Backport bf8101e4fd1a532aed4c6b6a33d202e143ce303f to 19.x

[topperc]

The InitUndef pass is incorrectly sharing state between different runs of the pass.

Discussion here #107079 (comment) suggests someone hitting a functional issue from this on 19.1.0.

CC @joe-img @preames @BeMg @lukel97 @nikic

[llvmbot]

@llvm/issue-subscribers-backend-risc-v

Author: Craig Topper (topperc)

The InitUndef pass is incorrectly sharing state between different runs of the pass.

Discussion here #107079 (comment) suggests someone hitting a functional issue from this on 19.1.0.

CC @joe-img @preames @BeMg @lukel97 @nikic

[tru]

I am pretty sure this can be closed. re-open if that's not the case.