[clang] [clang][Driver][SPIR-V] Allow linking IR using llvm-link (PR #169572)

[Manuel Carrasco via cfe-commits]

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+// Check BC input
+// RUN: mkdir -p %t
+// RUN: touch %t/a.bc
+// RUN: touch %t/b.bc
+// RUN: %clang -### --target=spirv64 -emit-llvm %t/a.bc %t/b.bc 2>&1 | FileCheck --check-prefix=CHECK-TOOL-BC %s
+
+// CHECK-TOOL-BC: "-cc1" {{.*}} "-o" "[[TMP1_BC:.+]]" "-x" "ir" "{{.*}}.bc"
+// CHECK-TOOL-BC: "-cc1" {{.*}} "-o" "[[TMP2_BC:.+]]" "-x" "ir" "{{.*}}.bc"
+// CHECK-TOOL-BC: llvm-link{{.*}} "-o" {{.*}} "[[TMP1_BC]]" "[[TMP2_BC]]"
+
+// RUN: %clang -ccc-print-bindings --target=spirv64 -emit-llvm %t/a.bc %t/b.bc 2>&1 | FileCheck -check-prefix=CHECK-BINDINGS-BC %s
+
+// CHECK-BINDINGS-BC: "spirv64" - "clang", inputs: ["{{.*}}.bc"], output: "[[TMP1_BINDINGS_BC:.+]]"
+// CHECK-BINDINGS-BC: "spirv64" - "clang", inputs: ["{{.*}}.bc"], output: "[[TMP2_BINDINGS_BC:.+]]"
+// CHECK-BINDINGS-BC: "spirv64" - "SPIR-V::Linker", inputs: ["[[TMP1_BINDINGS_BC]]", "[[TMP2_BINDINGS_BC]]"], output: "{{.*}}.bc"
+
+// Check source input
+// RUN: touch %t/foo.c
+// RUN: touch %t/bar.c
+
+// RUN: %clang -### --target=spirv64 -emit-llvm %t/foo.c %t/bar.c 2>&1 | FileCheck --check-prefix=CHECK-TOOL-SRC %s
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mgcarrasco wrote:

Ty. So the expected behavior is that `-emit-llvm -S` does not do any linking, right?

https://github.com/llvm/llvm-project/pull/169572