[llvm] [amdgpu] Add llvm.amdgcn.init.whole.wave intrinsic (PR #105822)

[Nicolai Hähnle via llvm-commits]

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@@ -1582,6 +1583,28 @@ void SIWholeQuadMode::lowerInitExec(MachineInstr &MI) {
   MachineBasicBlock *MBB = MI.getParent();
   bool IsWave32 = ST->isWave32();
 
+  if (MI.getOpcode() == AMDGPU::SI_INIT_WHOLE_WAVE) {
+    // TODO: Assert that it's in the entry block
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nhaehnle wrote:

Do the TODO? :)

https://github.com/llvm/llvm-project/pull/105822