[libc][stdbit][c23] adds implementation of stdc_bit_ceil functions (l…

…lvm#84657)

Closes llvm#84652.

Based on llvm#84233.

libc/config/linux/x86_64/entrypoints.txt

@@ -158,6 +158,11 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.stdbit.stdc_bit_floor_ui
     libc.src.stdbit.stdc_bit_floor_ul
     libc.src.stdbit.stdc_bit_floor_ull
+    libc.src.stdbit.stdc_bit_ceil_uc
+    libc.src.stdbit.stdc_bit_ceil_us
+    libc.src.stdbit.stdc_bit_ceil_ui
+    libc.src.stdbit.stdc_bit_ceil_ul
+    libc.src.stdbit.stdc_bit_ceil_ull
 
     # stdlib.h entrypoints
     libc.src.stdlib.abs

libc/docs/stdbit.rst

@@ -96,11 +96,11 @@ stdc_bit_floor_us            |check|
 stdc_bit_floor_ui            |check|
 stdc_bit_floor_ul            |check|
 stdc_bit_floor_ull           |check|
-stdc_bit_ceil_uc
-stdc_bit_ceil_us
-stdc_bit_ceil_ui
-stdc_bit_ceil_ul
-stdc_bit_ceil_ull
+stdc_bit_ceil_uc             |check|
+stdc_bit_ceil_us             |check|
+stdc_bit_ceil_ui             |check|
+stdc_bit_ceil_ul             |check|
+stdc_bit_ceil_ull            |check|
 ============================ =========
 
 
@@ -127,7 +127,7 @@ stdc_count_ones            |check|
 stdc_has_single_bit        |check|
 stdc_bit_width             |check|
 stdc_bit_floor             |check|
-stdc_bit_ceil
+stdc_bit_ceil              |check|
 =========================  =========
 
 Standards

libc/include/llvm-libc-macros/stdbit-macros.h

@@ -194,6 +194,19 @@ inline unsigned long stdc_bit_floor(unsigned long x) {
 inline unsigned long long stdc_bit_floor(unsigned long long x) {
   return stdc_bit_floor_ull(x);
 }
+inline unsigned char stdc_bit_ceil(unsigned char x) {
+  return stdc_bit_ceil_uc(x);
+}
+inline unsigned short stdc_bit_ceil(unsigned short x) {
+  return stdc_bit_ceil_us(x);
+}
+inline unsigned stdc_bit_ceil(unsigned x) { return stdc_bit_ceil_ui(x); }
+inline unsigned long stdc_bit_ceil(unsigned long x) {
+  return stdc_bit_ceil_ul(x);
+}
+inline unsigned long long stdc_bit_ceil(unsigned long long x) {
+  return stdc_bit_ceil_ull(x);
+}
 #else
 #define stdc_leading_zeros(x)                                                  \
   _Generic((x),                                                                \
@@ -286,6 +299,13 @@ inline unsigned long long stdc_bit_floor(unsigned long long x) {
       unsigned: stdc_bit_floor_ui,                                             \
       unsigned long: stdc_bit_floor_ul,                                        \
       unsigned long long: stdc_bit_floor_ull)(x)
+#define stdc_bit_ceil(x)                                                       \
+  _Generic((x),                                                                \
+      unsigned char: stdc_bit_ceil_uc,                                         \
+      unsigned short: stdc_bit_ceil_us,                                        \
+      unsigned: stdc_bit_ceil_ui,                                              \
+      unsigned long: stdc_bit_ceil_ul,                                         \
+      unsigned long long: stdc_bit_ceil_ull)(x)
 #endif // __cplusplus
 
 #endif // __LLVM_LIBC_MACROS_STDBIT_MACROS_H

libc/spec/stdc.td

@@ -816,7 +816,8 @@ def StdC : StandardSpec<"stdc"> {
         Macro<"stdc_count_ones">,
         Macro<"stdc_has_single_bit">,
         Macro<"std_bit_width">,
-        Macro<"std_bit_floor">
+        Macro<"std_bit_floor">,
+        Macro<"std_bit_ceil">
       ], // Macros
       [], // Types
       [], // Enumerations
@@ -880,7 +881,12 @@ def StdC : StandardSpec<"stdc"> {
           FunctionSpec<"stdc_bit_floor_us", RetValSpec<UnsignedShortType>, [ArgSpec<UnsignedShortType>]>,
           FunctionSpec<"stdc_bit_floor_ui", RetValSpec<UnsignedIntType>, [ArgSpec<UnsignedIntType>]>,
           FunctionSpec<"stdc_bit_floor_ul", RetValSpec<UnsignedLongType>, [ArgSpec<UnsignedLongType>]>,
-          FunctionSpec<"stdc_bit_floor_ull", RetValSpec<UnsignedLongLongType>, [ArgSpec<UnsignedLongLongType>]>
+          FunctionSpec<"stdc_bit_floor_ull", RetValSpec<UnsignedLongLongType>, [ArgSpec<UnsignedLongLongType>]>,
+          FunctionSpec<"stdc_bit_ceil_uc", RetValSpec<UnsignedCharType>, [ArgSpec<UnsignedCharType>]>,
+          FunctionSpec<"stdc_bit_ceil_us", RetValSpec<UnsignedShortType>, [ArgSpec<UnsignedShortType>]>,
+          FunctionSpec<"stdc_bit_ceil_ui", RetValSpec<UnsignedIntType>, [ArgSpec<UnsignedIntType>]>,
+          FunctionSpec<"stdc_bit_ceil_ul", RetValSpec<UnsignedLongType>, [ArgSpec<UnsignedLongType>]>,
+          FunctionSpec<"stdc_bit_ceil_ull", RetValSpec<UnsignedLongLongType>, [ArgSpec<UnsignedLongLongType>]>
       ] // Functions
   >;
 

libc/src/__support/CPP/bit.h

@@ -193,7 +193,7 @@ template <typename T>
 bit_ceil(T value) {
   if (value < 2)
     return 1;
-  return T(1) << cpp::bit_width<T>(value - 1u);
+  return static_cast<T>(T(1) << cpp::bit_width<T>(value - 1u));
 }
 
 // Rotate algorithms make use of "Safe, Efficient, and Portable Rotate in C/C++"

libc/src/stdbit/CMakeLists.txt

@@ -12,6 +12,7 @@ set(prefixes
   has_single_bit
   bit_width
   bit_floor
+  bit_ceil
 )
 set(suffixes c s i l ll)
 foreach(prefix IN LISTS prefixes)

libc/src/stdbit/stdc_bit_ceil_uc.cpp

@@ -0,0 +1,20 @@
+//===-- Implementation of stdc_bit_ceil_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_bit_ceil_uc.h"
+
+#include "src/__support/CPP/bit.h"
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(unsigned char, stdc_bit_ceil_uc, (unsigned char value)) {
+  return cpp::bit_ceil(value);
+}
+
+} // namespace LIBC_NAMESPACE

libc/src/stdbit/stdc_bit_ceil_uc.h

@@ -0,0 +1,18 @@
+//===-- Implementation header for stdc_bit_ceil_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_BIT_CEIL_UC_H
+#define LLVM_LIBC_SRC_STDBIT_STDC_BIT_CEIL_UC_H
+
+namespace LIBC_NAMESPACE {
+
+unsigned char stdc_bit_ceil_uc(unsigned char value);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_STDBIT_STDC_BIT_CEIL_UC_H

libc/src/stdbit/stdc_bit_ceil_ui.cpp

@@ -0,0 +1,20 @@
+//===-- Implementation of stdc_bit_ceil_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_bit_ceil_ui.h"
+
+#include "src/__support/CPP/bit.h"
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(unsigned, stdc_bit_ceil_ui, (unsigned value)) {
+  return cpp::bit_ceil(value);
+}
+
+} // namespace LIBC_NAMESPACE

libc/src/stdbit/stdc_bit_ceil_ui.h

@@ -0,0 +1,18 @@
+//===-- Implementation header for stdc_bit_ceil_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_BIT_CEIL_UI_H
+#define LLVM_LIBC_SRC_STDBIT_STDC_BIT_CEIL_UI_H
+
+namespace LIBC_NAMESPACE {
+
+unsigned stdc_bit_ceil_ui(unsigned value);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_STDBIT_STDC_BIT_CEIL_UI_H

libc/src/stdbit/stdc_bit_ceil_ul.cpp

@@ -0,0 +1,20 @@
+//===-- Implementation of stdc_bit_ceil_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_bit_ceil_ul.h"
+
+#include "src/__support/CPP/bit.h"
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(unsigned long, stdc_bit_ceil_ul, (unsigned long value)) {
+  return cpp::bit_ceil(value);
+}
+
+} // namespace LIBC_NAMESPACE

libc/src/stdbit/stdc_bit_ceil_ul.h

@@ -0,0 +1,18 @@
+//===-- Implementation header for stdc_bit_ceil_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_BIT_CEIL_UL_H
+#define LLVM_LIBC_SRC_STDBIT_STDC_BIT_CEIL_UL_H
+
+namespace LIBC_NAMESPACE {
+
+unsigned long stdc_bit_ceil_ul(unsigned long value);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_STDBIT_STDC_BIT_CEIL_UL_H

libc/src/stdbit/stdc_bit_ceil_ull.cpp

@@ -0,0 +1,21 @@
+//===-- Implementation of stdc_bit_ceil_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_bit_ceil_ull.h"
+
+#include "src/__support/CPP/bit.h"
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(unsigned long long, stdc_bit_ceil_ull,
+                   (unsigned long long value)) {
+  return cpp::bit_ceil(value);
+}
+
+} // namespace LIBC_NAMESPACE

libc/src/stdbit/stdc_bit_ceil_ull.h

@@ -0,0 +1,18 @@
+//===-- Implementation header for stdc_bit_ceil_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_BIT_CEIL_ULL_H
+#define LLVM_LIBC_SRC_STDBIT_STDC_BIT_CEIL_ULL_H
+
+namespace LIBC_NAMESPACE {
+
+unsigned long long stdc_bit_ceil_ull(unsigned long long value);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_STDBIT_STDC_BIT_CEIL_ULL_H

libc/src/stdbit/stdc_bit_ceil_us.cpp

@@ -0,0 +1,20 @@
+//===-- Implementation of stdc_bit_ceil_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_bit_ceil_us.h"
+
+#include "src/__support/CPP/bit.h"
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(unsigned short, stdc_bit_ceil_us, (unsigned short value)) {
+  return cpp::bit_ceil(value);
+}
+
+} // namespace LIBC_NAMESPACE

libc/src/stdbit/stdc_bit_ceil_us.h

@@ -0,0 +1,18 @@
+//===-- Implementation header for stdc_bit_ceil_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_BIT_CEIL_US_H
+#define LLVM_LIBC_SRC_STDBIT_STDC_BIT_CEIL_US_H
+
+namespace LIBC_NAMESPACE {
+
+unsigned short stdc_bit_ceil_us(unsigned short value);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_STDBIT_STDC_BIT_CEIL_US_H

libc/test/include/stdbit_test.cpp

@@ -98,6 +98,13 @@ unsigned long stdc_bit_floor_ul(unsigned long) noexcept { return 0x5DU; }
 unsigned long long stdc_bit_floor_ull(unsigned long long) noexcept {
   return 0x5EU;
 }
+unsigned char stdc_bit_ceil_uc(unsigned char) noexcept { return 0x6AU; }
+unsigned short stdc_bit_ceil_us(unsigned short) noexcept { return 0x6BU; }
+unsigned stdc_bit_ceil_ui(unsigned) noexcept { return 0x6CU; }
+unsigned long stdc_bit_ceil_ul(unsigned long) noexcept { return 0x6DU; }
+unsigned long long stdc_bit_ceil_ull(unsigned long long) noexcept {
+  return 0x6EU;
+}
 }
 
 #include "include/llvm-libc-macros/stdbit-macros.h"
@@ -207,3 +214,13 @@ TEST(LlvmLibcStdbitTest, TypeGenericMacroBitFloor) {
   EXPECT_EQ(stdc_bit_floor(0UL), 0x5DUL);
   EXPECT_EQ(stdc_bit_floor(0ULL), 0x5EULL);
 }
+
+TEST(LlvmLibcStdbitTest, TypeGenericMacroBitCeil) {
+  EXPECT_EQ(stdc_bit_ceil(static_cast<unsigned char>(0U)),
+            static_cast<unsigned char>(0x6AU));
+  EXPECT_EQ(stdc_bit_ceil(static_cast<unsigned short>(0U)),
+            static_cast<unsigned short>(0x6BU));
+  EXPECT_EQ(stdc_bit_ceil(0U), 0x6CU);
+  EXPECT_EQ(stdc_bit_ceil(0UL), 0x6DUL);
+  EXPECT_EQ(stdc_bit_ceil(0ULL), 0x6EULL);
+}

libc/test/src/stdbit/CMakeLists.txt

@@ -14,6 +14,7 @@ set(prefixes
   has_single_bit
   bit_width
   bit_floor
+  bit_ceil
 )
 set(suffixes c s i l ll)
 foreach(prefix IN LISTS prefixes)

libc/test/src/stdbit/stdc_bit_ceil_uc_test.cpp

@@ -0,0 +1,34 @@
+//===-- Unittests for stdc_bit_ceil_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_bit_ceil_uc.h"
+#include "test/UnitTest/Test.h"
+
+TEST(LlvmLibcStdcBitceilUcTest, Zero) {
+  EXPECT_EQ(LIBC_NAMESPACE::stdc_bit_ceil_uc(0U),
+            static_cast<unsigned char>(1));
+}
+
+TEST(LlvmLibcStdcBitceilUcTest, Ones) {
+  for (unsigned i = 0U; i != UCHAR_WIDTH; ++i)
+    EXPECT_EQ(LIBC_NAMESPACE::stdc_bit_ceil_uc(1U << i),
+              static_cast<unsigned char>(1U << i));
+}
+
+TEST(LlvmLibcStdcBitceilUcTest, OneLessThanPowsTwo) {
+  for (unsigned i = 2U; i != UCHAR_WIDTH; ++i)
+    EXPECT_EQ(LIBC_NAMESPACE::stdc_bit_ceil_uc((1U << i) - 1),
+              static_cast<unsigned char>(1U << i));
+}
+
+TEST(LlvmLibcStdcBitceilUcTest, OneMoreThanPowsTwo) {
+  for (unsigned i = 1U; i != UCHAR_WIDTH - 1; ++i)
+    EXPECT_EQ(LIBC_NAMESPACE::stdc_bit_ceil_uc((1U << i) + 1),
+              static_cast<unsigned char>(1U << (i + 1)));
+}