Add rule and test (#10189)

Co-authored-by: chenyu <chenyu@fastmail.com>

test/unit/test_uop_symbolic.py

@@ -560,6 +560,11 @@ class TestSymbolic(unittest.TestCase):
     w = cond.logical_not().where(a, b)
     self.helper_test_variable(w, 0, 3, "(b if (x<2) else a)")
 
+  def test_neg_in_comp(self):
+    a = Variable("a", 0, 3)
+    b = Variable("b", 0, 3)
+    self.helper_test_variable(-a<-b, False, True, "(b<a)")
+
   def test_where_cast(self):
     s = Variable("s", 0, 3)
     cond = s < 2

tinygrad/codegen/symbolic.py

@@ -275,6 +275,7 @@ symbolic = symbolic_simple+commutative+PatternMatcher([
   ((UPat() + (UPat()//UPat.cvar("d", vec=False))*UPat.cvar("c")).named("divs"), lambda divs,d,c: fold_unrolled_divs(divs, d.arg, c.arg)),
   # generic lt folding
   (UPat.var("x", dtypes.sints)<UPat.cvar("c", vec=False), lambda x,c: lt_folding(x, c.arg) if 0 < c.arg else None),
+  (UPat.var("x", dtypes.sints)*-1 < UPat.var("y", dtypes.sints)*-1, lambda x,y: y<x),
   # canonicalize a simplex with positive coefficients > 0
   # not x < 1 -> X > 0
   ((UPat.var("x", dtypes.ints)<1).ne(True), lambda x: (newx<1).ne(True) if (newx:=canonicalize_simplex(x)) is not None else None),