Drain MTE before tnotify

[zhangstevenunity]

Summary

• Insert pipe_barrier(PIPE_ALL) before lowering pto.comm.tnotify to pto::comm::TNOTIFY.
• Add a lit regression covering tload/tstore followed by tnotify.
• Document the tnotify lowering guarantee.

Fixes #711

Tests

• ninja -C build-main-wsl tools/ptoas/ptoas
• build-main-wsl/tools/ptoas/ptoas --pto-arch=a3 test/lit/pto/issue711_tnotify_mte_drain.pto -o - 2>&1 | FileCheck test/lit/pto/issue711_tnotify_mte_drain.pto
• build-main-wsl/tools/ptoas/ptoas --pto-arch=a3 test/lit/pto/comm_p2p_emitc.pto -o - 2>&1 | FileCheck test/lit/pto/comm_p2p_emitc.pto --check-prefix=A3

[gemini-code-assist]

Code Review

This pull request ensures that pto.comm.tnotify lowering emits a pipe_barrier(PIPE_ALL) before calling pto::comm::TNOTIFY to drain prior MTE-side loads and stores. This change is implemented in PTOToEmitC.cpp, documented in PTO_IR_manual.md, and verified with a new LIT test. I have no feedback to provide as there are no review comments.

[reedhecre]

Codex Review

该评论由 review 机器人自动更新。

• PR: Drain MTE before tnotify #712 Drain MTE before tnotify
• Author: zhangstevenunity
• Base/Head: main / codex/issue711-tnotify-mte-drain
• Head SHA: 331e0c4227b7
• Trigger: 检测到新的 open PR
• Generated At: 2026-05-27T10:16:08Z
• Status: completed

Summary

未检查到 PR #712 存在问题

Findings

No issues found.