New PR fixes issue with shared RawAddress instances in AArch4 address lowering

[Andrew Dinn]

The problems I had seen with reading of binary files in netbeans
recurred once the AArch64 address lowering patch went live. I tracked it
down to a problem with RawAddress instances being shared between reads
with different loaded data types (more details in the PR).

The fix is a fairly simple tweak to ensure that addresses are lowered
one at a time. n.b. if lowering of a shared RawAddress from two
different uses does actually result in the same displacement mode
AArch64Address (because the loaded data types are the same) then the
unique add in the lower method should ensure only a single
AArch64Address appears in the graph.

I submitted the following PR

https://github.com/graalvm/graal/pull/224

which has passed checks and is sitting ready to be pulled. Could someone
please review it?

regards,


Andrew Dinn
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Senior Principal Software Engineer
Red Hat UK Ltd
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