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

[Manuel Carrasco via cfe-commits]

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@@ -33,32 +33,22 @@ using namespace llvm::opt;
 #define NULL_FILE "/dev/null"
 #endif
 
-void AMDGCN::Linker::constructLlvmLinkCommand(Compilation &C,
-                                         const JobAction &JA,
-                                         const InputInfoList &Inputs,
-                                         const InputInfo &Output,
-                                         const llvm::opt::ArgList &Args) const {
-  // Construct llvm-link command.
-  // The output from llvm-link is a bitcode file.
-  ArgStringList LlvmLinkArgs;
+void AMDGCN::Linker::constructLlvmLinkCommand(
+    Compilation &C, const JobAction &JA, const InputInfoList &Inputs,
+    const InputInfo &Output, const llvm::opt::ArgList &Args) const {
 
-  assert(!Inputs.empty() && "Must have at least one input.");
+  ArgStringList LinkerInputs;
 
-  LlvmLinkArgs.append({"-o", Output.getFilename()});
   for (auto Input : Inputs)
-    LlvmLinkArgs.push_back(Input.getFilename());
+    LinkerInputs.push_back(Input.getFilename());
 
   // Look for archive of bundled bitcode in arguments, and add temporary files
   // for the extracted archive of bitcode to inputs.
   auto TargetID = Args.getLastArgValue(options::OPT_mcpu_EQ);
-  AddStaticDeviceLibsLinking(C, *this, JA, Inputs, Args, LlvmLinkArgs, "amdgcn",
+  AddStaticDeviceLibsLinking(C, *this, JA, Inputs, Args, LinkerInputs, "amdgcn",
----------------
mgcarrasco wrote:

Before the changes, this function receives `LlvmLinkArgs` which contains `LlvmLinkArgs.append({"-o", Output.getFilename()});`. Now, it receives `LinkerInputs` which does not. Is this a sound change? Would it work as before?

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