[llvm] AMDGPU: Don't save FP/BP for noreturn functions (PR #187668)

[Scott Linder via llvm-commits]

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@@ -586,6 +586,9 @@ class SIMachineFunctionInfo final : public AMDGPUMachineFunctionInfo,
 
   bool IsWholeWaveFunction = false;
 
+  // True if the function does not return to the caller.
+  bool DoesNotReturn = false;
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slinder1 wrote:

As an aside, what is your litmus test for this? Just above this is `IsWholeWaveFunction`, which also seems to be an immutable property of the IR function. Was that a mistake to serialize, or is there some other rationale for it?

https://github.com/llvm/llvm-project/pull/187668