[llvm] [AMDGPU] Don't DEALLOC_VGPRS from callable functions (PR #72245)

[Jannik Silvanus via llvm-commits]

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@@ -1924,6 +1924,10 @@ bool isChainCC(CallingConv::ID CC) {
   }
 }
 
+bool isCallableCC(CallingConv::ID CC) {
+  return !isEntryFunctionCC(CC) && !isChainCC(CC);
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jasilvanus wrote:

Why are we excluding the chain CC here?

With a chain CC, the previous function that chain-called us could have used scratch.

https://github.com/llvm/llvm-project/pull/72245