singles: new CorradeCpu library.

doc/corrade-singles.dox

@@ -53,6 +53,7 @@ Class, library or header    | Single-header version
 @ref Containers::Pointer    | [CorradePointer.h](https://github.com/mosra/magnum-singles/tree/master/CorradePointer.h)
 @ref Containers::Reference  | [CorradeReference.h](https://github.com/mosra/magnum-singles/tree/master/CorradeReference.h)
 @ref Containers::ScopeGuard | [CorradeScopeGuard.h](https://github.com/mosra/magnum-singles/tree/master/CorradeScopeGuard.h)
+@ref Corrade::Cpu           | [CorradeCpu.h](https://github.com/mosra/magnum-singles/tree/master/CorradeCpu.h)
 @ref Corrade/Utility/StlForwardArray.h | [CorradeStlForwardArray.h](https://github.com/mosra/magnum-singles/tree/master/CorradeStlForwardArray.h)
 @ref Corrade/Utility/StlForwardString.h | [CorradeStlForwardString.h](https://github.com/mosra/magnum-singles/tree/master/CorradeStlForwardString.h)
 @ref Corrade/Utility/StlForwardTuple.h | [CorradeStlForwardTuple.h](https://github.com/mosra/magnum-singles/tree/master/CorradeStlForwardTuple.h)

src/Corrade/Cpu.h

@@ -74,6 +74,10 @@ find_package(Corrade REQUIRED Utility)
 target_link_libraries(your-app PRIVATE Corrade::Utility)
 @endcode
 
+This namespace together with all related macros is additionally available in a
+form of a @ref Cpu-single-header "single-header library". See also
+@ref building-corrade and @ref corrade-cmake for more information.
+
 @section Cpu-usage Usage
 
 The @ref Cpu namespace contains tags such as @ref Cpu::Avx2, @ref Cpu::Sse2,
@@ -397,6 +401,32 @@ Finally, when exposed in a header as appropriate, both the function and the
 function pointer variant can be then called the same way:
 
 @snippet Corrade.cpp Cpu-usage-automatic-cached-dispatch-call
+
+@anchor Cpu-single-header
+
+<b></b>
+
+@m_class{m-block m-success}
+
+@par Single-header version
+    This namespace together with all related macros is also available as a
+    single-header, dependency-less [CorradeCpu.h](https://github.com/mosra/magnum-singles/tree/master/CorradeCpu.h)
+    library in the Magnum Singles repository for easier integration into your
+    projects. See @ref corrade-singles for more information.
+@par
+    To avoid bloat from OS-specific headers, this library contains a deinlined
+    implementation part, in particular for runtime feature detection on ARM.
+    Dedicate *exactly one* file in your project and add the following to it:
+@par
+    @code{.cpp}
+    #define CORRADE_CPU_IMPLEMENTATION
+    #include "CorradeCpu.h"
+    @endcode
+@par
+    If you need the deinlined symbols to be exported from a shared library,
+    @cpp #define CORRADE_UTILITY_EXPORT @ce as appropriate. To enable the
+    IFUNC functionality, @cpp #define CORRADE_CPU_USE_IFUNC @ce before
+    including the file.
 */
 namespace Cpu {
 

src/singles/CorradeCpu.h

@@ -0,0 +1,88 @@
+/*
+    Corrade::Cpu
+        — compile-time and runtime CPU feature detection and dispatch
+
+    https://doc.magnum.graphics/corrade/namespaceCorrade_1_1Cpu.html
+
+    This is a single-header library generated from the Corrade project. With
+    the goal being easy integration, it's deliberately free of all comments
+    to keep the file size small. More info, detailed changelogs and docs here:
+
+    -   Project homepage — https://magnum.graphics/corrade/
+    -   Documentation — https://doc.magnum.graphics/corrade/
+    -   GitHub project page — https://github.com/mosra/corrade
+    -   GitHub Singles repository — https://github.com/mosra/magnum-singles
+
+    To avoid bloat from OS-specific headers, this library contains a deinlined
+    implementation part, in particular for runtime feature detection on ARM.
+    Dedicate *exactly one* file in your project and add the following to it:
+
+        #define CORRADE_CPU_IMPLEMENTATION
+        #include "CorradeCpu.h"
+
+    If you need the deinlined symbols to be exported from a shared library,
+    #define CORRADE_UTILITY_EXPORT as appropriate. To enable the IFUNC
+    functionality, #define CORRADE_CPU_USE_IFUNC before including the file.
+
+    v2020.06-1015-g8cbd6 (2022-08-02)
+    -   Initial release
+
+    Generated from Corrade {{revision}}, {{stats:loc}} / {{stats:preprocessed}} LoC
+*/
+
+#include "base.h"
+
+/* Detect platforms based on preprocessor defines. Corrade itself does that
+   through CMake and bakes that into configure.h, which we can't do here. */
+/* https://stackoverflow.com/a/8249232 */
+#ifdef __ANDROID__
+#define CORRADE_TARGET_ANDROID
+#endif
+/* https://stackoverflow.com/a/41508246 */
+#ifdef __EMSCRIPTEN__
+#define CORRADE_TARGET_EMSCRIPTEN
+#endif
+/* https://stackoverflow.com/a/8249232 */
+#ifdef __APPLE__
+#define CORRADE_TARGET_APPLE
+#endif
+
+/* Supply the configure.h template instead to avoid using baked-in defines */
+#include "Corrade/configure.h.cmake"
+#pragma ACME enable Corrade_configure_h
+
+/* Contains just Cpu::Features forward declaration, which we don't need */
+#pragma ACME enable Corrade_Corrade_h
+
+/* We need just the INLINE macros and _CORRADE_HELPER_PASTE2 */
+#pragma ACME enable Corrade_Utility_Macros_h
+#ifndef CorradeCpu_h
+#define CorradeCpu_h
+#ifdef CORRADE_TARGET_GCC
+#define CORRADE_ALWAYS_INLINE __attribute__((always_inline)) inline
+#elif defined(CORRADE_TARGET_MSVC)
+#define CORRADE_ALWAYS_INLINE __forceinline
+#else
+#define CORRADE_ALWAYS_INLINE inline
+#endif
+
+#ifdef CORRADE_TARGET_GCC
+#define CORRADE_NEVER_INLINE __attribute__((noinline))
+#elif defined(CORRADE_TARGET_MSVC)
+#define CORRADE_NEVER_INLINE __declspec(noinline)
+#else
+#define CORRADE_NEVER_INLINE
+#endif
+
+#define _CORRADE_HELPER_PASTE2(a, b) a ## b
+
+/* For the deinlined runtimeFeatures() implementation on ARM */
+#ifndef CORRADE_UTILITY_EXPORT
+#define CORRADE_UTILITY_EXPORT
+#endif
+#endif
+#include "Corrade/Cpu.h"
+#ifdef CORRADE_CPU_IMPLEMENTATION
+// {{includes}}
+#include "Corrade/Cpu.cpp"
+#endif

src/singles/generate.sh

@@ -13,3 +13,5 @@ set -e
 ../acme/acme.py CorradeStlForwardTuple.h --output ../../../magnum-singles
 ../acme/acme.py CorradeStlForwardVector.h --output ../../../magnum-singles
 ../acme/acme.py CorradeStlMath.h --output ../../../magnum-singles
+
+../acme/acme.py CorradeCpu.h --output ../../../magnum-singles