This CL extends the smarter function-entry stack check logic (see
v8:9534) to OSR'd code. These smarter stack checks prevent
overflowing the stack during deoptimization.
The challenge for both function-entry (FE) and OSR-entry (OE) stack
checks is that there is no dedicated physical StackCheck to
deoptimize into. For more context: the physical StackCheck bytecode
was removed in crrev.com/c/1914218.
FE stack checks solve this by using a marker bailout id to signify
a deopt bytecode offset before the first bytecode.
In this CL, OE stack checks take a similar approach by using the
OSR'd loop's JumpLoop bytecode, which is conceptually immediately
before the OSR'd loop header.
When a stack overflow at an OE stack check occurs: %StackGuard
may cause a lazy deopt on return to the optimized OSR code,
causing re-execution of the JumpLoop handler in the
InterpreterEnterBytecodeAdvance builtin, ultimately continuing
execution the interpreter at the first bytecode of the OSR'd loop
header.
Bug: chromium:1034322, v8:9534
Change-Id: I1ae88a08702cde9a5eb84a451a9f1acc41204d5c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2625872
Auto-Submit: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72153}
8703c38d9a