The stack check instruction sequence is pattern-matched in
instruction-selector-{ia32,x64}.cc and replaced with its own specialized
opcode, for which we later generate an efficient stack check in a single
instruction.

But this pattern matching has never worked for CSA-generated code. The
matcher expected LoadStackPointer in the right operand and the external
reference load in the left operand. CSA generated exactly vice-versa.

This CL does a few things; it
1. reverts the recent change to load the
limit from smi roots:

Revert "[csa] Load the stack limit from smi roots"
This reverts commit 507c29c9.

2. tweaks the CSA instruction sequence to output what the matcher
expects.
3. refactors stack check matching into a new StackCheckMatcher class.
4. typifies CSA::PerformStackCheck as a drive-by.

Bug: v8:6666,v8:7844
Change-Id: I9bb879ac10bfe7187750c5f9e7834dc4accf28b5
Reviewed-on: https://chromium-review.googlesource.com/1099068Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53737}