[llvm] [Inliner] Don't apply the cold-callsite threshold in non-callable functions (PR #211255)

[Spencer Bryngelson via llvm-commits]

sbryngelson wrote:

Updated, thanks. The description still described the `TTI::applyColdCallSiteThreshold` hook from the first revision; it now describes the `isCallableCC` guard that is actually in the patch, and notes the hook was dropped in review.

Re-ran the suites on the current revision while I was in there: `llvm/test/Transforms`, `llvm/test/Analysis/InlineCost`, `llvm/test/CodeGen/AMDGPU`, 16596 tests, 14668 passed, 39 expected failures, no regression. The single failure, `Transforms/ThinLTOBitcodeWriter/no-type-md.ll`, is pre-existing and fails identically with the patch reverted.


https://github.com/llvm/llvm-project/pull/211255