AK+Everywhere: Replace __builtin bit functions

In order to reduce our reliance on __builtin_{ffs, clz, ctz, popcount},
this commit removes all calls to these functions and replaces them with
the equivalent functions in AK/BuiltinWrappers.h.

Userland/DevTools/UserspaceEmulator/SoftCPU.cpp

@@ -8,6 +8,7 @@
 #include "SoftCPU.h"
 #include "Emulator.h"
 #include <AK/Assertions.h>
+#include <AK/BuiltinWrappers.h>
 #include <AK/Debug.h>
 #include <stdio.h>
 #include <string.h>
@@ -978,7 +979,7 @@ void SoftCPU::BOUND(const X86::Instruction&) { TODO_INSN(); }
 template<typename T>
 ALWAYS_INLINE static T op_bsf(SoftCPU&, T value)
 {
-    return { (typename T::ValueType)__builtin_ctz(value.value()), value.shadow() };
+    return { (typename T::ValueType)bit_scan_forward(value.value()), value.shadow() };
 }
 
 template<typename T>

Userland/Libraries/LibC/malloc.cpp

@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <AK/BuiltinWrappers.h>
 #include <AK/Debug.h>
 #include <AK/ScopedValueRollback.h>
 #include <AK/Vector.h>
@@ -437,7 +438,7 @@ void* malloc(size_t size)
 // _aligned_free(), so it can be easily implemented on top of malloc().
 void* _aligned_malloc(size_t size, size_t alignment)
 {
-    if (__builtin_popcount(alignment) != 1) {
+    if (popcount(alignment) != 1) {
         errno = EINVAL;
         return nullptr;
     }

Userland/Libraries/LibCrypto/BigInt/Algorithms/BitwiseOperations.cpp

@@ -6,6 +6,7 @@
  */
 
 #include "UnsignedBigIntegerAlgorithms.h"
+#include <AK/BuiltinWrappers.h>
 
 namespace Crypto {
 
@@ -153,7 +154,7 @@ FLATTEN void UnsignedBigIntegerAlgorithms::bitwise_not_without_allocation(
     auto last_word_index = right.length() - 1;
     auto last_word = right.words()[last_word_index];
 
-    output.m_words[last_word_index] = ((u32)0xffffffffffffffff >> __builtin_clz(last_word)) & ~last_word;
+    output.m_words[last_word_index] = ((u32)0xffffffffffffffff >> count_leading_zeroes(last_word)) & ~last_word;
 }
 
 /**

Userland/Libraries/LibGfx/BMPLoader.cpp

@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <AK/BuiltinWrappers.h>
 #include <AK/Debug.h>
 #include <AK/Function.h>
 #include <AK/String.h>
@@ -326,9 +327,9 @@ static void populate_dib_mask_info_if_needed(BMPLoadingContext& context)
             mask_sizes.append(0);
             continue;
         }
-        int trailing_zeros = count_trailing_zeroes_32(mask);
+        int trailing_zeros = count_trailing_zeroes(mask);
         // If mask is exactly `0xFFFFFFFF`, then we might try to count the trailing zeros of 0x00000000 here, so we need the safe version:
-        int size = count_trailing_zeroes_32_safe(~(mask >> trailing_zeros));
+        int size = count_trailing_zeroes_safe(~(mask >> trailing_zeros));
         if (size > 8) {
             // Drop lowest bits if mask is longer than 8 bits.
             trailing_zeros += size - 8;

Userland/Libraries/LibGfx/BitmapFont.cpp

@@ -6,6 +6,7 @@
 
 #include "BitmapFont.h"
 #include "Emoji.h"
+#include <AK/BuiltinWrappers.h>
 #include <AK/Utf32View.h>
 #include <AK/Utf8View.h>
 #include <LibCore/FileStream.h>
@@ -95,7 +96,7 @@ NonnullRefPtr<BitmapFont> BitmapFont::masked_character_set() const
     }
     size_t new_glyph_count { 0 };
     for (size_t i = 0; i < new_range_mask_size; ++i) {
-        new_glyph_count += 256 * __builtin_popcount(new_range_mask[i]);
+        new_glyph_count += 256 * popcount(new_range_mask[i]);
     }
     size_t bytes_per_glyph = sizeof(u32) * m_glyph_height;
     auto* new_rows = static_cast<u8*>(calloc(new_glyph_count, bytes_per_glyph));
@@ -191,7 +192,7 @@ RefPtr<BitmapFont> BitmapFont::load_from_memory(const u8* data)
     size_t glyph_count { 0 };
     u8* range_mask = const_cast<u8*>(data + sizeof(FontFileHeader));
     for (size_t i = 0; i < header.range_mask_size; ++i)
-        glyph_count += 256 * __builtin_popcount(range_mask[i]);
+        glyph_count += 256 * popcount(range_mask[i]);
     u8* rows = range_mask + header.range_mask_size;
     u8* widths = (u8*)(rows) + glyph_count * bytes_per_glyph;
     return adopt_ref(*new BitmapFont(String(header.name), String(header.family), rows, widths, !header.is_variable_width, header.glyph_width, header.glyph_height, header.glyph_spacing, header.range_mask_size, range_mask, header.baseline, header.mean_line, header.presentation_size, header.weight, header.slope));

Userland/Libraries/LibJS/Runtime/GlobalObject.cpp

@@ -5,6 +5,7 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <AK/BuiltinWrappers.h>
 #include <AK/CharacterTypes.h>
 #include <AK/Hex.h>
 #include <AK/Platform.h>
@@ -500,7 +501,7 @@ static ThrowCompletionOr<String> decode(JS::GlobalObject& global_object, const S
             continue;
         }
 
-        auto leading_ones = count_trailing_zeroes_32_safe(~decoded_code_unit) - 24;
+        auto leading_ones = count_trailing_zeroes_safe(static_cast<u32>(~decoded_code_unit)) - 24;
         if (leading_ones == 1 || leading_ones > 4)
             return global_object.vm().throw_completion<URIError>(global_object, ErrorType::URIMalformed);
 

Userland/Libraries/LibJS/Runtime/MathObject.cpp

@@ -6,6 +6,7 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <AK/BuiltinWrappers.h>
 #include <AK/Function.h>
 #include <AK/Random.h>
 #include <LibJS/Runtime/GlobalObject.h>
@@ -303,7 +304,7 @@ JS_DEFINE_NATIVE_FUNCTION(MathObject::clz32)
     auto number = TRY(vm.argument(0).to_u32(global_object));
     if (number == 0)
         return Value(32);
-    return Value(__builtin_clz(number));
+    return Value(count_leading_zeroes(number));
 }
 
 // 21.3.2.2 Math.acos ( x ), https://tc39.es/ecma262/#sec-math.acos

Userland/Libraries/LibM/math.cpp

@@ -5,6 +5,7 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <AK/BuiltinWrappers.h>
 #include <AK/ExtraMathConstants.h>
 #include <AK/Math.h>
 #include <AK/Platform.h>
@@ -278,7 +279,7 @@ static FloatT internal_scalbn(FloatT x, int exponent) NOEXCEPT
         return extractor.d;
     }
 
-    unsigned leading_mantissa_zeroes = extractor.mantissa == 0 ? 32 : __builtin_clz(extractor.mantissa);
+    unsigned leading_mantissa_zeroes = extractor.mantissa == 0 ? 32 : count_leading_zeroes(extractor.mantissa);
     int shift = min((int)leading_mantissa_zeroes, exponent);
     exponent = max(exponent - shift, 0);
 

Userland/Libraries/LibWasm/AbstractMachine/Operators.h

@@ -7,6 +7,7 @@
 #pragma once
 
 #include <AK/BitCast.h>
+#include <AK/BuiltinWrappers.h>
 #include <AK/Result.h>
 #include <AK/StringView.h>
 #include <AK/Types.h>
@@ -176,10 +177,8 @@ struct CountLeadingZeros {
         if (lhs == 0)
             return sizeof(Lhs) * CHAR_BIT;
 
-        if constexpr (sizeof(Lhs) == 4)
-            return __builtin_clz(lhs);
-        else if constexpr (sizeof(Lhs) == 8)
-            return __builtin_clzll(lhs);
+        if constexpr (sizeof(Lhs) == 4 || sizeof(Lhs) == 8)
+            return count_leading_zeroes(MakeUnsigned<Lhs>(lhs));
         else
             VERIFY_NOT_REACHED();
     }
@@ -193,10 +192,8 @@ struct CountTrailingZeros {
         if (lhs == 0)
             return sizeof(Lhs) * CHAR_BIT;
 
-        if constexpr (sizeof(Lhs) == 4)
-            return __builtin_ctz(lhs);
-        else if constexpr (sizeof(Lhs) == 8)
-            return __builtin_ctzll(lhs);
+        if constexpr (sizeof(Lhs) == 4 || sizeof(Lhs) == 8)
+            return count_trailing_zeroes(MakeUnsigned<Lhs>(lhs));
         else
             VERIFY_NOT_REACHED();
     }
@@ -207,10 +204,8 @@ struct PopCount {
     template<typename Lhs>
     auto operator()(Lhs lhs) const
     {
-        if constexpr (sizeof(Lhs) == 4)
-            return __builtin_popcount(lhs);
-        else if constexpr (sizeof(Lhs) == 8)
-            return __builtin_popcountll(lhs);
+        if constexpr (sizeof(Lhs) == 4 || sizeof(Lhs) == 8)
+            return popcount(MakeUnsigned<Lhs>(lhs));
         else
             VERIFY_NOT_REACHED();
     }