This very large changeset adds support for RISC-V.

Bug: v8:10991
Change-Id: Ic997c94cc12bba6881bc208e66526f423dd0679c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2571344
Commit-Queue: Brice Dobry <brice.dobry@futurewei.com>
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72598}

"std/stw" must always store to a memory address.
Destination cannot be another register.

Change-Id: I424bd535033937b3876f58ca5a4530aeac43e182
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2476064Reviewed-by: Junliang Yan <junyan@redhat.com>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Milad Fa <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/master@{#70540}

Change-Id: Icd094eaa12b957bc7a658807aaa565665a184c81
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2470561
Commit-Queue: Victor Gomes <victorgomes@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Auto-Submit: Victor Gomes <victorgomes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70499}

This is a reland of 3593ee83

The MSAN doesn't seem to be considering initializing stores via inline
assembly as such (in a new cctest helper GetStackPointer()), so this
reland attempt fixes the issue and ensures that the MSAN bot is happy.

Original change's description:
> Reland "[csa] Fix semantics of PopAndReturn"
>
> This is a reland of 5e5eaf79
>
> This CL fixes the "function returns address of local variable" issue
> which GCC was complaining about by using inline assembly instead of
> address of a local for getting stack pointer approximation.
>
> Original change's description:
> > [csa] Fix semantics of PopAndReturn
> >
> > This CL prohibits using PopAndReturn from the builtins that
> > have calling convention with arguments on the stack.
> >
> > This CL also updates the PopAndReturn tests so that even off-by-one
> > errors in the number of poped arguments are caught which was not the
> > case before.
> >
> > Motivation:
> >
> > PopAndReturn is supposed to be using ONLY in CSA/Torque builtins for
> > dropping ALL JS arguments that are currently located on the stack.
> > Disallowing PopAndReturn in builtins with stack arguments simplifies
> > semantics of this instruction because in case of presence of declared
> > stack parameters it's impossible to distinguish the following cases:
> > 1) stack parameter is included in JS arguments (and therefore it will
> >    be dropped as a part of 'pop' number of arguments),
> > 2) stack parameter is NOT included in JS arguments (and therefore it
> >    should be dropped in ADDITION to the 'pop' number of arguments).
> >
> > This issue wasn't noticed before because builtins with stack parameters
> > relied on adapter frames machinery to ensure that the expected
> > parameters are present on the stack, but on the same time the adapter
> > frame tearing down code was effectively recovering the stack pointer
> > potentially broken by the CSA builtin.
> >
> > Once we get rid of the arguments adapter frames keeping stack pointer
> > in a valid state becomes crucial.
> >
> > Bug: v8:5269, v8:10201
> > Change-Id: Id3ea9730bb0d41d17999c73136c4dfada374a822
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2460819
> > Commit-Queue: Igor Sheludko <ishell@chromium.org>
> > Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#70454}
>
> Tbr: tebbi@chromium.org
> Bug: v8:5269
> Bug: v8:10201
> Change-Id: Ic1a05fcc4efd2068538bff28189545cfd2617d9b
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2465839
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Victor Gomes <victorgomes@chromium.org>
> Commit-Queue: Igor Sheludko <ishell@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#70483}

Tbr: tebbi@chromium.org
Cq-Include-Trybots: luci.v8.try:v8_linux64_msan_rel_ng
Bug: v8:5269
Bug: v8:10201
Change-Id: Ib09af2d1260bb42ac26aabface14e6b83b3efec4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2467847
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Victor Gomes <victorgomes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70492}

This reverts commit 3593ee83.

Reason for revert: MSan issues: https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20-%20arm64%20-%20sim%20-%20MSAN/34798

Original change's description:
> Reland "[csa] Fix semantics of PopAndReturn"
>
> This is a reland of 5e5eaf79
>
> This CL fixes the "function returns address of local variable" issue
> which GCC was complaining about by using inline assembly instead of
> address of a local for getting stack pointer approximation.
>
> Original change's description:
> > [csa] Fix semantics of PopAndReturn
> >
> > This CL prohibits using PopAndReturn from the builtins that
> > have calling convention with arguments on the stack.
> >
> > This CL also updates the PopAndReturn tests so that even off-by-one
> > errors in the number of poped arguments are caught which was not the
> > case before.
> >
> > Motivation:
> >
> > PopAndReturn is supposed to be using ONLY in CSA/Torque builtins for
> > dropping ALL JS arguments that are currently located on the stack.
> > Disallowing PopAndReturn in builtins with stack arguments simplifies
> > semantics of this instruction because in case of presence of declared
> > stack parameters it's impossible to distinguish the following cases:
> > 1) stack parameter is included in JS arguments (and therefore it will
> >    be dropped as a part of 'pop' number of arguments),
> > 2) stack parameter is NOT included in JS arguments (and therefore it
> >    should be dropped in ADDITION to the 'pop' number of arguments).
> >
> > This issue wasn't noticed before because builtins with stack parameters
> > relied on adapter frames machinery to ensure that the expected
> > parameters are present on the stack, but on the same time the adapter
> > frame tearing down code was effectively recovering the stack pointer
> > potentially broken by the CSA builtin.
> >
> > Once we get rid of the arguments adapter frames keeping stack pointer
> > in a valid state becomes crucial.
> >
> > Bug: v8:5269, v8:10201
> > Change-Id: Id3ea9730bb0d41d17999c73136c4dfada374a822
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2460819
> > Commit-Queue: Igor Sheludko <ishell@chromium.org>
> > Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#70454}
>
> Tbr: tebbi@chromium.org
> Bug: v8:5269
> Bug: v8:10201
> Change-Id: Ic1a05fcc4efd2068538bff28189545cfd2617d9b
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2465839
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Victor Gomes <victorgomes@chromium.org>
> Commit-Queue: Igor Sheludko <ishell@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#70483}

TBR=tebbi@chromium.org,ishell@chromium.org,victorgomes@chromium.org

Change-Id: Icbd71d744a519a58e49feb917109228631b9d9a3
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:5269
Bug: v8:10201
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2467846Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70485}

This is a reland of 5e5eaf79

This CL fixes the "function returns address of local variable" issue
which GCC was complaining about by using inline assembly instead of
address of a local for getting stack pointer approximation.

Original change's description:
> [csa] Fix semantics of PopAndReturn
>
> This CL prohibits using PopAndReturn from the builtins that
> have calling convention with arguments on the stack.
>
> This CL also updates the PopAndReturn tests so that even off-by-one
> errors in the number of poped arguments are caught which was not the
> case before.
>
> Motivation:
>
> PopAndReturn is supposed to be using ONLY in CSA/Torque builtins for
> dropping ALL JS arguments that are currently located on the stack.
> Disallowing PopAndReturn in builtins with stack arguments simplifies
> semantics of this instruction because in case of presence of declared
> stack parameters it's impossible to distinguish the following cases:
> 1) stack parameter is included in JS arguments (and therefore it will
>    be dropped as a part of 'pop' number of arguments),
> 2) stack parameter is NOT included in JS arguments (and therefore it
>    should be dropped in ADDITION to the 'pop' number of arguments).
>
> This issue wasn't noticed before because builtins with stack parameters
> relied on adapter frames machinery to ensure that the expected
> parameters are present on the stack, but on the same time the adapter
> frame tearing down code was effectively recovering the stack pointer
> potentially broken by the CSA builtin.
>
> Once we get rid of the arguments adapter frames keeping stack pointer
> in a valid state becomes crucial.
>
> Bug: v8:5269, v8:10201
> Change-Id: Id3ea9730bb0d41d17999c73136c4dfada374a822
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2460819
> Commit-Queue: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#70454}

Tbr: tebbi@chromium.org
Bug: v8:5269
Bug: v8:10201
Change-Id: Ic1a05fcc4efd2068538bff28189545cfd2617d9b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2465839Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Victor Gomes <victorgomes@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70483}