RFR(M): 8024069: replace_in_map() should operate on parent maps
roland.westrelin at oracle.com
Sat Oct 12 14:31:31 PDT 2013
The improved type coming from a type check when it is done inside an inlined method may be lost once compilation exits from the inlinee because GraphKit::replace_in_map() doesn't update the maps of caller methods.
When updating the parent maps, the replacement must be safe. This is done 1) by following the control edges to check that the control of the inlinee's map post dominate the control of the parent's maps 2) not doing any update in parent maps if the replace_in_map is called inside a PreserveJVMState block because PreserveJVMState doesn't do a deep copy of the caller states. The update itself must be done in the exits maps of the Parsers of the caller. I've added code to chain them together so that replace_in_map can iterate over the Parsers of callers.
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