Revert "ggml-cuda : add ar_add() to avoid ambiguous operator+ for half/bfloat16 in...

This reverts commit 5cd228494af3973294e90aad95b58c2ede400f43.

Reverting in favor of:
https://github.com/ggml-org/llama.cpp/pull/22994

diff --git a/ggml/src/ggml-cuda/allreduce.cu b/ggml/src/ggml-cuda/allreduce.cu
index 03d88968cd5ca7ea17019f75eda4b73deec5e545..434689abd9523f4291818f17097df1d9df236b1e 100644 (file)
--- a/ggml/src/ggml-cuda/allreduce.cu
+++ b/ggml/src/ggml-cuda/allreduce.cu
@@ -105,20 +105,6 @@ static constexpr int GGML_CUDA_AR_KERNEL_BLOCKS = 8;
 // blocks.  Tail elements (the leftover < ELEMS_PER_VEC at the end) are
 // handled only by block 0 to avoid cross-block writes to the same slots.
 // ---------------------------------------------------------------------------
-
-// CUDA 11.8 does not expose operator+ for half/bfloat16 below sm_530,
-// so use the explicit intrinsics to avoid ambiguous implicit conversions.
-template<typename T>
-static __device__ inline T ar_add(T a, T b) {
-    if constexpr (std::is_same_v<T, half>) {
-        return __hadd(a, b);
-    } else if constexpr (std::is_same_v<T, nv_bfloat16>) {
-        return __float2bfloat16(__bfloat162float(a) + __bfloat162float(b));
-    } else {
-        return a + b;
-    }
-}
-
 template <typename T_dst, typename T_wire>
 static __global__ void ggml_cuda_ar_kernel(
         const T_dst  *              sendbuf,
@@ -198,13 +184,13 @@ static __global__ void ggml_cuda_ar_kernel(
             #pragma unroll
             for (int k = 0; k < ELEMS_PER_VEC; ++k) {
                 const T_wire d_low = ggml_cuda_cast<T_wire>(sendbuf[off + k]);
-                recvbuf[off + k] = ar_add(ggml_cuda_cast<T_dst>(d_low), ggml_cuda_cast<T_dst>(wire[k]));
+                recvbuf[off + k] = ggml_cuda_cast<T_dst>(d_low) + ggml_cuda_cast<T_dst>(wire[k]);
             }
         }
         if (bid == 0 && tid < count - tail) {
             const T_wire d_low = ggml_cuda_cast<T_wire>(sendbuf[tail + tid]);
             recvbuf[tail + tid] =
-                ar_add(ggml_cuda_cast<T_dst>(d_low), ggml_cuda_cast<T_dst>(host_other[tail + tid]));
+                ggml_cuda_cast<T_dst>(d_low) + ggml_cuda_cast<T_dst>(host_other[tail + tid]);
         }
     }
 }
@@ -224,7 +210,7 @@ static __global__ void ggml_cuda_ar_add_kernel(
     const int nt  = gridDim.x * blockDim.x;
     for (int i = tid; i < count; i += nt) {
         const T_src d_low = ggml_cuda_cast<T_src>(dst[i]);
-        dst[i] = ar_add(ggml_cuda_cast<T_dst>(d_low), ggml_cuda_cast<T_dst>(src[i]));
+        dst[i] = ggml_cuda_cast<T_dst>(d_low) + ggml_cuda_cast<T_dst>(src[i]);
     }
 }