[clang] [Clang][SYCL] Introduce clang-sycl-linker to link SYCL offloading device code (Part 1 of many) (PR #112245)

[Alexey Bader via cfe-commits]

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@@ -0,0 +1,42 @@
+// Tests the clang-sycl-linker tool.
+//
+// Test a simple case without arguments.
+// RUN: %clangxx -fsycl -emit-llvm -c %s -o %t.bc
+// RUN: clang-sycl-linker --dry-run -triple spirv64 %t.bc -o a.spv 2>&1 \
+// RUN:   | FileCheck %s --check-prefix=SIMPLE
+// SIMPLE: "{{.*}}llvm-link{{.*}}" {{.*}}.bc -o [[FIRSTLLVMLINKOUT:.*]].bc --suppress-warnings
+// SIMPLE-NEXT: "{{.*}}llvm-spirv{{.*}}" {{.*}}-o a.spv [[FIRSTLLVMLINKOUT]].bc
+//
+// Test a simple case with device library files specified.
+// RUN: echo ' ' > %T/lib1.bc
+// RUN: echo ' ' > %T/lib2.bc
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bader wrote:

```suggestion
// RUN: touch %T/lib1.bc
// RUN: touch %T/lib2.bc
```
Can we leave these files empty?

https://github.com/llvm/llvm-project/pull/112245