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ARM: When re-creating a branch via InsertBranch, preserve CPSR flags.
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Authored by pcc on Apr 21 2015, 9:44 PM.

Details

Summary

In particular, this preserves the kill flag, which allows the Thumb2 cbn?z
optimization to be applied in cases where a branch has been re-created after
the live variables analysis pass, e.g. by the machine block placement pass.

This appears to be low risk; a number of other targets seem to already be
doing something similar, e.g. AArch64, PowerPC.

Diff Detail

Repository
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Event Timeline

pcc updated this revision to Diff 24195.Apr 21 2015, 9:44 PM
pcc retitled this revision from to ARM: When re-creating a branch via InsertBranch, preserve CPSR flags..
pcc updated this object.
pcc edited the test plan for this revision. (Show Details)
pcc added a reviewer: t.p.northover.
pcc added a subscriber: Unknown Object (MLST).
rengolin accepted this revision.Apr 23 2015, 2:17 AM
rengolin added a reviewer: rengolin.

LGTM, Thanks!

This revision is now accepted and ready to land.Apr 23 2015, 2:17 AM
This revision was automatically updated to reflect the committed changes.