[CUDA] Add --ptxas-path= flag.

Summary:
This lets you build with one CUDA installation but use ptxas from
another install.

This is useful e.g. if you want to avoid bugs in an old ptxas without
actually upgrading wholesale to a newer CUDA version.

Reviewers: tra

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D27788

llvm-svn: 289847

1 files changed, 5 insertions, 1 deletions

diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index dbe8cfb340f..253a25695fe 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -12105,7 +12105,11 @@ void NVPTX::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
   for (const auto& A : Args.getAllArgValues(options::OPT_Xcuda_ptxas))
     CmdArgs.push_back(Args.MakeArgString(A));
 
-  const char *Exec = Args.MakeArgString(TC.GetProgramPath("ptxas"));
+  const char *Exec;
+  if (Arg *A = Args.getLastArg(options::OPT_ptxas_path_EQ))
+    Exec = A->getValue();
+  else
+    Exec = Args.MakeArgString(TC.GetProgramPath("ptxas"));
   C.addCommand(llvm::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
 }