MAINT: do not try SIMD arithmetic loops if count < 4

mattip · mattip · commit cfa2b176956b · 2022-12-28T00:09:28.000+02:00
diff --git a/numpy/core/src/umath/loops_arithm_fp.dispatch.c.src b/numpy/core/src/umath/loops_arithm_fp.dispatch.c.src
@@ -537,7 +537,7 @@ NPY_NO_EXPORT void NPY_CPU_DISPATCH_CURFX(@TYPE@_@kind@)
         *((@type@ *)iop1) = io1;
 #endif
     }
-    else if (!run_binary_simd_@kind@_@TYPE@(args, dimensions, steps)) {
+    else if (dimensions[0] < 4 || !run_binary_simd_@kind@_@TYPE@(args, dimensions, steps)) {
         BINARY_LOOP {
             const @type@ in1 = *(@type@ *)ip1;
             const @type@ in2 = *(@type@ *)ip2;

Original file line number	Diff line number	Diff line change
`@@ -537,7 +537,7 @@ NPY_NO_EXPORT void NPY_CPU_DISPATCH_CURFX(@TYPE@_@kind@)`
`537`	`537`	`((@type@ )iop1) = io1;`
`538`	`538`	`#endif`
`539`	`539`	`}`
`540`		`- else if (!run_binary_simd_@kind@_@TYPE@(args, dimensions, steps)) {`
	`540`	`+ else if (dimensions[0] < 4 \|\| !run_binary_simd_@kind@_@TYPE@(args, dimensions, steps)) {`
`541`	`541`	`BINARY_LOOP {`
`542`	`542`	`const @type@ in1 = (@type@ )ip1;`
`543`	`543`	`const @type@ in2 = (@type@ )ip2;`