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

[Shilei Tian via llvm-commits]

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@@ -240,6 +240,11 @@ class GCNTTIImpl final : public BasicTTIImplBase<GCNTTIImpl> {
   bool areInlineCompatible(const Function *Caller,
                            const Function *Callee) const;
 
+  int getInliningLastCallToStaticBonus() const {
+    // InlineConstants::LastCallToStaticBonus * 11 where 11 is AMDGPU's inlining
+    // threshold multiplier.
+    return 165000;
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shiltian wrote:

I don't think the multiplier was already applied to other bonuses. For example, `VectorBonus` has a TTI function `getInlinerVectorBonusPercent` to determine the "multiplier".

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