[clang] [clang][SPIR][SPIRV] Don't generate constant NULL from addrspacecast generic NULL (PR #165353)

[Matt Arsenault via cfe-commits]

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+// RUN: %clang_cc1 -no-enable-noundef-analysis %s -cl-std=CL2.0 -include opencl-c.h -triple spir64 -emit-llvm -o - | FileCheck %s
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arsenm wrote:

Test name is very broad for what this is testing. Can you merge this with an existing null test, or make this more comprehensive for all the address spaces (I thought we had one of those somewhere already, at least with amdgp run lines)

https://github.com/llvm/llvm-project/pull/165353