From c2f3f7a20e523bd6372150e70f4074d7bbcd1bc0 Mon Sep 17 00:00:00 2001
From: Aadeshveer Singh <24b0926@iitb.ac.in>
Date: Tue, 16 Dec 2025 17:00:18 +0530
Subject: [PATCH] ggml : use WARP_SIZE/2 for argmax reduction offset

---
 ggml/src/ggml-cuda/argmax.cu | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/ggml/src/ggml-cuda/argmax.cu b/ggml/src/ggml-cuda/argmax.cu
index 5340eedc08..51967c667c 100644
--- a/ggml/src/ggml-cuda/argmax.cu
+++ b/ggml/src/ggml-cuda/argmax.cu
@@ -21,7 +21,7 @@ static __global__ void argmax_f32(const float * __restrict__ x, int32_t * __rest
     }
 
 #pragma unroll
-    for (int offset = 16; offset > 0; offset >>= 1) {
+    for (int offset = WARP_SIZE/2; offset > 0; offset >>= 1) {
         const float val = __shfl_xor_sync(0xFFFFFFFF, maxval, offset, WARP_SIZE);
         const int   col = __shfl_xor_sync(0xFFFFFFFF, argmax, offset, WARP_SIZE);
         if (val > maxval) {
@@ -50,7 +50,7 @@ static __global__ void argmax_f32(const float * __restrict__ x, int32_t * __rest
                 argmax = shared_argmax[lane_id];
             }
 #pragma unroll
-            for (int offset = 16; offset > 0; offset >>= 1) {
+            for (int offset = WARP_SIZE/2; offset > 0; offset >>= 1) {
                 const float val = __shfl_xor_sync(0xFFFFFFFF, maxval, offset, WARP_SIZE);
                 const int   col = __shfl_xor_sync(0xFFFFFFFF, argmax, offset, WARP_SIZE);
                 if (val > maxval) {