[llvm] [SelectionDAG] Fix a false assumption that there will always be a valid integer type corresponding to a vector type (PR #96658)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,13 @@
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx942 %s -o -
+
+define void @no_corresponding_integer_type(i8 %arg, ptr addrspace(1) %ptr) {
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RKSimon wrote:

I realise this is a crash test, but its still nice to use FileCheck and check the codegen

https://github.com/llvm/llvm-project/pull/96658