Try not to optimize the loop

Signed-off-by: jmug <u.g.a.mariano@gmail.com>

testdata/addupto.zig

@@ -1,9 +1,14 @@
 const expect = @import("std").testing.expect;
 
-pub export fn addUpTo(to: u32) u32 {
-    var res: u32 = 0;
-    for (0..to) |_| {
-        res += to;
+pub export fn addUpTo(to: i32) i32 {
+    var res: i32 = 0;
+    for (0..@intCast(to)) |i| {
+        const ii: i32 = @intCast(i);
+        if (ii < 20) {
+            res += ii * to;
+        } else {
+            res += ii + to * 2;
+        }
     }
     return res;
 }