[all-commits] [llvm/llvm-project] 176249: [CodeGen][TailDuplicator] Don't duplicate blocks w...

[Bill Wendling via All-commits]

  Branch: refs/heads/release/11.x
  Home:   https://github.com/llvm/llvm-project
  Commit: 176249bd6732a8044d457092ed932768724a6f06
      https://github.com/llvm/llvm-project/commit/176249bd6732a8044d457092ed932768724a6f06
  Author: Bill Wendling <isanbard at gmail.com>
  Date:   2020-10-07 (Wed, 07 Oct 2020)

  Changed paths:
    M llvm/lib/CodeGen/TailDuplicator.cpp
    A llvm/test/CodeGen/X86/tail-dup-asm-goto.ll

  Log Message:
  -----------
  [CodeGen][TailDuplicator] Don't duplicate blocks with INLINEASM_BR

Tail duplication of a block with an INLINEASM_BR may result in a PHI
node on the indirect branch. This is okay, but it also introduces a copy
for that PHI node *after* the INLINEASM_BR, which is not okay.

See: https://github.com/ClangBuiltLinux/linux/issues/1125

Differential Revision: https://reviews.llvm.org/D88823

(cherry picked from commit d2c61d2bf9bd1efad49acba2f2751112522686aa)