[llvm] [AMDGPU] Insert waitcnt for non-global fence release in GFX12 (PR #159282)

[Sameer Sahasrabuddhe via llvm-commits]

================
@@ -2522,8 +2522,7 @@ bool SIGfx12CacheControl::insertRelease(MachineBasicBlock::iterator &MI,
   // sequentially consistent, and no other thread can access scratch
   // memory.
 
-  // Other address spaces do not have a cache.
-  if ((AddrSpace & SIAtomicAddrSpace::GLOBAL) == SIAtomicAddrSpace::NONE)
+  if (AddrSpace == SIAtomicAddrSpace::SCRATCH)
     return false;
 
----------------
ssahasra wrote:

The original code had an early return on a negative condition which matched the one in `insertAcquire()`. Why change it and move all the code inside a positive condition? That seems to have introduced a lot of whitespace noise due to reindentation.

https://github.com/llvm/llvm-project/pull/159282