Reapplies 142c28ffa1323e9a8d53200a22c80d5d778e0d0f as part of D140242 which got reverted due to amdgpu openmp test failures.
This diff fixes said failures by eliding most of `adjustInliningThresholdUsingCallee` for indirect calls as the callee function is unavailable for indirect calls.
Reviewed By: arsenm, #amdgpu
Differential Revision: https://reviews.llvm.org/D143498
A regression from when new PM got enabled as default. Functions with a big number of instructions will elide getting inlined but do not consider the cost of passing arguments over stack if there are a lot of function arguments. This patch attempts to add a heuristic for AMDGPU's function calling convention that also considers function arguments passed through the stack.
Reviewed By: #amdgpu, arsenm
Differential Revision: https://reviews.llvm.org/D140242