diff --git a/llvm/lib/Analysis/MemoryLocation.cpp b/llvm/lib/Analysis/MemoryLocation.cpp
--- a/llvm/lib/Analysis/MemoryLocation.cpp
+++ b/llvm/lib/Analysis/MemoryLocation.cpp
@@ -120,20 +120,6 @@
 
 Optional<MemoryLocation>
 MemoryLocation::getForDest(const CallBase *CB, const TargetLibraryInfo &TLI) {
-  if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(CB)) {
-    if (auto *MemInst = dyn_cast<AnyMemIntrinsic>(CB))
-      return getForDest(MemInst);
-
-    switch (II->getIntrinsicID()) {
-    default:
-      return None;
-    case Intrinsic::init_trampoline:
-      return MemoryLocation::getForArgument(CB, 0, TLI);
-    case Intrinsic::masked_store:
-      return MemoryLocation::getForArgument(CB, 1, TLI);
-    }
-  }
-
   if (!CB->onlyAccessesArgMemory())
     return None;
 
diff --git a/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp b/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
--- a/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
+++ b/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
@@ -182,33 +182,19 @@
   if (StoreInst *SI = dyn_cast<StoreInst>(I))
     return SI->isUnordered();
 
-  if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) {
-    switch (II->getIntrinsicID()) {
-    default: llvm_unreachable("Does not have LocForWrite");
-    case Intrinsic::lifetime_end:
-      // Never remove dead lifetime_end's, e.g. because it is followed by a
-      // free.
+  // Note: only get here for calls with analyzable writes.
+  if (auto *CB = dyn_cast<CallBase>(I)) {
+    // Don't remove volatile memory intrinsics.
+    if (auto *MI = dyn_cast<MemIntrinsic>(CB))
+      return !MI->isVolatile();
+
+    // Never remove dead lifetime intrinsics, e.g. because they are followed by
+    // a free.
+    if (CB->isLifetimeStartOrEnd())
       return false;
-    case Intrinsic::init_trampoline:
-      // Always safe to remove init_trampoline.
-      return true;
-    case Intrinsic::memset:
-    case Intrinsic::memmove:
-    case Intrinsic::memcpy:
-    case Intrinsic::memcpy_inline:
-      // Don't remove volatile memory intrinsics.
-      return !cast<MemIntrinsic>(II)->isVolatile();
-    case Intrinsic::memcpy_element_unordered_atomic:
-    case Intrinsic::memmove_element_unordered_atomic:
-    case Intrinsic::memset_element_unordered_atomic:
-    case Intrinsic::masked_store:
-      return true;
-    }
-  }
 
-  // note: only get here for calls with analyzable writes.
-  if (auto *CB = dyn_cast<CallBase>(I))
     return CB->use_empty() && CB->willReturn() && CB->doesNotThrow();
+  }
 
   return false;
 }
diff --git a/llvm/test/Transforms/DeadStoreElimination/invariant.start.ll b/llvm/test/Transforms/DeadStoreElimination/invariant.start.ll
--- a/llvm/test/Transforms/DeadStoreElimination/invariant.start.ll
+++ b/llvm/test/Transforms/DeadStoreElimination/invariant.start.ll
@@ -4,13 +4,13 @@
 
 declare {}* @llvm.invariant.start.p0i8(i64, i8* nocapture) nounwind readonly
 
-; We cannot remove the store 1 to %p.
-; FIXME: By the semantics of invariant.start, the store 3 to p is unreachable.
+; We could remove either store here. The first store is dead in the
+; conventional sense, because there is a later killing store. The second store
+; is undefined behavior by the semantics of invariant.start, and as such
+; unreachable.
 define void @test(i8 *%p) {
 ; CHECK-LABEL: @test(
-; CHECK-NEXT:    store i8 1, i8* [[P:%.*]], align 4
-; CHECK-NEXT:    [[I:%.*]] = call {}* @llvm.invariant.start.p0i8(i64 1, i8* [[P]])
-; CHECK-NEXT:    store i8 3, i8* [[P]], align 4
+; CHECK-NEXT:    store i8 3, i8* [[P:%.*]], align 4
 ; CHECK-NEXT:    ret void
 ;
   store i8 1, i8* %p, align 4
diff --git a/llvm/test/Transforms/DeadStoreElimination/simple.ll b/llvm/test/Transforms/DeadStoreElimination/simple.ll
--- a/llvm/test/Transforms/DeadStoreElimination/simple.ll
+++ b/llvm/test/Transforms/DeadStoreElimination/simple.ll
@@ -194,12 +194,9 @@
   ret void
 }
 
-; TODO: Specialized store intrinsics should be removed if dead.
+; Specialized store intrinsics should be removed if dead.
 define void @test_matrix_store(i64 %stride) {
 ; CHECK-LABEL: @test_matrix_store(
-; CHECK-NEXT:    [[A:%.*]] = alloca [6 x float], align 4
-; CHECK-NEXT:    [[CAST:%.*]] = bitcast [6 x float]* [[A]] to float*
-; CHECK-NEXT:    call void @llvm.matrix.column.major.store.v6f32.i64(<6 x float> zeroinitializer, float* [[CAST]], i64 [[STRIDE:%.*]], i1 false, i32 3, i32 2)
 ; CHECK-NEXT:    ret void
 ;
   %a = alloca [6 x float]