saturate_cast via asm cvt command

modules/gpu/include/opencv2/gpu/device/saturate_cast.hpp

@@ -58,35 +58,47 @@ namespace cv { namespace gpu { namespace device
 
     template<> __device__ __forceinline__ uchar saturate_cast<uchar>(schar v)
     {
-        return (uchar) ::max((int)v, 0);
+        uint res = 0;
+        int vi = v;
+        asm("cvt.sat.u8.s8 %0, %1;" : "=r"(res) : "r"(vi));
+        return res;
+    }
+    template<> __device__ __forceinline__ uchar saturate_cast<uchar>(short v)
+    {
+        uint res = 0;
+        asm("cvt.sat.u8.s16 %0, %1;" : "=r"(res) : "h"(v));
+        return res;
     }
     template<> __device__ __forceinline__ uchar saturate_cast<uchar>(ushort v)
     {
-        return (uchar) ::min((uint)v, (uint)UCHAR_MAX);
+        uint res = 0;
+        asm("cvt.sat.u8.u16 %0, %1;" : "=r"(res) : "h"(v));
+        return res;
     }
     template<> __device__ __forceinline__ uchar saturate_cast<uchar>(int v)
     {
-        return (uchar)((uint)v <= UCHAR_MAX ? v : v > 0 ? UCHAR_MAX : 0);
+        uint res = 0;
+        asm("cvt.sat.u8.s32 %0, %1;" : "=r"(res) : "r"(v));
+        return res;
     }
     template<> __device__ __forceinline__ uchar saturate_cast<uchar>(uint v)
     {
-        return (uchar) ::min(v, (uint)UCHAR_MAX);
+        uint res = 0;
+        asm("cvt.sat.u8.u32 %0, %1;" : "=r"(res) : "r"(v));
+        return res;
     }
-    template<> __device__ __forceinline__ uchar saturate_cast<uchar>(short v)
-    {
-        return saturate_cast<uchar>((uint)v);
-    }
-
     template<> __device__ __forceinline__ uchar saturate_cast<uchar>(float v)
     {
-        int iv = __float2int_rn(v);
-        return saturate_cast<uchar>(iv);
+        uint res = 0;
+        asm("cvt.rni.sat.u8.f32 %0, %1;" : "=r"(res) : "f"(v));
+        return res;
     }
     template<> __device__ __forceinline__ uchar saturate_cast<uchar>(double v)
     {
-    #if defined __CUDA_ARCH__ && __CUDA_ARCH__ >= 130
-        int iv = __double2int_rn(v);
-        return saturate_cast<uchar>(iv);
+    #if __CUDA_ARCH__ >= 130
+        uint res = 0;
+        asm("cvt.rni.sat.u8.f64 %0, %1;" : "=r"(res) : "d"(v));
+        return res;
     #else
         return saturate_cast<uchar>((float)v);
     #endif
@@ -94,35 +106,47 @@ namespace cv { namespace gpu { namespace device
 
     template<> __device__ __forceinline__ schar saturate_cast<schar>(uchar v)
     {
-        return (schar) ::min((int)v, SCHAR_MAX);
+        uint res = 0;
+        uint vi = v;
+        asm("cvt.sat.s8.u8 %0, %1;" : "=r"(res) : "r"(vi));
+        return res;
     }
-    template<> __device__ __forceinline__ schar saturate_cast<schar>(ushort v)
+    template<> __device__ __forceinline__ schar saturate_cast<schar>(short v)
     {
-        return (schar) ::min((uint)v, (uint)SCHAR_MAX);
+        uint res = 0;
+        asm("cvt.sat.s8.s16 %0, %1;" : "=r"(res) : "h"(v));
+        return res;
     }
-    template<> __device__ __forceinline__ schar saturate_cast<schar>(int v)
+    template<> __device__ __forceinline__ schar saturate_cast<schar>(ushort v)
     {
-        return (schar)((uint)(v-SCHAR_MIN) <= (uint)UCHAR_MAX ? v : v > 0 ? SCHAR_MAX : SCHAR_MIN);
+        uint res = 0;
+        asm("cvt.sat.s8.u16 %0, %1;" : "=r"(res) : "h"(v));
+        return res;
     }
-    template<> __device__ __forceinline__ schar saturate_cast<schar>(short v)
+    template<> __device__ __forceinline__ schar saturate_cast<schar>(int v)
     {
-        return saturate_cast<schar>((int)v);
+        uint res = 0;
+        asm("cvt.sat.s8.s32 %0, %1;" : "=r"(res) : "r"(v));
+        return res;
     }
     template<> __device__ __forceinline__ schar saturate_cast<schar>(uint v)
     {
-        return (schar) ::min(v, (uint)SCHAR_MAX);
+        uint res = 0;
+        asm("cvt.sat.s8.u32 %0, %1;" : "=r"(res) : "r"(v));
+        return res;
     }
-
     template<> __device__ __forceinline__ schar saturate_cast<schar>(float v)
     {
-        int iv = __float2int_rn(v);
-        return saturate_cast<schar>(iv);
+        uint res = 0;
+        asm("cvt.rni.sat.s8.f32 %0, %1;" : "=r"(res) : "f"(v));
+        return res;
     }
     template<> __device__ __forceinline__ schar saturate_cast<schar>(double v)
     {
-    #if defined __CUDA_ARCH__ && __CUDA_ARCH__ >= 130
-        int iv = __double2int_rn(v);
-        return saturate_cast<schar>(iv);
+    #if __CUDA_ARCH__ >= 130
+        uint res = 0;
+        asm("cvt.rni.sat.s8.f64 %0, %1;" : "=r"(res) : "d"(v));
+        return res;
     #else
         return saturate_cast<schar>((float)v);
     #endif
@@ -130,30 +154,41 @@ namespace cv { namespace gpu { namespace device
 
     template<> __device__ __forceinline__ ushort saturate_cast<ushort>(schar v)
     {
-        return (ushort) ::max((int)v, 0);
+        ushort res = 0;
+        int vi = v;
+        asm("cvt.sat.u16.s8 %0, %1;" : "=h"(res) : "r"(vi));
+        return res;
     }
     template<> __device__ __forceinline__ ushort saturate_cast<ushort>(short v)
     {
-        return (ushort) ::max((int)v, 0);
+        ushort res = 0;
+        asm("cvt.sat.u16.s16 %0, %1;" : "=h"(res) : "h"(v));
+        return res;
     }
     template<> __device__ __forceinline__ ushort saturate_cast<ushort>(int v)
     {
-        return (ushort)((uint)v <= (uint)USHRT_MAX ? v : v > 0 ? USHRT_MAX : 0);
+        ushort res = 0;
+        asm("cvt.sat.u16.s32 %0, %1;" : "=h"(res) : "r"(v));
+        return res;
     }
     template<> __device__ __forceinline__ ushort saturate_cast<ushort>(uint v)
     {
-        return (ushort) ::min(v, (uint)USHRT_MAX);
+        ushort res = 0;
+        asm("cvt.sat.u16.u32 %0, %1;" : "=h"(res) : "r"(v));
+        return res;
     }
     template<> __device__ __forceinline__ ushort saturate_cast<ushort>(float v)
     {
-        int iv = __float2int_rn(v);
-        return saturate_cast<ushort>(iv);
+        ushort res = 0;
+        asm("cvt.rni.sat.u16.f32 %0, %1;" : "=h"(res) : "f"(v));
+        return res;
     }
     template<> __device__ __forceinline__ ushort saturate_cast<ushort>(double v)
     {
-    #if defined __CUDA_ARCH__ && __CUDA_ARCH__ >= 130
-        int iv = __double2int_rn(v);
-        return saturate_cast<ushort>(iv);
+    #if __CUDA_ARCH__ >= 130
+        ushort res = 0;
+        asm("cvt.rni.sat.u16.f64 %0, %1;" : "=h"(res) : "d"(v));
+        return res;
     #else
         return saturate_cast<ushort>((float)v);
     #endif
@@ -161,31 +196,45 @@ namespace cv { namespace gpu { namespace device
 
     template<> __device__ __forceinline__ short saturate_cast<short>(ushort v)
     {
-        return (short) ::min((int)v, SHRT_MAX);
+        short res = 0;
+        asm("cvt.sat.s16.u16 %0, %1;" : "=h"(res) : "h"(v));
+        return res;
     }
     template<> __device__ __forceinline__ short saturate_cast<short>(int v)
     {
-        return (short)((uint)(v - SHRT_MIN) <= (uint)USHRT_MAX ? v : v > 0 ? SHRT_MAX : SHRT_MIN);
+        short res = 0;
+        asm("cvt.sat.s16.s32 %0, %1;" : "=h"(res) : "r"(v));
+        return res;
     }
     template<> __device__ __forceinline__ short saturate_cast<short>(uint v)
     {
-        return (short) ::min(v, (uint)SHRT_MAX);
+        short res = 0;
+        asm("cvt.sat.s16.u32 %0, %1;" : "=h"(res) : "r"(v));
+        return res;
     }
     template<> __device__ __forceinline__ short saturate_cast<short>(float v)
     {
-        int iv = __float2int_rn(v);
-        return saturate_cast<short>(iv);
+        short res = 0;
+        asm("cvt.rni.sat.s16.f32 %0, %1;" : "=h"(res) : "f"(v));
+        return res;
     }
     template<> __device__ __forceinline__ short saturate_cast<short>(double v)
     {
-    #if defined __CUDA_ARCH__ && __CUDA_ARCH__ >= 130
-        int iv = __double2int_rn(v);
-        return saturate_cast<short>(iv);
+    #if __CUDA_ARCH__ >= 130
+        short res = 0;
+        asm("cvt.rni.sat.s16.f64 %0, %1;" : "=h"(res) : "d"(v));
+        return res;
     #else
         return saturate_cast<short>((float)v);
     #endif
     }
 
+    template<> __device__ __forceinline__ int saturate_cast<int>(uint v)
+    {
+        int res = 0;
+        asm("cvt.sat.s32.u32 %0, %1;" : "=r"(res) : "r"(v));
+        return res;
+    }
     template<> __device__ __forceinline__ int saturate_cast<int>(float v)
     {
         return __float2int_rn(v);
@@ -199,6 +248,25 @@ namespace cv { namespace gpu { namespace device
     #endif
     }
 
+    template<> __device__ __forceinline__ uint saturate_cast<uint>(schar v)
+    {
+        uint res = 0;
+        int vi = v;
+        asm("cvt.sat.u32.s8 %0, %1;" : "=r"(res) : "r"(vi));
+        return res;
+    }
+    template<> __device__ __forceinline__ uint saturate_cast<uint>(short v)
+    {
+        uint res = 0;
+        asm("cvt.sat.u32.s16 %0, %1;" : "=r"(res) : "h"(v));
+        return res;
+    }
+    template<> __device__ __forceinline__ uint saturate_cast<uint>(int v)
+    {
+        uint res = 0;
+        asm("cvt.sat.u32.s32 %0, %1;" : "=r"(res) : "r"(v));
+        return res;
+    }
     template<> __device__ __forceinline__ uint saturate_cast<uint>(float v)
     {
         return __float2uint_rn(v);