[PATCH] D55241: AMDGPU: Should always start from the first register in VGPR indexing.

[Changpeng Fang via Phabricator via llvm-commits]

cfang added a comment.

In D55241#1317630 <https://reviews.llvm.org/D55241#1317630>, @arsenm wrote:

> We should try to use some known bits information to keep this. I have a patch to add a machine version, but there might be a better way


Would you please explain how would your knownbit approach resolve the negative index issue while keep the optimization for gfx9+?
Or just post your patch. Thanks.


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https://reviews.llvm.org/D55241