Request for reviews (XS): 6843752: missing code for an anti-dependent Phi in GCM
Vladimir.Kozlov at Sun.COM
Fri May 22 19:45:30 PDT 2009
Fixed 6843752: missing code for an anti-dependent Phi in GCM
Changes for 6470497 (part G) incorrectly removed the code
for anti-dependent PHI pinned below load's 'early' block.
As result the load placed below this phi into the block with
lowest frequency and a wrong value is loaded.
In the test case the load placed inside loop which modifies
the loaded value to NULL. As result we got NULL exception.
Don't place a load below anti-dependent PHI.
Added the regression test modified to show the problem
in latest VM (the loop body executed less time then
the code before the loop).
Fix verified (y/n): y, bug's test
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