Compiler control

Controlling Java Virtual Machine (JVM) compilers might seem like an unnecessary task, but for many developers, this is an important aspect of testing. This is accomplished with method-dependent compiler flags.

In this section, we will start with a look at JVM compilation modes and then look at the compiler that can be controlled using the Java platform.

Compilation modes

The changes in the modern Java platform include granular control of both the C1 and C2 JVM compilers. As you can see in the following illustration, the Java HotSpot JVM has two JIT compilation modes C1 and C2:

Java hotSpot JVM compilation modes

The C1 and C2 compilation modes use different compilation techniques and, if used on the same code...