[llvm] [WebAssembly] Protect memory.fill and memory.copy from zero-length ranges. (PR #112617)

[Heejin Ahn via llvm-commits]

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@@ -54,3 +52,10 @@ HANDLE_MEM_NODETYPE(GLOBAL_GET)
 HANDLE_MEM_NODETYPE(GLOBAL_SET)
 HANDLE_MEM_NODETYPE(TABLE_GET)
 HANDLE_MEM_NODETYPE(TABLE_SET)
+
+// Bulk memory instructions. These follow LLVM's expected semantics of
+// supporting out-of-bounds pointers if the length is zero, by insertig
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aheejin wrote:

```suggestion
// supporting out-of-bounds pointers if the length is zero, by inserting
```

https://github.com/llvm/llvm-project/pull/112617