[PATCH] D149342: [RISCV] Add test describing constant materialisation problem in loops

[Luke Lau via Phabricator via llvm-commits]

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As @alexey-bataev noticed, with the current cost model we account for
the cost of constant materialisation through the user's instruction
cost.
For straight line code this is usually fine, but inside a loop these
constants are usually hoisted out by LICM.
They should probably not be accounted for in these cases.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D149342

Files:
  llvm/test/Analysis/CostModel/RISCV/const-loop.ll

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