From fd912b348ccde6cce3a56d4cc748b10d05ff3edd Mon Sep 17 00:00:00 2001
From: chenyu <chenyu@fastmail.com>
Date: Wed, 29 Jul 2026 18:45:23 -0400
Subject: [PATCH] generic c0*x<c1 [pr] (#17291)

---
 test/null/test_uop_symbolic.py | 2 ++
 tinygrad/uop/symbolic.py       | 7 ++-----
 2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/test/null/test_uop_symbolic.py b/test/null/test_uop_symbolic.py
index d921a5cb17..9334440753 100644
--- a/test/null/test_uop_symbolic.py
+++ b/test/null/test_uop_symbolic.py
@@ -347,6 +347,8 @@ class TestSymbolic(unittest.TestCase):
   def test_mul_lt(self):
     self.helper_test_variable(Variable("a", 0, 5)*4 < 13, 0, 1, "(a<4)")
     self.helper_test_variable(Variable("a", 0, 5)*4 < 16, 0, 1, "(a<4)")
+    self.helper_test_variable(Variable("a", -5, 5)*4 < -13, 0, 1, "(a<-3)")
+    self.helper_test_variable(Variable("a", -5, 5)*-4 < 13, 0, 1, "((a*-1)<4)")
     c0, c1 = 2, 2**54+1
     self.helper_test_variable(Variable("a", 0, c1)*c0 < c1, 0, 1, f"(a<{2**53+1})")
     c0, c1 = -2, -(2**54-1)
diff --git a/tinygrad/uop/symbolic.py b/tinygrad/uop/symbolic.py
index 67b196bd55..65da3f2f56 100644
--- a/tinygrad/uop/symbolic.py
+++ b/tinygrad/uop/symbolic.py
@@ -262,12 +262,9 @@ symbolic = symbolic_simple+commutative+PatternMatcher([
   # (x//c1)//c2 -> x//(c1*c2) for c2>0
   ((UPat.var("x") // UPat.cvar("c1")) // UPat.cvar("c2"), lambda x,c1,c2: x//(c1*c2) if c2.vmin>0 else None),
   # ** lt **
-  # c0*x<c1 for positive int c0,c1
+  # c0*x<c1 -> sign(c0)*x < ceil(c1/abs(c0))
   ((UPat.cvar("c0")*UPat.var("x", dtype=dtypes.weakint))<UPat.cvar("c1"),
-   lambda x,c0,c1: x<(-(-c1.arg//c0.arg)) if c0.arg > 0 and c1.arg > 0 else None),
-  # c0*x<c1 for negative int c0 and non-positive c1
-  ((UPat.cvar("c0")*UPat.var("x", dtype=dtypes.weakint))<UPat.cvar("c1"),
-   lambda x,c0,c1: (-x)<-((-c1.arg)//(-c0.arg)) if c0.arg < 0 and c0.arg != -1 and c1.arg <= 0 else None),
+   lambda x,c0,c1: (x if c0.arg > 0 else -x)<-(-c1.arg//abs(c0.arg)) if abs(c0.arg) > 1 else None),
   # x//d<c -> x<c*d for d>0, and -> c*d<x for d<0
   ((UPat.var("x", dtype=dtypes.weakint)//UPat.cvar("d"))<UPat.cvar("c"),
    lambda x,d,c: (x<c.arg*d.arg) if d.arg > 0 else (x>c.arg*d.arg) if d.arg < 0 else None),