Make the implementation of Log/Log2/Ln/Log1p in XLA accurate on all p…

…latforms, and tighten test tolerances accordingly. Add tests for +/-0, +/-inf, and NaN.

PiperOrigin-RevId: 504022808

tests/lax_numpy_test.py

@@ -5090,8 +5090,9 @@ def testOpGrad(self, op, rng_factory, shapes, dtype, order, tol):
       )
       for rec in GRAD_SPECIAL_VALUE_TEST_RECORDS))
   def testOpGradSpecialValue(self, op, special_value, order):
-    check_grads(op, (special_value,), order, ["fwd", "rev"],
-                atol={np.float32: 3e-3})
+    check_grads(
+        op, (special_value,), order, ['fwd', 'rev'], atol={np.float32: 4e-3}
+    )
 
   def testSincAtZero(self):
     # Some manual tests for sinc at zero, since it doesn't have well-behaved