Updated platform bit utilities

7 files changed, 129 insertions, 45 deletions

diff --git a/Platforms/Android/include/AndroidPlatformMisc.h b/Platforms/Android/include/AndroidPlatformMisc.h
index 1be455c8..4ccb0bb6 100644
--- a/Platforms/Android/include/AndroidPlatformMisc.h
+++ b/Platforms/Android/include/AndroidPlatformMisc.h
@@ -25,19 +25,9 @@
 
 #include "../../Basic/interface/BasicPlatformMisc.h"
 #include "../../../Platforms/Basic/interface/DebugUtilities.h"
+#include "../../Linux/include/LinuxPlatformMisc.h"
 
-struct AndroidMisc : public BasicPlatformMisc
+struct AndroidMisc : public LinuxMisc
 {
-    static Diligent::Uint32 GetMSB(Diligent::Uint32 Val)
-    {
-        if( Val == 0 )return 32;
 
-        // Returns the number of leading 0-bits in x, starting at the 
-        // most significant bit position. If x is 0, the result is undefined.
-        auto LeadingZeros = __builtin_clz(Val);
-        auto MSB = 31 - LeadingZeros;
-        VERIFY_EXPR(MSB == BasicPlatformMisc::GetMSB(Val));
-
-        return MSB;
-    }
 };
diff --git a/Platforms/Apple/include/ApplePlatformMisc.h b/Platforms/Apple/include/ApplePlatformMisc.h
index b1b22556..ca753feb 100644
--- a/Platforms/Apple/include/ApplePlatformMisc.h
+++ b/Platforms/Apple/include/ApplePlatformMisc.h
@@ -25,19 +25,9 @@
 
 #include "../../Basic/interface/BasicPlatformMisc.h"
 #include "../../../Platforms/Basic/interface/DebugUtilities.h"
+#include "../../Linux/include/LinuxPlatformMisc.h"
 
-struct AppleMisc : public BasicPlatformMisc
+struct AppleMisc : public LinuxMisc
 {
-    static Diligent::Uint32 GetMSB(Diligent::Uint32 Val)
-    {
-        if( Val == 0 )return 32;
 
-        // Returns the number of leading 0-bits in x, starting at the 
-        // most significant bit position. If x is 0, the result is undefined.
-        auto LeadingZeros = __builtin_clz(Val);
-        auto MSB = 31 - LeadingZeros;
-        VERIFY_EXPR(MSB == BasicPlatformMisc::GetMSB(Val));
-
-        return MSB;
-    }
 };
diff --git a/Platforms/Basic/interface/BasicPlatformMisc.h b/Platforms/Basic/interface/BasicPlatformMisc.h
index 023ec65d..c93497b3 100644
--- a/Platforms/Basic/interface/BasicPlatformMisc.h
+++ b/Platforms/Basic/interface/BasicPlatformMisc.h
@@ -27,25 +27,39 @@
 
 struct BasicPlatformMisc
 {
-    static Diligent::Uint32 GetMSB(Diligent::Uint32 Val)
+    template<typename Type>
+    static Diligent::Uint32 GetMSB(Type Val)
     {
-        if( Val == 0 )return 32;
+        if( Val == 0 )return sizeof(Type)*8;
 
-        Diligent::Uint32 MSB = 31;
-        while( !(Val & (1u << MSB)) )
+        Diligent::Uint32 MSB = sizeof(Type)*8-1;
+        while( !(Val & (Type{1} << MSB)) )
             --MSB;
 
         return MSB;
     }
 
-    static Diligent::Uint32 GetLSB(Diligent::Uint32 Val)
+    template<typename Type>
+    static Diligent::Uint32 GetLSB(Type Val)
     {
-        if( Val == 0 )return 32;
+        if( Val == 0 )return sizeof(Type)*8;
 
         Diligent::Uint32 LSB = 0;
-        while( !(Val & (1u << LSB)) )
+        while( !(Val & (Type{1} << LSB)) )
             ++LSB;
 
         return LSB;
     }
+
+    template<typename Type>
+    static Diligent::Uint32 CountOneBits(Type Val)
+    {
+        Diligent::Uint32 bits = 0;
+        while(Val != 0)
+        {
+            Val &= (Val-1);
+            ++bits;
+        }
+        return bits;
+    }
 };
diff --git a/Platforms/Linux/include/LinuxPlatformMisc.h b/Platforms/Linux/include/LinuxPlatformMisc.h
index 40cbc849..6c7e5193 100644
--- a/Platforms/Linux/include/LinuxPlatformMisc.h
+++ b/Platforms/Linux/include/LinuxPlatformMisc.h
@@ -40,4 +40,59 @@ struct LinuxMisc : public BasicPlatformMisc
 
         return MSB;
     }
+
+    static Diligent::Uint32 GetLSB(Diligent::Uint32 Val)
+    {
+        if( Val == 0 )return 32;
+
+        // Returns the number of trailing 0-bits in x, starting at the 
+        // least significant bit position. If x is 0, the result is undefined.
+        auto TrailingZeros = __builtin_ctz(Val);
+        auto LSB = TrailingZeros;
+        VERIFY_EXPR(LSB == BasicPlatformMisc::GetLSB(Val));
+
+        return LSB;
+    }
+
+    static Diligent::Uint32 GetMSB(Diligent::Uint64 Val)
+    {
+        if( Val == 0 )return 64;
+
+        // Returns the number of leading 0-bits in x, starting at the 
+        // most significant bit position. If x is 0, the result is undefined.
+        auto LeadingZeros = __builtin_clzll(Val);
+        auto MSB = 63 - LeadingZeros;
+        VERIFY_EXPR(MSB == BasicPlatformMisc::GetMSB(Val));
+
+        return MSB;
+    }
+
+    static Diligent::Uint32 GetLSB(Diligent::Uint64 Val)
+    {
+        if( Val == 0 )return 64;
+
+        // Returns the number of trailing 0-bits in x, starting at the 
+        // least significant bit position. If x is 0, the result is undefined.
+        auto TrailingZeros = __builtin_ctzll(Val);
+        auto LSB = TrailingZeros;
+        VERIFY_EXPR(LSB == BasicPlatformMisc::GetLSB(Val));
+
+        return LSB;
+    }
+
+    static Diligent::Uint32 CountOneBits(Diligent::Uint32 Val)
+    {
+        // Returns the number of 1-bits in x.
+        auto bits = __builtin_popcount(Val);
+        VERIFY_EXPR(bits == BasicPlatformMisc::CountOneBits(Val));
+        return bits;
+    }
+
+    static Diligent::Uint32 CountOneBits(Diligent::Uint64 Val)
+    {
+        // Returns the number of 1-bits in x.
+        auto bits = __builtin_popcountll(Val);
+        VERIFY_EXPR(bits == BasicPlatformMisc::CountOneBits(Val));
+        return bits;
+    }
 };
diff --git a/Platforms/Win32/include/Win32Atomics.h b/Platforms/Win32/include/Win32Atomics.h
index 5ff75899..0af2f964 100644
--- a/Platforms/Win32/include/Win32Atomics.h
+++ b/Platforms/Win32/include/Win32Atomics.h
@@ -27,18 +27,17 @@ struct WindowsAtomics
 {
     // Use windows-specific atomics. Standard atomic eventually call
     // the same functions, but introduce significant overhead
-
-    typedef long Long;
-    typedef volatile long AtomicLong;
-    typedef long long Int64;
-    typedef volatile long long AtomicInt64;
+    using Long        = long;
+    using AtomicLong  = volatile long;
+    using Int64       = long long;
+    using AtomicInt64 = volatile long long;
 
     // The function returns the resulting INCREMENTED value.
-    static Long AtomicIncrement(AtomicLong &Val);
+    static Long  AtomicIncrement(AtomicLong  &Val);
     static Int64 AtomicIncrement(AtomicInt64 &Val);
 
     // The function returns the resulting DECREMENTED value.
-    static Long AtomicDecrement(AtomicLong &Val);
+    static Long  AtomicDecrement(AtomicLong  &Val);
     static Int64 AtomicDecrement(AtomicInt64 &Val);
     
     // The function compares the Destination value with the Comparand value. If the Destination value is equal 
@@ -47,6 +46,6 @@ struct WindowsAtomics
     // The function returns the initial value of the Destination parameter
     static Long AtomicCompareExchange( AtomicLong &Destination, Long Exchange, Long Comparand);
 
-    static Long AtomicAdd( AtomicLong &Destination, Long Val);
+    static Long  AtomicAdd( AtomicLong  &Destination, Long  Val);
     static Int64 AtomicAdd( AtomicInt64 &Destination, Int64 Val);
 };
diff --git a/Platforms/Win32/include/Win32PlatformMisc.h b/Platforms/Win32/include/Win32PlatformMisc.h
index 8e354097..05b1bc52 100644
--- a/Platforms/Win32/include/Win32PlatformMisc.h
+++ b/Platforms/Win32/include/Win32PlatformMisc.h
@@ -30,7 +30,7 @@
 
 struct WindowsMisc : public BasicPlatformMisc
 {
-    static Diligent::Uint32 GetMSB(Diligent::Uint32 Val)
+    inline static Diligent::Uint32 GetMSB(Diligent::Uint32 Val)
     {
         if( Val == 0 )return 32;
 
@@ -41,7 +41,18 @@ struct WindowsMisc : public BasicPlatformMisc
         return MSB;
     }
 
-    static Diligent::Uint32 GetLSB(Diligent::Uint32 Val)
+    inline static Diligent::Uint32 GetMSB(Diligent::Uint64 Val)
+    {
+        if( Val == 0 )return 64;
+
+        unsigned long MSB = 64;
+        _BitScanReverse64(&MSB, Val);
+        VERIFY_EXPR(MSB == BasicPlatformMisc::GetMSB(Val));
+
+        return MSB;
+    }
+
+    inline static Diligent::Uint32 GetLSB(Diligent::Uint32 Val)
     {
         if( Val == 0 )return 32;
 
@@ -51,4 +62,29 @@ struct WindowsMisc : public BasicPlatformMisc
 
         return LSB;
     }
+
+    inline static Diligent::Uint32 GetLSB(Diligent::Uint64 Val)
+    {
+        if( Val == 0 )return 64;
+
+        unsigned long LSB = 64;
+        _BitScanForward64(&LSB, Val);
+        VERIFY_EXPR(LSB == BasicPlatformMisc::GetLSB(Val));
+
+        return LSB;
+    }
+
+    inline static Diligent::Uint32 CountOneBits(Diligent::Uint32 Val)
+    {
+        auto Bits = __popcnt(Val);
+        VERIFY_EXPR(Bits == BasicPlatformMisc::CountOneBits(Val));
+        return Bits;
+    }
+
+    inline static Diligent::Uint32 CountOneBits(Diligent::Uint64 Val)
+    {
+        auto Bits = __popcnt64(Val);
+        VERIFY_EXPR(Bits == BasicPlatformMisc::CountOneBits(Val));
+        return static_cast<Diligent::Uint32>(Bits);
+    }
 };
diff --git a/Platforms/interface/PlatformMisc.h b/Platforms/interface/PlatformMisc.h
index 76b0512c..4d64342a 100644
--- a/Platforms/interface/PlatformMisc.h
+++ b/Platforms/interface/PlatformMisc.h
@@ -27,19 +27,19 @@
 
 #if PLATFORM_WIN32 || PLATFORM_UNIVERSAL_WINDOWS
     #include "../Win32/include/Win32PlatformMisc.h"
-    typedef WindowsMisc PlatformMisc;
+    using PlatformMisc = WindowsMisc;
 
 #elif PLATFORM_ANDROID
     #include "../Android/include/AndroidPlatformMisc.h"
-    typedef AndroidMisc PlatformMisc;
+    using PlatformMisc = AndroidMisc;
 
 #elif PLATFORM_LINUX
     #include "../Linux/include/LinuxPlatformMisc.h"
-    typedef LinuxMisc PlatformMisc;
+    using PlatformMisc = LinuxMisc;
 
 #elif PLATFORM_MACOS || PLATFORM_IOS
     #include "../Apple/include/ApplePlatformMisc.h"
-    typedef AppleMisc PlatformMisc;
+    using PlatformMisc = AppleMisc;
 
 #else