[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 +1,13 @@
+// Tests the driver when linking LLVM IR bitcode files and targeting SPIR-V
+// architecture.
+//
+// RUN: touch %t.bc
+// RUN: %clangxx --target=spirv64 --sycl-link -### %t.bc 2>&1 \
+// RUN:   | FileCheck %s -check-prefix=LINK
+// LINK: "{{.*}}clang-sycl-linker{{.*}}" "{{.*}}.bc" "-o" "a.out"
+//
+// Test that -Xlinker options are being passed to clang-sycl-linker.
+// RUN: %clangxx -### --target=spirv64 --sycl-link -Xlinker --llvm-spirv-path=/tmp \
+// RUN:   -Xlinker --library-path=/tmp -Xlinker --device-libs=lib1.bc,lib2.bc %t.bc 2>&1 \
+// RUN:   | FileCheck %s -check-prefix=XLINKEROPTS
+// XLINKEROPTS: "{{.*}}clang-sycl-linker{{.*}}" "--llvm-spirv-path=/tmp" "--library-path=/tmp" "--device-libs=lib1.bc,lib2.bc" "{{.*}}.bc" "-o" "a.out"
----------------
bader wrote:

This test case seems to cover everything that's checked in the previous test case. Can we drop the previous test case and leave only this one?
```suggestion
// RUN: %clangxx -### --target=spirv64 --sycl-link -Xlinker --llvm-spirv-path=/tmp \
// RUN:   -Xlinker --library-path=/tmp -Xlinker --device-libs=lib1.bc,lib2.bc %t.bc 2>&1 \
// RUN:   | FileCheck %s
// CHECK: "{{.*}}clang-sycl-linker{{.*}}" "--llvm-spirv-path=/tmp" "--library-path=/tmp" "--device-libs=lib1.bc,lib2.bc" "{{.*}}.bc" "-o" "a.out"
```

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