[CUDA] Don't try to run sanitizers on NVPTX.

[jlebar]

Summary

Sanitizers aren't supported on NVPTX -- don't try to run them.

This lets you e.g. pass -fsanitize=address and get asan on your host
code.

[kcc]

LGTM

cfe/trunk/lib/Driver/SanitizerArgs.cpp

static void addIncludeLinkerOption(const ToolChain &TC,
   }
   LinkerOptionFlag += SymbolName;
   CmdArgs.push_back(Args.MakeArgString(LinkerOptionFlag));
 }
 
 void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
                             llvm::opt::ArgStringList &CmdArgs,
                             types::ID InputType) const {
+  // NVPTX doesn't currently support sanitizers.  Bailing out here means that
+  // e.g. -fsanitize=address applies only to host code, which is what we want
+  // for now.
+  if (TC.getTriple().isNVPTX())
+    return;
+
   // Translate available CoverageFeatures to corresponding clang-cc1 flags.
   // Do it even if Sanitizers.empty() since some forms of coverage don't require
   // sanitizers.
   std::pair<int, const char *> CoverageFlags[] = {
     std::make_pair(CoverageFunc, "-fsanitize-coverage-type=1"),
     std::make_pair(CoverageBB, "-fsanitize-coverage-type=2"),
     std::make_pair(CoverageEdge, "-fsanitize-coverage-type=3"),
     std::make_pair(CoverageIndirCall, "-fsanitize-coverage-indirect-calls"),

cfe/trunk/test/Driver/cuda-no-sanitizers.cu

+// Check that -fsanitize=foo doesn't get passed down to device-side
+// compilation.
+//
+// REQUIRES: clang-driver
+//
+// RUN: %clang -### -target x86_64-linux-gnu -c --cuda-gpu-arch=sm_20 -fsanitize=address %s 2>&1 | \
+// RUN:   FileCheck %s
+
+// CHECK-DAG: "-fcuda-is-device"
+// CHECK-NOT: "-fsanitize=address"
+// CHECK-DAG: "-triple" "x86_64--linux-gnu"
+// CHECK: "-fsanitize=address"