Index: lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.h
===================================================================
--- lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.h
+++ lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.h
@@ -69,13 +69,13 @@
     MCOperand decodeOperand_SReg_256(unsigned Val) const;
     MCOperand decodeOperand_SReg_512(unsigned Val) const;
 
-    enum { OP32 = true, OP64 = false };
+    enum OpWidthTy { OPW32, OPW64, OPW128, OPW_LAST_, OPW_FIRST_ = OPW32 };
 
     static MCOperand decodeIntImmed(unsigned Imm);
     static MCOperand decodeFPImmed(bool Is32, unsigned Imm);
     MCOperand decodeLiteralConstant() const;
 
-    MCOperand decodeSrcOp(bool Is32, unsigned Val) const;
+    MCOperand decodeSrcOp(const OpWidthTy Width, unsigned Val) const;
     MCOperand decodeSpecialReg32(unsigned Val) const;
     MCOperand decodeSpecialReg64(unsigned Val) const;
   };
Index: lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp
===================================================================
--- lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp
+++ lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp
@@ -193,10 +193,11 @@
   int shift = 0;
   switch (SRegClassID) {
   case AMDGPU::SGPR_32RegClassID:
-  case AMDGPU::SReg_32RegClassID: break;
+  case AMDGPU::TTMP_32RegClassID: break;
   case AMDGPU::SGPR_64RegClassID:
-  case AMDGPU::SReg_64RegClassID:  shift = 1; break;
-  case AMDGPU::SReg_128RegClassID:
+  case AMDGPU::TTMP_64RegClassID: shift = 1; break;
+  case AMDGPU::SGPR_128RegClassID:
+  case AMDGPU::TTMP_128RegClassID:
   // ToDo: unclear if s[100:104] is available on VI. Can we use VCC as SGPR in
   // this bundle?
   case AMDGPU::SReg_256RegClassID:
@@ -214,11 +215,11 @@
 }
 
 MCOperand AMDGPUDisassembler::decodeOperand_VS_32(unsigned Val) const {
-  return decodeSrcOp(OP32, Val);
+  return decodeSrcOp(OPW32, Val);
 }
 
 MCOperand AMDGPUDisassembler::decodeOperand_VS_64(unsigned Val) const {
-  return decodeSrcOp(OP64, Val);
+  return decodeSrcOp(OPW64, Val);
 }
 
 MCOperand AMDGPUDisassembler::decodeOperand_VGPR_32(unsigned Val) const {
@@ -241,7 +242,7 @@
   // table-gen generated disassembler doesn't care about operand types
   // leaving only registry class so SSrc_32 operand turns into SReg_32
   // and therefore we accept immediates and literals here as well
-  return decodeSrcOp(OP32, Val);
+  return decodeSrcOp(OPW32, Val);
 }
 
 MCOperand AMDGPUDisassembler::decodeOperand_SReg_32_XM0(unsigned Val) const {
@@ -251,11 +252,11 @@
 
 MCOperand AMDGPUDisassembler::decodeOperand_SReg_64(unsigned Val) const {
   // see decodeOperand_SReg_32 comment
-  return decodeSrcOp(OP64, Val);
+  return decodeSrcOp(OPW64, Val);
 }
 
 MCOperand AMDGPUDisassembler::decodeOperand_SReg_128(unsigned Val) const {
-  return createSRegOperand(AMDGPU::SReg_128RegClassID, Val);
+  return decodeSrcOp(OPW128, Val);
 }
 
 MCOperand AMDGPUDisassembler::decodeOperand_SReg_256(unsigned Val) const {
@@ -305,16 +306,44 @@
   return MCOperand::createImm(Is32? FloatToBits(V) : DoubleToBits(V));
 }
 
-MCOperand AMDGPUDisassembler::decodeSrcOp(bool Is32, unsigned Val) const {
+MCOperand AMDGPUDisassembler::decodeSrcOp(const OpWidthTy Width, unsigned Val) const {
   using namespace AMDGPU;
   assert(Val < 512); // enum9
+  assert(OPW_FIRST_ <= Width && Width < OPW_LAST_);
+
+  if (Val >= 256) {
+    unsigned RegClassId = 0;
+    switch(Width) {
+    default: // fall
+    case OPW32:  RegClassId = VGPR_32RegClassID;  break;
+    case OPW64:  RegClassId = VReg_64RegClassID;  break;
+    case OPW128: RegClassId = VReg_128RegClassID; break;
+    }
+    return createRegOperand(RegClassId,Val - 256);
+  }
+  if (0 <= Val && Val < 102) {
+    unsigned RegClassId = 0;
+    switch(Width) {
+    default: // fall
+    case OPW32:  RegClassId = SGPR_32RegClassID;  break;
+    case OPW64:  RegClassId = SGPR_64RegClassID;  break;
+    case OPW128: RegClassId = SGPR_128RegClassID; break;
+    }
+    return createSRegOperand(RegClassId, Val);
+  }
+  if (112 <= Val && Val < 124) {
+    unsigned RegClassId = 0;
+    switch(Width) {
+    default: // fall
+    case OPW32:  RegClassId = TTMP_32RegClassID;  break;
+    case OPW64:  RegClassId = TTMP_64RegClassID;  break;
+    case OPW128: RegClassId = TTMP_128RegClassID; break;
+    }
+    return createSRegOperand(RegClassId, Val - 112);
+  }
 
-  if (Val >= 256)
-    return createRegOperand(Is32 ? VGPR_32RegClassID : VReg_64RegClassID,
-                            Val - 256);
-  if (Val <= 101)
-    return createSRegOperand(Is32 ? SGPR_32RegClassID : SGPR_64RegClassID,
-                             Val);
+  assert(Width == OPW32 || Width == OPW64);
+  const bool Is32 = (Width == OPW32);
 
   if (Val >= 128 && Val <= 208)
     return decodeIntImmed(Val);
@@ -338,25 +367,10 @@
   case 105: break;
   case 106: return createRegOperand(VCC_LO);
   case 107: return createRegOperand(VCC_HI);
-    // ToDo: no support for tba_lo/_hi register
-  case 108:
-  case 109: break;
-    // ToDo: no support for tma_lo/_hi register
-  case 110:
-  case 111: break;
-    // ToDo: no support for ttmp[0:11] register
-  case 112:
-  case 113:
-  case 114:
-  case 115:
-  case 116:
-  case 117:
-  case 118:
-  case 119:
-  case 120:
-  case 121:
-  case 122:
-  case 123: break;
+  case 108: return createRegOperand(TBA_LO);
+  case 109: return createRegOperand(TBA_HI);
+  case 110: return createRegOperand(TMA_LO);
+  case 111: return createRegOperand(TMA_HI);
   case 124: return createRegOperand(M0);
   case 126: return createRegOperand(EXEC_LO);
   case 127: return createRegOperand(EXEC_HI);
@@ -375,6 +389,8 @@
   switch (Val) {
   case 102: return createRegOperand(getMCReg(FLAT_SCR, STI));
   case 106: return createRegOperand(VCC);
+  case 108: return createRegOperand(TBA);
+  case 110: return createRegOperand(TMA);
   case 126: return createRegOperand(EXEC);
   default: break;
   }
Index: test/MC/Disassembler/AMDGPU/trap_vi.txt
===================================================================
--- /dev/null
+++ test/MC/Disassembler/AMDGPU/trap_vi.txt
@@ -0,0 +1,109 @@
+# RUN: llvm-mc -arch=amdgcn -mcpu=tonga -disassemble -show-encoding < %s | FileCheck %s -check-prefix=VI
+
+#===----------------------------------------------------------------------===#
+# Trap Handler related - 32 bit registers
+#===----------------------------------------------------------------------===#
+
+# VI:   s_add_u32 ttmp0, ttmp0, 4       ; encoding: [0x70,0x84,0x70,0x80]
+0x70,0x84,0x70,0x80
+
+# VI:   s_add_u32 ttmp4, 8, ttmp4       ; encoding: [0x88,0x74,0x74,0x80]
+0x88,0x74,0x74,0x80
+
+# VI:   s_add_u32 ttmp4, ttmp4, 0x100   ; encoding: [0x74,0xff,0x74,0x80,0x00,0x01,0x00,0x00]
+0x74,0xff,0x74,0x80,0x00,0x01,0x00,0x00
+
+# VI:   s_add_u32 ttmp4, ttmp4, 4       ; encoding: [0x74,0x84,0x74,0x80]
+0x74,0x84,0x74,0x80
+
+# VI:   s_add_u32 ttmp4, ttmp8, ttmp4   ; encoding: [0x78,0x74,0x74,0x80]
+0x78,0x74,0x74,0x80
+
+# VI:   s_and_b32 ttmp10, ttmp8, 0x80   ; encoding: [0x78,0xff,0x7a,0x86,0x80,0x00,0x00,0x00]
+0x78,0xff,0x7a,0x86,0x80,0x00,0x00,0x00
+
+# VI:   s_and_b32 ttmp9, tma_hi, 0xffff ; encoding: [0x6f,0xff,0x79,0x86,0xff,0xff,0x00,0x00]
+0x6f,0xff,0x79,0x86,0xff,0xff,0x00,0x00
+
+# VI:   s_and_b32 ttmp9, ttmp9, 0x1ff   ; encoding: [0x79,0xff,0x79,0x86,0xff,0x01,0x00,0x00]
+0x79,0xff,0x79,0x86,0xff,0x01,0x00,0x00
+
+# VI:   s_and_b32 ttmp9, tma_lo, 0xffff0000 ; encoding: [0x6e,0xff,0x79,0x86,0x00,0x00,0xff,0xff]
+0x6e,0xff,0x79,0x86,0x00,0x00,0xff,0xff
+
+# VI:   s_and_b32 ttmp9, ttmp9, ttmp8   ; encoding: [0x79,0x78,0x79,0x86]
+0x79,0x78,0x79,0x86
+
+# VI:   s_and_b32 ttmp8, ttmp1, 0x1000000 ; encoding: [0x71,0xff,0x78,0x86,0x00,0x00,0x00,0x01]
+0x71,0xff,0x78,0x86,0x00,0x00,0x00,0x01
+
+# VI:   s_cmp_eq_i32 ttmp8, 0           ; encoding: [0x78,0x80,0x00,0xbf]
+0x78,0x80,0x00,0xbf
+
+# VI:   s_cmp_eq_i32 ttmp8, 0xfe        ; encoding: [0x78,0xff,0x00,0xbf,0xfe,0x00,0x00,0x00]
+0x78,0xff,0x00,0xbf,0xfe,0x00,0x00,0x00
+
+# VI:   s_lshr_b32 ttmp8, ttmp8, 12     ; encoding: [0x78,0x8c,0x78,0x8f]
+0x78,0x8c,0x78,0x8f
+
+# VI:   v_mov_b32_e32 v1, ttmp8         ; encoding: [0x78,0x02,0x02,0x7e]
+0x78,0x02,0x02,0x7e
+
+# VI:   s_mov_b32 m0, ttmp8             ; encoding: [0x78,0x00,0xfc,0xbe]
+0x78,0x00,0xfc,0xbe
+
+# VI:   s_mov_b32 ttmp10, 0             ; encoding: [0x80,0x00,0xfa,0xbe]
+0x80,0x00,0xfa,0xbe
+
+# VI:   s_mov_b32 ttmp11, 0x1024fac     ; encoding: [0xff,0x00,0xfb,0xbe,0xac,0x4f,0x02,0x01]
+0xff,0x00,0xfb,0xbe,0xac,0x4f,0x02,0x01
+
+# VI:   s_mov_b32 ttmp8, m0             ; encoding: [0x7c,0x00,0xf8,0xbe]
+0x7c,0x00,0xf8,0xbe
+
+# VI:   s_mov_b32 ttmp8, tma_lo         ; encoding: [0x6e,0x00,0xf8,0xbe]
+0x6e,0x00,0xf8,0xbe
+
+# VI:   s_mul_i32 ttmp8, 0x324, ttmp8   ; encoding: [0xff,0x78,0x78,0x92,0x24,0x03,0x00,0x00]
+0xff,0x78,0x78,0x92,0x24,0x03,0x00,0x00
+
+# VI:   s_or_b32 ttmp9, ttmp9, 0x280000 ; encoding: [0x79,0xff,0x79,0x87,0x00,0x00,0x28,0x00]
+0x79,0xff,0x79,0x87,0x00,0x00,0x28,0x00
+
+#===----------------------------------------------------------------------===#
+# Trap Handler related - Pairs and quadruples of registers
+#===----------------------------------------------------------------------===#
+
+# VI:   s_mov_b64 ttmp[4:5], exec       ; encoding: [0x7e,0x01,0xf4,0xbe]
+0x7e,0x01,0xf4,0xbe
+
+# VI:   s_mov_b64 ttmp[4:5], exec       ; encoding: [0x7e,0x01,0xf4,0xbe]
+0x7e,0x01,0xf4,0xbe
+
+# VI:   s_mov_b64 exec, ttmp[4:5]       ; encoding: [0x74,0x01,0xfe,0xbe]
+0x74,0x01,0xfe,0xbe
+
+# VI:   s_mov_b64 tba, ttmp[4:5]        ; encoding: [0x74,0x01,0xec,0xbe]
+0x74,0x01,0xec,0xbe
+
+# VI:   s_mov_b64 ttmp[4:5], tba        ; encoding: [0x6c,0x01,0xf4,0xbe]
+0x6c,0x01,0xf4,0xbe
+
+# VI:   s_mov_b64 tma, ttmp[4:5]        ; encoding: [0x74,0x01,0xee,0xbe]
+0x74,0x01,0xee,0xbe
+
+# VI:   s_mov_b64 ttmp[4:5], tma        ; encoding: [0x6e,0x01,0xf4,0xbe]
+0x6e,0x01,0xf4,0xbe
+
+#===----------------------------------------------------------------------===#
+# Trap Handler related - Some specific instructions
+#===----------------------------------------------------------------------===#
+
+# VI:   s_setpc_b64 ttmp[2:3]           ; encoding: [0x72,0x1d,0x80,0xbe]
+0x72,0x1d,0x80,0xbe
+
+# VI:   v_readfirstlane_b32 ttmp8, v1   ; encoding: [0x01,0x05,0xf0,0x7e]
+0x01,0x05,0xf0,0x7e
+
+# VI:   buffer_atomic_inc v1, off, ttmp[8:11], 56  glc ; encoding: [0x00,0x40,0x2c,0xe1,0x00,0x01,0x1e,0xb8]
+0x00,0x40,0x2c,0xe1,0x00,0x01,0x1e,0xb8