diff --git a/clang/test/CodeGen/ms-mixed-ptr-sizes.c b/clang/test/CodeGen/ms-mixed-ptr-sizes.c
index 294a8910e13e30..ececa42a4c4dd8 100644
--- a/clang/test/CodeGen/ms-mixed-ptr-sizes.c
+++ b/clang/test/CodeGen/ms-mixed-ptr-sizes.c
@@ -7,32 +7,32 @@ struct Foo {
 };
 void use_foo(struct Foo *f);
 void test_sign_ext(struct Foo *f, int * __ptr32 __sptr i) {
-// X64-LABEL: define dso_local void @test_sign_ext({{.*}}i32 addrspace(270)* writeonly %i)
-// X86-LABEL: define dso_local void @test_sign_ext(%struct.Foo* %f, i32* writeonly %i)
+// X64-LABEL: define dso_local void @test_sign_ext({{.*}}i32 addrspace(270)* %i)
+// X86-LABEL: define dso_local void @test_sign_ext(%struct.Foo* %f, i32* %i)
 // X64: %{{.+}} = addrspacecast i32 addrspace(270)* %i to i32*
 // X86: %{{.+}} = addrspacecast i32* %i to i32 addrspace(272)*
   f->p64 = i;
   use_foo(f);
 }
 void test_zero_ext(struct Foo *f, int * __ptr32 __uptr i) {
-// X64-LABEL: define dso_local void @test_zero_ext({{.*}}i32 addrspace(271)* writeonly %i)
-// X86-LABEL: define dso_local void @test_zero_ext({{.*}}i32 addrspace(271)* writeonly %i)
+// X64-LABEL: define dso_local void @test_zero_ext({{.*}}i32 addrspace(271)* %i)
+// X86-LABEL: define dso_local void @test_zero_ext({{.*}}i32 addrspace(271)* %i)
 // X64: %{{.+}} = addrspacecast i32 addrspace(271)* %i to i32*
 // X86: %{{.+}} = addrspacecast i32 addrspace(271)* %i to i32 addrspace(272)*
   f->p64 = i;
   use_foo(f);
 }
 void test_trunc(struct Foo *f, int * __ptr64 i) {
-// X64-LABEL: define dso_local void @test_trunc(%struct.Foo* %f, i32* writeonly %i)
-// X86-LABEL: define dso_local void @test_trunc({{.*}}i32 addrspace(272)* writeonly %i)
+// X64-LABEL: define dso_local void @test_trunc(%struct.Foo* %f, i32* %i)
+// X86-LABEL: define dso_local void @test_trunc({{.*}}i32 addrspace(272)* %i)
 // X64: %{{.+}} = addrspacecast i32* %i to i32 addrspace(270)*
 // X86: %{{.+}} = addrspacecast i32 addrspace(272)* %i to i32*
   f->p32 = i;
   use_foo(f);
 }
 void test_noop(struct Foo *f, int * __ptr32 i) {
-// X64-LABEL: define dso_local void @test_noop({{.*}}i32 addrspace(270)* writeonly %i)
-// X86-LABEL: define dso_local void @test_noop({{.*}}i32* writeonly %i)
+// X64-LABEL: define dso_local void @test_noop({{.*}}i32 addrspace(270)* %i)
+// X86-LABEL: define dso_local void @test_noop({{.*}}i32* %i)
 // X64-NOT: addrspacecast
 // X86-NOT: addrspacecast
   f->p32 = i;
@@ -40,8 +40,8 @@ void test_noop(struct Foo *f, int * __ptr32 i) {
 }
 
 void test_other(struct Foo *f, __attribute__((address_space(10))) int *i) {
-// X64-LABEL: define dso_local void @test_other({{.*}}i32 addrspace(10)* writeonly %i)
-// X86-LABEL: define dso_local void @test_other({{.*}}i32 addrspace(10)* writeonly %i)
+// X64-LABEL: define dso_local void @test_other({{.*}}i32 addrspace(10)* %i)
+// X86-LABEL: define dso_local void @test_other({{.*}}i32 addrspace(10)* %i)
 // X64: %{{.+}} = addrspacecast i32 addrspace(10)* %i to i32 addrspace(270)*
 // X86: %{{.+}} = addrspacecast i32 addrspace(10)* %i to i32*
   f->p32 = (int * __ptr32)i;
diff --git a/llvm/lib/Transforms/IPO/FunctionAttrs.cpp b/llvm/lib/Transforms/IPO/FunctionAttrs.cpp
index 1ad0055b563824..2cee9c0b4766a3 100644
--- a/llvm/lib/Transforms/IPO/FunctionAttrs.cpp
+++ b/llvm/lib/Transforms/IPO/FunctionAttrs.cpp
@@ -769,6 +769,10 @@ determinePointerAccessAttrs(Argument *A,
       break;
 
     case Instruction::Store:
+      if (cast<StoreInst>(I)->getValueOperand() == *U)
+        // untrackable capture
+        return Attribute::None;
+
       // A volatile store has side effects beyond what writeonly can be relied
       // upon.
       if (cast<StoreInst>(I)->isVolatile())
diff --git a/llvm/test/Feature/OperandBundles/pr26510.ll b/llvm/test/Feature/OperandBundles/pr26510.ll
index 878628627b056d..1877f35a400678 100644
--- a/llvm/test/Feature/OperandBundles/pr26510.ll
+++ b/llvm/test/Feature/OperandBundles/pr26510.ll
@@ -10,7 +10,7 @@
 
 declare void @foo() readnone
 
-; CHECK-LABEL: define i8* @test(i8* writeonly %p)
+; CHECK-LABEL: define i8* @test(i8* %p)
 ; CHECK:   %a = alloca i8*, align 8
 ; CHECK:   store i8* %p, i8** %a, align 8
 ; CHECK:   call void @foo() [ "abc"(i8** %a) ]
diff --git a/llvm/test/Transforms/Coroutines/coro-async.ll b/llvm/test/Transforms/Coroutines/coro-async.ll
index 86d95c33665490..151573fe229259 100644
--- a/llvm/test/Transforms/Coroutines/coro-async.ll
+++ b/llvm/test/Transforms/Coroutines/coro-async.ll
@@ -256,7 +256,7 @@ entry:
   unreachable
 }
 
-; CHECK-LABEL: define swiftcc void @my_async_function2(%async.task* %task, %async.actor* %actor, i8* writeonly %async.ctxt)
+; CHECK-LABEL: define swiftcc void @my_async_function2(%async.task* %task, %async.actor* %actor, i8* %async.ctxt)
 ; CHECK-SAME: #[[FRAMEPOINTER:[0-9]+]]
 ; CHECK-SAME: !dbg ![[SP3:[0-9]+]]
 ; CHECK: store i8* %async.ctxt,
@@ -269,7 +269,7 @@ entry:
 ; CHECK: tail call swiftcc void @asyncSuspend(i8* [[CALLEE_CTXT]], %async.task* %task, %async.actor* %actor)
 ; CHECK: ret void
 
-; CHECK-LABEL: define internal swiftcc void @my_async_function2.resume.0(i8* writeonly %0, i8* nocapture readnone %1, i8* nocapture readonly %2)
+; CHECK-LABEL: define internal swiftcc void @my_async_function2.resume.0(i8* %0, i8* nocapture readnone %1, i8* nocapture readonly %2)
 ; CHECK-SAME: #[[FRAMEPOINTER]]
 ; CHECK-SAME: !dbg ![[SP4:[0-9]+]]
 ; CHECK: [[CALLEE_CTXT_ADDR:%.*]] = bitcast i8* %2 to i8**
diff --git a/llvm/test/Transforms/FunctionAttrs/2009-01-02-LocalStores.ll b/llvm/test/Transforms/FunctionAttrs/2009-01-02-LocalStores.ll
index e493787f93b333..435f7810fbde6c 100644
--- a/llvm/test/Transforms/FunctionAttrs/2009-01-02-LocalStores.ll
+++ b/llvm/test/Transforms/FunctionAttrs/2009-01-02-LocalStores.ll
@@ -7,7 +7,7 @@ define i32* @a(i32** %p) {
 	ret i32* %tmp
 }
 
-; CHECK: define i32* @b(i32* writeonly %q)
+; CHECK: define i32* @b(i32* %q)
 define i32* @b(i32 *%q) {
 	%mem = alloca i32*
 	store i32* %q, i32** %mem
diff --git a/llvm/test/Transforms/FunctionAttrs/nocapture.ll b/llvm/test/Transforms/FunctionAttrs/nocapture.ll
index 5fc33e5c8c1922..2042f3e0d724f0 100644
--- a/llvm/test/Transforms/FunctionAttrs/nocapture.ll
+++ b/llvm/test/Transforms/FunctionAttrs/nocapture.ll
@@ -8,7 +8,7 @@ define i32* @c1(i32* %q) {
 	ret i32* %q
 }
 
-; FNATTR: define void @c2(i32* writeonly %q)
+; FNATTR: define void @c2(i32* %q)
 ; It would also be acceptable to mark %q as readnone. Update @c3 too.
 define void @c2(i32* %q) {
 	store i32* %q, i32** @g
@@ -268,7 +268,7 @@ entry:
 }
 
 @g3 = global i8* null
-; FNATTR: define void @captureStrip(i8* writeonly %p)
+; FNATTR: define void @captureStrip(i8* %p)
 define void @captureStrip(i8* %p) {
   %b = call i8* @llvm.strip.invariant.group.p0i8(i8* %p)
   store i8* %b, i8** @g3
diff --git a/llvm/test/Transforms/FunctionAttrs/readattrs.ll b/llvm/test/Transforms/FunctionAttrs/readattrs.ll
index e300b85cf9207b..59f58bdee9aa1f 100644
--- a/llvm/test/Transforms/FunctionAttrs/readattrs.ll
+++ b/llvm/test/Transforms/FunctionAttrs/readattrs.ll
@@ -34,7 +34,7 @@ define void @test4_2(i8* %p) {
   ret void
 }
 
-; CHECK: define void @test5(i8** nocapture writeonly %p, i8* writeonly %q)
+; CHECK: define void @test5(i8** nocapture writeonly %p, i8* %q)
 ; Missed optz'n: we could make %q readnone, but don't break test6!
 define void @test5(i8** %p, i8* %q) {
   store i8* %q, i8** %p
@@ -42,7 +42,7 @@ define void @test5(i8** %p, i8* %q) {
 }
 
 declare void @test6_1()
-; CHECK: define void @test6_2(i8** nocapture writeonly %p, i8* writeonly %q)
+; CHECK: define void @test6_2(i8** nocapture writeonly %p, i8* %q)
 ; This is not a missed optz'n.
 define void @test6_2(i8** %p, i8* %q) {
   store i8* %q, i8** %p
diff --git a/llvm/test/Transforms/FunctionAttrs/writeonly.ll b/llvm/test/Transforms/FunctionAttrs/writeonly.ll
index ac3b5ffcca51b3..fb391111b301b8 100644
--- a/llvm/test/Transforms/FunctionAttrs/writeonly.ll
+++ b/llvm/test/Transforms/FunctionAttrs/writeonly.ll
@@ -31,6 +31,15 @@ define void @test_store(i8* %p) {
   ret void
 }
 
+@G = external global i8*
+; CHECK: define i8 @test_store_capture(i8* %p)
+define i8 @test_store_capture(i8* %p) {
+  store i8* %p, i8** @G
+  %p2 = load i8*, i8** @G
+  %v = load i8, i8* %p2
+  ret i8 %v
+}
+
 ; CHECK: define void @test_addressing(i8* nocapture writeonly %p)
 define void @test_addressing(i8* %p) {
   %gep = getelementptr i8, i8* %p, i64 8