Request for reviews (XS): 6829127: Deoptimization Failure on Specjvm98 _227_mtrt with -XX:+DeoptimizeALot since Hs11 b01

[changpeng fang - Sun Microsystems - Santa Clara United States]

http://cr.openjdk.java.net/~cfang/6829127/webrev.00/

Fixed 6829127: Deoptimization Failure on Specjvm98 _227_mtrt with 
-XX:+DeoptimizeALot since Hs11 b01

Problem:
The safepoint blob  can be used in methods which are using the non 
standard control word for optimized
float math. However, the non standard control word may leak out to other 
codes which will cause assertion
failure in RegisterSaver::save_live_registers.

Solution:
We can deopt at a poll point with the non standard control word, so we 
make the deopt blob to not complain about
the non standard word and set the standard control word after 
restore_result_registers in the deopt blob.

Tests: specjvm98, specjvm2008 with -XX:+DeoptimizeALot


Thanks,

Changpeng