[libc][stdbit] implement stdc_trailing_zeros (C23) #80344

nickdesaulniers · 2024-02-01T21:38:49Z

No description provided.

llvmbot · 2024-02-01T21:39:22Z

@llvm/pr-subscribers-libc

Author: Nick Desaulniers (nickdesaulniers)

Changes

Patch is 20.91 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/80344.diff

20 Files Affected:

(modified) libc/config/linux/x86_64/entrypoints.txt (+5)
(modified) libc/include/llvm-libc-macros/stdbit-macros.h (+22)
(modified) libc/src/stdbit/CMakeLists.txt (+50)
(added) libc/src/stdbit/stdc_trailing_zeros_uc.cpp (+20)
(added) libc/src/stdbit/stdc_trailing_zeros_uc.h (+18)
(added) libc/src/stdbit/stdc_trailing_zeros_ui.cpp (+20)
(added) libc/src/stdbit/stdc_trailing_zeros_ui.h (+18)
(added) libc/src/stdbit/stdc_trailing_zeros_ul.cpp (+20)
(added) libc/src/stdbit/stdc_trailing_zeros_ul.h (+18)
(added) libc/src/stdbit/stdc_trailing_zeros_ull.cpp (+20)
(added) libc/src/stdbit/stdc_trailing_zeros_ull.h (+18)
(added) libc/src/stdbit/stdc_trailing_zeros_us.cpp (+20)
(added) libc/src/stdbit/stdc_trailing_zeros_us.h (+18)
(modified) libc/test/include/stdbit_test.cpp (+13)
(modified) libc/test/src/stdbit/CMakeLists.txt (+55)
(added) libc/test/src/stdbit/stdc_trailing_zeros_uc_test.cpp (+21)
(added) libc/test/src/stdbit/stdc_trailing_zeros_ui_test.cpp (+21)
(added) libc/test/src/stdbit/stdc_trailing_zeros_ul_test.cpp (+21)
(added) libc/test/src/stdbit/stdc_trailing_zeros_ull_test.cpp (+21)
(added) libc/test/src/stdbit/stdc_trailing_zeros_us_test.cpp (+21)

diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
index 9946b93c346ce..3ba676fc496ec 100644
--- a/libc/config/linux/x86_64/entrypoints.txt
+++ b/libc/config/linux/x86_64/entrypoints.txt
@@ -102,6 +102,11 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.stdbit.stdc_leading_ones_ui
     libc.src.stdbit.stdc_leading_ones_ul
     libc.src.stdbit.stdc_leading_ones_ull
+    libc.src.stdbit.stdc_trailing_zeros_uc
+    libc.src.stdbit.stdc_trailing_zeros_us
+    libc.src.stdbit.stdc_trailing_zeros_ui
+    libc.src.stdbit.stdc_trailing_zeros_ul
+    libc.src.stdbit.stdc_trailing_zeros_ull
 
     # stdlib.h entrypoints
     libc.src.stdlib.abs
diff --git a/libc/include/llvm-libc-macros/stdbit-macros.h b/libc/include/llvm-libc-macros/stdbit-macros.h
index cc964a5268b0d..a36d221b3c835 100644
--- a/libc/include/llvm-libc-macros/stdbit-macros.h
+++ b/libc/include/llvm-libc-macros/stdbit-macros.h
@@ -40,6 +40,21 @@ inline unsigned stdc_leading_ones(unsigned long x) {
 inline unsigned stdc_leading_ones(unsigned long long x) {
   return stdc_leading_ones_ull(x);
 }
+inline unsigned stdc_trailing_zeros(unsigned char x) {
+  return stdc_trailing_zeros_uc(x);
+}
+inline unsigned stdc_trailing_zeros(unsigned short x) {
+  return stdc_trailing_zeros_us(x);
+}
+inline unsigned stdc_trailing_zeros(unsigned x) {
+  return stdc_trailing_zeros_ui(x);
+}
+inline unsigned stdc_trailing_zeros(unsigned long x) {
+  return stdc_trailing_zeros_ul(x);
+}
+inline unsigned stdc_trailing_zeros(unsigned long long x) {
+  return stdc_trailing_zeros_ull(x);
+}
 #else
 #define stdc_leading_zeros(x)                                                  \
   _Generic((x),                                                                \
@@ -55,6 +70,13 @@ inline unsigned stdc_leading_ones(unsigned long long x) {
       unsigned: stdc_leading_ones_ui,                                          \
       unsigned long: stdc_leading_ones_ul,                                     \
       unsigned long long: stdc_leading_ones_ull)(x)
+#define stdc_trailing_zeros(x)                                                  \
+  _Generic((x),                                                                \
+      unsigned char: stdc_trailing_zeros_uc,                                    \
+      unsigned short: stdc_trailing_zeros_us,                                   \
+      unsigned: stdc_trailing_zeros_ui,                                         \
+      unsigned long: stdc_trailing_zeros_ul,                                    \
+      unsigned long long: stdc_trailing_zeros_ull)(x)
 #endif // __cplusplus
 
 #endif // __LLVM_LIBC_MACROS_STDBIT_MACROS_H
diff --git a/libc/src/stdbit/CMakeLists.txt b/libc/src/stdbit/CMakeLists.txt
index d7daff44dfda6..1c9f1b90281cd 100644
--- a/libc/src/stdbit/CMakeLists.txt
+++ b/libc/src/stdbit/CMakeLists.txt
@@ -97,3 +97,53 @@ add_entrypoint_object(
   DEPENDS
     libc.src.__support.CPP.bit
 )
+
+add_entrypoint_object(
+  stdc_trailing_zeros_uc
+  SRCS
+    stdc_trailing_zeros_uc.cpp
+  HDRS
+    stdc_trailing_zeros_uc.h
+  DEPENDS
+    libc.src.__support.CPP.bit
+)
+
+add_entrypoint_object(
+  stdc_trailing_zeros_us
+  SRCS
+    stdc_trailing_zeros_us.cpp
+  HDRS
+    stdc_trailing_zeros_us.h
+  DEPENDS
+    libc.src.__support.CPP.bit
+)
+
+add_entrypoint_object(
+  stdc_trailing_zeros_ui
+  SRCS
+    stdc_trailing_zeros_ui.cpp
+  HDRS
+    stdc_trailing_zeros_ui.h
+  DEPENDS
+    libc.src.__support.CPP.bit
+)
+
+add_entrypoint_object(
+  stdc_trailing_zeros_ul
+  SRCS
+    stdc_trailing_zeros_ul.cpp
+  HDRS
+    stdc_trailing_zeros_ul.h
+  DEPENDS
+    libc.src.__support.CPP.bit
+)
+
+add_entrypoint_object(
+  stdc_trailing_zeros_ull
+  SRCS
+    stdc_trailing_zeros_ull.cpp
+  HDRS
+    stdc_trailing_zeros_ull.h
+  DEPENDS
+    libc.src.__support.CPP.bit
+)
diff --git a/libc/src/stdbit/stdc_trailing_zeros_uc.cpp b/libc/src/stdbit/stdc_trailing_zeros_uc.cpp
new file mode 100644
index 0000000000000..36924c5a053ad
--- /dev/null
+++ b/libc/src/stdbit/stdc_trailing_zeros_uc.cpp
@@ -0,0 +1,20 @@
+//===-- Implementation of stdc_trailing_zeros_uc --------------------------===//
+//
+// 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/stdbit/stdc_trailing_zeros_uc.h"
+
+#include "src/__support/CPP/bit.h"
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(unsigned, stdc_trailing_zeros_uc, (unsigned char value)) {
+  return static_cast<unsigned>(cpp::countr_zero(value));
+}
+
+} // namespace LIBC_NAMESPACE
diff --git a/libc/src/stdbit/stdc_trailing_zeros_uc.h b/libc/src/stdbit/stdc_trailing_zeros_uc.h
new file mode 100644
index 0000000000000..866201e5acea8
--- /dev/null
+++ b/libc/src/stdbit/stdc_trailing_zeros_uc.h
@@ -0,0 +1,18 @@
+//===-- Implementation header for stdc_trailing_zeros_uc --------*- 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_STDBIT_STDC_TRAILING_ZEROS_UC_H
+#define LLVM_LIBC_SRC_STDBIT_STDC_TRAILING_ZEROS_UC_H
+
+namespace LIBC_NAMESPACE {
+
+unsigned stdc_trailing_zeros_uc(unsigned char value);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_STDBIT_STDC_TRAILING_ZEROS_UC_H
diff --git a/libc/src/stdbit/stdc_trailing_zeros_ui.cpp b/libc/src/stdbit/stdc_trailing_zeros_ui.cpp
new file mode 100644
index 0000000000000..a264fd97f251f
--- /dev/null
+++ b/libc/src/stdbit/stdc_trailing_zeros_ui.cpp
@@ -0,0 +1,20 @@
+//===-- Implementation of stdc_trailing_zeros_ui --------------------------===//
+//
+// 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/stdbit/stdc_trailing_zeros_ui.h"
+
+#include "src/__support/CPP/bit.h"
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(unsigned, stdc_trailing_zeros_ui, (unsigned value)) {
+  return static_cast<unsigned>(cpp::countr_zero(value));
+}
+
+} // namespace LIBC_NAMESPACE
diff --git a/libc/src/stdbit/stdc_trailing_zeros_ui.h b/libc/src/stdbit/stdc_trailing_zeros_ui.h
new file mode 100644
index 0000000000000..0642e312f4fe7
--- /dev/null
+++ b/libc/src/stdbit/stdc_trailing_zeros_ui.h
@@ -0,0 +1,18 @@
+//===-- Implementation header for stdc_trailing_zeros_ui --------*- 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_STDBIT_STDC_TRAILING_ZEROS_UI_H
+#define LLVM_LIBC_SRC_STDBIT_STDC_TRAILING_ZEROS_UI_H
+
+namespace LIBC_NAMESPACE {
+
+unsigned stdc_trailing_zeros_ui(unsigned value);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_STDBIT_STDC_TRAILING_ZEROS_UI_H
diff --git a/libc/src/stdbit/stdc_trailing_zeros_ul.cpp b/libc/src/stdbit/stdc_trailing_zeros_ul.cpp
new file mode 100644
index 0000000000000..8e0c36cb09965
--- /dev/null
+++ b/libc/src/stdbit/stdc_trailing_zeros_ul.cpp
@@ -0,0 +1,20 @@
+//===-- Implementation of stdc_trailing_zeros_ul --------------------------===//
+//
+// 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/stdbit/stdc_trailing_zeros_ul.h"
+
+#include "src/__support/CPP/bit.h"
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(unsigned, stdc_trailing_zeros_ul, (unsigned long value)) {
+  return static_cast<unsigned>(cpp::countr_zero(value));
+}
+
+} // namespace LIBC_NAMESPACE
diff --git a/libc/src/stdbit/stdc_trailing_zeros_ul.h b/libc/src/stdbit/stdc_trailing_zeros_ul.h
new file mode 100644
index 0000000000000..e10b4474753a0
--- /dev/null
+++ b/libc/src/stdbit/stdc_trailing_zeros_ul.h
@@ -0,0 +1,18 @@
+//===-- Implementation header for stdc_trailing_zeros_ul --------*- 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_STDBIT_STDC_TRAILING_ZEROS_UL_H
+#define LLVM_LIBC_SRC_STDBIT_STDC_TRAILING_ZEROS_UL_H
+
+namespace LIBC_NAMESPACE {
+
+unsigned stdc_trailing_zeros_ul(unsigned long value);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_STDBIT_STDC_TRAILING_ZEROS_UL_H
diff --git a/libc/src/stdbit/stdc_trailing_zeros_ull.cpp b/libc/src/stdbit/stdc_trailing_zeros_ull.cpp
new file mode 100644
index 0000000000000..9e61eccf2e4ef
--- /dev/null
+++ b/libc/src/stdbit/stdc_trailing_zeros_ull.cpp
@@ -0,0 +1,20 @@
+//===-- Implementation of stdc_trailing_zeros_ull -------------------------===//
+//
+// 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/stdbit/stdc_trailing_zeros_ull.h"
+
+#include "src/__support/CPP/bit.h"
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(unsigned, stdc_trailing_zeros_ull, (unsigned long long value)) {
+  return static_cast<unsigned>(cpp::countr_zero(value));
+}
+
+} // namespace LIBC_NAMESPACE
diff --git a/libc/src/stdbit/stdc_trailing_zeros_ull.h b/libc/src/stdbit/stdc_trailing_zeros_ull.h
new file mode 100644
index 0000000000000..f95169d29f45e
--- /dev/null
+++ b/libc/src/stdbit/stdc_trailing_zeros_ull.h
@@ -0,0 +1,18 @@
+//===-- Implementation header for stdc_trailing_zeros_ull -------*- 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_STDBIT_STDC_TRAILING_ZEROS_ULL_H
+#define LLVM_LIBC_SRC_STDBIT_STDC_TRAILING_ZEROS_ULL_H
+
+namespace LIBC_NAMESPACE {
+
+unsigned stdc_trailing_zeros_ull(unsigned long long value);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_STDBIT_STDC_TRAILING_ZEROS_ULL_H
diff --git a/libc/src/stdbit/stdc_trailing_zeros_us.cpp b/libc/src/stdbit/stdc_trailing_zeros_us.cpp
new file mode 100644
index 0000000000000..a5b9f4a7d8498
--- /dev/null
+++ b/libc/src/stdbit/stdc_trailing_zeros_us.cpp
@@ -0,0 +1,20 @@
+//===-- Implementation of stdc_trailing_zeros_us --------------------------===//
+//
+// 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/stdbit/stdc_trailing_zeros_us.h"
+
+#include "src/__support/CPP/bit.h"
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(unsigned, stdc_trailing_zeros_us, (unsigned short value)) {
+  return static_cast<unsigned>(cpp::countr_zero(value));
+}
+
+} // namespace LIBC_NAMESPACE
diff --git a/libc/src/stdbit/stdc_trailing_zeros_us.h b/libc/src/stdbit/stdc_trailing_zeros_us.h
new file mode 100644
index 0000000000000..ddbdf0d647abd
--- /dev/null
+++ b/libc/src/stdbit/stdc_trailing_zeros_us.h
@@ -0,0 +1,18 @@
+//===-- Implementation header for stdc_trailing_zeros_us --------*- 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_STDBIT_STDC_TRAILING_ZEROS_US_H
+#define LLVM_LIBC_SRC_STDBIT_STDC_TRAILING_ZEROS_US_H
+
+namespace LIBC_NAMESPACE {
+
+unsigned stdc_trailing_zeros_us(unsigned short value);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_STDBIT_STDC_TRAILING_ZEROS_US_H
diff --git a/libc/test/include/stdbit_test.cpp b/libc/test/include/stdbit_test.cpp
index 6e48b0f2f7594..858dc08bfd70c 100644
--- a/libc/test/include/stdbit_test.cpp
+++ b/libc/test/include/stdbit_test.cpp
@@ -33,6 +33,11 @@ unsigned stdc_leading_ones_us(unsigned short) noexcept { return 0xBBU; }
 unsigned stdc_leading_ones_ui(unsigned) noexcept { return 0xBCU; }
 unsigned stdc_leading_ones_ul(unsigned long) noexcept { return 0xBDU; }
 unsigned stdc_leading_ones_ull(unsigned long long) noexcept { return 0xBFU; }
+unsigned stdc_trailing_zeros_uc(unsigned char) noexcept { return 0xCAU; }
+unsigned stdc_trailing_zeros_us(unsigned short) noexcept { return 0xCBU; }
+unsigned stdc_trailing_zeros_ui(unsigned) noexcept { return 0xCCU; }
+unsigned stdc_trailing_zeros_ul(unsigned long) noexcept { return 0xCDU; }
+unsigned stdc_trailing_zeros_ull(unsigned long long) noexcept { return 0xCFU; }
 }
 
 #include "include/llvm-libc-macros/stdbit-macros.h"
@@ -52,3 +57,11 @@ TEST(LlvmLibcStdbitTest, TypeGenericMacroLeadingOnes) {
   EXPECT_EQ(stdc_leading_ones(0UL), 0xBDU);
   EXPECT_EQ(stdc_leading_ones(0ULL), 0xBFU);
 }
+
+TEST(LlvmLibcStdbitTest, TypeGenericMacroTrailingZeros) {
+  EXPECT_EQ(stdc_trailing_zeros(static_cast<unsigned char>(0U)), 0xCAU);
+  EXPECT_EQ(stdc_trailing_zeros(static_cast<unsigned short>(0U)), 0xCBU);
+  EXPECT_EQ(stdc_trailing_zeros(0U), 0xCCU);
+  EXPECT_EQ(stdc_trailing_zeros(0UL), 0xCDU);
+  EXPECT_EQ(stdc_trailing_zeros(0ULL), 0xCFU);
+}
diff --git a/libc/test/src/stdbit/CMakeLists.txt b/libc/test/src/stdbit/CMakeLists.txt
index a8c3c9f883532..8a7a227eea47f 100644
--- a/libc/test/src/stdbit/CMakeLists.txt
+++ b/libc/test/src/stdbit/CMakeLists.txt
@@ -110,3 +110,58 @@ add_libc_test(
     libc.src.stdbit.stdc_leading_ones_ull
 )
 
+add_libc_test(
+  stdc_trailing_zeros_uc_test
+  SUITE
+    libc-stdbit-tests
+  SRCS
+    stdc_trailing_zeros_uc_test.cpp
+  DEPENDS
+    libc.src.__support.CPP.limits
+    libc.src.stdbit.stdc_trailing_zeros_uc
+)
+
+add_libc_test(
+  stdc_trailing_zeros_us_test
+  SUITE
+    libc-stdbit-tests
+  SRCS
+    stdc_trailing_zeros_us_test.cpp
+  DEPENDS
+    libc.src.__support.CPP.limits
+    libc.src.stdbit.stdc_trailing_zeros_us
+)
+
+add_libc_test(
+  stdc_trailing_zeros_ui_test
+  SUITE
+    libc-stdbit-tests
+  SRCS
+    stdc_trailing_zeros_ui_test.cpp
+  DEPENDS
+    libc.src.__support.CPP.limits
+    libc.src.stdbit.stdc_trailing_zeros_ui
+)
+
+add_libc_test(
+  stdc_trailing_zeros_ul_test
+  SUITE
+    libc-stdbit-tests
+  SRCS
+    stdc_trailing_zeros_ul_test.cpp
+  DEPENDS
+    libc.src.__support.CPP.limits
+    libc.src.stdbit.stdc_trailing_zeros_ul
+)
+
+add_libc_test(
+  stdc_trailing_zeros_ull_test
+  SUITE
+    libc-stdbit-tests
+  SRCS
+    stdc_trailing_zeros_ull_test.cpp
+  DEPENDS
+    libc.src.__support.CPP.limits
+    libc.src.stdbit.stdc_trailing_zeros_ull
+)
+
diff --git a/libc/test/src/stdbit/stdc_trailing_zeros_uc_test.cpp b/libc/test/src/stdbit/stdc_trailing_zeros_uc_test.cpp
new file mode 100644
index 0000000000000..725b276d9de4c
--- /dev/null
+++ b/libc/test/src/stdbit/stdc_trailing_zeros_uc_test.cpp
@@ -0,0 +1,21 @@
+//===-- Unittests for stdc_trailing_zeros_uc --------------------------------===//
+//
+// 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/CPP/limits.h"
+#include "src/stdbit/stdc_trailing_zeros_uc.h"
+#include "test/UnitTest/Test.h"
+
+TEST(LlvmLibcStdcTrailingZerosUcTest, Zero) {
+  EXPECT_EQ(LIBC_NAMESPACE::stdc_trailing_zeros_uc(0U),
+            static_cast<unsigned>(UCHAR_WIDTH));
+}
+
+TEST(LlvmLibcStdcTrailingZerosUcTest, OneHot) {
+  for (unsigned i = 0U; i != UCHAR_WIDTH; ++i)
+    EXPECT_EQ(LIBC_NAMESPACE::stdc_trailing_zeros_uc(1U << i), i);
+}
diff --git a/libc/test/src/stdbit/stdc_trailing_zeros_ui_test.cpp b/libc/test/src/stdbit/stdc_trailing_zeros_ui_test.cpp
new file mode 100644
index 0000000000000..1ed7e66bf9097
--- /dev/null
+++ b/libc/test/src/stdbit/stdc_trailing_zeros_ui_test.cpp
@@ -0,0 +1,21 @@
+//===-- Unittests for stdc_trailing_zeros_ui --------------------------------===//
+//
+// 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/CPP/limits.h"
+#include "src/stdbit/stdc_trailing_zeros_ui.h"
+#include "test/UnitTest/Test.h"
+
+TEST(LlvmLibcStdcTrailingZerosUiTest, Zero) {
+  EXPECT_EQ(LIBC_NAMESPACE::stdc_trailing_zeros_ui(0U),
+            static_cast<unsigned>(UINT_WIDTH));
+}
+
+TEST(LlvmLibcStdcTrailingZerosUiTest, OneHot) {
+  for (unsigned i = 0U; i != UINT_WIDTH; ++i)
+    EXPECT_EQ(LIBC_NAMESPACE::stdc_trailing_zeros_ui(1U << i), i);
+}
diff --git a/libc/test/src/stdbit/stdc_trailing_zeros_ul_test.cpp b/libc/test/src/stdbit/stdc_trailing_zeros_ul_test.cpp
new file mode 100644
index 0000000000000..c46d48b49ec43
--- /dev/null
+++ b/libc/test/src/stdbit/stdc_trailing_zeros_ul_test.cpp
@@ -0,0 +1,21 @@
+//===-- Unittests for stdc_trailing_zeros_ul --------------------------------===//
+//
+// 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/CPP/limits.h"
+#include "src/stdbit/stdc_trailing_zeros_ul.h"
+#include "test/UnitTest/Test.h"
+
+TEST(LlvmLibcStdcTrailingZerosUlTest, Zero) {
+  EXPECT_EQ(LIBC_NAMESPACE::stdc_trailing_zeros_ul(0U),
+            static_cast<unsigned>(ULONG_WIDTH));
+}
+
+TEST(LlvmLibcStdcTrailingZerosUlTest, OneHot) {
+  for (unsigned i = 0U; i != ULONG_WIDTH; ++i)
+    EXPECT_EQ(LIBC_NAMESPACE::stdc_trailing_zeros_ul(1UL << i), i);
+}
diff --git a/libc/test/src/stdbit/stdc_trailing_zeros_ull_test.cpp b/libc/test/src/stdbit/stdc_trailing_zeros_ull_test.cpp
new file mode 100644
index 0000000000000..e925b785dc57a
--- /dev/null
+++ b/libc/test/src/stdbit/stdc_trailing_zeros_ull_test.cpp
@@ -0,0 +1,21 @@
+//===-- Unittests for stdc_trailing_zeros_ull -----------------------------===//
+//
+// 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/CPP/limits.h"
+#include "src/stdbit/stdc_trailing_zeros_ull.h"
+#include "test/UnitTest/Test.h"
+
+TEST(LlvmLibcStdcTrailingZerosUllTest, Zero) {
+  EXPECT_EQ(LIBC_NAMESPACE::stdc_trailing_zeros_ull(0U),
+            static_cast<unsigned>(LLONG_WIDTH));
+}
+
+TEST(LlvmLibcStdcTrailingZerosUllTest, OneHot) {
+  for (unsigned i = 0U; i != ULLONG_WIDTH; ++i)
+    EXPECT_EQ(LIBC_NAMESPACE::stdc_trailing_zeros_ull(1ULL << i), i);
+}
diff --git a/libc/test/src/stdbit/stdc_trailing_zeros_us_test.cpp b/libc/test/src/stdbit/stdc_trailing_zeros_us_test.cpp
new file mode 100644
index 0000000000000..6e56...
[truncated]

github-actions · 2024-02-01T21:41:18Z

✅ With the latest revision this PR passed the C/C++ code formatter.

nickdesaulniers · 2024-02-01T23:52:33Z

update docs!

libc/test/src/stdbit/stdc_trailing_zeros_ull_test.cpp

nickdesaulniers · 2024-02-02T00:00:13Z

needs to update libc/spec/stdc.td, too.

libc/spec/stdc.td

lntue · 2024-02-02T22:02:11Z

libc/test/src/stdbit/CMakeLists.txt

-    libc.src.stdbit.stdc_leading_ones_ull
-)
-
+list(APPEND prefixes


I think you should set(prefixes ...) and set(suffixes ...) instead of appending, just in case they were set somewhere before.

done in 5d94dd3 PTAL

lntue · 2024-02-02T22:02:49Z

libc/src/stdbit/CMakeLists.txt

-  DEPENDS
-    libc.src.__support.CPP.bit
-)
+list(APPEND prefixes


I think you should set(prefixes ...) and set(suffixes ...) instead of appending, just in case they were set somewhere before.

done in 5d94dd3 PTAL

[libc][stdbit] implement stdc_trailing_zeros (C23)

995f36d

llvmbot added the libc label Feb 1, 2024

nickdesaulniers added 2 commits February 1, 2024 13:53

format

984693d

refactor cmake; getting tired of writing these already

68d1f7f

nickdesaulniers marked this pull request as draft February 1, 2024 23:52

nickdesaulniers commented Feb 1, 2024

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libc/test/src/stdbit/stdc_trailing_zeros_ull_test.cpp Outdated Show resolved Hide resolved

nickdesaulniers added 2 commits February 2, 2024 08:19

s/LLONG_WIDTH/ULLONG_WIDTH/

ccc4daa

update stdc.td

4cdccb5

nickdesaulniers marked this pull request as ready for review February 2, 2024 16:21

nickdesaulniers mentioned this pull request Feb 2, 2024

[libc][stdbit] implement stdc_trailing_ones (C23) #80459

Merged

nickdesaulniers commented Feb 2, 2024

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libc/spec/stdc.td Show resolved Hide resolved

nickdesaulniers marked this pull request as draft February 2, 2024 17:32

update macros in spect.td

282a079

nickdesaulniers marked this pull request as ready for review February 2, 2024 19:31

lntue reviewed Feb 2, 2024

View reviewed changes

prefer set to list APPEND

5d94dd3

lntue approved these changes Feb 5, 2024

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nickdesaulniers merged commit d5a3de4 into llvm:main Feb 6, 2024

nickdesaulniers deleted the trailing_zeros branch February 6, 2024 14:27

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