These expressions are tricky because they rely on invokedynamic, which
normally implies runtime code generation. However, since lambdas
don't actually use the "dynamicness" of invokedynamic, we can convert
them into static calls to synthetic classes at compile time.
Since I had already written code to synthesize such classes in Java
and I didn't want to rewrite it in C++, I needed to add support for
running Java code to the bootimage generator. And since the primary
VM used by the generator is purpose-built to generate AOT-compiled
code for a specific target architecture and is not capable of
generating or running JIT-compiled code for the host architecture, I
added support for loading a second, independent, host-specific VM for
running Java code.
The rest of the patch handles the fact that each method compilation
might cause new, synthetic classes to be created, so we need to make
sure those classes and their methods are included in the final heap
and code images. This required breaking some giant code blocks out of
makeCodeImage into their own methods, which makes the diff look
scarier than it really is.
The two big pieces here are basic invokedynamic support and a working
version of LambdaMetaFactory.metafactory. The latter works by
dynamically building a synthetic class with three methods: a static
factory method, a constructor for the factory method to call, and a
method to satisfy the requested interface which defers to the
specified MethodHandle.
This work relies heavily on Avian's specific MethodType and
MethodHandle implementations, which provide extra, non-standard
features to make code generation easier. That means we'll probably
need to use Avian's versions of java.lang.invoke.* even when building
with the OpenJDK or Android class libraries.
This is a bunch of commits squashed into one per Josh's request.
add dynamicTable field
add invokedynamic instruction
add defaultDynamic bootimage field
add dummy invokedynamic support in bootimage-generator
add defaultDynamic thunk
check dynamicTable offset
comment defaultDynamicThunk to fix unused function
comment defaultDynamicThunk to fix unused function
add dynamicTable / dynamicIndex stuff
comment dynamicIndex and dynamicTable
add invokedynamic instruction impl
stub out addDynamic
unstub addDynamic
don't allow tail calls in invokedynamic
implement stub JVM_GetTemporaryDirectory method
(build broken) begin add InvokeDynamicTest
Revert "(build broken) begin add InvokeDynamicTest"
This reverts commit 77f9c54e32ac66d0803eeab93e4a10d3541987a8.
add InternalError
add URLClassPath.c for openjdk-src builds
implement stub JVM_KnownToNotExist and JVM_GetResourceLookupCache methods
intercept open0 / open for openjdk
add basic java/lang/invoke stubs
remove non-public java/lang/invoke classes
fix invokedynamic example building
<wip debugging>