diff --git a/llvm/include/llvm/CodeGen/AsmPrinter.h b/llvm/include/llvm/CodeGen/AsmPrinter.h
--- a/llvm/include/llvm/CodeGen/AsmPrinter.h
+++ b/llvm/include/llvm/CodeGen/AsmPrinter.h
@@ -286,6 +286,9 @@
   /// Emit a table with all XRay instrumentation points.
   void emitXRayTable();
 
+  DenseMap<const MCSection *, unsigned> PatchableFunctionEntryID;
+  void emitPatchableFunctionEntries();
+
   //===------------------------------------------------------------------===//
   // MachineFunctionPass Implementation.
   //===------------------------------------------------------------------===//
diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -1222,6 +1222,8 @@
   // Emit section containing stack size metadata.
   emitStackSizeSection(*MF);
 
+  emitPatchableFunctionEntries();
+
   if (isVerbose())
     OutStreamer->GetCommentOS() << "-- End function\n";
 
@@ -1660,6 +1662,7 @@
 
 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
   this->MF = &MF;
+  const Function &F = MF.getFunction();
 
   // Get the function symbol.
   if (MAI->needsFunctionDescriptors()) {
@@ -1672,7 +1675,6 @@
     CurrentFnSym =
         OutContext.getOrCreateSymbol("." + CurrentFnDescSym->getName());
 
-    const Function &F = MF.getFunction();
     MCSectionXCOFF *FnEntryPointSec =
         cast<MCSectionXCOFF>(getObjFileLowering().SectionForGlobal(&F, TM));
     // Set the containing csect.
@@ -1685,7 +1687,8 @@
   CurrentFnBegin = nullptr;
   CurExceptionSym = nullptr;
   bool NeedsLocalForSize = MAI->needsLocalForSize();
-  if (needFuncLabelsForEHOrDebugInfo(MF, MMI) || NeedsLocalForSize ||
+  if (F.hasFnAttribute("patchable-function-entry") ||
+      needFuncLabelsForEHOrDebugInfo(MF, MMI) || NeedsLocalForSize ||
       MF.getTarget().Options.EmitStackSizeSection) {
     CurrentFnBegin = createTempSymbol("func_begin");
     if (NeedsLocalForSize)
@@ -3194,6 +3197,38 @@
                                        AlwaysInstrument, &F, Version});
 }
 
+void AsmPrinter::emitPatchableFunctionEntries() {
+  const Function &F = MF->getFunction();
+  if (!F.hasFnAttribute("patchable-function-entry"))
+    return;
+  const unsigned PointerSize = getPointerSize();
+  if (TM.getTargetTriple().isOSBinFormatELF()) {
+    auto Flags = ELF::SHF_WRITE | ELF::SHF_ALLOC;
+    std::string GroupName;
+    if (F.hasComdat()) {
+      Flags |= ELF::SHF_GROUP;
+      GroupName = F.getComdat()->getName();
+    }
+
+    // As of binutils 2.33, GNU as does not support section flag "o". Use
+    // SHF_LINK_ORDER if we are using the integrated assembler.
+    MCSymbolELF *Link = MAI->useIntegratedAssembler()
+                            ? cast<MCSymbolELF>(CurrentFnSym)
+                            : nullptr;
+    if (Link)
+      Flags |= ELF::SHF_LINK_ORDER;
+
+    MCSection *Section = getObjFileLowering().SectionForGlobal(&F, TM);
+    auto R = PatchableFunctionEntryID.try_emplace(
+        Section, PatchableFunctionEntryID.size());
+    OutStreamer->SwitchSection(OutContext.getELFSection(
+        "__patchable_function_entries", ELF::SHT_PROGBITS, Flags, 0, GroupName,
+        R.first->second, Link));
+    EmitAlignment(Align(PointerSize));
+    OutStreamer->EmitSymbolValue(CurrentFnBegin, PointerSize);
+  }
+}
+
 uint16_t AsmPrinter::getDwarfVersion() const {
   return OutStreamer->getContext().getDwarfVersion();
 }
diff --git a/llvm/lib/CodeGen/PatchableFunction.cpp b/llvm/lib/CodeGen/PatchableFunction.cpp
--- a/llvm/lib/CodeGen/PatchableFunction.cpp
+++ b/llvm/lib/CodeGen/PatchableFunction.cpp
@@ -55,6 +55,15 @@
 }
 
 bool PatchableFunction::runOnMachineFunction(MachineFunction &MF) {
+  if (MF.getFunction().hasFnAttribute("patchable-function-entry")) {
+    MachineBasicBlock &FirstMBB = *MF.begin();
+    MachineInstr &FirstMI = *FirstMBB.begin();
+    const TargetInstrInfo *TII = MF.getSubtarget().getInstrInfo();
+    BuildMI(FirstMBB, FirstMI, FirstMI.getDebugLoc(),
+            TII->get(TargetOpcode::PATCHABLE_FUNCTION_ENTER));
+    return true;
+  }
+
   if (!MF.getFunction().hasFnAttribute("patchable-function"))
     return false;
 
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -1851,6 +1851,18 @@
     if (FP != "all" && FP != "non-leaf" && FP != "none")
       CheckFailed("invalid value for 'frame-pointer' attribute: " + FP, V);
   }
+
+  if (Attrs.hasFnAttribute("patchable-function-entry")) {
+    StringRef S0 = Attrs
+                       .getAttribute(AttributeList::FunctionIndex,
+                                     "patchable-function-entry")
+                       .getValueAsString();
+    StringRef S = S0;
+    unsigned N;
+    if (S.getAsInteger(10, N))
+      CheckFailed(
+          "\"patchable-function-entry\" takes an unsigned integer: " + S0, V);
+  }
 }
 
 void Verifier::verifyFunctionMetadata(
diff --git a/llvm/lib/Target/AArch64/AArch64AsmPrinter.cpp b/llvm/lib/Target/AArch64/AArch64AsmPrinter.cpp
--- a/llvm/lib/Target/AArch64/AArch64AsmPrinter.cpp
+++ b/llvm/lib/Target/AArch64/AArch64AsmPrinter.cpp
@@ -243,6 +243,18 @@
 
 void AArch64AsmPrinter::LowerPATCHABLE_FUNCTION_ENTER(const MachineInstr &MI)
 {
+  const Function &F = MF->getFunction();
+  if (F.hasFnAttribute("patchable-function-entry")) {
+    unsigned Num;
+    if (F.getFnAttribute("patchable-function-entry")
+            .getValueAsString()
+            .getAsInteger(10, Num))
+      return;
+    for (; Num; --Num)
+      EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::HINT).addImm(0));
+    return;
+  }
+
   EmitSled(MI, SledKind::FUNCTION_ENTER);
 }
 
diff --git a/llvm/test/CodeGen/AArch64/patchable-function-entry.ll b/llvm/test/CodeGen/AArch64/patchable-function-entry.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/AArch64/patchable-function-entry.ll
@@ -0,0 +1,55 @@
+; RUN: llc -mtriple=aarch64 %s -o - | FileCheck --check-prefixes=CHECK,NOFSECT %s
+; RUN: llc -mtriple=aarch64 -function-sections %s -o - | FileCheck --check-prefixes=CHECK,FSECT %s
+; RUN: llc -mtriple=aarch64 -no-integrated-as %s -o - | FileCheck --check-prefix=NOLINK %s
+
+; NOLINK-NOT: "awo"
+
+define i32 @f0() "patchable-function-entry"="0" {
+; CHECK-LABEL: f0:
+; CHECK-NEXT: .Lfunc_begin0:
+; CHECK-NOT:   nop
+; CHECK:       mov w0, wzr
+; CHECK:       .section __patchable_function_entries,"awo",@progbits,f0,unique,0
+; CHECK-NEXT:  .p2align 3
+; CHECK-NEXT:  .xword .Lfunc_begin0
+  ret i32 0
+}
+
+define i32 @f1() "patchable-function-entry"="1" {
+; CHECK-LABEL: f1:
+; CHECK-NEXT: .Lfunc_begin1:
+; CHECK:       nop
+; CHECK-NEXT:  mov w0, wzr
+; NOFSECT:     .section __patchable_function_entries,"awo",@progbits,f0,unique,0
+; FSECT:       .section __patchable_function_entries,"awo",@progbits,f1,unique,1
+; CHECK-NEXT:  .p2align 3
+; CHECK-NEXT:  .xword .Lfunc_begin1
+  ret i32 0
+}
+
+$f3 = comdat any
+define void @f3() "patchable-function-entry"="3" comdat {
+; CHECK-LABEL: f3:
+; CHECK-NEXT: .Lfunc_begin2:
+; CHECK-COUNT-3: nop
+; CHECK-NEXT:  ret
+; NOFSECT:     .section __patchable_function_entries,"aGwo",@progbits,f3,comdat,f3,unique,1
+; FSECT:       .section __patchable_function_entries,"aGwo",@progbits,f3,comdat,f3,unique,2
+; CHECK-NEXT:  .p2align 3
+; CHECK-NEXT:  .xword .Lfunc_begin2
+  ret void
+}
+
+$f5 = comdat any
+define void @f5() "patchable-function-entry"="5" comdat {
+; CHECK-LABEL: f5:
+; CHECK-NEXT: .Lfunc_begin3:
+; CHECK-COUNT-5: nop
+; CHECK-NEXT:  sub sp, sp, #16
+; NOFSECT      .section __patchable_function_entries,"aGwo",@progbits,f5,comdat,f5,unique,2
+; FSECT:       .section __patchable_function_entries,"aGwo",@progbits,f5,comdat,f5,unique,3
+; CHECK:       .p2align 3
+; CHECK-NEXT:  .xword .Lfunc_begin3
+  %frame = alloca i8, i32 16
+  ret void
+}
diff --git a/llvm/test/Verifier/invalid-patchable-function-entry.ll b/llvm/test/Verifier/invalid-patchable-function-entry.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Verifier/invalid-patchable-function-entry.ll
@@ -0,0 +1,11 @@
+; RUN: not llvm-as %s -o /dev/null 2>&1 | FileCheck %s
+
+; CHECK: "patchable-function-entry" takes an unsigned integer:
+; CHECK: "patchable-function-entry" takes an unsigned integer: a
+; CHECK: "patchable-function-entry" takes an unsigned integer: -1
+; CHECK: "patchable-function-entry" takes an unsigned integer: 3,
+
+define void @f() "patchable-function-entry" { ret void }
+define void @fa() "patchable-function-entry"="a" { ret void }
+define void @f_1() "patchable-function-entry"="-1" { ret void }
+define void @f3comma() "patchable-function-entry"="3," { ret void }