diff --git a/llvm/lib/Transforms/AggressiveInstCombine/TruncInstCombine.cpp b/llvm/lib/Transforms/AggressiveInstCombine/TruncInstCombine.cpp
--- a/llvm/lib/Transforms/AggressiveInstCombine/TruncInstCombine.cpp
+++ b/llvm/lib/Transforms/AggressiveInstCombine/TruncInstCombine.cpp
@@ -66,9 +66,14 @@
   case Instruction::Shl:
   case Instruction::LShr:
   case Instruction::AShr:
+  case Instruction::InsertElement:
+  case Instruction::ShuffleVector:
     Ops.push_back(I->getOperand(0));
     Ops.push_back(I->getOperand(1));
     break;
+  case Instruction::ExtractElement:
+    Ops.push_back(I->getOperand(0));
+    break;
   case Instruction::Select:
     Ops.push_back(I->getOperand(1));
     Ops.push_back(I->getOperand(2));
@@ -135,6 +140,9 @@
     case Instruction::Shl:
     case Instruction::LShr:
     case Instruction::AShr:
+    case Instruction::InsertElement:
+    case Instruction::ExtractElement:
+    case Instruction::ShuffleVector:
     case Instruction::Select: {
       SmallVector<Value *, 2> Operands;
       getRelevantOperands(I, Operands);
@@ -143,9 +151,8 @@
     }
     default:
       // TODO: Can handle more cases here:
-      // 1. shufflevector, extractelement, insertelement
-      // 2. udiv, urem
-      // 3. phi node(and loop handling)
+      // 1. udiv, urem
+      // 2. phi node(and loop handling)
       // ...
       return false;
     }
@@ -408,6 +415,26 @@
           ResI->setIsExact(PEO->isExact());
       break;
     }
+    case Instruction::ExtractElement: {
+      Value *Vec = getReducedOperand(I->getOperand(0), SclTy);
+      Value *Idx = I->getOperand(1);
+      Res = Builder.CreateExtractElement(Vec, Idx);
+      break;
+    }
+    case Instruction::InsertElement: {
+      Value *Vec = getReducedOperand(I->getOperand(0), SclTy);
+      Value *NewElt = getReducedOperand(I->getOperand(1), SclTy);
+      Value *Idx = I->getOperand(2);
+      Res = Builder.CreateInsertElement(Vec, NewElt, Idx);
+      break;
+    }
+    case Instruction::ShuffleVector: {
+      Value *V1 = getReducedOperand(I->getOperand(0), SclTy);
+      Value *V2 = getReducedOperand(I->getOperand(1), SclTy);
+      Res = Builder.CreateShuffleVector(
+          V1, V2, cast<ShuffleVectorInst>(I)->getShuffleMask());
+      break;
+    }
     case Instruction::Select: {
       Value *Op0 = I->getOperand(0);
       Value *LHS = getReducedOperand(I->getOperand(1), SclTy);
diff --git a/llvm/test/Transforms/AggressiveInstCombine/trunc_vector_instrs.ll b/llvm/test/Transforms/AggressiveInstCombine/trunc_vector_instrs.ll
--- a/llvm/test/Transforms/AggressiveInstCombine/trunc_vector_instrs.ll
+++ b/llvm/test/Transforms/AggressiveInstCombine/trunc_vector_instrs.ll
@@ -3,11 +3,10 @@
 
 define <4 x i16> @shuffle(<2 x i8> %a, <2 x i8> %b) {
 ; CHECK-LABEL: @shuffle(
-; CHECK-NEXT:    [[ZEXTA:%.*]] = zext <2 x i8> [[A:%.*]] to <2 x i32>
-; CHECK-NEXT:    [[ZEXTB:%.*]] = zext <2 x i8> [[B:%.*]] to <2 x i32>
-; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <2 x i32> [[ZEXTA]], <2 x i32> [[ZEXTB]], <4 x i32> <i32 3, i32 2, i32 1, i32 0>
-; CHECK-NEXT:    [[TRUNC:%.*]] = trunc <4 x i32> [[SHUF]] to <4 x i16>
-; CHECK-NEXT:    ret <4 x i16> [[TRUNC]]
+; CHECK-NEXT:    [[ZEXTA:%.*]] = zext <2 x i8> [[A:%.*]] to <2 x i16>
+; CHECK-NEXT:    [[ZEXTB:%.*]] = zext <2 x i8> [[B:%.*]] to <2 x i16>
+; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <2 x i16> [[ZEXTA]], <2 x i16> [[ZEXTB]], <4 x i32> <i32 3, i32 2, i32 1, i32 0>
+; CHECK-NEXT:    ret <4 x i16> [[SHUF]]
 ;
   %zexta = zext <2 x i8> %a to <2 x i32>
   %zextb = zext <2 x i8> %b to <2 x i32>
@@ -18,10 +17,9 @@
 
 define <2 x i16> @unary_shuffle(<2 x i8> %a) {
 ; CHECK-LABEL: @unary_shuffle(
-; CHECK-NEXT:    [[ZEXTA:%.*]] = zext <2 x i8> [[A:%.*]] to <2 x i32>
-; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <2 x i32> [[ZEXTA]], <2 x i32> undef, <2 x i32> <i32 1, i32 0>
-; CHECK-NEXT:    [[TRUNC:%.*]] = trunc <2 x i32> [[SHUF]] to <2 x i16>
-; CHECK-NEXT:    ret <2 x i16> [[TRUNC]]
+; CHECK-NEXT:    [[ZEXTA:%.*]] = zext <2 x i8> [[A:%.*]] to <2 x i16>
+; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <2 x i16> [[ZEXTA]], <2 x i16> undef, <2 x i32> <i32 1, i32 0>
+; CHECK-NEXT:    ret <2 x i16> [[SHUF]]
 ;
   %zexta = zext <2 x i8> %a to <2 x i32>
   %shuf = shufflevector <2 x i32> %zexta, <2 x i32> undef, <2 x i32> <i32 1, i32 0>
@@ -31,9 +29,7 @@
 
 define <4 x i16> @const_shuffle() {
 ; CHECK-LABEL: @const_shuffle(
-; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <2 x i32> <i32 1, i32 2>, <2 x i32> <i32 3, i32 7>, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
-; CHECK-NEXT:    [[TRUNC:%.*]] = trunc <4 x i32> [[SHUF]] to <4 x i16>
-; CHECK-NEXT:    ret <4 x i16> [[TRUNC]]
+; CHECK-NEXT:    ret <4 x i16> <i16 7, i16 3, i16 2, i16 1>
 ;
   %shuf = shufflevector <2 x i32> <i32 1, i32 2>, <2 x i32> <i32 3, i32 7>, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
   %trunc = trunc <4 x i32> %shuf to <4 x i16>
@@ -43,12 +39,11 @@
 
 define <2 x i16> @extract_insert(<2 x i8> %a, <2 x i8> %b) {
 ; CHECK-LABEL: @extract_insert(
-; CHECK-NEXT:    [[ZEXTA:%.*]] = zext <2 x i8> [[A:%.*]] to <2 x i32>
-; CHECK-NEXT:    [[ZEXTB:%.*]] = zext <2 x i8> [[B:%.*]] to <2 x i32>
-; CHECK-NEXT:    [[EXTR:%.*]] = extractelement <2 x i32> [[ZEXTA]], i32 0
-; CHECK-NEXT:    [[INSR:%.*]] = insertelement <2 x i32> [[ZEXTB]], i32 [[EXTR]], i32 1
-; CHECK-NEXT:    [[TRUNC:%.*]] = trunc <2 x i32> [[INSR]] to <2 x i16>
-; CHECK-NEXT:    ret <2 x i16> [[TRUNC]]
+; CHECK-NEXT:    [[ZEXTA:%.*]] = zext <2 x i8> [[A:%.*]] to <2 x i16>
+; CHECK-NEXT:    [[ZEXTB:%.*]] = zext <2 x i8> [[B:%.*]] to <2 x i16>
+; CHECK-NEXT:    [[EXTR:%.*]] = extractelement <2 x i16> [[ZEXTA]], i32 0
+; CHECK-NEXT:    [[INSR:%.*]] = insertelement <2 x i16> [[ZEXTB]], i16 [[EXTR]], i32 1
+; CHECK-NEXT:    ret <2 x i16> [[INSR]]
 ;
   %zexta = zext <2 x i8> %a to <2 x i32>
   %zextb = zext <2 x i8> %b to <2 x i32>
@@ -60,10 +55,9 @@
 
 define <2 x i16> @insert_poison(i8 %a) {
 ; CHECK-LABEL: @insert_poison(
-; CHECK-NEXT:    [[ZEXTA:%.*]] = zext i8 [[A:%.*]] to i32
-; CHECK-NEXT:    [[INSR:%.*]] = insertelement <2 x i32> poison, i32 [[ZEXTA]], i32 0
-; CHECK-NEXT:    [[TRUNC:%.*]] = trunc <2 x i32> [[INSR]] to <2 x i16>
-; CHECK-NEXT:    ret <2 x i16> [[TRUNC]]
+; CHECK-NEXT:    [[ZEXTA:%.*]] = zext i8 [[A:%.*]] to i16
+; CHECK-NEXT:    [[INSR:%.*]] = insertelement <2 x i16> poison, i16 [[ZEXTA]], i32 0
+; CHECK-NEXT:    ret <2 x i16> [[INSR]]
 ;
   %zexta = zext i8 %a to i32
   %insr = insertelement <2 x i32> poison, i32 %zexta, i32 0