code review 5484076: pkg/math: undo manual inlining of IsInf and IsNaN

src/pkg/math/tan.go

Index: src/pkg/math/tan.go
===================================================================
--- a/src/pkg/math/tan.go
+++ b/src/pkg/math/tan.go
@@ -88,13 +88,11 @@
 		PI4C = 2.69515142907905952645E-15                            // 0x3ce8469898cc5170,
 		M4PI = 1.273239544735162542821171882678754627704620361328125 // 4/pi
 	)
-	// TODO(rsc): Remove manual inlining of IsNaN, IsInf
-	// when compiler does it for us
 	// special cases
 	switch {
-	case x == 0 || x != x: // x == 0 || IsNaN():
+	case x == 0 || IsNaN(x):
 		return x // return ±0 || NaN()
-	case x < -MaxFloat64 || x > MaxFloat64: // IsInf(x, 0):
+	case IsInf(x, 0):
 		return NaN()
 	}