.src.wchar.wcstoul
     libc.src.wchar.wcstoull

libc/include/wchar.yaml

@@ -367,3 +367,17 @@ functions:
     arguments:
       - type: const wchar_t *__restrict
       - type: wchar_t **__restrict
+  - name: wcstod
+    standards:
+      - stdc
+    return_type: double
+    arguments:
+      - type: const wchar_t *__restrict
+      - type: wchar_t **__restrict
+  - name: wcstold
+    standards:
+      - stdc
+    return_type: long double
+    arguments:
+      - type: const wchar_t *__restrict
+      - type: wchar_t **__restrict

libc/src/wchar/CMakeLists.txt

@@ -110,6 +110,28 @@ add_entrypoint_object(
     libc.src.errno.errno
 )
 
+add_entrypoint_object(
+  wcstod
+  SRCS
+    wcstod.cpp
+  HDRS
+    wcstod.h
+  DEPENDS
+    libc.src.__support.str_to_float
+    libc.src.errno.errno
+)
+
+add_entrypoint_object(
+  wcstold
+  SRCS
+    wcstold.cpp
+  HDRS
+    wcstold.h
+  DEPENDS
+    libc.src.__support.str_to_float
+    libc.src.errno.errno
+)
+
 add_entrypoint_object(
   wcstok
   SRCS

libc/src/wchar/wcstod.cpp

@@ -0,0 +1,30 @@
+//===-- Implementation of wcstod ------------------------------------------===//
+//
+// 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/wchar/wcstod.h"
+#include "src/__support/common.h"
+#include "src/__support/libc_errno.h"
+#include "src/__support/macros/config.h"
+#include "src/__support/str_to_float.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(double, wcstod,
+                   (const wchar_t *__restrict str,
+                    wchar_t **__restrict str_end)) {
+  auto result = internal::strtofloatingpoint<double>(str);
+  if (result.has_error())
+    libc_errno = result.error;
+
+  if (str_end != nullptr)
+    *str_end = const_cast<wchar_t *>(str + result.parsed_len);
+
+  return result.value;
+}
+
+} // namespace LIBC_NAMESPACE_DECL

libc/src/wchar/wcstod.h

@@ -0,0 +1,20 @@
+//===-- Implementation header for wcstod ------------------------*- 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_WCHAR_WCSTOD_H
+#define LLVM_LIBC_SRC_WCHAR_WCSTOD_H
+
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+double wcstod(const wchar_t *__restrict str, wchar_t **__restrict str_end);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_WCHAR_WCSTOD_H

libc/src/wchar/wcstold.cpp

@@ -0,0 +1,30 @@
+//===-- Implementation of wcstold -----------------------------------------===//
+//
+// 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/wchar/wcstold.h"
+#include "src/__support/common.h"
+#include "src/__support/libc_errno.h"
+#include "src/__support/macros/config.h"
+#include "src/__support/str_to_float.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(long double, wcstold,
+                   (const wchar_t *__restrict str,
+                    wchar_t **__restrict str_end)) {
+  auto result = internal::strtofloatingpoint<long double>(str);
+  if (result.has_error())
+    libc_errno = result.error;
+
+  if (str_end != nullptr)
+    *str_end = const_cast<wchar_t *>(str + result.parsed_len);
+
+  return result.value;
+}
+
+} // namespace LIBC_NAMESPACE_DECL

libc/src/wchar/wcstold.h

@@ -0,0 +1,21 @@
+//===-- Implementation header for wcstold -----------------------*- 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_WCHAR_WCSTOLD_H
+#define LLVM_LIBC_SRC_WCHAR_WCSTOLD_H
+
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+long double wcstold(const wchar_t *__restrict str,
+                    wchar_t **__restrict str_end);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_WCHAR_WCSTOLD_H

libc/test/src/wchar/CMakeLists.txt

@@ -538,5 +538,32 @@ add_libc_test(
   DEPENDS
     libc.src.wchar.wcstof
     libc.test.UnitTest.ErrnoCheckingTest
-    libc.test.UnitTest.LibcFPTestHelpers
+  LINK_LIBRARIES
+    LibcFPTestHelpers
+)
+
+add_libc_test(
+  wcstod_test
+  SUITE
+    libc_wchar_unittests
+  SRCS
+    wcstod_test.cpp
+  DEPENDS
+    libc.src.wchar.wcstod
+    libc.test.UnitTest.ErrnoCheckingTest
+  LINK_LIBRARIES
+    LibcFPTestHelpers
+)
+
+add_libc_test(
+  wcstold_test
+  SUITE
+    libc_wchar_unittests
+  SRCS
+    wcstold_test.cpp
+  DEPENDS
+    libc.src.__support.FPUtil.fp_bits
+    libc.src.__support.uint128
+    libc.src.wchar.wcstold
+    libc.test.UnitTest.ErrnoCheckingTest
 )