[llvm] [AMDGPU][NFC] Move InstCounterType and Waitcnt to SIInsertWaitcnts.h (PR #187823)

[Matt Arsenault via llvm-commits]

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@@ -1348,27 +1242,6 @@ unsigned getXcntBitMask(const IsaVersion &Version);
 /// depends on the ISA version.
 unsigned getStorecntBitMask(const IsaVersion &Version);
 
-// The following are only meaningful on targets that support
-// S_WAIT_LOADCNT_DSCNT and S_WAIT_STORECNT_DSCNT.
-
-/// \returns Decoded Waitcnt structure from given \p LoadcntDscnt for given
-/// isa \p Version.
-Waitcnt decodeLoadcntDscnt(const IsaVersion &Version, unsigned LoadcntDscnt);
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arsenm wrote:

I'd prefer to keep these where they are with all of the other encode/decode utilities 

https://github.com/llvm/llvm-project/pull/187823