diff --git a/lib/Target/PTX/PTX.h b/lib/Target/PTX/PTX.h
index 3db63a3..19385ba 100644
--- a/lib/Target/PTX/PTX.h
+++ b/lib/Target/PTX/PTX.h
@@ -21,6 +21,16 @@
   class PTXTargetMachine;
   class FunctionPass;
 
+  namespace PTX {
+    enum StateSpace {
+      GLOBAL = 0, // default to global state space
+      CONSTANT = 1,
+      LOCAL = 2,
+      PARAMETER = 3,
+      SHARED = 4
+    };
+  } // namespace PTX
+
   FunctionPass *createPTXISelDag(PTXTargetMachine &TM,
                                  CodeGenOpt::Level OptLevel);
 
diff --git a/lib/Target/PTX/PTXAsmPrinter.cpp b/lib/Target/PTX/PTXAsmPrinter.cpp
index cd27fb5..872287e 100644
--- a/lib/Target/PTX/PTXAsmPrinter.cpp
+++ b/lib/Target/PTX/PTXAsmPrinter.cpp
@@ -103,11 +103,14 @@
 }
 
 static const char *getStateSpaceName(unsigned addressSpace) {
-  if (addressSpace <= 255)
-    return "global";
-  // TODO Add more state spaces
-
-  llvm_unreachable("Unknown state space");
+  switch (addressSpace) {
+  default: llvm_unreachable("Unknown state space");
+  case PTX::GLOBAL:    return "global";
+  case PTX::CONSTANT:  return "const";
+  case PTX::LOCAL:     return "local";
+  case PTX::PARAMETER: return "param";
+  case PTX::SHARED:    return "shared";
+  }
   return NULL;
 }
 
diff --git a/lib/Target/PTX/PTXInstrInfo.td b/lib/Target/PTX/PTXInstrInfo.td
index 1072103..65386c8 100644
--- a/lib/Target/PTX/PTXInstrInfo.td
+++ b/lib/Target/PTX/PTXInstrInfo.td
@@ -22,9 +22,47 @@
 //===----------------------------------------------------------------------===//
 
 def load_global : PatFrag<(ops node:$ptr), (load node:$ptr), [{
-  if (const Value *Src = cast<LoadSDNode>(N)->getSrcValue())
-    if (const PointerType *PT = dyn_cast<PointerType>(Src->getType()))
-      return PT->getAddressSpace() <= 255;
+  const Value *Src;
+  const PointerType *PT;
+  if ((Src = cast<LoadSDNode>(N)->getSrcValue()) &&
+      (PT = dyn_cast<PointerType>(Src->getType())))
+    return PT->getAddressSpace() == PTX::GLOBAL;
+  return false;
+}]>;
+
+def load_constant : PatFrag<(ops node:$ptr), (load node:$ptr), [{
+  const Value *Src;
+  const PointerType *PT;
+  if ((Src = cast<LoadSDNode>(N)->getSrcValue()) &&
+      (PT = dyn_cast<PointerType>(Src->getType())))
+    return PT->getAddressSpace() == PTX::CONSTANT;
+  return false;
+}]>;
+
+def load_local : PatFrag<(ops node:$ptr), (load node:$ptr), [{
+  const Value *Src;
+  const PointerType *PT;
+  if ((Src = cast<LoadSDNode>(N)->getSrcValue()) &&
+      (PT = dyn_cast<PointerType>(Src->getType())))
+    return PT->getAddressSpace() == PTX::LOCAL;
+  return false;
+}]>;
+
+def load_parameter : PatFrag<(ops node:$ptr), (load node:$ptr), [{
+  const Value *Src;
+  const PointerType *PT;
+  if ((Src = cast<LoadSDNode>(N)->getSrcValue()) &&
+      (PT = dyn_cast<PointerType>(Src->getType())))
+    return PT->getAddressSpace() == PTX::PARAMETER;
+  return false;
+}]>;
+
+def load_shared : PatFrag<(ops node:$ptr), (load node:$ptr), [{
+  const Value *Src;
+  const PointerType *PT;
+  if ((Src = cast<LoadSDNode>(N)->getSrcValue()) &&
+      (PT = dyn_cast<PointerType>(Src->getType())))
+    return PT->getAddressSpace() == PTX::SHARED;
   return false;
 }]>;
 
@@ -142,6 +180,10 @@
 }
 
 defm LDg : PTX_LD<"ld.global", RRegs32, load_global>;
+defm LDc : PTX_LD<"ld.const",  RRegs32, load_constant>;
+defm LDl : PTX_LD<"ld.local",  RRegs32, load_local>;
+defm LDp : PTX_LD<"ld.param",  RRegs32, load_parameter>;
+defm LDs : PTX_LD<"ld.shared", RRegs32, load_shared>;
 
 ///===- Control Flow Instructions -----------------------------------------===//
 
diff --git a/test/CodeGen/PTX/ld.ll b/test/CodeGen/PTX/ld.ll
index 5ae82a0..baafbc2 100644
--- a/test/CodeGen/PTX/ld.ll
+++ b/test/CodeGen/PTX/ld.ll
@@ -3,6 +3,15 @@
 ;CHECK: .extern .global .s32 array[];
 @array = external global [10 x i32]
 
+;CHECK: .extern .const .s32 array_constant[];
+@array_constant = external addrspace(1) constant [10 x i32]
+
+;CHECK: .extern .local .s32 array_local[];
+@array_local = external addrspace(2) global [10 x i32]
+
+;CHECK: .extern .shared .s32 array_shared[];
+@array_shared = external addrspace(4) global [10 x i32]
+
 define ptx_device i32 @t1(i32* %p) {
 entry:
 ;CHECK: ld.global.s32 r0, [r1];
@@ -27,7 +36,7 @@
   ret i32 %x
 }
 
-define ptx_device i32 @t4() {
+define ptx_device i32 @t4_global() {
 entry:
 ;CHECK: ld.global.s32 r0, [array];
   %i = getelementptr [10 x i32]* @array, i32 0, i32 0
@@ -35,6 +44,30 @@
   ret i32 %x
 }
 
+define ptx_device i32 @t4_const() {
+entry:
+;CHECK: ld.const.s32 r0, [array_constant];
+  %i = getelementptr [10 x i32] addrspace(1)* @array_constant, i32 0, i32 0
+  %x = load i32 addrspace(1)* %i
+  ret i32 %x
+}
+
+define ptx_device i32 @t4_local() {
+entry:
+;CHECK: ld.local.s32 r0, [array_local];
+  %i = getelementptr [10 x i32] addrspace(2)* @array_local, i32 0, i32 0
+  %x = load i32 addrspace(2)* %i
+  ret i32 %x
+}
+
+define ptx_device i32 @t4_shared() {
+entry:
+;CHECK: ld.shared.s32 r0, [array_shared];
+  %i = getelementptr [10 x i32] addrspace(4)* @array_shared, i32 0, i32 0
+  %x = load i32 addrspace(4)* %i
+  ret i32 %x
+}
+
 define ptx_device i32 @t5() {
 entry:
 ;CHECK: ld.global.s32 r0, [array+4];