[WebAssembly] Initial linking support.

This begins minimal support for invoking 'ld' from clang for WebAssembly
targets.

Differential Revision: http://reviews.llvm.org/D15586

llvm-svn: 255848

1 files changed, 13 insertions, 0 deletions

diff --git a/clang/lib/Driver/ToolChains.cpp b/clang/lib/Driver/ToolChains.cpp
index 0921bc19947..4cf4ca0ca34 100644
--- a/clang/lib/Driver/ToolChains.cpp
+++ b/clang/lib/Driver/ToolChains.cpp
@@ -4418,6 +4418,13 @@ Tool *MyriadToolChain::buildLinker() const {
   return new tools::Myriad::Linker(*this);
 }
 
+WebAssembly::WebAssembly(const Driver &D, const llvm::Triple &Triple,
+                         const llvm::opt::ArgList &Args)
+  : ToolChain(D, Triple, Args) {
+  // Use LLD by default.
+  DefaultLinker = "lld";
+}
+
 bool WebAssembly::IsMathErrnoDefault() const { return false; }
 
 bool WebAssembly::IsObjCNonFragileABIDefault() const { return true; }
@@ -4440,6 +4447,8 @@ bool WebAssembly::hasBlocksRuntime() const { return false; }
 // TODO: Support profiling.
 bool WebAssembly::SupportsProfiling() const { return false; }
 
+bool WebAssembly::HasNativeLLVMSupport() const { return true; }
+
 void WebAssembly::addClangTargetOptions(const ArgList &DriverArgs,
                                         ArgStringList &CC1Args) const {
   if (DriverArgs.hasFlag(options::OPT_fuse_init_array,
@@ -4447,6 +4456,10 @@ void WebAssembly::addClangTargetOptions(const ArgList &DriverArgs,
     CC1Args.push_back("-fuse-init-array");
 }
 
+Tool *WebAssembly::buildLinker() const {
+  return new tools::wasm::Linker(*this);
+}
+
 PS4CPU::PS4CPU(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
     : Generic_ELF(D, Triple, Args) {
   if (Args.hasArg(options::OPT_static))