[clang] [CIR] Upstream `AddressSpace` support for `PointerType` (PR #161028)

[David Rivera via cfe-commits]

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@@ -2298,14 +2298,23 @@ mlir::LogicalResult CIRToLLVMSelectOpLowering::matchAndRewrite(
   return mlir::success();
 }
 
+static unsigned
+getTargetAddrSpaceFromCIRAddrSpace(cir::AddressSpace addrSpace) {
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RiverDave wrote:

Can you be a bit more specific? Besides numerical addresses to which I've added tests for in this PR. offload addresses cannot be lowered to LLVM since we seem to be dependend on `cir::lowerModule` which we haven't upstreamed yet. therefore we hit an assertion in this function. I could target that in a different PR.

https://github.com/llvm/llvm-project/pull/161028