RFR: 8318982: improve Exceptions::special_exception

[Doug Simon]

On Fri, 27 Oct 2023 14:03:45 GMT, Doug Simon <dnsimon at openjdk.org> wrote:

> This PR consolidates the 2 almost identical versions of `Exceptions::special_exception` into a single method.
> If a special exception is thrown and `-Xlog:exceptions` is enabled, a log message is emitted and it indicates the special handling.
> 
> Here's an example in the output from running `compiler/linkage/LinkageErrors.java` with `-Xlog:exceptions -Xcomp`:
> 
> [0.194s][info][exceptions] Exception <java/lang/IllegalAccessError: class java.lang.module.ModuleDescriptor$1 tried to access private method 'void java.lang.module.ModuleDescriptor$Exports.<init>(java.util.Set, java.lang.String, java.util.Set, boolean)' (java.lang.module.ModuleDescriptor$1 and java.lang.module.ModuleDescriptor$Exports are in module java.base of loader 'bootstrap')> (0x0000000000000000)
> thrown [src/hotspot/share/interpreter/linkResolver.cpp, line 591]
> for thread 0x000000011e18c600
> thread cannot call Java, throwing pre-allocated exception: a 'java/lang/VirtualMachineError'{0x0000000772e06f00}
> 
> 
> The motivation for this change was work on [JDK-8318694](https://bugs.openjdk.org/browse/JDK-8318694) where it's useful to know when exceptions are thrown on a CompilerThread.

src/hotspot/share/utilities/exceptions.cpp line 111:

> 109: #endif // ASSERT
> 110: 
> 111:   if (!thread->can_call_java()) {

If this method was called from `Exceptions::_throw`, a log message will have already been emitted. I think the duplication is acceptable for these special exceptions.

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PR Review Comment: https://git.openjdk.org/jdk/pull/16401#discussion_r1374651692