[PATCH] D79785: [ARM] Register pressure with -mthumb forces register reload before each call

[Oliver Stannard (Linaro) via Phabricator via llvm-commits]

ostannard added a comment.

I'd expect to see some extra checks to decide if reverting the indirect-call optimisation is profitable or not. If the loaded address is used more than three times, without being spilled, then I think it's better to leave the calls as indirect ones. If you don't think this is ever likely to be worthwhile for thumb 1, then it would be better to modify ARMTargetLowering::LowerCall to not do the transformation in the first place.



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Comment at: llvm/test/CodeGen/ARM/minsize-call-cse-2.ll:8
+; CHECK: bl g
+; CHECK: blx r
+; CHECK: bl g
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Why is one of the calls being left as an indirect branch?


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https://reviews.llvm.org/D79785