This CL reinstates the trampoline for pushing the values of
callee-saved registers on the stack, which is used for stack scanning.
It reintroduces the set of architecture-specific functions
PushAllRegistersAndIterateStack, removed in crrev.com/c/3989143.
The reason for this change is that the simpler architecture-specific
functions SaveCalleeSavedRegisters failed to correctly save the
values of the registers, in the presence of C++ compiler optimizations.
It also removes the stack context, introduced in crrev.com/c/4017512,
and uses again the trampoline for iterating through the stack.
Bug: v8:13257
Change-Id: I9e656a9b3ba6616168602300f2180b4f340593f3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/4171639
Commit-Queue: Nikolaos Papaspyrou <nikolaos@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#85394}
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