Index: llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp
===================================================================
--- llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp
+++ llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp
@@ -1354,7 +1354,6 @@
                      const OperandInfoTy &Offset,
                      const OperandInfoTy &Width);
 
-  OperandMatchResultTy parseExpTgtImpl(StringRef Str, uint8_t &Val);
   SMLoc getFlatOffsetLoc(const OperandVector &Operands) const;
   SMLoc getSMEMOffsetLoc(const OperandVector &Operands) const;
 
@@ -5879,76 +5878,24 @@
 // exp
 //===----------------------------------------------------------------------===//
 
-OperandMatchResultTy AMDGPUAsmParser::parseExpTgtImpl(StringRef Str,
-                                                      uint8_t &Val) {
-  if (Str == "null") {
-    Val = Exp::ET_NULL;
-    return MatchOperand_Success;
-  }
-
-  if (Str.startswith("mrt")) {
-    Str = Str.drop_front(3);
-    if (Str == "z") { // == mrtz
-      Val = Exp::ET_MRTZ;
-      return MatchOperand_Success;
-    }
-
-    if (Str.getAsInteger(10, Val))
-      return MatchOperand_ParseFail;
-
-    if (Val > Exp::ET_MRT7)
-      return MatchOperand_ParseFail;
-
-    return MatchOperand_Success;
-  }
-
-  if (Str.startswith("pos")) {
-    Str = Str.drop_front(3);
-    if (Str.getAsInteger(10, Val))
-      return MatchOperand_ParseFail;
-
-    if (Val > (isGFX10Plus() ? 4 : 3))
-      return MatchOperand_ParseFail;
-
-    Val += Exp::ET_POS0;
-    return MatchOperand_Success;
-  }
-
-  if (isGFX10Plus() && Str == "prim") {
-    Val = Exp::ET_PRIM;
-    return MatchOperand_Success;
-  }
-
-  if (Str.startswith("param")) {
-    Str = Str.drop_front(5);
-    if (Str.getAsInteger(10, Val))
-      return MatchOperand_ParseFail;
-
-    if (Val >= 32)
-      return MatchOperand_ParseFail;
-
-    Val += Exp::ET_PARAM0;
-    return MatchOperand_Success;
-  }
-
-  return MatchOperand_ParseFail;
-}
-
 OperandMatchResultTy AMDGPUAsmParser::parseExpTgt(OperandVector &Operands) {
+  using namespace llvm::AMDGPU::Exp;
+
   StringRef Str;
   SMLoc S = getLoc();
 
   if (!parseId(Str))
     return MatchOperand_NoMatch;
 
-  uint8_t Val;
-  auto Res = parseExpTgtImpl(Str, Val);
-  if (Res != MatchOperand_Success) {
-    Error(S, "invalid exp target");
-    return Res;
+  unsigned Id = getTgtId(Str);
+  if (Id == ET_INVALID || !isSupportedTgtId(Id, getSTI())) {
+    Error(S, (Id == ET_INVALID) ?
+                "invalid exp target" :
+                "exp target is not supported on this GPU");
+    return MatchOperand_ParseFail;
   }
 
-  Operands.push_back(AMDGPUOperand::CreateImm(this, Val, S,
+  Operands.push_back(AMDGPUOperand::CreateImm(this, Id, S,
                                               AMDGPUOperand::ImmTyExpTgt));
   return MatchOperand_Success;
 }
Index: llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUInstPrinter.cpp
===================================================================
--- llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUInstPrinter.cpp
+++ llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUInstPrinter.cpp
@@ -1004,25 +1004,19 @@
 void AMDGPUInstPrinter::printExpTgt(const MCInst *MI, unsigned OpNo,
                                     const MCSubtargetInfo &STI,
                                     raw_ostream &O) {
+  using namespace llvm::AMDGPU::Exp;
+
   // This is really a 6 bit field.
-  uint32_t Tgt = MI->getOperand(OpNo).getImm() & ((1 << 6) - 1);
-
-  if (Tgt <= Exp::ET_MRT7)
-    O << " mrt" << Tgt - Exp::ET_MRT0;
-  else if (Tgt == Exp::ET_MRTZ)
-    O << " mrtz";
-  else if (Tgt == Exp::ET_NULL)
-    O << " null";
-  else if (Tgt >= Exp::ET_POS0 &&
-           Tgt <= uint32_t(isGFX10Plus(STI) ? Exp::ET_POS4 : Exp::ET_POS3))
-    O << " pos" << Tgt - Exp::ET_POS0;
-  else if (isGFX10Plus(STI) && Tgt == Exp::ET_PRIM)
-    O << " prim";
-  else if (Tgt >= Exp::ET_PARAM0 && Tgt <= Exp::ET_PARAM31)
-    O << " param" << Tgt - Exp::ET_PARAM0;
-  else {
-    // Reserved values 10, 11
-    O << " invalid_target_" << Tgt;
+  uint32_t Id = MI->getOperand(OpNo).getImm() & ((1 << 6) - 1);
+
+  int Index;
+  StringRef TgtName;
+  if (getTgtName(Id, TgtName, Index) && isSupportedTgtId(Id, STI)) {
+    O << ' ' << TgtName;
+    if (Index >= 0)
+      O << Index;
+  } else {
+    O << " invalid_target_" << Id;
   }
 }
 
Index: llvm/lib/Target/AMDGPU/SIDefines.h
===================================================================
--- llvm/lib/Target/AMDGPU/SIDefines.h
+++ llvm/lib/Target/AMDGPU/SIDefines.h
@@ -704,6 +704,7 @@
   ET_PRIM = 20,          // GFX10+
   ET_PARAM0 = 32,
   ET_PARAM31 = 63,
+  ET_INVALID = 255,
 };
 
 } // namespace Exp
Index: llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.h
===================================================================
--- llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.h
+++ llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.h
@@ -486,6 +486,18 @@
 
 } // namespace Hwreg
 
+namespace Exp {
+
+bool getTgtName(unsigned Id, StringRef &Name, int &Index);
+
+LLVM_READONLY
+unsigned getTgtId(const StringRef Name);
+
+LLVM_READNONE
+bool isSupportedTgtId(unsigned Id, const MCSubtargetInfo &STI);
+
+} // namespace Exp
+
 namespace MTBUFFormat {
 
 LLVM_READNONE
Index: llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
===================================================================
--- llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
+++ llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
@@ -787,6 +787,67 @@
 
 } // namespace Hwreg
 
+//===----------------------------------------------------------------------===//
+// exp tgt
+//===----------------------------------------------------------------------===//
+
+namespace Exp {
+
+struct ExpTgt {
+  StringLiteral Name;
+  unsigned Tgt;
+  unsigned MaxIndex;
+};
+
+static constexpr ExpTgt ExpTgtInfo[] = {
+  {{"null"},  ET_NULL,    0},
+  {{"mrtz"},  ET_MRTZ,    0},
+  {{"prim"},  ET_PRIM,    0},
+  {{"mrt"},   ET_MRT0,    7},
+  {{"pos"},   ET_POS0,    7},
+  {{"param"}, ET_PARAM0, 31},
+};
+
+bool getTgtName(unsigned Id, StringRef &Name, int &Index) {
+  for (const ExpTgt &Val : ExpTgtInfo) {
+    if (Val.Tgt <= Id && Id <= Val.Tgt + Val.MaxIndex) {
+      Index = (Val.MaxIndex == 0) ? -1 : (Id - Val.Tgt);
+      Name = Val.Name;
+      return true;
+    }
+  }
+  return false;
+}
+
+unsigned getTgtId(const StringRef Name) {
+
+  for (const ExpTgt &Val : ExpTgtInfo) {
+    if (Val.MaxIndex == 0 && Name == Val.Name)
+      return Val.Tgt;
+
+    if (Val.MaxIndex > 0 && Name.startswith(Val.Name)) {
+      StringRef Suffix = Name.drop_front(Val.Name.size());
+
+      unsigned Id;
+      if (Suffix.getAsInteger(10, Id) || Id > Val.MaxIndex)
+        return ET_INVALID;
+
+      // Disable leading zeroes
+      if (Suffix.size() > 1 && Suffix[0] == '0')
+        return ET_INVALID;
+
+      return Val.Tgt + Id;
+    }
+  }
+  return ET_INVALID;
+}
+
+bool isSupportedTgtId(unsigned Id, const MCSubtargetInfo &STI) {
+  return (Id != ET_POS4 && Id != ET_PRIM) || isGFX10Plus(STI);
+}
+
+} // namespace Exp
+
 //===----------------------------------------------------------------------===//
 // MTBUF Format
 //===----------------------------------------------------------------------===//
Index: llvm/test/MC/AMDGPU/exp-err.s
===================================================================
--- llvm/test/MC/AMDGPU/exp-err.s
+++ llvm/test/MC/AMDGPU/exp-err.s
@@ -5,7 +5,7 @@
 // GCN: :5: error: invalid exp target
 
 exp pos4 v3, v2, v1, v0
-// GCN: :5: error: invalid exp target
+// GCN: :5: error: exp target is not supported on this GPU
 
 exp param32 v3, v2, v1, v0
 // GCN: :5: error: invalid exp target
Index: llvm/test/MC/AMDGPU/exp-gfx10.s
===================================================================
--- llvm/test/MC/AMDGPU/exp-gfx10.s
+++ llvm/test/MC/AMDGPU/exp-gfx10.s
@@ -3,13 +3,13 @@
 // RUN: llvm-mc -arch=amdgcn -mcpu=gfx1010 -show-encoding %s | FileCheck -check-prefix=GFX10 %s
 
 exp prim v1, off, off, off
-// SIVI: :5: error: invalid exp target
+// SIVI: :5: error: exp target is not supported on this GPU
 // GFX10: exp prim v1, off, off, off ; encoding: [0x41,0x01,0x00,0xf8,0x01,0x00,0x00,0x00]
 
 exp prim v2, v3, off, off
-// SIVI: :5: error: invalid exp target
+// SIVI: :5: error: exp target is not supported on this GPU
 // GFX10: exp prim v2, v3, off, off ; encoding: [0x43,0x01,0x00,0xf8,0x02,0x03,0x00,0x00]
 
 exp pos4 v4, v3, v2, v1
-// SIVI: error: invalid exp target
+// SIVI: error: exp target is not supported on this GPU
 // GFX10: exp pos4 v4, v3, v2, v1 ; encoding: [0x0f,0x01,0x00,0xf8,0x04,0x03,0x02,0x01]
Index: llvm/test/MC/AMDGPU/gfx10_err_pos.s
===================================================================
--- llvm/test/MC/AMDGPU/gfx10_err_pos.s
+++ llvm/test/MC/AMDGPU/gfx10_err_pos.s
@@ -631,6 +631,11 @@
 // CHECK-NEXT:{{^}}exp invalid_target_10 v3, v2, v1, v0
 // CHECK-NEXT:{{^}}    ^
 
+exp pos00 v3, v2, v1, v0
+// CHECK: error: invalid exp target
+// CHECK-NEXT:{{^}}exp pos00 v3, v2, v1, v0
+// CHECK-NEXT:{{^}}    ^
+
 //==============================================================================
 // invalid immediate: only 16-bit values are legal
 
Index: llvm/test/MC/AMDGPU/gfx9_err_pos.s
===================================================================
--- llvm/test/MC/AMDGPU/gfx9_err_pos.s
+++ llvm/test/MC/AMDGPU/gfx9_err_pos.s
@@ -24,6 +24,14 @@
 // CHECK-NEXT:{{^}}s_set_gpr_idx_on s0, gpr_idx(SRC0,DST,SRC1,DST)
 // CHECK-NEXT:{{^}}                                           ^
 
+//==============================================================================
+// exp target is not supported on this GPU
+
+exp pos4 v4, v3, v2, v1
+// CHECK: error: exp target is not supported on this GPU
+// CHECK-NEXT:{{^}}exp pos4 v4, v3, v2, v1
+// CHECK-NEXT:{{^}}    ^
+
 //==============================================================================
 // expected a 12-bit unsigned offset