[PATCH] D125787: [RISCV] Fix RVV stack frame alignment bugs

[Philip Reames via Phabricator via llvm-commits]

reames added a comment.

Thank you for a informative and well written patch description!

Reading through, it seems like your second bug mentioned could probably be reproduced and fixed independently of the others?  Would it make sense to split that into it's own patch?

One bit I don't understand the reasoning on is increasing minimal RVV alignment to 16 bytes.  You say that this makes it easier to reason about, but I don't really follow that.



================
Comment at: llvm/test/CodeGen/RISCV/rvv/rv32-spill-vector.ll:55
 ; SPILL-O0-NEXT:    csrr a0, vlenb
+; SPILL-O0-NEXT:    slli a0, a0, 1
 ; SPILL-O0-NEXT:    sub sp, sp, a0
----------------
Near as I can tell, these shifts are coming from the 16 byte minimum RVV alignment right?  Or is there some other cause I'm missing.

As noted in the top-level comment, I wonder if this is worthwhile.  


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D125787/new/

https://reviews.llvm.org/D125787