[all-commits] [llvm/llvm-project] 4ed735: [IPSCCP] Use ParamState for arguments at call sites.

[Florian Hahn via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 4ed7355e4485486563ee31da2fb6e0c88d4ed076
      https://github.com/llvm/llvm-project/commit/4ed7355e4485486563ee31da2fb6e0c88d4ed076
  Author: Florian Hahn <flo at fhahn.com>
  Date:   2020-01-23 (Thu, 23 Jan 2020)

  Changed paths:
    M llvm/lib/Transforms/Scalar/SCCP.cpp
    M llvm/test/Transforms/SCCP/ip-constant-ranges.ll

  Log Message:
  -----------
  [IPSCCP] Use ParamState for arguments at call sites.

We currently use integer ranges to merge concrete function arguments.
We use the ParamState range for those, but we only look up concrete
values in the regular state. For concrete function arguments that are
themselves arguments of the containing function, we can use the param
state directly and improve the precision in some cases.

Besides improving the results in some cases, this is also a small step towards
switching to ValueLatticeElement, by allowing D60582 to be a NFC.

Reviewers: efriedma, davide

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D71836