diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h
index c89663575e7..cedbc5bb32b 100644
--- a/src/compiler/nir/nir.h
+++ b/src/compiler/nir/nir.h
@@ -1338,6 +1338,11 @@ typedef enum {
    NIR_OP_IS_ASSOCIATIVE = (1 << 1),
 } nir_op_algebraic_property;
 
+/* vec16 is the widest ALU op in NIR, making the max number of input of ALU
+ * instructions to be the same as NIR_MAX_VEC_COMPONENTS.
+ */
+#define NIR_ALU_MAX_INPUTS NIR_MAX_VEC_COMPONENTS
+
 typedef struct {
    const char *name;
 
@@ -1372,14 +1377,14 @@ typedef struct {
    /**
     * The number of components in each input
     */
-   uint8_t input_sizes[NIR_MAX_VEC_COMPONENTS];
+   uint8_t input_sizes[NIR_ALU_MAX_INPUTS];
 
    /**
     * The type of vector that each input takes. Note that negate and
     * absolute value are only allowed on inputs with int or float type and
     * behave differently on the two.
     */
-   nir_alu_type input_types[NIR_MAX_VEC_COMPONENTS];
+   nir_alu_type input_types[NIR_ALU_MAX_INPUTS];
 
    nir_op_algebraic_property algebraic_properties;