CPPBackend => JSBackend

22 files changed, 141 insertions, 134 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index fffdf9b87b..2918aeb86a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -78,6 +78,7 @@ set(LLVM_ALL_TARGETS
   ARM
   CppBackend
   Hexagon
+  JSBackend
   Mips
   MBlaze
   MSP430
diff --git a/configure b/configure
index 0116458ed5..fc3f040707 100755
--- a/configure
+++ b/configure
@@ -1445,7 +1445,7 @@ Optional Features:
   --enable-targets        Build specific host targets: all or
                           target1,target2,... Valid targets are: host, x86,
                           x86_64, sparc, powerpc, arm, aarch64, mips, hexagon,
-                          xcore, msp430, nvptx, systemz, and cpp (default=all)
+                          xcore, msp430, nvptx, systemz, js, and cpp (default=all)
   --enable-experimental-targets
                           Build experimental host targets: disable or
                           target1,target2,... (default=disable)
@@ -5641,7 +5641,7 @@ if test "$enableval" = host-only ; then
   enableval=host
 fi
 case "$enableval" in
-  all) TARGETS_TO_BUILD="X86 Sparc PowerPC AArch64 ARM Mips XCore MSP430 CppBackend MBlaze NVPTX Hexagon SystemZ" ;;
+  all) TARGETS_TO_BUILD="X86 Sparc PowerPC AArch64 ARM Mips XCore MSP430 CppBackend JSBackend MBlaze NVPTX Hexagon SystemZ" ;;
   *)for a_target in `echo $enableval|sed -e 's/,/ /g' ` ; do
       case "$a_target" in
         x86)      TARGETS_TO_BUILD="X86 $TARGETS_TO_BUILD" ;;
@@ -5657,6 +5657,7 @@ case "$enableval" in
         xcore)    TARGETS_TO_BUILD="XCore $TARGETS_TO_BUILD" ;;
         msp430)   TARGETS_TO_BUILD="MSP430 $TARGETS_TO_BUILD" ;;
         cpp)      TARGETS_TO_BUILD="CppBackend $TARGETS_TO_BUILD" ;;
+        js)       TARGETS_TO_BUILD="JSBackend $TARGETS_TO_BUILD" ;;
         hexagon)  TARGETS_TO_BUILD="Hexagon $TARGETS_TO_BUILD" ;;
         mblaze)   TARGETS_TO_BUILD="MBlaze $TARGETS_TO_BUILD" ;;
         nvptx)    TARGETS_TO_BUILD="NVPTX $TARGETS_TO_BUILD" ;;
diff --git a/lib/Target/CppBackend/CMakeLists.txt b/lib/Target/CppBackend/CMakeLists.txt
deleted file mode 100644
index 7e138b2695..0000000000
--- a/lib/Target/CppBackend/CMakeLists.txt
+++ /dev/null
@@ -1,6 +0,0 @@
-add_llvm_target(CppBackendCodeGen
-  CPPBackend.cpp
-  Relooper.cpp
-  )
-
-add_subdirectory(TargetInfo)
diff --git a/lib/Target/CppBackend/LLVMBuild.txt b/lib/Target/CppBackend/LLVMBuild.txt
index 122b5e7502..139597f9cb 100644
--- a/lib/Target/CppBackend/LLVMBuild.txt
+++ b/lib/Target/CppBackend/LLVMBuild.txt
@@ -1,31 +1,2 @@
-;===- ./lib/Target/CppBackend/LLVMBuild.txt --------------------*- Conf -*--===;
-;
-;                     The LLVM Compiler Infrastructure
-;
-; This file is distributed under the University of Illinois Open Source
-; License. See LICENSE.TXT for details.
-;
-;===------------------------------------------------------------------------===;
-;
-; This is an LLVMBuild description file for the components in this subdirectory.
-;
-; For more information on the LLVMBuild system, please see:
-;
-;   http://llvm.org/docs/LLVMBuild.html
-;
-;===------------------------------------------------------------------------===;
 
-[common]
-subdirectories = TargetInfo
 
-[component_0]
-type = TargetGroup
-name = CppBackend
-parent = Target
-
-[component_1]
-type = Library
-name = CppBackendCodeGen
-parent = CppBackend
-required_libraries = Core CppBackendInfo Support Target
-add_to_library_groups = CppBackend
diff --git a/lib/Target/CppBackend/TargetInfo/CppBackendTargetInfo.cpp b/lib/Target/CppBackend/TargetInfo/CppBackendTargetInfo.cpp
deleted file mode 100644
index 339b36105c..0000000000
--- a/lib/Target/CppBackend/TargetInfo/CppBackendTargetInfo.cpp
+++ /dev/null
@@ -1,28 +0,0 @@
-//===-- CppBackendTargetInfo.cpp - CppBackend Target Implementation -------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#include "CPPTargetMachine.h"
-#include "llvm/IR/Module.h"
-#include "llvm/Support/TargetRegistry.h"
-using namespace llvm;
-
-Target llvm::TheCppBackendTarget;
-
-static unsigned CppBackend_TripleMatchQuality(const std::string &TT) {
-  // This class always works, but shouldn't be the default in most cases.
-  return 1;
-}
-
-extern "C" void LLVMInitializeCppBackendTargetInfo() { 
-  TargetRegistry::RegisterTarget(TheCppBackendTarget, "js",
-                                  "JavaScript backend",
-                                  &CppBackend_TripleMatchQuality);
-}
-
-extern "C" void LLVMInitializeCppBackendTargetMC() {}
diff --git a/lib/Target/CppBackend/readme.txt b/lib/Target/CppBackend/readme.txt
new file mode 100644
index 0000000000..aa482b2fd4
--- /dev/null
+++ b/lib/Target/CppBackend/readme.txt
@@ -0,0 +1 @@
+TODO: restore old cpp backend to here
diff --git a/lib/Target/JSBackend/CMakeLists.txt b/lib/Target/JSBackend/CMakeLists.txt
new file mode 100644
index 0000000000..9d38665eeb
--- /dev/null
+++ b/lib/Target/JSBackend/CMakeLists.txt
@@ -0,0 +1,6 @@
+add_llvm_target(JSBackendCodeGen
+  JSBackend.cpp
+  Relooper.cpp
+  )
+
+add_subdirectory(TargetInfo)
diff --git a/lib/Target/CppBackend/CallHandlers.h b/lib/Target/JSBackend/CallHandlers.h
index d23fa7e9b9..0bd7e191cb 100644
--- a/lib/Target/CppBackend/CallHandlers.h
+++ b/lib/Target/JSBackend/CallHandlers.h
@@ -37,13 +37,13 @@ DEF_CALL_HANDLER(__default__, {
   text += ")";
   Type *RT = CI->getType();
   if (!RT->isVoidTy()) {
-    text = getAssign(getCppName(CI), RT) + getCast(text, RT, ASM_NONSPECIFIC);
+    text = getAssign(getJSName(CI), RT) + getCast(text, RT, ASM_NONSPECIFIC);
   }
   return text;
 })
 
 DEF_CALL_HANDLER(getHigh32, {
-  return getAssign(getCppName(CI), CI->getType()) + "tempRet0";
+  return getAssign(getJSName(CI), CI->getType()) + "tempRet0";
 })
 
 DEF_CALL_HANDLER(setHigh32, {
@@ -51,48 +51,48 @@ DEF_CALL_HANDLER(setHigh32, {
 })
 
 DEF_CALL_HANDLER(FPtoILow, {
-  return getAssign(getCppName(CI), CI->getType()) + "(~~" + getValueAsStr(CI->getArgOperand(0)) + ")>>>0";
+  return getAssign(getJSName(CI), CI->getType()) + "(~~" + getValueAsStr(CI->getArgOperand(0)) + ")>>>0";
 })
 
 DEF_CALL_HANDLER(FPtoIHigh, {
   std::string Input = getValueAsStr(CI->getArgOperand(0));
-  return getAssign(getCppName(CI), CI->getType()) + "+Math_abs(" + Input + ") >= +1 ? " + Input + " > +0 ? (Math_min(+Math_floor(" + Input + " / +4294967296), +4294967295) | 0) >>> 0 : ~~+Math_ceil((" + Input + " - +(~~" + Input + " >>> 0)) / +4294967296) >>> 0 : 0";
+  return getAssign(getJSName(CI), CI->getType()) + "+Math_abs(" + Input + ") >= +1 ? " + Input + " > +0 ? (Math_min(+Math_floor(" + Input + " / +4294967296), +4294967295) | 0) >>> 0 : ~~+Math_ceil((" + Input + " - +(~~" + Input + " >>> 0)) / +4294967296) >>> 0 : 0";
 })
 
 DEF_CALL_HANDLER(BDtoILow, {
-  return "HEAPF64[tempDoublePtr>>3] = " + getValueAsStr(CI->getArgOperand(0)) + ";" + getAssign(getCppName(CI), CI->getType()) + "HEAP32[tempDoublePtr>>2]|0";
+  return "HEAPF64[tempDoublePtr>>3] = " + getValueAsStr(CI->getArgOperand(0)) + ";" + getAssign(getJSName(CI), CI->getType()) + "HEAP32[tempDoublePtr>>2]|0";
 })
 
 DEF_CALL_HANDLER(BDtoIHigh, {
-  return getAssign(getCppName(CI), CI->getType()) + "HEAP32[tempDoublePtr+4>>2]|0";
+  return getAssign(getJSName(CI), CI->getType()) + "HEAP32[tempDoublePtr+4>>2]|0";
 })
 
 DEF_CALL_HANDLER(SItoF, {
   // TODO: fround
-  return getAssign(getCppName(CI), CI->getType()) + "(+" + getValueAsCastParenStr(CI->getArgOperand(0), ASM_UNSIGNED) + ") + " +
+  return getAssign(getJSName(CI), CI->getType()) + "(+" + getValueAsCastParenStr(CI->getArgOperand(0), ASM_UNSIGNED) + ") + " +
                                        "(+4294967296*(+" + getValueAsCastParenStr(CI->getArgOperand(1), ASM_SIGNED) +   "))";
 })
 
 DEF_CALL_HANDLER(UItoF, {
   // TODO: fround
-  return getAssign(getCppName(CI), CI->getType()) + "(+" + getValueAsCastParenStr(CI->getArgOperand(0), ASM_UNSIGNED) + ") + " +
+  return getAssign(getJSName(CI), CI->getType()) + "(+" + getValueAsCastParenStr(CI->getArgOperand(0), ASM_UNSIGNED) + ") + " +
                                        "(+4294967296*(+" + getValueAsCastParenStr(CI->getArgOperand(1), ASM_UNSIGNED) + "))";
 })
 
 DEF_CALL_HANDLER(SItoD, {
-  return getAssign(getCppName(CI), CI->getType()) + "(+" + getValueAsCastParenStr(CI->getArgOperand(0), ASM_UNSIGNED) + ") + " +
+  return getAssign(getJSName(CI), CI->getType()) + "(+" + getValueAsCastParenStr(CI->getArgOperand(0), ASM_UNSIGNED) + ") + " +
                                        "(+4294967296*(+" + getValueAsCastParenStr(CI->getArgOperand(1), ASM_SIGNED) +   "))";
 })
 
 DEF_CALL_HANDLER(UItoD, {
-  return getAssign(getCppName(CI), CI->getType()) + "(+" + getValueAsCastParenStr(CI->getArgOperand(0), ASM_UNSIGNED) + ") + " +
+  return getAssign(getJSName(CI), CI->getType()) + "(+" + getValueAsCastParenStr(CI->getArgOperand(0), ASM_UNSIGNED) + ") + " +
                                        "(+4294967296*(+" + getValueAsCastParenStr(CI->getArgOperand(1), ASM_UNSIGNED) + "))";
 })
 
 DEF_CALL_HANDLER(BItoD, {
   return "HEAP32[tempDoublePtr>>2] = " +   getValueAsStr(CI->getArgOperand(0)) + ";" +
          "HEAP32[tempDoublePtr+4>>2] = " + getValueAsStr(CI->getArgOperand(1)) + ";" +
-         getAssign(getCppName(CI), CI->getType()) + "+HEAPF64[tempDoublePtr>>3]";
+         getAssign(getJSName(CI), CI->getType()) + "+HEAPF64[tempDoublePtr>>3]";
 })
 
 DEF_CALL_HANDLER(llvm_nacl_atomic_store_i32, {
@@ -115,7 +115,7 @@ DEF_CALL_HANDLER(llvm_memmove_p0i8_p0i8_i32, {
 })
 
 DEF_CALL_HANDLER(llvm_expect_i32, {
-  return getAssign(getCppName(CI), CI->getType()) + getValueAsStr(CI->getArgOperand(0));
+  return getAssign(getJSName(CI), CI->getType()) + getValueAsStr(CI->getArgOperand(0));
 })
 
 DEF_CALL_HANDLER(llvm_dbg_declare, {
@@ -713,7 +713,7 @@ void setupCallHandlers() {
 std::string handleCall(const CallInst *CI) {
   const Value *CV = CI->getCalledValue();
   assert(!isa<InlineAsm>(CV) && "asm() not supported, use EM_ASM() (see emscripten.h)");
-  std::string Name = getCppName(CV);
+  std::string Name = getJSName(CV);
   if (strcmp(Name.c_str(), "_llvm_dbg_value") == 0) return ""; // ignore this
   unsigned NumArgs = CI->getNumArgOperands();
   CallHandlerMap::iterator CH = CallHandlers->find("___default__");
diff --git a/lib/Target/CppBackend/CPPBackend.cpp b/lib/Target/JSBackend/JSBackend.cpp
index 1253d8a622..656e40753f 100644
--- a/lib/Target/CppBackend/CPPBackend.cpp
+++ b/lib/Target/JSBackend/JSBackend.cpp
@@ -1,4 +1,4 @@
-//===-- CPPBackend.cpp - Library for converting LLVM code to JS       -----===//
+//===-- JSBackend.cpp - Library for converting LLVM code to JS       -----===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -14,7 +14,7 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "CPPTargetMachine.h"
+#include "JSTargetMachine.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Config/config.h"
@@ -57,9 +57,9 @@ using namespace llvm;
 #undef assert
 #define assert(x) { if (!(x)) dumpfail(#x); }
 
-extern "C" void LLVMInitializeCppBackendTarget() {
+extern "C" void LLVMInitializeJSBackendTarget() {
   // Register the target.
-  RegisterTargetMachine<CPPTargetMachine> X(TheCppBackendTarget);
+  RegisterTargetMachine<JSTargetMachine> X(TheJSBackendTarget);
 }
 
 namespace {
@@ -191,7 +191,7 @@ namespace {
       return Ret;
     }
     unsigned getFunctionIndex(const Function *F) {
-      std::string Name = getCppName(F);
+      std::string Name = getJSName(F);
       if (IndexedFunctions.find(Name) != IndexedFunctions.end()) return IndexedFunctions[Name];
       std::string Sig = getFunctionSignature(F->getFunctionType());
       FunctionTable &Table = FunctionTables[Sig];
@@ -258,7 +258,7 @@ namespace {
     std::string getValueAsParenStr(const Value*);
     std::string getValueAsCastParenStr(const Value*, AsmCast sign=ASM_SIGNED);
 
-    std::string getCppName(const Value* val);
+    std::string getJSName(const Value* val);
 
     std::string getPhiCode(const BasicBlock *From, const BasicBlock *To);
 
@@ -328,7 +328,7 @@ std::string JSWriter::getPhiCode(const BasicBlock *From, const BasicBlock *To) {
     int index = P->getBasicBlockIndex(From);
     if (index < 0) continue;
     // we found it
-    std::string name = getCppName(P);
+    std::string name = getJSName(P);
     assigns[name] = getAssign(name, P->getType());
     Value *V = P->getIncomingValue(index);
     values[name] = V;
@@ -371,7 +371,7 @@ std::string JSWriter::getPhiCode(const BasicBlock *From, const BasicBlock *To) {
   return pre + post;
 }
 
-std::string JSWriter::getCppName(const Value* val) {
+std::string JSWriter::getJSName(const Value* val) {
   std::string name;
   ValueMap::iterator I = ValueNames.find(val);
   if (I != ValueNames.end() && I->first == val)
@@ -626,7 +626,7 @@ std::string JSWriter::getStore(const Value *P, const Type *T, const std::string&
 }
 
 std::string JSWriter::getOpName(const Value* V) { // TODO: remove this
-  return getCppName(V);
+  return getJSName(V);
 }
 
 std::string JSWriter::getPtrLoad(const Value* Ptr) {
@@ -744,7 +744,7 @@ std::string JSWriter::getValueAsStr(const Value* V, AsmCast sign) {
   if (const Constant *CV = dyn_cast<Constant>(V)) {
     return getConstant(CV, sign);
   } else {
-    return getCppName(V);
+    return getJSName(V);
   }
 }
 
@@ -752,7 +752,7 @@ std::string JSWriter::getValueAsCastStr(const Value* V, AsmCast sign) {
   if (const Constant *CV = dyn_cast<Constant>(V)) {
     return getConstant(CV, sign);
   } else {
-    return getCast(getCppName(V), V->getType(), sign);
+    return getCast(getJSName(V), V->getType(), sign);
   }
 }
 
@@ -760,7 +760,7 @@ std::string JSWriter::getValueAsParenStr(const Value* V) {
   if (const Constant *CV = dyn_cast<Constant>(V)) {
     return getConstant(CV);
   } else {
-    return "(" + getCppName(V) + ")";
+    return "(" + getJSName(V) + ")";
   }
 }
 
@@ -768,13 +768,13 @@ std::string JSWriter::getValueAsCastParenStr(const Value* V, AsmCast sign) {
   if (const Constant *CV = dyn_cast<Constant>(V)) {
     return getConstant(CV, sign);
   } else {
-    return "(" + getCast(getCppName(V), V->getType(), sign) + ")";
+    return "(" + getCast(getJSName(V), V->getType(), sign) + ")";
   }
 }
 
 // generateInstruction - This member is called for each Instruction in a function.
 void JSWriter::generateInstruction(const Instruction *I, raw_string_ostream& Code) {
-  std::string iName(getCppName(I));
+  std::string iName(getJSName(I));
 
   Type *T = I->getType();
   if (T->isIntegerTy() && T->getIntegerBitWidth() > 32) {
@@ -1329,13 +1329,13 @@ void JSWriter::printModuleBody() {
       for (Function::const_arg_iterator AI = I->arg_begin(), AE = I->arg_end();
            AI != AE; ++AI) {
         if (AI != I->arg_begin()) Out << ",";
-        Out << getCppName(AI);
+        Out << getJSName(AI);
       }
       Out << ") {";
       nl(Out);
       for (Function::const_arg_iterator AI = I->arg_begin(), AE = I->arg_end();
            AI != AE; ++AI) {
-        std::string name = getCppName(AI);
+        std::string name = getJSName(AI);
         Out << " " << name << " = " << getCast(name, AI->getType(), ASM_NONSPECIFIC) << ";";
         nl(Out);
       }
@@ -1545,7 +1545,7 @@ void JSWriter::parseConstant(const std::string& name, const Constant* CV, bool c
           if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
             C = CE->getOperand(0); // ignore bitcasts
           }
-          GlobalInitializers.push_back(getCppName(C));
+          GlobalInitializers.push_back(getJSName(C));
         }
       }
     } else if (calculate) {
@@ -1612,7 +1612,7 @@ void JSWriter::parseConstant(const std::string& name, const Constant* CV, bool c
       // this is the global static initializer
       if (calculate) {
         Value *V = CE->getOperand(0);
-        GlobalInitializers.push_back(getCppName(V));
+        GlobalInitializers.push_back(getJSName(V));
         // is the func
       }
     } else if (name == "__fini_array_start") {
@@ -1722,12 +1722,12 @@ char JSWriter::ID = 0;
 //                       External Interface declaration
 //===----------------------------------------------------------------------===//
 
-bool CPPTargetMachine::addPassesToEmitFile(PassManagerBase &PM,
-                                           formatted_raw_ostream &o,
-                                           CodeGenFileType FileType,
-                                           bool DisableVerify,
-                                           AnalysisID StartAfter,
-                                           AnalysisID StopAfter) {
+bool JSTargetMachine::addPassesToEmitFile(PassManagerBase &PM,
+                                          formatted_raw_ostream &o,
+                                          CodeGenFileType FileType,
+                                          bool DisableVerify,
+                                          AnalysisID StartAfter,
+                                          AnalysisID StopAfter) {
   assert(FileType == TargetMachine::CGFT_AssemblyFile);
 
   PM.add(createSimplifyAllocasPass());
diff --git a/lib/Target/CppBackend/CPPTargetMachine.h b/lib/Target/JSBackend/JSTargetMachine.h
index 477e788ee2..b11533d692 100644
--- a/lib/Target/CppBackend/CPPTargetMachine.h
+++ b/lib/Target/JSBackend/JSTargetMachine.h
@@ -1,18 +1,19 @@
-//===-- CPPTargetMachine.h - TargetMachine for the C++ backend --*- C++ -*-===//
+//===-- JSTargetMachine.h - TargetMachine for the C++ backend --*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
-//===----------------------------------------------------------------------===//
+//===---------------------------------------------------------------------===//
 //
-// This file declares the TargetMachine that is used by the C++ backend.
+// This file declares the TargetMachine that is used by the JS/asm.js/
+// emscripten backend.
 //
-//===----------------------------------------------------------------------===//
+//===---------------------------------------------------------------------===//
 
-#ifndef CPPTARGETMACHINE_H
-#define CPPTARGETMACHINE_H
+#ifndef JSTARGETMACHINE_H
+#define JSTARGETMACHINE_H
 
 #include "llvm/IR/DataLayout.h"
 #include "llvm/Target/TargetMachine.h"
@@ -21,11 +22,11 @@ namespace llvm {
 
 class formatted_raw_ostream;
 
-struct CPPTargetMachine : public TargetMachine {
-  CPPTargetMachine(const Target &T, StringRef TT,
-                   StringRef CPU, StringRef FS, const TargetOptions &Options,
-                   Reloc::Model RM, CodeModel::Model CM,
-                   CodeGenOpt::Level OL)
+struct JSTargetMachine : public TargetMachine {
+  JSTargetMachine(const Target &T, StringRef TT,
+                  StringRef CPU, StringRef FS, const TargetOptions &Options,
+                  Reloc::Model RM, CodeModel::Model CM,
+                  CodeGenOpt::Level OL)
     : TargetMachine(T, TT, CPU, FS, Options) {}
 
   virtual bool addPassesToEmitFile(PassManagerBase &PM,
@@ -38,7 +39,7 @@ struct CPPTargetMachine : public TargetMachine {
   virtual const DataLayout *getDataLayout() const { return 0; }
 };
 
-extern Target TheCppBackendTarget;
+extern Target TheJSBackendTarget;
 
 } // End llvm namespace
 
diff --git a/lib/Target/JSBackend/LLVMBuild.txt b/lib/Target/JSBackend/LLVMBuild.txt
new file mode 100644
index 0000000000..33b433bfb7
--- /dev/null
+++ b/lib/Target/JSBackend/LLVMBuild.txt
@@ -0,0 +1,31 @@
+;===- ./lib/Target/JSBackend/LLVMBuild.txt --------------------*- Conf -*--===;
+;
+;                     The LLVM Compiler Infrastructure
+;
+; This file is distributed under the University of Illinois Open Source
+; License. See LICENSE.TXT for details.
+;
+;===------------------------------------------------------------------------===;
+;
+; This is an LLVMBuild description file for the components in this subdirectory.
+;
+; For more information on the LLVMBuild system, please see:
+;
+;   http://llvm.org/docs/LLVMBuild.html
+;
+;===------------------------------------------------------------------------===;
+
+[common]
+subdirectories = TargetInfo
+
+[component_0]
+type = TargetGroup
+name = JSBackend
+parent = Target
+
+[component_1]
+type = Library
+name = JSBackendCodeGen
+parent = JSBackend
+required_libraries = Core JSBackendInfo Support Target
+add_to_library_groups = JSBackend
diff --git a/lib/Target/CppBackend/Makefile b/lib/Target/JSBackend/Makefile
index efc7463fda..8a15e7f4c1 100644
--- a/lib/Target/CppBackend/Makefile
+++ b/lib/Target/JSBackend/Makefile
@@ -1,14 +1,14 @@
-##===- lib/Target/CppBackend/Makefile --- ------------------*- Makefile -*-===##
+##===- lib/Target/JSBackend/Makefile --- ------------------*- Makefile -*-===##
 #
 #                     The LLVM Compiler Infrastructure
 #
 # This file is distributed under the University of Illinois Open Source
 # License. See LICENSE.TXT for details.
 #
-##===----------------------------------------------------------------------===##
+##===---------------------------------------------------------------------===##
 
 LEVEL = ../../..
-LIBRARYNAME = LLVMCppBackendCodeGen
+LIBRARYNAME = LLVMJSBackendCodeGen
 DIRS = TargetInfo
 
 include $(LEVEL)/Makefile.common
diff --git a/lib/Target/CppBackend/OptPasses.h b/lib/Target/JSBackend/OptPasses.h
index 99f1459462..d976ad226d 100644
--- a/lib/Target/CppBackend/OptPasses.h
+++ b/lib/Target/JSBackend/OptPasses.h
@@ -1,11 +1,11 @@
-//===-- CPPTargetMachine.h - TargetMachine for the C++ backend --*- C++ -*-===//
+//===-- JSTargetMachine.h - TargetMachine for the C++ backend --*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
-//===----------------------------------------------------------------------===//
+//===---------------------------------------------------------------------===//
 
 #ifndef OPT_PASSES_H
 #define OPT_PASSES_H
diff --git a/lib/Target/CppBackend/Relooper.cpp b/lib/Target/JSBackend/Relooper.cpp
index fc7b3ea777..fc7b3ea777 100644
--- a/lib/Target/CppBackend/Relooper.cpp
+++ b/lib/Target/JSBackend/Relooper.cpp
diff --git a/lib/Target/CppBackend/Relooper.h b/lib/Target/JSBackend/Relooper.h
index e78d18e713..e78d18e713 100644
--- a/lib/Target/CppBackend/Relooper.h
+++ b/lib/Target/JSBackend/Relooper.h
diff --git a/lib/Target/CppBackend/SimplifyAllocas.cpp b/lib/Target/JSBackend/SimplifyAllocas.cpp
index 1d4823ec57..2fda6be948 100644
--- a/lib/Target/CppBackend/SimplifyAllocas.cpp
+++ b/lib/Target/JSBackend/SimplifyAllocas.cpp
@@ -1,11 +1,11 @@
-//===-- CPPTargetMachine.h - TargetMachine for the C++ backend --*- C++ -*-===//
+//===-- SimplifyAllocas.cpp - TargetMachine for the C++ backend --*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
-//===----------------------------------------------------------------------===//
+//===-----------------------------------------------------------------------===//
 
 #include <OptPasses.h>
 
diff --git a/lib/Target/CppBackend/TargetInfo/CMakeLists.txt b/lib/Target/JSBackend/TargetInfo/CMakeLists.txt
index f82d72e378..29994eb8f9 100644
--- a/lib/Target/CppBackend/TargetInfo/CMakeLists.txt
+++ b/lib/Target/JSBackend/TargetInfo/CMakeLists.txt
@@ -1,5 +1,5 @@
 include_directories( ${CMAKE_CURRENT_BINARY_DIR}/.. ${CMAKE_CURRENT_SOURCE_DIR}/.. )
 
-add_llvm_library(LLVMCppBackendInfo
-  CppBackendTargetInfo.cpp
+add_llvm_library(LLVMJSBackendInfo
+  JSBackendTargetInfo.cpp
   )
diff --git a/lib/Target/JSBackend/TargetInfo/CppBackendTargetInfo.cpp b/lib/Target/JSBackend/TargetInfo/CppBackendTargetInfo.cpp
new file mode 100644
index 0000000000..cf06eaceea
--- /dev/null
+++ b/lib/Target/JSBackend/TargetInfo/CppBackendTargetInfo.cpp
@@ -0,0 +1,28 @@
+//===-- JSBackendTargetInfo.cpp - JSBackend Target Implementation -------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===--------------------------------------------------------------------===//
+
+#include "JSTargetMachine.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/TargetRegistry.h"
+using namespace llvm;
+
+Target llvm::TheJSBackendTarget;
+
+static unsigned JSBackend_TripleMatchQuality(const std::string &TT) {
+  // This class always works, but shouldn't be the default in most cases.
+  return 1;
+}
+
+extern "C" void LLVMInitializeJSBackendTargetInfo() { 
+  TargetRegistry::RegisterTarget(TheJSBackendTarget, "js",
+                                 "JavaScript (asm.js, emscripten) backend",
+                                 &JSBackend_TripleMatchQuality);
+}
+
+extern "C" void LLVMInitializeJSBackendTargetMC() {}
diff --git a/lib/Target/CppBackend/TargetInfo/LLVMBuild.txt b/lib/Target/JSBackend/TargetInfo/LLVMBuild.txt
index d4dfc3ef04..7320582609 100644
--- a/lib/Target/CppBackend/TargetInfo/LLVMBuild.txt
+++ b/lib/Target/JSBackend/TargetInfo/LLVMBuild.txt
@@ -1,11 +1,11 @@
-;===- ./lib/Target/CppBackend/TargetInfo/LLVMBuild.txt ---------*- Conf -*--===;
+;===- ./lib/Target/JSBackend/TargetInfo/LLVMBuild.txt ---------*- Conf -*--===;
 ;
 ;                     The LLVM Compiler Infrastructure
 ;
 ; This file is distributed under the University of Illinois Open Source
 ; License. See LICENSE.TXT for details.
 ;
-;===------------------------------------------------------------------------===;
+;===-----------------------------------------------------------------------===;
 ;
 ; This is an LLVMBuild description file for the components in this subdirectory.
 ;
@@ -13,11 +13,11 @@
 ;
 ;   http://llvm.org/docs/LLVMBuild.html
 ;
-;===------------------------------------------------------------------------===;
+;===-----------------------------------------------------------------------===;
 
 [component_0]
 type = Library
-name = CppBackendInfo
-parent = CppBackend
+name = JSBackendInfo
+parent = JSBackend
 required_libraries = MC Support Target
-add_to_library_groups = CppBackend
+add_to_library_groups = JSBackend
diff --git a/lib/Target/CppBackend/TargetInfo/Makefile b/lib/Target/JSBackend/TargetInfo/Makefile
index 6e682838da..45f0230efc 100644
--- a/lib/Target/CppBackend/TargetInfo/Makefile
+++ b/lib/Target/JSBackend/TargetInfo/Makefile
@@ -1,13 +1,13 @@
-##===- lib/Target/CppBackend/TargetInfo/Makefile -----------*- Makefile -*-===##
+##===- lib/Target/JSBackend/TargetInfo/Makefile -----------*- Makefile -*-===##
 #
 #                     The LLVM Compiler Infrastructure
 #
 # This file is distributed under the University of Illinois Open Source
 # License. See LICENSE.TXT for details.
 #
-##===----------------------------------------------------------------------===##
+##===---------------------------------------------------------------------===##
 LEVEL = ../../../..
-LIBRARYNAME = LLVMCppBackendInfo
+LIBRARYNAME = LLVMJSBackendInfo
 
 # Hack: we need to include 'main' target directory to grab private headers
 CPPFLAGS = -I$(PROJ_OBJ_DIR)/.. -I$(PROJ_SRC_DIR)/..
diff --git a/lib/Target/LLVMBuild.txt b/lib/Target/LLVMBuild.txt
index 1022ae9088..407d8116d3 100644
--- a/lib/Target/LLVMBuild.txt
+++ b/lib/Target/LLVMBuild.txt
@@ -16,7 +16,7 @@
 ;===------------------------------------------------------------------------===;
 
 [common]
-subdirectories = AArch64 ARM CppBackend Hexagon MBlaze MSP430 NVPTX Mips PowerPC R600 Sparc SystemZ X86 XCore
+subdirectories = AArch64 ARM CppBackend Hexagon JSBackend MBlaze MSP430 NVPTX Mips PowerPC R600 Sparc SystemZ X86 XCore
 
 ; This is a special group whose required libraries are extended (by llvm-build)
 ; with the best execution engine (the native JIT, if available, or the
diff --git a/projects/sample/configure b/projects/sample/configure
index 8484a2ae3c..ed66e1c00b 100755
--- a/projects/sample/configure
+++ b/projects/sample/configure
@@ -5308,7 +5308,7 @@ if test "$enableval" = host-only ; then
   enableval=host
 fi
 case "$enableval" in
-  all) TARGETS_TO_BUILD="X86 Sparc PowerPC ARM AArch64 Mips XCore MSP430 Hexagon CppBackend MBlaze NVPTX SystemZ" ;;
+  all) TARGETS_TO_BUILD="X86 Sparc PowerPC ARM AArch64 Mips XCore MSP430 Hexagon CppBackend JSBackend MBlaze NVPTX SystemZ" ;;
   *)for a_target in `echo $enableval|sed -e 's/,/ /g' ` ; do
       case "$a_target" in
         x86)      TARGETS_TO_BUILD="X86 $TARGETS_TO_BUILD" ;;
@@ -5322,6 +5322,7 @@ case "$enableval" in
         msp430)   TARGETS_TO_BUILD="MSP430 $TARGETS_TO_BUILD" ;;
         hexagon)  TARGETS_TO_BUILD="Hexagon $TARGETS_TO_BUILD" ;;
         cpp)      TARGETS_TO_BUILD="CppBackend $TARGETS_TO_BUILD" ;;
+        js)       TARGETS_TO_BUILD="JSBackend $TARGETS_TO_BUILD" ;;
         mblaze)   TARGETS_TO_BUILD="MBlaze $TARGETS_TO_BUILD" ;;
         nvptx)    TARGETS_TO_BUILD="NVPTX $TARGETS_TO_BUILD" ;;
         systemz)  TARGETS_TO_BUILD="SystemZ $TARGETS_TO_BUILD" ;;