Code Review for 6614100

Prepared by: Thomas Rodriguez (never) on Mon Jun 2 13:29:23 PDT 2008
Workspace:/export/ws/hs12
Compare against: /net/jano2/export2/hotspot/ws/12/baseline
Summary of changes: 58 lines changed: 0 ins; 58 del; 0 mod; 1963 unchg
Patch of changes: 6614100.patch
Author comments:
6614100: EXCEPTION_ACCESS_VIOLATION while running Eclipse with 1.6.0_05-ea
Summary:
Reviewed-by:

The fix for 6552204 attempted to undo useless Phi of AddPs but that
exposed a preexisting that could result in crashes during code
generation. PhaseChaitin::stretch_base_pointer_live_ranges stretches
the base pointers for live ranges and in some cases may have to
construct a NULL base. It constructs an Ideal NULL instead of a mach
one and if the Ideal NULL is ever used in a Phi with real machine
values we will die during register allocation. For hs12 I'm removing
the Phi of AddP code since causes the issue to disappear again. A
real fix to the derived pointer code will be done under the bug
6709742 in a later release.

This fix will be going into hs12 for 6u10 and hs13 or hs14.

Tested with eclipse, runthese jck, and nsk on i586 and amd64

Bug id: 6614100: EXCEPTION_ACCESS_VIOLATION while running Eclipse with 1.6.0_05-ea
Legend: Modified file
Deleted file
New file

Cdiffs Udiffs Sdiffs Frames Old New Patch Raw src/share/vm/opto/cfgnode.cpp

58 lines changed: 0 ins; 58 del; 0 mod; 1963 unchg

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