Split implementation

Author: AntoinePrv

include/xsimd/config/xsimd_cpu_features_arm.hpp

@@ -37,45 +37,51 @@ namespace xsimd
     class arm_cpu_features : private linux_hwcap_backend_default
     {
     public:
-        arm_cpu_features() noexcept = default;
+        inline bool neon() const noexcept;
+        inline bool neon64() const noexcept;
+        inline bool sve() const noexcept;
+        inline bool i8mm() const noexcept;
+    };
+
+    /********************
+     *  Implementation  *
+     ********************/
 
-        inline bool neon() const noexcept
-        {
+    inline bool arm_cpu_features::neon() const noexcept
+    {
 #if XSIMD_TARGET_ARM && !XSIMD_TARGET_ARM64 && XSIMD_HAVE_LINUX_GETAUXVAL
-            return hwcap().has_feature(HWCAP_NEON);
+        return hwcap().has_feature(HWCAP_NEON);
 #else
-            return static_cast<bool>(XSIMD_WITH_NEON);
+        return static_cast<bool>(XSIMD_WITH_NEON);
 #endif
-        }
+    }
 
-        constexpr bool neon64() const noexcept
-        {
-            return static_cast<bool>(XSIMD_WITH_NEON64);
-        }
+    inline bool arm_cpu_features::neon64() const noexcept
+    {
+        return static_cast<bool>(XSIMD_WITH_NEON64);
+    }
 
-        inline bool sve() const noexcept
-        {
+    inline bool arm_cpu_features::sve() const noexcept
+    {
 #if XSIMD_TARGET_ARM64 && XSIMD_HAVE_LINUX_GETAUXVAL
-            return hwcap().has_feature(HWCAP_SVE);
+        return hwcap().has_feature(HWCAP_SVE);
 #else
-            return false;
+        return false;
 #endif
-        }
-
-        inline bool i8mm() const noexcept
-        {
+    }
 
+    inline bool arm_cpu_features::i8mm() const noexcept
+    {
 #if XSIMD_TARGET_ARM64 && XSIMD_HAVE_LINUX_GETAUXVAL
 #ifdef HWCAP2_I8MM
-            return hwcap2().has_feature(HWCAP2_I8MM);
+        return hwcap2().has_feature(HWCAP2_I8MM);
 #else
-            // Possibly missing on older Linux distributions
-            return hwcap2().has_feature(1 << 13);
+        // Possibly missing on older Linux distributions
+        return hwcap2().has_feature(1 << 13);
 #endif
 #else
-            return false;
+        return false;
 #endif
-        }
-    };
+    }
 }
 #endif

include/xsimd/config/xsimd_cpu_features_riscv.hpp

@@ -27,22 +27,26 @@ namespace xsimd
     class riscv_cpu_features : private linux_hwcap_backend_default
     {
     public:
-        riscv_cpu_features() noexcept = default;
+        inline bool rvv() const noexcept;
+    };
+
+    /********************
+     *  Implementation  *
+     ********************/
 
-        inline bool rvv() const noexcept
-        {
+    inline bool riscv_cpu_features::rvv() const noexcept
+    {
 #if XSIMD_TARGET_RISCV && XSIMD_HAVE_LINUX_GETAUXVAL
 #ifdef HWCAP_V
-            return hwcap().has_feature(HWCAP_V);
+        return hwcap().has_feature(HWCAP_V);
 #else
-            // Possibly missing on older Linux distributions
-            return hwcap().has_feature(1 << ('V' - 'A'));
+        // Possibly missing on older Linux distributions
+        return hwcap().has_feature(1 << ('V' - 'A'));
 #endif
 #else
-            return false;
+        return false;
 #endif
-        }
-    };
+    }
 }
 
 #endif

include/xsimd/config/xsimd_getauxval.hpp

@@ -69,7 +69,7 @@ namespace xsimd
         }
     };
 
-    class linux_hwcap_backend_full
+    class linux_hwcap_backend
     {
     public:
         inline linux_auxval hwcap() const noexcept;
@@ -99,9 +99,17 @@ namespace xsimd
     };
 
 #if XSIMD_HAVE_LINUX_GETAUXVAL
-    using linux_hwcap_backend_default = linux_hwcap_backend_full;
+    using linux_hwcap_backend_default = linux_hwcap_backend;
 #else
-    using linux_hwcap_backend_default = linux_hwcap_backend_noop;
+    // Contrary to CPUID that is only used on one architecture, HWCAP are
+    // available on multiple architectures with different meaning for the
+    // different bit fields.
+    // We use the Linux `HWCAP` constants directly to avoid repetition, so
+    // we could not use a default implementation without already being on
+    // Linux anyways.
+    struct linux_hwcap_backend_default
+    {
+    };
 #endif
 
     /********************
@@ -123,7 +131,7 @@ namespace xsimd
 #endif
     }
 
-    inline linux_auxval linux_hwcap_backend_full::hwcap() const noexcept
+    inline linux_auxval linux_hwcap_backend::hwcap() const noexcept
     {
         if (!m_status.bit_is_set<status::hwcap_valid>())
         {
@@ -135,7 +143,7 @@ namespace xsimd
         return m_hwcap;
     }
 
-    inline linux_auxval linux_hwcap_backend_full::hwcap2() const noexcept
+    inline linux_auxval linux_hwcap_backend::hwcap2() const noexcept
     {
         if (!m_status.bit_is_set<status::hwcap2_valid>())
         {