diff --git a/llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp b/llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
index 0874b29ab7d22..019536ca91ae0 100644
--- a/llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
@@ -1598,11 +1598,8 @@ bool LoopIdiomRecognize::optimizeCRCLoop(const PolynomialInfo &Info) {
   //   crc = (crc << 8) ^ tbl[(iv'th byte of data) ^ (top byte of crc)]
   {
     auto LoByte = [](IRBuilderBase &Builder, Value *Op, const Twine &Name) {
-      Type *OpTy = Op->getType();
-      unsigned OpBW = OpTy->getIntegerBitWidth();
-      return OpBW > 8
-                 ? Builder.CreateAnd(Op, ConstantInt::get(OpTy, 0XFF), Name)
-                 : Op;
+      return Builder.CreateZExtOrTrunc(
+          Op, IntegerType::getInt8Ty(Op->getContext()), Name);
     };
     auto HiIdx = [LoByte, CRCBW](IRBuilderBase &Builder, Value *Op,
                                  const Twine &Name) {
diff --git a/llvm/test/Transforms/LoopIdiom/cyclic-redundancy-check-dl.ll b/llvm/test/Transforms/LoopIdiom/cyclic-redundancy-check-dl.ll
new file mode 100644
index 0000000000000..14a4c952d3510
--- /dev/null
+++ b/llvm/test/Transforms/LoopIdiom/cyclic-redundancy-check-dl.ll
@@ -0,0 +1,50 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals all --version 6
+; RUN: opt -passes=loop-idiom -S %s | FileCheck %s
+
+target datalayout = "p:16:16"
+
+;.
+; CHECK: @.crctable = private constant [256 x i32] zeroinitializer
+;.
+define void @test_with_dl() {
+; CHECK-LABEL: define void @test_with_dl() {
+; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    br label %[[PH:.*]]
+; CHECK:       [[PH_LOOPEXIT:.*]]:
+; CHECK-NEXT:    [[CRC_NEXT_LCSSA:%.*]] = phi i32 [ [[CRC_NEXT3:%.*]], %[[LOOP:.*]] ]
+; CHECK-NEXT:    br label %[[PH]]
+; CHECK:       [[PH]]:
+; CHECK-NEXT:    [[CRC_USE:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[CRC_NEXT_LCSSA]], %[[PH_LOOPEXIT]] ]
+; CHECK-NEXT:    br label %[[LOOP]]
+; CHECK:       [[LOOP]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i16 [ 0, %[[PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT:    [[CRC2:%.*]] = phi i32 [ 0, %[[PH]] ], [ [[CRC_NEXT3]], %[[LOOP]] ]
+; CHECK-NEXT:    [[INDEXER_LO:%.*]] = trunc i32 [[CRC2]] to i8
+; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i8 [[INDEXER_LO]] to i16
+; CHECK-NEXT:    [[TBL_PTRADD:%.*]] = getelementptr inbounds i32, ptr @.crctable, i16 [[INDEXER_EXT]]
+; CHECK-NEXT:    [[TBL_LD:%.*]] = load i32, ptr [[TBL_PTRADD]], align 4
+; CHECK-NEXT:    [[CRC_LE_SHIFT:%.*]] = lshr i32 [[CRC2]], 8
+; CHECK-NEXT:    [[CRC_NEXT3]] = xor i32 [[CRC_LE_SHIFT]], [[TBL_LD]]
+; CHECK-NEXT:    [[IV_NEXT]] = add i16 [[IV]], 1
+; CHECK-NEXT:    [[EXIT_COND1:%.*]] = icmp ne i16 [[IV]], 0
+; CHECK-NEXT:    br i1 [[EXIT_COND1]], label %[[LOOP]], label %[[PH_LOOPEXIT]]
+;
+entry:
+  br label %ph
+
+ph:
+  %crc.use = phi i32 [ 0, %entry ], [ %crc.next, %loop ]
+  br label %loop
+
+loop:
+  %iv = phi i16 [ 0, %ph ], [ %iv.next, %loop ]
+  %crc = phi i32 [ 0, %ph ], [ %crc.next, %loop ]
+  %lshr.crc.1 = lshr i32 %crc, 1
+  %crc.and.1 = and i32 %crc, 1
+  %sb.check = icmp eq i32 %crc.and.1, 0
+  %xor = xor i32 %lshr.crc.1, 0
+  %crc.next = select i1 %sb.check, i32 %lshr.crc.1, i32 %xor
+  %iv.next = add i16 %iv, 1
+  %exit.cond = icmp ult i16 %iv, 7
+  br i1 %exit.cond, label %loop, label %ph
+}
diff --git a/llvm/test/Transforms/LoopIdiom/cyclic-redundancy-check.ll b/llvm/test/Transforms/LoopIdiom/cyclic-redundancy-check.ll
index 51dc142200d78..b2ec53ca405d4 100644
--- a/llvm/test/Transforms/LoopIdiom/cyclic-redundancy-check.ll
+++ b/llvm/test/Transforms/LoopIdiom/cyclic-redundancy-check.ll
@@ -118,8 +118,8 @@ define i16 @crc16.le.tc16(i16 %msg, i16 %checksum) {
 ; CHECK-NEXT:    [[IV_INDEXER:%.*]] = zext i8 [[IV_BITS]] to i16
 ; CHECK-NEXT:    [[DATA_INDEXER:%.*]] = lshr i16 [[MSG]], [[IV_INDEXER]]
 ; CHECK-NEXT:    [[CRC_DATA_INDEXER:%.*]] = xor i16 [[DATA_INDEXER]], [[CRC2]]
-; CHECK-NEXT:    [[INDEXER_LO:%.*]] = and i16 [[CRC_DATA_INDEXER]], 255
-; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i16 [[INDEXER_LO]] to i64
+; CHECK-NEXT:    [[INDEXER_LO:%.*]] = trunc i16 [[CRC_DATA_INDEXER]] to i8
+; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i8 [[INDEXER_LO]] to i64
 ; CHECK-NEXT:    [[TBL_PTRADD:%.*]] = getelementptr inbounds i16, ptr @.crctable.2, i64 [[INDEXER_EXT]]
 ; CHECK-NEXT:    [[TBL_LD:%.*]] = load i16, ptr [[TBL_PTRADD]], align 2
 ; CHECK-NEXT:    [[CRC_LE_SHIFT:%.*]] = lshr i16 [[CRC2]], 8
@@ -166,8 +166,8 @@ define i8 @crc8.le.tc16(i16 %msg, i8 %checksum) {
 ; CHECK-NEXT:    [[DATA_INDEXER:%.*]] = lshr i16 [[MSG]], [[IV_INDEXER]]
 ; CHECK-NEXT:    [[CRC_INDEXER_CAST:%.*]] = zext i8 [[CRC2]] to i16
 ; CHECK-NEXT:    [[CRC_DATA_INDEXER:%.*]] = xor i16 [[DATA_INDEXER]], [[CRC_INDEXER_CAST]]
-; CHECK-NEXT:    [[INDEXER_LO:%.*]] = and i16 [[CRC_DATA_INDEXER]], 255
-; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i16 [[INDEXER_LO]] to i64
+; CHECK-NEXT:    [[INDEXER_LO:%.*]] = trunc i16 [[CRC_DATA_INDEXER]] to i8
+; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i8 [[INDEXER_LO]] to i64
 ; CHECK-NEXT:    [[TBL_PTRADD:%.*]] = getelementptr inbounds i8, ptr @.crctable.3, i64 [[INDEXER_EXT]]
 ; CHECK-NEXT:    [[TBL_LD]] = load i8, ptr [[TBL_PTRADD]], align 1
 ; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i8 [[IV]], 1
@@ -212,8 +212,8 @@ define i16 @crc16.be.tc8.crc.init.li(i16 %checksum, i8 %msg) {
 ; CHECK-NEXT:    [[IV:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[CRC2:%.*]] = phi i16 [ [[CRC_INIT]], %[[ENTRY]] ], [ [[CRC_NEXT3:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[INDEXER_HI:%.*]] = lshr i16 [[CRC2]], 8
-; CHECK-NEXT:    [[INDEXER_HI_LO_BYTE:%.*]] = and i16 [[INDEXER_HI]], 255
-; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i16 [[INDEXER_HI_LO_BYTE]] to i64
+; CHECK-NEXT:    [[INDEXER_HI_LO_BYTE:%.*]] = trunc i16 [[INDEXER_HI]] to i8
+; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i8 [[INDEXER_HI_LO_BYTE]] to i64
 ; CHECK-NEXT:    [[TBL_PTRADD:%.*]] = getelementptr inbounds i16, ptr @.crctable.4, i64 [[INDEXER_EXT]]
 ; CHECK-NEXT:    [[TBL_LD:%.*]] = load i16, ptr [[TBL_PTRADD]], align 2
 ; CHECK-NEXT:    [[CRC_BE_SHIFT:%.*]] = shl i16 [[CRC2]], 8
@@ -255,8 +255,8 @@ define i16 @crc16.be.tc8.crc.init.arg(i16 %crc.init) {
 ; CHECK-NEXT:    [[IV:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[CRC2:%.*]] = phi i16 [ [[CRC_INIT]], %[[ENTRY]] ], [ [[CRC_NEXT3:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[INDEXER_HI:%.*]] = lshr i16 [[CRC2]], 8
-; CHECK-NEXT:    [[INDEXER_HI_LO_BYTE:%.*]] = and i16 [[INDEXER_HI]], 255
-; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i16 [[INDEXER_HI_LO_BYTE]] to i64
+; CHECK-NEXT:    [[INDEXER_HI_LO_BYTE:%.*]] = trunc i16 [[INDEXER_HI]] to i8
+; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i8 [[INDEXER_HI_LO_BYTE]] to i64
 ; CHECK-NEXT:    [[TBL_PTRADD:%.*]] = getelementptr inbounds i16, ptr @.crctable.5, i64 [[INDEXER_EXT]]
 ; CHECK-NEXT:    [[TBL_LD:%.*]] = load i16, ptr [[TBL_PTRADD]], align 2
 ; CHECK-NEXT:    [[CRC_BE_SHIFT:%.*]] = shl i16 [[CRC2]], 8
@@ -295,8 +295,8 @@ define i16 @crc16.be.tc8.crc.init.arg.flipped.sb.check(i16 %crc.init) {
 ; CHECK-NEXT:    [[IV:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[CRC2:%.*]] = phi i16 [ [[CRC_INIT]], %[[ENTRY]] ], [ [[CRC_NEXT3:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[INDEXER_HI:%.*]] = lshr i16 [[CRC2]], 8
-; CHECK-NEXT:    [[INDEXER_HI_LO_BYTE:%.*]] = and i16 [[INDEXER_HI]], 255
-; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i16 [[INDEXER_HI_LO_BYTE]] to i64
+; CHECK-NEXT:    [[INDEXER_HI_LO_BYTE:%.*]] = trunc i16 [[INDEXER_HI]] to i8
+; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i8 [[INDEXER_HI_LO_BYTE]] to i64
 ; CHECK-NEXT:    [[TBL_PTRADD:%.*]] = getelementptr inbounds i16, ptr @.crctable.6, i64 [[INDEXER_EXT]]
 ; CHECK-NEXT:    [[TBL_LD:%.*]] = load i16, ptr [[TBL_PTRADD]], align 2
 ; CHECK-NEXT:    [[CRC_BE_SHIFT:%.*]] = shl i16 [[CRC2]], 8
@@ -406,8 +406,8 @@ define i32 @crc32.le.tc8.data32(i32 %checksum, i32 %msg) {
 ; CHECK-NEXT:    [[IV_INDEXER:%.*]] = zext i8 [[IV_BITS]] to i32
 ; CHECK-NEXT:    [[DATA_INDEXER:%.*]] = lshr i32 [[MSG]], [[IV_INDEXER]]
 ; CHECK-NEXT:    [[CRC_DATA_INDEXER:%.*]] = xor i32 [[DATA_INDEXER]], [[CRC2]]
-; CHECK-NEXT:    [[INDEXER_LO:%.*]] = and i32 [[CRC_DATA_INDEXER]], 255
-; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i32 [[INDEXER_LO]] to i64
+; CHECK-NEXT:    [[INDEXER_LO:%.*]] = trunc i32 [[CRC_DATA_INDEXER]] to i8
+; CHECK-NEXT:    [[INDEXER_EXT:%.*]] = zext i8 [[INDEXER_LO]] to i64
 ; CHECK-NEXT:    [[TBL_PTRADD:%.*]] = getelementptr inbounds i32, ptr @.crctable.8, i64 [[INDEXER_EXT]]
 ; CHECK-NEXT:    [[TBL_LD:%.*]] = load i32, ptr [[TBL_PTRADD]], align 4
 ; CHECK-NEXT:    [[CRC_LE_SHIFT:%.*]] = lshr i32 [[CRC2]], 8