[llvm] [Sched] Skip MemOp with unknown size when clustering (PR #118443)

[Pengcheng Wang via llvm-commits]

https://github.com/wangpc-pp created https://github.com/llvm/llvm-project/pull/118443

In #83875, we changed the type of `Width` to `LocationSize`. To get
the clsuter bytes, we use `LocationSize::getValue()` to calculate
the value.

But when `Width` is an unknown size `LocationSize`, an assertion
"Getting value from an unknown LocationSize!" will be triggered.

This patch simply skips MemOp with unknown size to fix this issue
and keep the logic the same as before.

This issue was found when implementing software pipieliner for
RISC-V in #117546. The pipeliner may clone some memory operations
with `BeforeOrAfterPointer` size.


>From 893ed4831eb8c10bc603463d40c9da155e611194 Mon Sep 17 00:00:00 2001
From: Wang Pengcheng <wangpengcheng.pp at bytedance.com>
Date: Tue, 3 Dec 2024 16:24:47 +0800
Subject: [PATCH] [Sched] Skip MemOp with unknown size when clustering

In #83875, we changed the type of `Width` to `LocationSize`. To get
the clsuter bytes, we use `LocationSize::getValue()` to calculate
the value.

But when `Width` is an unknown size `LocationSize`, an assertion
"Getting value from an unknown LocationSize!" will be triggered.

This patch simply skips MemOp with unknown size to fix this issue
and keep the logic the same as before.

This issue was found when implementing software pipieliner for
RISC-V in #117546. The pipeliner may clone some memory operations
with `BeforeOrAfterPointer` size.
---
 llvm/lib/CodeGen/MachineScheduler.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/llvm/lib/CodeGen/MachineScheduler.cpp b/llvm/lib/CodeGen/MachineScheduler.cpp
index 23e5e4a4da6d9a..7da9b3a9c27651 100644
--- a/llvm/lib/CodeGen/MachineScheduler.cpp
+++ b/llvm/lib/CodeGen/MachineScheduler.cpp
@@ -1947,6 +1947,9 @@ void BaseMemOpClusterMutation::collectMemOpRecords(
     LocationSize Width = 0;
     if (TII->getMemOperandsWithOffsetWidth(MI, BaseOps, Offset,
                                            OffsetIsScalable, Width, TRI)) {
+      if (!Width.hasValue())
+        continue;
+
       MemOpRecords.push_back(
           MemOpInfo(&SU, BaseOps, Offset, OffsetIsScalable, Width));