This is a reland of commit 491de34b

co-authors: Ji Qiu <qiuji@iscas.ac.cn>
            Alvise De Faveri Tron <elvisilde@gmail.com>
            Usman Zain <uszain@gmail.com>
            Zheng Quan <vitalyankh@gmail.com>

Original change's description:
> [riscv32] Add RISCV32 backend
>
> This very large changeset adds support for RISCV32.
>
> Bug: v8:13025
> Change-Id: Ieacc857131e6620f0fcfd7daa88a0f8d77056aa9
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3736732
> Reviewed-by: Michael Achenbach <machenbach@chromium.org>
> Commit-Queue: Yahan Lu <yahan@iscas.ac.cn>
> Reviewed-by: ji qiu <qiuji@iscas.ac.cn>
> Reviewed-by: Andreas Haas <ahaas@chromium.org>
> Reviewed-by: Hannes Payer <hpayer@chromium.org>
> Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#82053}

Bug: v8:13025
Change-Id: I220fae4b8e2679bdc111724e08817b079b373bd5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3807124
Commit-Queue: Yahan Lu <yahan@iscas.ac.cn>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: ji qiu <qiuji@iscas.ac.cn>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/main@{#82198}

This reverts commit 491de34b.

Reason for revert: Lose co-authors information

Original change's description:
> [riscv32] Add RISCV32 backend
>
> This very large changeset adds support for RISCV32.
>
> Bug: v8:13025
> Change-Id: Ieacc857131e6620f0fcfd7daa88a0f8d77056aa9
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3736732
> Reviewed-by: Michael Achenbach <machenbach@chromium.org>
> Commit-Queue: Yahan Lu <yahan@iscas.ac.cn>
> Reviewed-by: ji qiu <qiuji@iscas.ac.cn>
> Reviewed-by: Andreas Haas <ahaas@chromium.org>
> Reviewed-by: Hannes Payer <hpayer@chromium.org>
> Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#82053}

Bug: v8:13025
Change-Id: I6abea32c8ea43b080a938782dc643c97a123f1d8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3803994Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Owners-Override: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: ji qiu <qiuji@iscas.ac.cn>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Yahan Lu <yahan@iscas.ac.cn>
Cr-Commit-Position: refs/heads/main@{#82163}

This very large changeset adds support for RISCV32.

Bug: v8:13025
Change-Id: Ieacc857131e6620f0fcfd7daa88a0f8d77056aa9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3736732Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Yahan Lu <yahan@iscas.ac.cn>
Reviewed-by: ji qiu <qiuji@iscas.ac.cn>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Cr-Commit-Position: refs/heads/main@{#82053}

Bug: v8:12008
Change-Id: I2e1d918a1370dae1e15919fbf02d69cbe48f63bf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3089095Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#76308}

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}

Bug: v8:10799
Change-Id: Id912520b6a27e439e204bac47c0723a8f613be4b
Fixed: v8:10799
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2472000
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70656}