Hello everyone!

Short version:
I'm wondering if someone could clear up for me whether a Dalvik port
to ThumbEE would be of any benefit, especially when it comes to
startup application performance, before the JIT kicks in.

Longer version:
I am writing to get more informed opinions about ThumbEE / Jazelle RCT
port of Dalvik.  Any thoughts?  I got the idea from reading the
"Dalvik Porting" guide [1] and the ARM Cortex A8 documentation [2],
[3].  The documented instructions do some seemingly useful things [4]:

New features provided by ThumbEE include automatic null pointer checks
on every load and store instruction, an instruction to perform an
array bounds check, access to registers r8-r15 (where the Jazelle/DBX
Java VM state is held), and special instructions that call a handler.
[39] Handlers are small sections of frequently called code, commonly
used to implement a feature of a high level language, such as
allocating memory for a new object. These changes come from
repurposing a handful of opcodes, and knowing the core is in the new
ThumbEE mode.

Apparently, using/licensing Jazelle from ARM used to be a PITA, but I
get the impression ARM has learned from its mistakes and now the next-
gen Jazelle, Jazelle RCT / ThumbEE, is documented [2] and can be used
without licensing.

I get the impression that the Snapdragon / ARM chips in the Morotola
DROID and Nexus One have Jazelle RCT support, so they could really
benefit from ThumbEE instructions.

Thoughts, comments, feedback, rebuttals, etc. would all be greatly

Thank you!


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