diff --git a/llvm/test/Instrumentation/MemorySanitizer/bitreverse.ll b/llvm/test/Instrumentation/MemorySanitizer/bitreverse.ll
new file mode 100644
index 0000000000000..72aefe3065e40
--- /dev/null
+++ b/llvm/test/Instrumentation/MemorySanitizer/bitreverse.ll
@@ -0,0 +1,218 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt < %s -passes=msan -S | FileCheck %s
+;
+; The heuristic handler for llvm.reverse is incorrect because it doesn't
+; reverse the shadow.
+;
+; Forked from llvm/test/CodeGen/X86/bitreverse.ll
+
+target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+declare <2 x i16> @llvm.bitreverse.v2i16(<2 x i16>) readnone
+
+define <2 x i16> @test_bitreverse_v2i16(<2 x i16> %a) nounwind #0 {
+; CHECK-LABEL: define <2 x i16> @test_bitreverse_v2i16(
+; CHECK-SAME: <2 x i16> [[A:%.*]]) #[[ATTR1:[0-9]+]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = load <2 x i16>, ptr @__msan_param_tls, align 8
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> [[A]])
+; CHECK-NEXT:    store <2 x i16> [[TMP1]], ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret <2 x i16> [[B]]
+;
+  %b = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> %a)
+  ret <2 x i16> %b
+}
+
+declare i64 @llvm.bitreverse.i64(i64) readnone
+
+define i64 @test_bitreverse_i64(i64 %a) nounwind #0 {
+; CHECK-LABEL: define i64 @test_bitreverse_i64(
+; CHECK-SAME: i64 [[A:%.*]]) #[[ATTR1]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = load i64, ptr @__msan_param_tls, align 8
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call i64 @llvm.bitreverse.i64(i64 [[A]])
+; CHECK-NEXT:    store i64 [[TMP1]], ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret i64 [[B]]
+;
+  %b = call i64 @llvm.bitreverse.i64(i64 %a)
+  ret i64 %b
+}
+
+declare i32 @llvm.bitreverse.i32(i32) readnone
+
+define i32 @test_bitreverse_i32(i32 %a) nounwind #0 {
+; CHECK-LABEL: define i32 @test_bitreverse_i32(
+; CHECK-SAME: i32 [[A:%.*]]) #[[ATTR1]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = load i32, ptr @__msan_param_tls, align 8
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call i32 @llvm.bitreverse.i32(i32 [[A]])
+; CHECK-NEXT:    store i32 [[TMP1]], ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret i32 [[B]]
+;
+  %b = call i32 @llvm.bitreverse.i32(i32 %a)
+  ret i32 %b
+}
+
+declare i24 @llvm.bitreverse.i24(i24) readnone
+
+define i24 @test_bitreverse_i24(i24 %a) nounwind #0 {
+; CHECK-LABEL: define i24 @test_bitreverse_i24(
+; CHECK-SAME: i24 [[A:%.*]]) #[[ATTR1]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = load i24, ptr @__msan_param_tls, align 8
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call i24 @llvm.bitreverse.i24(i24 [[A]])
+; CHECK-NEXT:    store i24 [[TMP1]], ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret i24 [[B]]
+;
+  %b = call i24 @llvm.bitreverse.i24(i24 %a)
+  ret i24 %b
+}
+
+declare i16 @llvm.bitreverse.i16(i16) readnone
+
+define i16 @test_bitreverse_i16(i16 %a) nounwind #0 {
+; CHECK-LABEL: define i16 @test_bitreverse_i16(
+; CHECK-SAME: i16 [[A:%.*]]) #[[ATTR1]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = load i16, ptr @__msan_param_tls, align 8
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call i16 @llvm.bitreverse.i16(i16 [[A]])
+; CHECK-NEXT:    store i16 [[TMP1]], ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret i16 [[B]]
+;
+  %b = call i16 @llvm.bitreverse.i16(i16 %a)
+  ret i16 %b
+}
+
+declare i8 @llvm.bitreverse.i8(i8) readnone
+
+define i8 @test_bitreverse_i8(i8 %a) #0 {
+; CHECK-LABEL: define i8 @test_bitreverse_i8(
+; CHECK-SAME: i8 [[A:%.*]]) #[[ATTR2:[0-9]+]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = load i8, ptr @__msan_param_tls, align 8
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call i8 @llvm.bitreverse.i8(i8 [[A]])
+; CHECK-NEXT:    store i8 [[TMP1]], ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret i8 [[B]]
+;
+  %b = call i8 @llvm.bitreverse.i8(i8 %a)
+  ret i8 %b
+}
+
+declare i4 @llvm.bitreverse.i4(i4) readnone
+
+define i4 @test_bitreverse_i4(i4 %a) #0 {
+; CHECK-LABEL: define i4 @test_bitreverse_i4(
+; CHECK-SAME: i4 [[A:%.*]]) #[[ATTR2]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = load i4, ptr @__msan_param_tls, align 8
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call i4 @llvm.bitreverse.i4(i4 [[A]])
+; CHECK-NEXT:    store i4 [[TMP1]], ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret i4 [[B]]
+;
+  %b = call i4 @llvm.bitreverse.i4(i4 %a)
+  ret i4 %b
+}
+
+; These tests check that bitreverse(constant) calls are folded
+
+define <2 x i16> @fold_v2i16() #0 {
+; CHECK-LABEL: define <2 x i16> @fold_v2i16(
+; CHECK-SAME: ) #[[ATTR2]] {
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> <i16 15, i16 3840>)
+; CHECK-NEXT:    store <2 x i16> zeroinitializer, ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret <2 x i16> [[B]]
+;
+  %b = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> <i16 15, i16 3840>)
+  ret <2 x i16> %b
+}
+
+define i24 @fold_i24() #0 {
+; CHECK-LABEL: define i24 @fold_i24(
+; CHECK-SAME: ) #[[ATTR2]] {
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call i24 @llvm.bitreverse.i24(i24 4096)
+; CHECK-NEXT:    store i24 0, ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret i24 [[B]]
+;
+  %b = call i24 @llvm.bitreverse.i24(i24 4096)
+  ret i24 %b
+}
+
+define i8 @fold_i8() #0 {
+; CHECK-LABEL: define i8 @fold_i8(
+; CHECK-SAME: ) #[[ATTR2]] {
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call i8 @llvm.bitreverse.i8(i8 15)
+; CHECK-NEXT:    store i8 0, ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret i8 [[B]]
+;
+  %b = call i8 @llvm.bitreverse.i8(i8 15)
+  ret i8 %b
+}
+
+define i4 @fold_i4() #0 {
+; CHECK-LABEL: define i4 @fold_i4(
+; CHECK-SAME: ) #[[ATTR2]] {
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call i4 @llvm.bitreverse.i4(i4 -8)
+; CHECK-NEXT:    store i4 0, ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret i4 [[B]]
+;
+  %b = call i4 @llvm.bitreverse.i4(i4 8)
+  ret i4 %b
+}
+
+; These tests check that bitreverse(bitreverse()) calls are removed
+
+define i8 @identity_i8(i8 %a) #0 {
+; CHECK-LABEL: define i8 @identity_i8(
+; CHECK-SAME: i8 [[A:%.*]]) #[[ATTR2]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = load i8, ptr @__msan_param_tls, align 8
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call i8 @llvm.bitreverse.i8(i8 [[A]])
+; CHECK-NEXT:    [[C:%.*]] = call i8 @llvm.bitreverse.i8(i8 [[B]])
+; CHECK-NEXT:    store i8 [[TMP1]], ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret i8 [[C]]
+;
+  %b = call i8 @llvm.bitreverse.i8(i8 %a)
+  %c = call i8 @llvm.bitreverse.i8(i8 %b)
+  ret i8 %c
+}
+
+define <2 x i16> @identity_v2i16(<2 x i16> %a) #0 {
+; CHECK-LABEL: define <2 x i16> @identity_v2i16(
+; CHECK-SAME: <2 x i16> [[A:%.*]]) #[[ATTR2]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = load <2 x i16>, ptr @__msan_param_tls, align 8
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[B:%.*]] = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> [[A]])
+; CHECK-NEXT:    [[C:%.*]] = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> [[B]])
+; CHECK-NEXT:    store <2 x i16> [[TMP1]], ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret <2 x i16> [[C]]
+;
+  %b = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> %a)
+  %c = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> %b)
+  ret <2 x i16> %c
+}
+
+; Undef tests omitted
+
+; Make sure we don't assert during type legalization promoting a large
+; bitreverse due to the need for a large shift that won't fit in the i8 returned
+; from getShiftAmountTy.
+define i528 @large_promotion(i528 %A) nounwind #0 {
+; CHECK-LABEL: define i528 @large_promotion(
+; CHECK-SAME: i528 [[A:%.*]]) #[[ATTR1]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = load i528, ptr @__msan_param_tls, align 8
+; CHECK-NEXT:    call void @llvm.donothing()
+; CHECK-NEXT:    [[Z:%.*]] = call i528 @llvm.bitreverse.i528(i528 [[A]])
+; CHECK-NEXT:    store i528 [[TMP1]], ptr @__msan_retval_tls, align 8
+; CHECK-NEXT:    ret i528 [[Z]]
+;
+  %Z = call i528 @llvm.bitreverse.i528(i528 %A)
+  ret i528 %Z
+}
+declare i528 @llvm.bitreverse.i528(i528)
+
+attributes #0 = { sanitize_memory }