Temporarily Revert "[CostModel] remove cost-kind predicate for intrinsics in basic...

Temporarily Revert "[CostModel] remove cost-kind predicate for intrinsics in basic TTI implementation"
as it's causing crashes in the optimizer. A reduced testcase has been posted as a follow-up.

This reverts commit f7eac51b9b3f780c96ca41913293851c5acb465b.

Temporarily Revert "[CostModel] make default size cost for libcalls small (again)" as it depends upon the primary revert.

This reverts commit 8ec7ea3ddce7379e13e8dfb4a5260a6d2004aa1c.

Temporarily Revert "[CostModel] add tests for math library calls; NFC" as it depends upon the primary revert.

This reverts commit df09f825995b10da03f148133c119f52c94fd6e4.

Temporarily Revert "[LoopUnroll] add test for full unroll that is sensitive to cost-model; NFC" as it depends upon the primary revert.

This reverts commit 618d555e8d926a83161774df2035519c387269db.