[MetaSchedule] Fix tune_tir crash with ScheduleError in RewriteParallelVectorizeUnroll

[Dayuxiaoshui]

This patch fixes issue #18423 where meta_schedule.tune_tir crashes during initial population sampling when RewriteParallelVectorizeUnroll postprocessor encounters blocks that violate compact dataflow requirements.

The crash occurred when:

• A block reads and writes to the same buffer
• RewriteParallelVectorizeUnroll tries to parallelize/vectorize these loops
• ScheduleError is thrown and propagates through parallel_for_dynamic

Solution:

• Added exception handling in RewriteParallelVectorizeUnroll::Apply to catch ScheduleError and skip problematic blocks instead of crashing
• Added exception handling in ThreadedTraceApply::Apply to catch exceptions from postprocessors and treat them as normal failures

This makes the tuning process more robust by gracefully handling schedule errors instead of crashing the entire tuning session.

[gemini-code-assist[bot]]

Summary of Changes

Hello @Dayuxiaoshui, I'm Gemini Code Assist[^1]! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly improves the stability and resilience of the MetaSchedule tuning process. It specifically targets and resolves a critical crash that occurred when the RewriteParallelVectorizeUnroll postprocessor encountered un-schedulable blocks, such as those with conflicting read/write operations on the same buffer. By introducing robust exception handling within both the postprocessor itself and the ThreadedTraceApply utility, the system can now gracefully manage and log these scheduling failures, allowing the tuning session to continue without interruption, thereby enhancing the overall user experience and reliability.

Highlights

• Crash Fix: Addresses a crash in meta_schedule.tune_tir during initial population sampling.
• Root Cause: The crash was due to RewriteParallelVectorizeUnroll encountering blocks that violate compact dataflow requirements, specifically when a block reads and writes to the same buffer, leading to a ScheduleError.
• Solution in Postprocessor: Implemented try-catch blocks in RewriteParallelVectorizeUnroll::Apply to catch ScheduleError and skip problematic blocks, preventing crashes.
• Robustness in Utility: Added broader exception handling in ThreadedTraceApply::Apply to catch any ScheduleError or std::exception from postprocessors, treating them as graceful failures instead of crashes.

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[Dayuxiaoshui]

@tlopex