diff --git a/llvm/include/llvm/IR/IntrinsicsPowerPC.td b/llvm/include/llvm/IR/IntrinsicsPowerPC.td
--- a/llvm/include/llvm/IR/IntrinsicsPowerPC.td
+++ b/llvm/include/llvm/IR/IntrinsicsPowerPC.td
@@ -495,6 +495,9 @@
   def int_ppc_altivec_vmsumuhm : GCCBuiltin<"__builtin_altivec_vmsumuhm">,
             Intrinsic<[llvm_v4i32_ty], [llvm_v8i16_ty, llvm_v8i16_ty,
                        llvm_v4i32_ty], [IntrNoMem]>;
+  def int_ppc_altivec_vmsumudm : GCCBuiltin<"__builtin_altivec_vmsumudm">,
+            Intrinsic<[llvm_v1i128_ty], [llvm_v2i64_ty, llvm_v2i64_ty,
+                       llvm_v1i128_ty], [IntrNoMem]>;
   def int_ppc_altivec_vmsumuhs : GCCBuiltin<"__builtin_altivec_vmsumuhs">,
             Intrinsic<[llvm_v4i32_ty], [llvm_v8i16_ty, llvm_v8i16_ty,
                        llvm_v4i32_ty], [IntrNoMem]>;
diff --git a/llvm/lib/Target/PowerPC/P9InstrResources.td b/llvm/lib/Target/PowerPC/P9InstrResources.td
--- a/llvm/lib/Target/PowerPC/P9InstrResources.td
+++ b/llvm/lib/Target/PowerPC/P9InstrResources.td
@@ -373,6 +373,7 @@
     VMSUMSHS,
     VMSUMUBM,
     VMSUMUHM,
+    VMSUMUDM,
     VMSUMUHS,
     VMULESB,
     VMULESH,
diff --git a/llvm/lib/Target/PowerPC/PPCInstrAltivec.td b/llvm/lib/Target/PowerPC/PPCInstrAltivec.td
--- a/llvm/lib/Target/PowerPC/PPCInstrAltivec.td
+++ b/llvm/lib/Target/PowerPC/PPCInstrAltivec.td
@@ -1362,6 +1362,10 @@
 def HasP9Altivec : Predicate<"PPCSubTarget->hasP9Altivec()">;
 let Predicates = [HasP9Altivec] in {
 
+// Vector Multiply-Sum
+def VMSUMUDM : VA1a_Int_Ty3<35, "vmsumudm", int_ppc_altivec_vmsumudm,
+                            v1i128, v2i64, v1i128>;
+
 // i8 element comparisons.
 def VCMPNEB   : VCMP   <  7, "vcmpneb $vD, $vA, $vB"  , v16i8>;
 def VCMPNEB_rec  : VCMPo  <  7, "vcmpneb. $vD, $vA, $vB" , v16i8>;
diff --git a/llvm/test/MC/Disassembler/PowerPC/ppc64-encoding-vmx.txt b/llvm/test/MC/Disassembler/PowerPC/ppc64-encoding-vmx.txt
--- a/llvm/test/MC/Disassembler/PowerPC/ppc64-encoding-vmx.txt
+++ b/llvm/test/MC/Disassembler/PowerPC/ppc64-encoding-vmx.txt
@@ -333,6 +333,9 @@
 # CHECK: vmsumuhm 2, 3, 4, 5             
 0x10 0x43 0x21 0x66
 
+# CHECK: vmsumudm 2, 3, 4, 5
+0x10 0x43 0x21 0x63
+
 # CHECK: vmsumuhs 2, 3, 4, 5             
 0x10 0x43 0x21 0x67
 
diff --git a/llvm/test/MC/PowerPC/ppc64-encoding-vmx.s b/llvm/test/MC/PowerPC/ppc64-encoding-vmx.s
--- a/llvm/test/MC/PowerPC/ppc64-encoding-vmx.s
+++ b/llvm/test/MC/PowerPC/ppc64-encoding-vmx.s
@@ -366,6 +366,9 @@
 # CHECK-BE: vmsumuhm 2, 3, 4, 5             # encoding: [0x10,0x43,0x21,0x66]
 # CHECK-LE: vmsumuhm 2, 3, 4, 5             # encoding: [0x66,0x21,0x43,0x10]
             vmsumuhm 2, 3, 4, 5
+# CHECK-BE: vmsumudm 2, 3, 4, 5             # encoding: [0x10,0x43,0x21,0x63]
+# CHECK-LE: vmsumudm 2, 3, 4, 5             # encoding: [0x63,0x21,0x43,0x10]
+            vmsumudm 2, 3, 4, 5
 # CHECK-BE: vmsumuhs 2, 3, 4, 5             # encoding: [0x10,0x43,0x21,0x67]
 # CHECK-LE: vmsumuhs 2, 3, 4, 5             # encoding: [0x67,0x21,0x43,0x10]
             vmsumuhs 2, 3, 4, 5