[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:

> Can you just take the existing multiplier and apply it to the existing threshold without the new layer?

That is what currently is doing but apparently the threshold is not large enough for a large function even after the constant bonus applied.

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