[llvm] [ConstantRange] Bail out early in unsignedMulMayOverflow for wide integer types (PR #192275)

[Alexis Engelke via llvm-commits]

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@@ -157,6 +157,10 @@ As a result, alignment is mandatory for atomic loads and stores.
 Other Things to Consider
 ^^^^^^^^^^^^^^^^^^^^^^^^
 
+#. Avoid emitting extremely wide integer types unless necessary.
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aengelke wrote:

```suggestion
#. Avoid emitting extremely wide integer types.
```

I can't think of any situation where this is necessary. It's also not just APInt that's not built for this, it's also that the code we emit for large bitwidths is a less efficient than what would be provided by a bignum library.

https://github.com/llvm/llvm-project/pull/192275