Stream: git-wasmtime

Topic: wasmtime / PR #7699 PCC [AArch64]: load_constant64_full g...

Wasmtime GitHub notifications bot (Dec 18 2023 at 09:03):

feilongjiang opened PR #7699 from feilongjiang:fix_arm64_pcc_on_32bit_movn to bytecodealliance:main:

Hi team, find another PCC fact range issue on AArch64.
When the top 32 bits of the value are zero and the upper_halfword of the lower 32 bits is u16::MAX, load_constant64_full will emit a single movn instruction. In that case, add_range_fact only adds lower_halfword as the fact range, which misses the upper halfword value. We should add the hole 32-bit value as the fact range.

Here is a simple test to reproduce the issue:

;; test_const.wat
(module
  (func (export "test_constant") (result i64) (i64.const 0xfffffff7))
)

Step to reproduce:

Compile the test with PCC on:

target/debug/wasmtime compile -C pcc=y test_const.wat

the output will be:

Error: Compilation error: Proof-carrying-code validation error: UnsupportedFact

<!--
Please make sure you include the following information:

• If this work has been discussed elsewhere, please include a link to that
  conversation. If it was discussed in an issue, just mention "issue #...".

• Explain why this change is needed. If the details are in an issue already,
  this can be brief.

Our development process is documented in the Wasmtime book:
https://docs.wasmtime.dev/contributing-development-process.html

Please ensure all communication follows the code of conduct:
https://github.com/bytecodealliance/wasmtime/blob/main/CODE_OF_CONDUCT.md
-->

Wasmtime GitHub notifications bot (Dec 18 2023 at 09:03):

feilongjiang requested abrown for a review on PR #7699.

Wasmtime GitHub notifications bot (Dec 18 2023 at 09:03):

feilongjiang requested wasmtime-compiler-reviewers for a review on PR #7699.

Wasmtime GitHub notifications bot (Dec 18 2023 at 09:06):

feilongjiang commented on PR #7699:

Hi @fitzgen, would you please take a look?

Wasmtime GitHub notifications bot (Dec 18 2023 at 11:44):

github-actions[bot] commented on PR #7699:

Subscribe to Label Action

cc @cfallin, @fitzgen

<details>
This issue or pull request has been labeled: "cranelift", "cranelift:area:aarch64", "isle"

Thus the following users have been cc'd because of the following labels:

• cfallin: isle
• fitzgen: isle

To subscribe or unsubscribe from this label, edit the <code>.github/subscribe-to-label.json</code> configuration file.

Learn more.
</details>

Wasmtime GitHub notifications bot (Dec 20 2023 at 19:10):

fitzgen submitted PR review:

Thanks!

Wasmtime GitHub notifications bot (Dec 20 2023 at 19:39):

fitzgen merged PR #7699.

Last updated: Dec 23 2024 at 13:07 UTC