[llvm] [MIR] Allow overriding isSSA, noPhis, noVRegs in MIR input (PR #108546)

[Dominik Montada via llvm-commits]

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@@ -2,11 +2,13 @@
 # RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -run-pass=early-tailduplication -verify-machineinstrs -o - %s | FileCheck %s
 
  # There are no phis in this testcase. Early tail duplication introduces them,
- # so the NoPHIs property needs to be cleared to avoid verifier errors
+ # so the NoPHIs property needs to be set explicitly to false to avoid verifier
+ # errors
 
 ---
 name:           tail_duplicate_nophis
 tracksRegLiveness: true
+noPhis: false
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gargaroff wrote:

Uhhh, good question. I think I added this by accident after getting overly excited by the comment in the beginning of the test.

No idea where that property is being cleared to make the test work to be honest...

https://github.com/llvm/llvm-project/pull/108546