From d99afc1b374cd13e00113de238439583531d7804 Mon Sep 17 00:00:00 2001
From: Robert Clausecker <fuz@FreeBSD.org>
Date: Mon, 22 May 2023 14:33:20 +0200
Subject: [PATCH] Cpu: implement ARM feature detection on FreeBSD.

---
 src/Corrade/Cpu.cpp | 12 +++++++++---
 src/Corrade/Cpu.h   |  8 ++++----
 2 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/src/Corrade/Cpu.cpp b/src/Corrade/Cpu.cpp
index 548c2b664..914eb1a4f 100644
--- a/src/Corrade/Cpu.cpp
+++ b/src/Corrade/Cpu.cpp
@@ -33,8 +33,8 @@
 
 /** @todo these are indented to work around acme.py extracting them to the top,
     fix properly */
-/* getauxval() for ARM on Linux and Android with API level 18+ */
-#if defined(CORRADE_TARGET_ARM) && defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)
+/* getauxval() for ARM on Linux, Android with API level 18+ and FreeBSD */
+#if defined(CORRADE_TARGET_ARM) && ((defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)) || defined(__FreeBSD__))
     #include <sys/auxv.h>
 /* sysctlbyname() for ARM on macOS / iOS */
 #elif defined(CORRADE_TARGET_ARM) && defined(CORRADE_TARGET_APPLE)
@@ -80,7 +80,7 @@ int appleSysctlByName(const char* name) {
 }
 #endif
 
-#if defined(CORRADE_TARGET_ARM) && ((defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)) || defined(CORRADE_TARGET_APPLE))
+#if defined(CORRADE_TARGET_ARM) && ((defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)) || defined(CORRADE_TARGET_APPLE) || defined(__FreeBSD__))
 Features runtimeFeatures() {
     /* Use getauxval() on ARM on Linux and Android */
     #if defined(CORRADE_TARGET_ARM) && defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)
@@ -127,6 +127,12 @@ Features runtimeFeatures() {
 
     return Features{out};
 
+    /* Use elf_aux_info() on ARM on FreeBSD */
+    #elif defined(CORRADE_TARGET_ARM) && defined(__FreeBSD__)
+    unsigned long hwcap = 0;
+    elf_aux_info(AT_HWCAP, &hwcap, sizeof(hwcap));
+    return Implementation::runtimeFeatures(hwcap);
+
     /* No other (deinlined) implementation at the moment. The function should
        not be even defined here in that case -- it's inlined in the header
        instead, including the x86 implementation. */
diff --git a/src/Corrade/Cpu.h b/src/Corrade/Cpu.h
index 3e6a7808c..64640a4a7 100644
--- a/src/Corrade/Cpu.h
+++ b/src/Corrade/Cpu.h
@@ -1400,7 +1400,7 @@ Returns a tag corresponding to tag type @p T. The following two expressions are
 */
 template<class T> constexpr T tag() { return T{Implementation::Init}; }
 
-#if defined(CORRADE_TARGET_ARM) && defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)
+#if defined(CORRADE_TARGET_ARM) && ((defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)) || defined(__FreeBSD__))
 namespace Implementation {
     /* Needed for a friend declaration, implementation is at the very end of
        the header */
@@ -1539,7 +1539,7 @@ class Features {
         #endif
         Features runtimeFeatures();
         #endif
-        #if defined(CORRADE_TARGET_ARM) && defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)
+        #if defined(CORRADE_TARGET_ARM) && ((defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)) || defined(__FreeBSD__))
         friend Features Implementation::runtimeFeatures(unsigned long);
         #endif
 
@@ -1846,7 +1846,7 @@ value is equal to @ref Scalar, which in turn is equivalent to empty (or
 default-constructed) @ref Features.
 @see @ref DefaultBase, @ref DefaultExtra, @ref Default
 */
-#if (defined(CORRADE_TARGET_X86) && (defined(CORRADE_TARGET_MSVC) || defined(CORRADE_TARGET_GCC))) || (defined(CORRADE_TARGET_ARM) && ((defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)) || defined(CORRADE_TARGET_APPLE))) || defined(DOXYGEN_GENERATING_OUTPUT)
+#if (defined(CORRADE_TARGET_X86) && (defined(CORRADE_TARGET_MSVC) || defined(CORRADE_TARGET_GCC))) || (defined(CORRADE_TARGET_ARM) && ((defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)) || defined(CORRADE_TARGET_APPLE) || defined(__FreeBSD__))) || defined(DOXYGEN_GENERATING_OUTPUT)
 #ifdef CORRADE_TARGET_ARM
 CORRADE_UTILITY_EXPORT /* Inlined on x86 at the very end of the header */
 #endif
@@ -3349,7 +3349,7 @@ inline Features runtimeFeatures() {
 /** @todo If AT_HWCAP2 or other bits are needed, it's passed to ifunc resolvers
     only since glibc 2.30 (and Android API 30+, which is the same as before):
     https://github.com/bminor/glibc/commit/2b8a3c86e7606cf1b0a997dad8af2d45ae8989c3 */
-#if defined(CORRADE_TARGET_ARM) && defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)
+#if defined(CORRADE_TARGET_ARM) && ((defined(__linux__) && !(defined(CORRADE_TARGET_ANDROID) && __ANDROID_API__ < 18)) || defined(__FreeBSD__))
 namespace Implementation {
     inline Features runtimeFeatures(const unsigned long caps) {
         unsigned int out = 0;