[PATCH] D149886: [ShrinkWrap] Allow shrinkwrapping past memory accesses to jump tables

[Jonathon Penix via Phabricator via llvm-commits]

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This patch adds a check for whether the memory operand is known to be
a jump table and, if so, allows shrinkwrapping to continue. In the
case that we are looking at a jump table, I believe it is safe to
assume that the access will not be to the stack (but please correct me
if I am wrong here).

In the test attached, this is helpful in that we are able to generate
only one instruction for each non-default case in the original switch
statement.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D149886

Files:
  llvm/lib/CodeGen/ShrinkWrap.cpp
  llvm/test/CodeGen/RISCV/shrinkwrap-jump-table.ll

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