[llvm] [AMDGPU] Move WWM register pre-allocation to during regalloc (PR #70618)

[Matt Arsenault via llvm-commits]

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@@ -101,7 +99,7 @@ bool SIPreAllocateWWMRegs::processDef(MachineOperand &MO) {
   LiveInterval &LI = LIS->getInterval(Reg);
 
   for (MCRegister PhysReg : RegClassInfo.getOrder(MRI->getRegClass(Reg))) {
-    if (!MRI->isPhysRegUsed(PhysReg) &&
+    if (!MRI->isPhysRegUsed(PhysReg, true) &&
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arsenm wrote:

Add the /**/ comment for the true parameter name, I have no idea what this does without looking

https://github.com/llvm/llvm-project/pull/70618