[clang] [llvm] [NVPTX] Support i256 load/store with 256-bit vector load (PR #155198)

[Alex MacLean via llvm-commits]

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@@ -1506,3 +1506,98 @@ define void @local_volatile_4xdouble(ptr addrspace(5) %a, ptr addrspace(5) %b) {
   store volatile <4 x double> %a.load, ptr addrspace(5) %b
   ret void
 }
+
+define void @test_i256_global(ptr addrspace(1) %a, ptr addrspace(1) %b) {
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AlexMaclean wrote:

I think these tests are present at `@test_i256_generic` and `@generic_4xdouble`. They seem to be both lowered appropriately. 

https://github.com/llvm/llvm-project/pull/155198