[llvm] [AMDGPU] Add new cache flushing instructions for GFX12 (PR #76944)

[Matt Arsenault via llvm-commits]

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@@ -2132,6 +2142,62 @@ bool SIGfx11CacheControl::enableVolatileAndOrNonTemporal(
   return Changed;
 }
 
+bool SIGfx12CacheControl::insertAcquire(MachineBasicBlock::iterator &MI,
+                                        SIAtomicScope Scope,
+                                        SIAtomicAddrSpace AddrSpace,
+                                        Position Pos) const {
+  if (!InsertCacheInv)
+    return false;
+
+  MachineBasicBlock &MBB = *MI->getParent();
+  DebugLoc DL = MI->getDebugLoc();
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arsenm wrote:

const ref 

https://github.com/llvm/llvm-project/pull/76944