From 7d5fa424153b59c69bf1188590810381c7dadc9e Mon Sep 17 00:00:00 2001
From: TristonianJones <tswadell@google.com>
Date: Fri, 27 Oct 2023 14:05:59 -0700
Subject: [PATCH] Adjust cost factor clamping

---
 checker/cost.go | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/checker/cost.go b/checker/cost.go
index 04bfa70b..3470d0a3 100644
--- a/checker/cost.go
+++ b/checker/cost.go
@@ -226,7 +226,7 @@ func addUint64NoOverflow(x, y uint64) uint64 {
 // multiplyUint64NoOverflow multiplies non-negative ints. If the result is exceeds math.MaxUint64, math.MaxUint64
 // is returned.
 func multiplyUint64NoOverflow(x, y uint64) uint64 {
-	if x > 0 && y > 0 && x > math.MaxUint64/y {
+	if y != 0 && x > math.MaxUint64/y {
 		return math.MaxUint64
 	}
 	return x * y
@@ -238,7 +238,11 @@ func multiplyByCostFactor(x uint64, y float64) uint64 {
 	if xFloat > 0 && y > 0 && xFloat > math.MaxUint64/y {
 		return math.MaxUint64
 	}
-	return uint64(math.Ceil(xFloat * y))
+	ceil := math.Ceil(xFloat * y)
+	if ceil >= doubleTwoTo64 {
+		return math.MaxUint64
+	}
+	return uint64(ceil)
 }
 
 var (
@@ -692,3 +696,7 @@ func isScalar(t *types.Type) bool {
 	}
 	return false
 }
+
+var (
+	doubleTwoTo64 = math.Ldexp(1.0, 64)
+)