[llvm] [AMDGPU] Infer amdgpu-no-flat-scratch-init attribute in AMDGPUAttributor (PR #94647)

[Matt Arsenault via llvm-commits]

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@@ -1040,12 +1040,8 @@ GCNUserSGPRUsageInfo::GCNUserSGPRUsageInfo(const Function &F,
   const CallingConv::ID CC = F.getCallingConv();
   const bool IsKernel =
       CC == CallingConv::AMDGPU_KERNEL || CC == CallingConv::SPIR_KERNEL;
-  // FIXME: Should have analysis or something rather than attribute to detect
-  // calls.
-  const bool HasCalls = F.hasFnAttribute("amdgpu-calls");
-  // FIXME: This attribute is a hack, we just need an analysis on the function
-  // to look for allocas.
-  const bool HasStackObjects = F.hasFnAttribute("amdgpu-stack-objects");
+  const bool NoFlatScratchInit =
+      F.hasFnAttribute("amdgpu-no-flat-scratch-init");
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arsenm wrote:

can sink this down to the use 

https://github.com/llvm/llvm-project/pull/94647