[llvm] [TTI][AMDGPU] Allow targets to adjust `LastCallToStaticBonus` via `getInliningLastCallToStaticBonus` (PR #111311)

[Shilei Tian via llvm-commits]

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@@ -352,6 +352,9 @@ class TargetTransformInfo {
   unsigned getInliningCostBenefitAnalysisSavingsMultiplier() const;
   unsigned getInliningCostBenefitAnalysisProfitableMultiplier() const;
 
+  /// \returns The bonus of inlining the last call to a static function.
+  int getInliningLastCallToStaticBonus() const;
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shiltian wrote:

I'm not sure if it makes sense to use `unsigned` as return value, but `InlineConstants::LastCallToStaticBonus` is `int`.

https://github.com/llvm/llvm-project/pull/111311