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

[Jay Foad 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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jayfoad wrote:

How did this test work before you added this line?

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