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
@@ -1875,8 +1875,20 @@
           // We are searching for the definition of the store's destination.
           // So, if that is the same definition as the load, then this is a
           // noop. Otherwise, fail.
-          if (LoadAccess != Current)
+          if (LoadAccess != Current) {
+            // This is a potentially clobbering store, but it writes the same
+            // value, so we can safely ignore it if alignment is as expected.
+            if (auto *CurrentDef = dyn_cast<MemoryDef>(Current))
+              if (auto *CurrentStoreI =
+                      dyn_cast_or_null<StoreInst>(CurrentDef->getMemoryInst()))
+                // Check alignment to ensure load or store does not access at an
+                // offset.
+                if (CurrentStoreI->getOperand(0) == LoadI &&
+                    std::min(CurrentStoreI->getAlign(), LoadI->getAlign()) >=
+                        DL.getTypeStoreSize(LoadI->getType()))
+                  continue;
             return false;
+          }
         }
         return true;
       }
diff --git a/llvm/test/Transforms/DeadStoreElimination/noop-stores.ll b/llvm/test/Transforms/DeadStoreElimination/noop-stores.ll
--- a/llvm/test/Transforms/DeadStoreElimination/noop-stores.ll
+++ b/llvm/test/Transforms/DeadStoreElimination/noop-stores.ll
@@ -673,3 +673,92 @@
 if.end:
   ret i8* %3
 }
+
+define void @store_same_i32_to_mayalias_loc(i32* %q, i32* %p) {
+; CHECK-LABEL: @store_same_i32_to_mayalias_loc(
+; CHECK-NEXT:    [[V:%.*]] = load i32, i32* [[P:%.*]], align 4
+; CHECK-NEXT:    store i32 [[V]], i32* [[Q:%.*]], align 4
+; CHECK-NEXT:    ret void
+;
+  %v = load i32, i32* %p, align 4
+  store i32 %v, i32* %q, align 4
+  store i32 %v, i32* %p, align 4
+  ret void
+}
+
+define void @store_same_i32_to_mayalias_loc_unalign(i32* %q, i32* %p) {
+; CHECK-LABEL: @store_same_i32_to_mayalias_loc_unalign(
+; CHECK-NEXT:    [[V:%.*]] = load i32, i32* [[P:%.*]], align 1
+; CHECK-NEXT:    store i32 [[V]], i32* [[Q:%.*]], align 1
+; CHECK-NEXT:    store i32 [[V]], i32* [[P]], align 1
+; CHECK-NEXT:    ret void
+;
+  %v = load i32, i32* %p, align 1
+  store i32 %v, i32* %q, align 1
+  store i32 %v, i32* %p, align 1
+  ret void
+}
+
+define void @store_same_i12_to_mayalias_loc(i12* %q, i12* %p) {
+; CHECK-LABEL: @store_same_i12_to_mayalias_loc(
+; CHECK-NEXT:    [[V:%.*]] = load i12, i12* [[P:%.*]], align 2
+; CHECK-NEXT:    store i12 [[V]], i12* [[Q:%.*]], align 2
+; CHECK-NEXT:    ret void
+;
+  %v = load i12, i12* %p, align 2
+  store i12 %v, i12* %q, align 2
+  store i12 %v, i12* %p, align 2
+  ret void
+}
+
+define void @store_same_ptr_to_mayalias_loc(i32** %q, i32** %p) {
+; CHECK-LABEL: @store_same_ptr_to_mayalias_loc(
+; CHECK-NEXT:    [[V:%.*]] = load i32*, i32** [[P:%.*]], align 8
+; CHECK-NEXT:    store i32* [[V]], i32** [[Q:%.*]], align 8
+; CHECK-NEXT:    ret void
+;
+  %v = load i32*, i32** %p, align 8
+  store i32* %v, i32** %q, align 8
+  store i32* %v, i32** %p, align 8
+  ret void
+}
+
+define void @store_same_i32_to_mayalias_loc_inconsistent_align(i32* %q, i32* %p) {
+; CHECK-LABEL: @store_same_i32_to_mayalias_loc_inconsistent_align(
+; CHECK-NEXT:    [[V:%.*]] = load i32, i32* [[P:%.*]], align 2
+; CHECK-NEXT:    store i32 [[V]], i32* [[Q:%.*]], align 4
+; CHECK-NEXT:    store i32 [[V]], i32* [[P]], align 4
+; CHECK-NEXT:    ret void
+;
+  %v = load i32, i32* %p, align 2
+  store i32 %v, i32* %q, align 4
+  store i32 %v, i32* %p, align 4
+  ret void
+}
+
+define void @do_not_crash_on_liveonentrydef(i1 %c, i8* %p, i8* noalias %q) {
+; CHECK-LABEL: @do_not_crash_on_liveonentrydef(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br i1 [[C:%.*]], label [[IF:%.*]], label [[JOIN:%.*]]
+; CHECK:       if:
+; CHECK-NEXT:    store i8 0, i8* [[Q:%.*]], align 1
+; CHECK-NEXT:    br label [[JOIN]]
+; CHECK:       join:
+; CHECK-NEXT:    [[V:%.*]] = load i8, i8* [[Q]], align 1
+; CHECK-NEXT:    store i8 0, i8* [[P:%.*]], align 1
+; CHECK-NEXT:    store i8 [[V]], i8* [[Q]], align 1
+; CHECK-NEXT:    ret void
+;
+entry:
+  br i1 %c, label %if, label %join
+
+if:
+  store i8 0, i8* %q, align 1
+  br label %join
+
+join:
+  %v = load i8, i8* %q, align 1
+  store i8 0, i8* %p, align 1
+  store i8 %v, i8* %q, align 1
+  ret void
+}
diff --git a/llvm/test/Transforms/DeadStoreElimination/stores-of-existing-values.ll b/llvm/test/Transforms/DeadStoreElimination/stores-of-existing-values.ll
--- a/llvm/test/Transforms/DeadStoreElimination/stores-of-existing-values.ll
+++ b/llvm/test/Transforms/DeadStoreElimination/stores-of-existing-values.ll
@@ -612,12 +612,10 @@
 ; CHECK-LABEL: @pr49927(
 ; CHECK-NEXT:    [[V:%.*]] = load i32, i32* [[P:%.*]], align 4
 ; CHECK-NEXT:    store i32 [[V]], i32* [[Q:%.*]], align 4
-; CHECK-NEXT:    store i32 [[V]], i32* [[P]], align 4
 ; CHECK-NEXT:    ret void
 ;
   %v = load i32, i32* %p, align 4
   store i32 %v, i32* %q, align 4
-  ; FIXME: this store can be eliminated
   store i32 %v, i32* %p, align 4
   ret void
 }