[llvm] [regalloc][LiveRegMatrix][AMDGPU] Fix LiveInterval dangling pointers in LiveRegMatrix. (PR #168556)

[Matt Arsenault via llvm-commits]

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@@ -191,7 +193,7 @@ class InlineSpiller : public Spiller {
       : MF(MF), LIS(Analyses.LIS), LSS(Analyses.LSS), VRM(VRM),
         MRI(MF.getRegInfo()), TII(*MF.getSubtarget().getInstrInfo()),
         TRI(*MF.getSubtarget().getRegisterInfo()), Matrix(Matrix),
-        HSpiller(Analyses, MF, VRM), VRAI(VRAI) {}
+        HSpiller(Analyses, MF, VRM, *Matrix), VRAI(VRAI) {}
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arsenm wrote:

Kind of a problem, but we don't handle PBQP today (e.g., it doesn't support the regalloc splitting) 

https://github.com/llvm/llvm-project/pull/168556