tree 2092966931acca2b1a936b082a5bac248c0604d1
parent 6e6f89a2558121e47ffcdbba17397e92c0cd9067
author Vyacheslav Egorov <vegorov@google.com> 1676575365 +0000
committer Commit Queue <dart-scoped@luci-project-accounts.iam.gserviceaccount.com> 1676575365 +0000

[vm/compiler] Stop pushing arguments in optimized code.

After this change we no longer push outgoing arguments for normal
Dart calls, but instead simply move them into an area reserved for
outgoing arguments at the top of the frame. This allows us to stop
mutating SP and avoid explicit Drop(argc) after each call.

There are still other places in the generated code where we
push something onto the stack either to free a temporary
register or spill a value across a slow-path call.

This is the first step towards switching to native SP on ARM64.

# Code Size Impact

I have tested this on a large internal application and got the
following size delta

## ARM

|        | Before   | After    | Delta   |       |
|--------|----------|----------|---------|-------|
| ROData | 6366632  | 6463680  | +97048  | +1.5% |
| Code   | 22714192 | 22043984 | -670208 | -2.9% |
| Total  | 33723701 | 33150477 | -573224 | -1.6% |

## ARM64

|        | Before   | After    | Delta   |       |
|--------|----------|----------|---------|-------|
| ROData | 7122032  | 7214288  | +92256  | +1.3% |
| Code   | 21607196 | 20741788 | -865408 | -4.0% |
| Total  | 33375769 | 32602544 | -773225 | -2.3% |

TEST=ci

Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-nnbd-linux-release-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64c-try,vm-kernel-precomp-linux-product-x64-try,vm-precomp-ffi-qemu-linux-release-riscv64-try,vm-precomp-ffi-qemu-linux-release-arm-try,vm-kernel-precomp-nnbd-linux-release-simarm64-try,vm-kernel-nnbd-linux-release-simarm64-try
Bug: https://github.com/dart-lang/sdk/issues/39083
Change-Id: Icace0c986285b9c16e41786cded44f88277bd25f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/282029
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>