diff --git a/src/compiler/nir/nir_opt_sink.c b/src/compiler/nir/nir_opt_sink.c
index bc028226b4f..4205b04e790 100644
--- a/src/compiler/nir/nir_opt_sink.c
+++ b/src/compiler/nir/nir_opt_sink.c
@@ -76,21 +76,25 @@ can_sink_instr(nir_instr *instr, nir_move_options options, bool *can_mov_out_of_
          return options & nir_move_comparisons;
 
       /* Assuming that constants do not contribute to register pressure, it is
-       * beneficial to sink ALU instructions where all but one source is
-       * constant. Detect that case last.
+       * beneficial to sink ALU instructions where all non constant sources
+       * are the same.
        */
       if (!(options & nir_move_alu))
          return false;
 
       unsigned inputs = nir_op_infos[alu->op].num_inputs;
-      unsigned constant_inputs = 0;
+      int non_const = -1;
 
       for (unsigned i = 0; i < inputs; ++i) {
          if (is_constant_like(&alu->src[i].src))
-            constant_inputs++;
+            continue;
+         else if (non_const < 0)
+            non_const = i;
+         else if (!nir_alu_srcs_equal(alu, alu, non_const, i))
+            return false;
       }
 
-      return (constant_inputs + 1 >= inputs);
+      return true;
    }
    case nir_instr_type_intrinsic: {
       nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);