On Wed, 1 Mar 2023 14:27:09 GMT, Andrey Turbanov <aturba...@openjdk.org> wrote:
>> Last and certainly not least in the port of FDLIBM to Java, the >> transcendental methods for sin, cos, and tan. >> >> Some more tests are to be written in the StrictMath directory to verify that >> the StrictMath algorihtm for sin/cos/tan is being used rather than a >> different one. However, I wanted to get the rest of the change out for >> review first. >> >> The sin/cos/tan methods are grouped together since they share the same >> argument reduction logic. Argument reduction is the process of mapping an >> argument of a function to an argument in a restricted range (and possibly >> returning some function of the reduced argument). For sin, cos, and tan, >> since they are fundamentally periodic with respect to a multiple of pi, >> argument reduction is done to find the remainder of the original argument >> with respect to pi/2. > > src/java.base/share/classes/java/lang/FdLibm.java line 814: > >> 812: >> 813: static final double >> 814: twon24 = 0x1.0p-24; // 5.96046447753906250000e-08 > > Suggestion: > > twon24 = 0x1.0p-24; // 5.96046447753906250000e-08 Would it be worthwhile to declare this as a compile time constant, similarly to `TWO24`? If it's used only here, then probably not. ------------- PR: https://git.openjdk.org/jdk/pull/12800
