Optimize divisor search limit in get_greatest_divisor_below_bound

younessdkhissi · web-flow · commit 969c99f3ff07 · 2025-09-26T09:57:11.000+02:00
diff --git a/torchvision/csrc/ops/cuda/deform_conv2d_kernel.cu b/torchvision/csrc/ops/cuda/deform_conv2d_kernel.cu
@@ -305,7 +305,8 @@ void deformable_im2col(
 }
 
 int get_greatest_divisor_below_bound(int n, int bound) {
-  for (int k = bound; k > 1; --k) {
+  int limit = std::min(n/2, bound);
+  for (int k = limit; k > 1; --k) {
     if (n % k == 0) {
       return k;
     }

Original file line number	Diff line number	Diff line change
`@@ -305,7 +305,8 @@ void deformable_im2col(`
`305`	`305`	`}`
`306`	`306`
`307`	`307`	`int get_greatest_divisor_below_bound(int n, int bound) {`
`308`		`- for (int k = bound; k > 1; --k) {`
	`308`	`+ int limit = std::min(n/2, bound);`
	`309`	`+ for (int k = limit; k > 1; --k) {`
`309`	`310`	`if (n % k == 0) {`
`310`	`311`	`return k;`
`311`	`312`	`}`