diff --git a/clang-tools-extra/clangd/HeuristicResolver.cpp b/clang-tools-extra/clangd/HeuristicResolver.cpp
index 3c147b6b582bf0..26d54200eeffd2 100644
--- a/clang-tools-extra/clangd/HeuristicResolver.cpp
+++ b/clang-tools-extra/clangd/HeuristicResolver.cpp
@@ -16,6 +16,80 @@
 namespace clang {
 namespace clangd {
 
+namespace {
+
+// Helper class for implementing HeuristicResolver.
+// Unlike HeuristicResolver which is a long-lived class,
+// a new instance of this class is created for every external
+// call into a HeuristicResolver operation. That allows this
+// class to store state that's local to such a top-level call,
+// particularly "recursion protection sets" that keep track of
+// nodes that have already been seen to avoid infinite recursion.
+class HeuristicResolverImpl {
+public:
+  HeuristicResolverImpl(ASTContext &Ctx) : Ctx(Ctx) {}
+
+  // These functions match the public interface of HeuristicResolver
+  // (but aren't const since they may modify the recursion protection sets).
+  std::vector<const NamedDecl *>
+  resolveMemberExpr(const CXXDependentScopeMemberExpr *ME);
+  std::vector<const NamedDecl *>
+  resolveDeclRefExpr(const DependentScopeDeclRefExpr *RE);
+  std::vector<const NamedDecl *> resolveTypeOfCallExpr(const CallExpr *CE);
+  std::vector<const NamedDecl *> resolveCalleeOfCallExpr(const CallExpr *CE);
+  std::vector<const NamedDecl *>
+  resolveUsingValueDecl(const UnresolvedUsingValueDecl *UUVD);
+  std::vector<const NamedDecl *>
+  resolveDependentNameType(const DependentNameType *DNT);
+  std::vector<const NamedDecl *> resolveTemplateSpecializationType(
+      const DependentTemplateSpecializationType *DTST);
+  const Type *resolveNestedNameSpecifierToType(const NestedNameSpecifier *NNS);
+  const Type *getPointeeType(const Type *T);
+
+private:
+  ASTContext &Ctx;
+
+  // Recursion protection sets
+  llvm::SmallSet<const DependentNameType *, 4> SeenDependentNameTypes;
+
+  // Given a tag-decl type and a member name, heuristically resolve the
+  // name to one or more declarations.
+  // The current heuristic is simply to look up the name in the primary
+  // template. This is a heuristic because the template could potentially
+  // have specializations that declare different members.
+  // Multiple declarations could be returned if the name is overloaded
+  // (e.g. an overloaded method in the primary template).
+  // This heuristic will give the desired answer in many cases, e.g.
+  // for a call to vector<T>::size().
+  std::vector<const NamedDecl *>
+  resolveDependentMember(const Type *T, DeclarationName Name,
+                         llvm::function_ref<bool(const NamedDecl *ND)> Filter);
+
+  // Try to heuristically resolve the type of a possibly-dependent expression
+  // `E`.
+  const Type *resolveExprToType(const Expr *E);
+  std::vector<const NamedDecl *> resolveExprToDecls(const Expr *E);
+
+  // Helper function for HeuristicResolver::resolveDependentMember()
+  // which takes a possibly-dependent type `T` and heuristically
+  // resolves it to a CXXRecordDecl in which we can try name lookup.
+  CXXRecordDecl *resolveTypeToRecordDecl(const Type *T);
+
+  // This is a reimplementation of CXXRecordDecl::lookupDependentName()
+  // so that the implementation can call into other HeuristicResolver helpers.
+  // FIXME: Once HeuristicResolver is upstreamed to the clang libraries
+  // (https://github.com/clangd/clangd/discussions/1662),
+  // CXXRecordDecl::lookupDepenedentName() can be removed, and its call sites
+  // can be modified to benefit from the more comprehensive heuristics offered
+  // by HeuristicResolver instead.
+  std::vector<const NamedDecl *>
+  lookupDependentName(CXXRecordDecl *RD, DeclarationName Name,
+                      llvm::function_ref<bool(const NamedDecl *ND)> Filter);
+  bool findOrdinaryMemberInDependentClasses(const CXXBaseSpecifier *Specifier,
+                                            CXXBasePath &Path,
+                                            DeclarationName Name);
+};
+
 // Convenience lambdas for use as the 'Filter' parameter of
 // HeuristicResolver::resolveDependentMember().
 const auto NoFilter = [](const NamedDecl *D) { return true; };
@@ -31,8 +105,6 @@ const auto TemplateFilter = [](const NamedDecl *D) {
   return isa<TemplateDecl>(D);
 };
 
-namespace {
-
 const Type *resolveDeclsToType(const std::vector<const NamedDecl *> &Decls,
                                ASTContext &Ctx) {
   if (Decls.size() != 1) // Names an overload set -- just bail.
@@ -46,12 +118,10 @@ const Type *resolveDeclsToType(const std::vector<const NamedDecl *> &Decls,
   return nullptr;
 }
 
-} // namespace
-
 // Helper function for HeuristicResolver::resolveDependentMember()
 // which takes a possibly-dependent type `T` and heuristically
 // resolves it to a CXXRecordDecl in which we can try name lookup.
-CXXRecordDecl *HeuristicResolver::resolveTypeToRecordDecl(const Type *T) const {
+CXXRecordDecl *HeuristicResolverImpl::resolveTypeToRecordDecl(const Type *T) {
   assert(T);
 
   // Unwrap type sugar such as type aliases.
@@ -84,7 +154,7 @@ CXXRecordDecl *HeuristicResolver::resolveTypeToRecordDecl(const Type *T) const {
   return TD->getTemplatedDecl();
 }
 
-const Type *HeuristicResolver::getPointeeType(const Type *T) const {
+const Type *HeuristicResolverImpl::getPointeeType(const Type *T) {
   if (!T)
     return nullptr;
 
@@ -117,8 +187,8 @@ const Type *HeuristicResolver::getPointeeType(const Type *T) const {
   return FirstArg.getAsType().getTypePtrOrNull();
 }
 
-std::vector<const NamedDecl *> HeuristicResolver::resolveMemberExpr(
-    const CXXDependentScopeMemberExpr *ME) const {
+std::vector<const NamedDecl *> HeuristicResolverImpl::resolveMemberExpr(
+    const CXXDependentScopeMemberExpr *ME) {
   // If the expression has a qualifier, try resolving the member inside the
   // qualifier's type.
   // Note that we cannot use a NonStaticFilter in either case, for a couple
@@ -164,14 +234,14 @@ std::vector<const NamedDecl *> HeuristicResolver::resolveMemberExpr(
   return resolveDependentMember(BaseType, ME->getMember(), NoFilter);
 }
 
-std::vector<const NamedDecl *> HeuristicResolver::resolveDeclRefExpr(
-    const DependentScopeDeclRefExpr *RE) const {
+std::vector<const NamedDecl *>
+HeuristicResolverImpl::resolveDeclRefExpr(const DependentScopeDeclRefExpr *RE) {
   return resolveDependentMember(RE->getQualifier()->getAsType(),
                                 RE->getDeclName(), StaticFilter);
 }
 
 std::vector<const NamedDecl *>
-HeuristicResolver::resolveTypeOfCallExpr(const CallExpr *CE) const {
+HeuristicResolverImpl::resolveTypeOfCallExpr(const CallExpr *CE) {
   const auto *CalleeType = resolveExprToType(CE->getCallee());
   if (!CalleeType)
     return {};
@@ -187,7 +257,7 @@ HeuristicResolver::resolveTypeOfCallExpr(const CallExpr *CE) const {
 }
 
 std::vector<const NamedDecl *>
-HeuristicResolver::resolveCalleeOfCallExpr(const CallExpr *CE) const {
+HeuristicResolverImpl::resolveCalleeOfCallExpr(const CallExpr *CE) {
   if (const auto *ND = dyn_cast_or_null<NamedDecl>(CE->getCalleeDecl())) {
     return {ND};
   }
@@ -195,29 +265,31 @@ HeuristicResolver::resolveCalleeOfCallExpr(const CallExpr *CE) const {
   return resolveExprToDecls(CE->getCallee());
 }
 
-std::vector<const NamedDecl *> HeuristicResolver::resolveUsingValueDecl(
-    const UnresolvedUsingValueDecl *UUVD) const {
+std::vector<const NamedDecl *> HeuristicResolverImpl::resolveUsingValueDecl(
+    const UnresolvedUsingValueDecl *UUVD) {
   return resolveDependentMember(UUVD->getQualifier()->getAsType(),
                                 UUVD->getNameInfo().getName(), ValueFilter);
 }
 
-std::vector<const NamedDecl *> HeuristicResolver::resolveDependentNameType(
-    const DependentNameType *DNT) const {
+std::vector<const NamedDecl *>
+HeuristicResolverImpl::resolveDependentNameType(const DependentNameType *DNT) {
+  if (auto [_, inserted] = SeenDependentNameTypes.insert(DNT); !inserted)
+    return {};
   return resolveDependentMember(
       resolveNestedNameSpecifierToType(DNT->getQualifier()),
       DNT->getIdentifier(), TypeFilter);
 }
 
 std::vector<const NamedDecl *>
-HeuristicResolver::resolveTemplateSpecializationType(
-    const DependentTemplateSpecializationType *DTST) const {
+HeuristicResolverImpl::resolveTemplateSpecializationType(
+    const DependentTemplateSpecializationType *DTST) {
   return resolveDependentMember(
       resolveNestedNameSpecifierToType(DTST->getQualifier()),
       DTST->getIdentifier(), TemplateFilter);
 }
 
 std::vector<const NamedDecl *>
-HeuristicResolver::resolveExprToDecls(const Expr *E) const {
+HeuristicResolverImpl::resolveExprToDecls(const Expr *E) {
   if (const auto *ME = dyn_cast<CXXDependentScopeMemberExpr>(E)) {
     return resolveMemberExpr(ME);
   }
@@ -236,7 +308,7 @@ HeuristicResolver::resolveExprToDecls(const Expr *E) const {
   return {};
 }
 
-const Type *HeuristicResolver::resolveExprToType(const Expr *E) const {
+const Type *HeuristicResolverImpl::resolveExprToType(const Expr *E) {
   std::vector<const NamedDecl *> Decls = resolveExprToDecls(E);
   if (!Decls.empty())
     return resolveDeclsToType(Decls, Ctx);
@@ -244,8 +316,8 @@ const Type *HeuristicResolver::resolveExprToType(const Expr *E) const {
   return E->getType().getTypePtr();
 }
 
-const Type *HeuristicResolver::resolveNestedNameSpecifierToType(
-    const NestedNameSpecifier *NNS) const {
+const Type *HeuristicResolverImpl::resolveNestedNameSpecifierToType(
+    const NestedNameSpecifier *NNS) {
   if (!NNS)
     return nullptr;
 
@@ -270,8 +342,6 @@ const Type *HeuristicResolver::resolveNestedNameSpecifierToType(
   return nullptr;
 }
 
-namespace {
-
 bool isOrdinaryMember(const NamedDecl *ND) {
   return ND->isInIdentifierNamespace(Decl::IDNS_Ordinary | Decl::IDNS_Tag |
                                      Decl::IDNS_Member);
@@ -287,11 +357,9 @@ bool findOrdinaryMember(const CXXRecordDecl *RD, CXXBasePath &Path,
   return false;
 }
 
-} // namespace
-
-bool HeuristicResolver::findOrdinaryMemberInDependentClasses(
+bool HeuristicResolverImpl::findOrdinaryMemberInDependentClasses(
     const CXXBaseSpecifier *Specifier, CXXBasePath &Path,
-    DeclarationName Name) const {
+    DeclarationName Name) {
   CXXRecordDecl *RD =
       resolveTypeToRecordDecl(Specifier->getType().getTypePtr());
   if (!RD)
@@ -299,9 +367,9 @@ bool HeuristicResolver::findOrdinaryMemberInDependentClasses(
   return findOrdinaryMember(RD, Path, Name);
 }
 
-std::vector<const NamedDecl *> HeuristicResolver::lookupDependentName(
+std::vector<const NamedDecl *> HeuristicResolverImpl::lookupDependentName(
     CXXRecordDecl *RD, DeclarationName Name,
-    llvm::function_ref<bool(const NamedDecl *ND)> Filter) const {
+    llvm::function_ref<bool(const NamedDecl *ND)> Filter) {
   std::vector<const NamedDecl *> Results;
 
   // Lookup in the class.
@@ -332,9 +400,9 @@ std::vector<const NamedDecl *> HeuristicResolver::lookupDependentName(
   return Results;
 }
 
-std::vector<const NamedDecl *> HeuristicResolver::resolveDependentMember(
+std::vector<const NamedDecl *> HeuristicResolverImpl::resolveDependentMember(
     const Type *T, DeclarationName Name,
-    llvm::function_ref<bool(const NamedDecl *ND)> Filter) const {
+    llvm::function_ref<bool(const NamedDecl *ND)> Filter) {
   if (!T)
     return {};
   if (auto *ET = T->getAs<EnumType>()) {
@@ -349,6 +417,44 @@ std::vector<const NamedDecl *> HeuristicResolver::resolveDependentMember(
   }
   return {};
 }
+} // namespace
+
+std::vector<const NamedDecl *> HeuristicResolver::resolveMemberExpr(
+    const CXXDependentScopeMemberExpr *ME) const {
+  return HeuristicResolverImpl(Ctx).resolveMemberExpr(ME);
+}
+std::vector<const NamedDecl *> HeuristicResolver::resolveDeclRefExpr(
+    const DependentScopeDeclRefExpr *RE) const {
+  return HeuristicResolverImpl(Ctx).resolveDeclRefExpr(RE);
+}
+std::vector<const NamedDecl *>
+HeuristicResolver::resolveTypeOfCallExpr(const CallExpr *CE) const {
+  return HeuristicResolverImpl(Ctx).resolveTypeOfCallExpr(CE);
+}
+std::vector<const NamedDecl *>
+HeuristicResolver::resolveCalleeOfCallExpr(const CallExpr *CE) const {
+  return HeuristicResolverImpl(Ctx).resolveCalleeOfCallExpr(CE);
+}
+std::vector<const NamedDecl *> HeuristicResolver::resolveUsingValueDecl(
+    const UnresolvedUsingValueDecl *UUVD) const {
+  return HeuristicResolverImpl(Ctx).resolveUsingValueDecl(UUVD);
+}
+std::vector<const NamedDecl *> HeuristicResolver::resolveDependentNameType(
+    const DependentNameType *DNT) const {
+  return HeuristicResolverImpl(Ctx).resolveDependentNameType(DNT);
+}
+std::vector<const NamedDecl *>
+HeuristicResolver::resolveTemplateSpecializationType(
+    const DependentTemplateSpecializationType *DTST) const {
+  return HeuristicResolverImpl(Ctx).resolveTemplateSpecializationType(DTST);
+}
+const Type *HeuristicResolver::resolveNestedNameSpecifierToType(
+    const NestedNameSpecifier *NNS) const {
+  return HeuristicResolverImpl(Ctx).resolveNestedNameSpecifierToType(NNS);
+}
+const Type *HeuristicResolver::getPointeeType(const Type *T) const {
+  return HeuristicResolverImpl(Ctx).getPointeeType(T);
+}
 
 } // namespace clangd
 } // namespace clang
diff --git a/clang-tools-extra/clangd/HeuristicResolver.h b/clang-tools-extra/clangd/HeuristicResolver.h
index dc04123d37593c..dcc063bbc4adc0 100644
--- a/clang-tools-extra/clangd/HeuristicResolver.h
+++ b/clang-tools-extra/clangd/HeuristicResolver.h
@@ -77,43 +77,6 @@ class HeuristicResolver {
 
 private:
   ASTContext &Ctx;
-
-  // Given a tag-decl type and a member name, heuristically resolve the
-  // name to one or more declarations.
-  // The current heuristic is simply to look up the name in the primary
-  // template. This is a heuristic because the template could potentially
-  // have specializations that declare different members.
-  // Multiple declarations could be returned if the name is overloaded
-  // (e.g. an overloaded method in the primary template).
-  // This heuristic will give the desired answer in many cases, e.g.
-  // for a call to vector<T>::size().
-  std::vector<const NamedDecl *> resolveDependentMember(
-      const Type *T, DeclarationName Name,
-      llvm::function_ref<bool(const NamedDecl *ND)> Filter) const;
-
-  // Try to heuristically resolve the type of a possibly-dependent expression
-  // `E`.
-  const Type *resolveExprToType(const Expr *E) const;
-  std::vector<const NamedDecl *> resolveExprToDecls(const Expr *E) const;
-
-  // Helper function for HeuristicResolver::resolveDependentMember()
-  // which takes a possibly-dependent type `T` and heuristically
-  // resolves it to a CXXRecordDecl in which we can try name lookup.
-  CXXRecordDecl *resolveTypeToRecordDecl(const Type *T) const;
-
-  // This is a reimplementation of CXXRecordDecl::lookupDependentName()
-  // so that the implementation can call into other HeuristicResolver helpers.
-  // FIXME: Once HeuristicResolver is upstreamed to the clang libraries
-  // (https://github.com/clangd/clangd/discussions/1662),
-  // CXXRecordDecl::lookupDepenedentName() can be removed, and its call sites
-  // can be modified to benefit from the more comprehensive heuristics offered
-  // by HeuristicResolver instead.
-  std::vector<const NamedDecl *> lookupDependentName(
-      CXXRecordDecl *RD, DeclarationName Name,
-      llvm::function_ref<bool(const NamedDecl *ND)> Filter) const;
-  bool findOrdinaryMemberInDependentClasses(const CXXBaseSpecifier *Specifier,
-                                            CXXBasePath &Path,
-                                            DeclarationName Name) const;
 };
 
 } // namespace clangd
diff --git a/clang-tools-extra/clangd/unittests/FindTargetTests.cpp b/clang-tools-extra/clangd/unittests/FindTargetTests.cpp
index 29cff68cf03b2e..0af6036734ba53 100644
--- a/clang-tools-extra/clangd/unittests/FindTargetTests.cpp
+++ b/clang-tools-extra/clangd/unittests/FindTargetTests.cpp
@@ -1009,6 +1009,33 @@ TEST_F(TargetDeclTest, DependentTypes) {
       )cpp";
   EXPECT_DECLS("DependentTemplateSpecializationTypeLoc",
                "template <typename> struct B");
+
+  // Dependent name with recursive definition. We don't expect a
+  // result, but we shouldn't get into a stack overflow either.
+  Code = R"cpp(
+        template <int N>
+        struct waldo {
+          typedef typename waldo<N - 1>::type::[[next]] type;
+        };
+  )cpp";
+  EXPECT_DECLS("DependentNameTypeLoc");
+
+  // Similar to above but using mutually recursive templates.
+  Code = R"cpp(
+        template <int N>
+        struct odd;
+
+        template <int N>
+        struct even {
+          using type = typename odd<N - 1>::type::next;
+        };
+
+        template <int N>
+        struct odd {
+          using type = typename even<N - 1>::type::[[next]];
+        };
+  )cpp";
+  EXPECT_DECLS("DependentNameTypeLoc");
 }
 
 TEST_F(TargetDeclTest, TypedefCascade) {
diff --git a/libcxx/test/tools/clang_tidy_checks/CMakeLists.txt b/libcxx/test/tools/clang_tidy_checks/CMakeLists.txt
index 978e7095216522..a52140e2b9938a 100644
--- a/libcxx/test/tools/clang_tidy_checks/CMakeLists.txt
+++ b/libcxx/test/tools/clang_tidy_checks/CMakeLists.txt
@@ -5,7 +5,7 @@
 set(LLVM_DIR_SAVE ${LLVM_DIR})
 set(Clang_DIR_SAVE ${Clang_DIR})
 
-find_package(Clang 18)
+find_package(Clang 18.1)
 if (NOT Clang_FOUND)
   find_package(Clang 17)
 endif()
diff --git a/lld/ELF/Arch/LoongArch.cpp b/lld/ELF/Arch/LoongArch.cpp
index 8a6f6db68f2909..464f5dfb320ccc 100644
--- a/lld/ELF/Arch/LoongArch.cpp
+++ b/lld/ELF/Arch/LoongArch.cpp
@@ -159,8 +159,9 @@ static bool isJirl(uint32_t insn) {
 static void handleUleb128(uint8_t *loc, uint64_t val) {
   const uint32_t maxcount = 1 + 64 / 7;
   uint32_t count;
-  uint64_t orig = decodeULEB128(loc, &count);
-  if (count > maxcount)
+  const char *error = nullptr;
+  uint64_t orig = decodeULEB128(loc, &count, nullptr, &error);
+  if (count > maxcount || (count == maxcount && error))
     errorOrWarn(getErrorLocation(loc) + "extra space for uleb128");
   uint64_t mask = count < maxcount ? (1ULL << 7 * count) - 1 : -1ULL;
   encodeULEB128((orig + val) & mask, loc, count);
diff --git a/lld/test/COFF/def-export-cpp.s b/lld/test/COFF/def-export-cpp.s
index e00b35b1c5b39b..370b8ddba4104b 100644
--- a/lld/test/COFF/def-export-cpp.s
+++ b/lld/test/COFF/def-export-cpp.s
@@ -10,6 +10,7 @@
 
 # IMPLIB: File: foo.dll
 # IMPLIB: Name type: undecorate
+# IMPLIB-NEXT: Export name: GetPathOnDisk
 # IMPLIB-NEXT: Symbol: __imp_?GetPathOnDisk@@YA_NPEA_W@Z
 # IMPLIB-NEXT: Symbol: ?GetPathOnDisk@@YA_NPEA_W@Z
 
diff --git a/lld/test/COFF/def-export-stdcall.s b/lld/test/COFF/def-export-stdcall.s
index f015e205c74a33..7e4e04c77cbe7a 100644
--- a/lld/test/COFF/def-export-stdcall.s
+++ b/lld/test/COFF/def-export-stdcall.s
@@ -6,15 +6,19 @@
 # RUN: llvm-readobj --coff-exports %t.dll | FileCheck -check-prefix UNDECORATED-EXPORTS %s
 
 # UNDECORATED-IMPLIB: Name type: noprefix
+# UNDECORATED-IMPLIB-NEXT: Export name: _underscored
 # UNDECORATED-IMPLIB-NEXT: __imp___underscored
 # UNDECORATED-IMPLIB-NEXT: __underscored
 # UNDECORATED-IMPLIB: Name type: undecorate
+# UNDECORATED-IMPLIB-NEXT: Export name: fastcall
 # UNDECORATED-IMPLIB-NEXT: __imp_@fastcall@8
 # UNDECORATED-IMPLIB-NEXT: fastcall@8
 # UNDECORATED-IMPLIB: Name type: undecorate
+# UNDECORATED-IMPLIB-NEXT: Export name: stdcall
 # UNDECORATED-IMPLIB-NEXT: __imp__stdcall@8
 # UNDECORATED-IMPLIB-NEXT: _stdcall@8
 # UNDECORATED-IMPLIB: Name type: undecorate
+# UNDECORATED-IMPLIB-NEXT: Export name: vectorcall
 # UNDECORATED-IMPLIB-NEXT: __imp_vectorcall@@8
 # UNDECORATED-IMPLIB-NEXT: vectorcall@@8
 
@@ -30,12 +34,15 @@
 # RUN: llvm-readobj --coff-exports %t.dll | FileCheck -check-prefix DECORATED-EXPORTS %s
 
 # DECORATED-IMPLIB: Name type: name
+# DECORATED-IMPLIB-NEXT: Export name: @fastcall@8
 # DECORATED-IMPLIB-NEXT: __imp_@fastcall@8
 # DECORATED-IMPLIB-NEXT: @fastcall@8
 # DECORATED-IMPLIB: Name type: name
+# DECORATED-IMPLIB-NEXT: Export name: _stdcall@8
 # DECORATED-IMPLIB-NEXT: __imp__stdcall@8
 # DECORATED-IMPLIB-NEXT: _stdcall@8
 # DECORATED-IMPLIB: Name type: name
+# DECORATED-IMPLIB-NEXT: Export name: vectorcall@@8
 # DECORATED-IMPLIB-NEXT: __imp_vectorcall@@8
 # DECORATED-IMPLIB-NEXT: vectorcall@@8
 
@@ -51,14 +58,17 @@
 # RUN: llvm-readobj --coff-exports %t.dll | FileCheck -check-prefix DECORATED-MINGW-EXPORTS %s
 
 # DECORATED-MINGW-IMPLIB: Name type: name
+# DECORATED-MINGW-IMPLIB-NEXT: Export name: @fastcall@8
 # DECORATED-MINGW-IMPLIB-NEXT: __imp_@fastcall@8
 # DECORATED-MINGW-IMPLIB-NEXT: fastcall@8
 # DECORATED-MINGW-IMPLIB: Name type: noprefix
+# DECORATED-MINGW-IMPLIB-NEXT: Export name: stdcall@8
 # DECORATED-MINGW-IMPLIB-NEXT: __imp__stdcall@8
 # DECORATED-MINGW-IMPLIB-NEXT: _stdcall@8
 # GNU tools don't support vectorcall, but this test is just to track that
 # lld's behaviour remains consistent over time.
 # DECORATED-MINGW-IMPLIB: Name type: name
+# DECORATED-MINGW-IMPLIB-NEXT: Export name: vectorcall@@8
 # DECORATED-MINGW-IMPLIB-NEXT: __imp_vectorcall@@8
 # DECORATED-MINGW-IMPLIB-NEXT: vectorcall@@8
 
@@ -75,14 +85,17 @@
 # RUN: llvm-readobj --coff-exports %t.dll | FileCheck -check-prefix MINGW-KILL-AT-EXPORTS %s
 
 # MINGW-KILL-AT-IMPLIB: Name type: noprefix
+# MINGW-KILL-AT-IMPLIB: Export name: fastcall
 # MINGW-KILL-AT-IMPLIB: __imp__fastcall
 # MINGW-KILL-AT-IMPLIB-NEXT: _fastcall
 # MINGW-KILL-AT-IMPLIB: Name type: noprefix
+# MINGW-KILL-AT-IMPLIB-NEXT: Export name: stdcall
 # MINGW-KILL-AT-IMPLIB-NEXT: __imp__stdcall
 # MINGW-KILL-AT-IMPLIB-NEXT: _stdcall
 # GNU tools don't support vectorcall, but this test is just to track that
 # lld's behaviour remains consistent over time.
 # MINGW-KILL-AT-IMPLIB: Name type: noprefix
+# MINGW-KILL-AT-IMPLIB-NEXT: Export name: vectorcall
 # MINGW-KILL-AT-IMPLIB-NEXT: __imp__vectorcall
 # MINGW-KILL-AT-IMPLIB-NEXT: _vectorcall
 
diff --git a/lld/test/COFF/dllexport.s b/lld/test/COFF/dllexport.s
index a238b70ce1b4f6..b04ebc3a33c3e2 100644
--- a/lld/test/COFF/dllexport.s
+++ b/lld/test/COFF/dllexport.s
@@ -6,15 +6,19 @@
 # RUN: llvm-readobj --coff-exports %t.dll | FileCheck -check-prefix DECORATED-EXPORTS %s
 
 # DECORATED-IMPLIB: Name type: name
+# DECORATED-IMPLIB-NEXT: Export name: @fastcall@8
 # DECORATED-IMPLIB-NEXT: __imp_@fastcall@8
 # DECORATED-IMPLIB-NEXT: @fastcall@8
 # DECORATED-IMPLIB: Name type: name
+# DECORATED-IMPLIB-NEXT: Export name: _stdcall@8
 # DECORATED-IMPLIB-NEXT: __imp__stdcall@8
 # DECORATED-IMPLIB-NEXT: _stdcall@8
 # DECORATED-IMPLIB: Name type: noprefix
+# DECORATED-IMPLIB-NEXT: Export name: _underscored
 # DECORATED-IMPLIB-NEXT: __imp___underscored
 # DECORATED-IMPLIB-NEXT: __underscored
 # DECORATED-IMPLIB: Name type: name
+# DECORATED-IMPLIB-NEXT: Export name: vectorcall@@8
 # DECORATED-IMPLIB-NEXT: __imp_vectorcall@@8
 # DECORATED-IMPLIB-NEXT: vectorcall@@8
 
diff --git a/lld/test/ELF/loongarch-reloc-leb128.s b/lld/test/ELF/loongarch-reloc-leb128.s
index 9e6f221e62b639..2dd327d1564ebd 100644
--- a/lld/test/ELF/loongarch-reloc-leb128.s
+++ b/lld/test/ELF/loongarch-reloc-leb128.s
@@ -99,4 +99,4 @@ w2:
 .reloc ., R_LARCH_ADD_ULEB128, w2
 .reloc ., R_LARCH_SUB_ULEB128, w1
 .fill 10, 1, 0x80
-.byte 0
+.byte 1
diff --git a/llvm/include/llvm/BinaryFormat/COFF.h b/llvm/include/llvm/BinaryFormat/COFF.h
index 522ee37da6e830..72461d0d9c316a 100644
--- a/llvm/include/llvm/BinaryFormat/COFF.h
+++ b/llvm/include/llvm/BinaryFormat/COFF.h
@@ -716,7 +716,10 @@ enum ImportNameType : unsigned {
   IMPORT_NAME_NOPREFIX = 2,
   /// The import name is the public symbol name, but skipping the leading ?,
   /// @, or optionally _, and truncating at the first @.
-  IMPORT_NAME_UNDECORATE = 3
+  IMPORT_NAME_UNDECORATE = 3,
+  /// The import name is specified as a separate string in the import library
+  /// object file.
+  IMPORT_NAME_EXPORTAS = 4
 };
 
 enum class GuardFlags : uint32_t {
diff --git a/llvm/include/llvm/Object/COFF.h b/llvm/include/llvm/Object/COFF.h
index a548b2c15c5fdc..2a5c3d8913b15c 100644
--- a/llvm/include/llvm/Object/COFF.h
+++ b/llvm/include/llvm/Object/COFF.h
@@ -1362,6 +1362,47 @@ class SectionStrippedError
   SectionStrippedError() { setErrorCode(object_error::section_stripped); }
 };
 
+inline std::optional<std::string>
+getArm64ECMangledFunctionName(StringRef Name) {
+  bool IsCppFn = Name[0] == '?';
+  if (IsCppFn && Name.find("$$h") != std::string::npos)
+    return std::nullopt;
+  if (!IsCppFn && Name[0] == '#')
+    return std::nullopt;
+
+  StringRef Prefix = "$$h";
+  size_t InsertIdx = 0;
+  if (IsCppFn) {
+    InsertIdx = Name.find("@@");
+    size_t ThreeAtSignsIdx = Name.find("@@@");
+    if (InsertIdx != std::string::npos && InsertIdx != ThreeAtSignsIdx) {
+      InsertIdx += 2;
+    } else {
+      InsertIdx = Name.find("@");
+      if (InsertIdx != std::string::npos)
+        InsertIdx++;
+    }
+  } else {
+    Prefix = "#";
+  }
+
+  return std::optional<std::string>(
+      (Name.substr(0, InsertIdx) + Prefix + Name.substr(InsertIdx)).str());
+}
+
+inline std::optional<std::string>
+getArm64ECDemangledFunctionName(StringRef Name) {
+  if (Name[0] == '#')
+    return std::string(Name.substr(1));
+  if (Name[0] != '?')
+    return std::nullopt;
+
+  std::pair<StringRef, StringRef> Pair = Name.split("$$h");
+  if (Pair.second.empty())
+    return std::nullopt;
+  return (Pair.first + Pair.second).str();
+}
+
 } // end namespace object
 
 } // end namespace llvm
diff --git a/llvm/include/llvm/Object/COFFImportFile.h b/llvm/include/llvm/Object/COFFImportFile.h
index edc836ff0348cb..8358197309f000 100644
--- a/llvm/include/llvm/Object/COFFImportFile.h
+++ b/llvm/include/llvm/Object/COFFImportFile.h
@@ -26,7 +26,16 @@
 namespace llvm {
 namespace object {
 
+constexpr std::string_view ImportDescriptorPrefix = "__IMPORT_DESCRIPTOR_";
+constexpr std::string_view NullImportDescriptorSymbolName =
+    "__NULL_IMPORT_DESCRIPTOR";
+constexpr std::string_view NullThunkDataPrefix = "\x7f";
+constexpr std::string_view NullThunkDataSuffix = "_NULL_THUNK_DATA";
+
 class COFFImportFile : public SymbolicFile {
+private:
+  enum SymbolIndex { ImpSymbol, ThunkSymbol, ECAuxSymbol, ECThunkSymbol };
+
 public:
   COFFImportFile(MemoryBufferRef Source)
       : SymbolicFile(ID_COFFImportFile, Source) {}
@@ -36,9 +45,23 @@ class COFFImportFile : public SymbolicFile {
   void moveSymbolNext(DataRefImpl &Symb) const override { ++Symb.p; }
 
   Error printSymbolName(raw_ostream &OS, DataRefImpl Symb) const override {
-    if (Symb.p == 0)
+    switch (Symb.p) {
+    case ImpSymbol:
       OS << "__imp_";
-    OS << StringRef(Data.getBufferStart() + sizeof(coff_import_header));
+      break;
+    case ECAuxSymbol:
+      OS << "__imp_aux_";
+      break;
+    }
+    const char *Name = Data.getBufferStart() + sizeof(coff_import_header);
+    if (Symb.p != ECThunkSymbol && COFF::isArm64EC(getMachine())) {
+      if (std::optional<std::string> DemangledName =
+              getArm64ECDemangledFunctionName(Name)) {
+        OS << StringRef(*DemangledName);
+        return Error::success();
+      }
+    }
+    OS << StringRef(Name);
     return Error::success();
   }
 
@@ -52,7 +75,12 @@ class COFFImportFile : public SymbolicFile {
 
   basic_symbol_iterator symbol_end() const override {
     DataRefImpl Symb;
-    Symb.p = isData() ? 1 : 2;
+    if (isData())
+      Symb.p = ImpSymbol + 1;
+    else if (COFF::isArm64EC(getMachine()))
+      Symb.p = ECThunkSymbol + 1;
+    else
+      Symb.p = ThunkSymbol + 1;
     return BasicSymbolRef(Symb, this);
   }
 
@@ -66,6 +94,7 @@ class COFFImportFile : public SymbolicFile {
   uint16_t getMachine() const { return getCOFFImportHeader()->Machine; }
 
   StringRef getFileFormatName() const;
+  StringRef getExportName() const;
 
 private:
   bool isData() const {
diff --git a/llvm/lib/Object/ArchiveWriter.cpp b/llvm/lib/Object/ArchiveWriter.cpp
index 155926a8c5949d..1a7ed2db543964 100644
--- a/llvm/lib/Object/ArchiveWriter.cpp
+++ b/llvm/lib/Object/ArchiveWriter.cpp
@@ -677,6 +677,13 @@ static bool isECObject(object::SymbolicFile &Obj) {
   return false;
 }
 
+bool isImportDescriptor(StringRef Name) {
+  return Name.starts_with(ImportDescriptorPrefix) ||
+         Name == StringRef{NullImportDescriptorSymbolName} ||
+         (Name.starts_with(NullThunkDataPrefix) &&
+          Name.ends_with(NullThunkDataSuffix));
+}
+
 static Expected<std::vector<unsigned>> getSymbols(SymbolicFile *Obj,
                                                   uint16_t Index,
                                                   raw_ostream &SymNames,
@@ -704,6 +711,10 @@ static Expected<std::vector<unsigned>> getSymbols(SymbolicFile *Obj,
       if (Map == &SymMap->Map) {
         Ret.push_back(SymNames.tell());
         SymNames << Name << '\0';
+        // If EC is enabled, then the import descriptors are NOT put into EC
+        // objects so we need to copy them to the EC map manually.
+        if (SymMap->UseECMap && isImportDescriptor(Name))
+          SymMap->ECMap[Name] = Index;
       }
     } else {
       Ret.push_back(SymNames.tell());
diff --git a/llvm/lib/Object/COFFImportFile.cpp b/llvm/lib/Object/COFFImportFile.cpp
index 60556c149bf735..d3b5cf2d9f7b52 100644
--- a/llvm/lib/Object/COFFImportFile.cpp
+++ b/llvm/lib/Object/COFFImportFile.cpp
@@ -52,6 +52,38 @@ StringRef COFFImportFile::getFileFormatName() const {
   }
 }
 
+StringRef COFFImportFile::getExportName() const {
+  const coff_import_header *hdr = getCOFFImportHeader();
+  StringRef name = Data.getBuffer().substr(sizeof(*hdr)).split('\0').first;
+
+  auto ltrim1 = [](StringRef s, StringRef chars) {
+    return !s.empty() && chars.contains(s[0]) ? s.substr(1) : s;
+  };
+
+  switch (hdr->getNameType()) {
+  case IMPORT_ORDINAL:
+    name = "";
+    break;
+  case IMPORT_NAME_NOPREFIX:
+    name = ltrim1(name, "?@_");
+    break;
+  case IMPORT_NAME_UNDECORATE:
+    name = ltrim1(name, "?@_");
+    name = name.substr(0, name.find('@'));
+    break;
+  case IMPORT_NAME_EXPORTAS: {
+    // Skip DLL name
+    name = Data.getBuffer().substr(sizeof(*hdr) + name.size() + 1);
+    name = name.split('\0').second.split('\0').first;
+    break;
+  }
+  default:
+    break;
+  }
+
+  return name;
+}
+
 static uint16_t getImgRelRelocation(MachineTypes Machine) {
   switch (Machine) {
   default:
@@ -76,7 +108,7 @@ template <class T> static void append(std::vector<uint8_t> &B, const T &Data) {
 }
 
 static void writeStringTable(std::vector<uint8_t> &B,
-                             ArrayRef<const std::string> Strings) {
+                             ArrayRef<const std::string_view> Strings) {
   // The COFF string table consists of a 4-byte value which is the size of the
   // table, including the length field itself.  This value is followed by the
   // string content itself, which is an array of null-terminated C-style
@@ -139,9 +171,6 @@ static Expected<std::string> replace(StringRef S, StringRef From,
   return (Twine(S.substr(0, Pos)) + To + S.substr(Pos + From.size())).str();
 }
 
-static const std::string NullImportDescriptorSymbolName =
-    "__NULL_IMPORT_DESCRIPTOR";
-
 namespace {
 // This class constructs various small object files necessary to support linking
 // symbols imported from a DLL.  The contents are pretty strictly defined and
@@ -160,8 +189,9 @@ class ObjectFactory {
 public:
   ObjectFactory(StringRef S, MachineTypes M)
       : NativeMachine(M), ImportName(S), Library(llvm::sys::path::stem(S)),
-        ImportDescriptorSymbolName(("__IMPORT_DESCRIPTOR_" + Library).str()),
-        NullThunkSymbolName(("\x7f" + Library + "_NULL_THUNK_DATA").str()) {}
+        ImportDescriptorSymbolName((ImportDescriptorPrefix + Library).str()),
+        NullThunkSymbolName(
+            (NullThunkDataPrefix + Library + NullThunkDataSuffix).str()) {}
 
   // Creates an Import Descriptor.  This is a small object file which contains a
   // reference to the terminators and contains the library name (entry) for the
@@ -183,6 +213,7 @@ class ObjectFactory {
   // Library Format.
   NewArchiveMember createShortImport(StringRef Sym, uint16_t Ordinal,
                                      ImportType Type, ImportNameType NameType,
+                                     StringRef ExportName,
                                      MachineTypes Machine);
 
   // Create a weak external file which is described in PE/COFF Aux Format 3.
@@ -474,12 +505,13 @@ NewArchiveMember ObjectFactory::createNullThunk(std::vector<uint8_t> &Buffer) {
   return {MemoryBufferRef{F, ImportName}};
 }
 
-NewArchiveMember ObjectFactory::createShortImport(StringRef Sym,
-                                                  uint16_t Ordinal,
-                                                  ImportType ImportType,
-                                                  ImportNameType NameType,
-                                                  MachineTypes Machine) {
+NewArchiveMember
+ObjectFactory::createShortImport(StringRef Sym, uint16_t Ordinal,
+                                 ImportType ImportType, ImportNameType NameType,
+                                 StringRef ExportName, MachineTypes Machine) {
   size_t ImpSize = ImportName.size() + Sym.size() + 2; // +2 for NULs
+  if (!ExportName.empty())
+    ImpSize += ExportName.size() + 1;
   size_t Size = sizeof(coff_import_header) + ImpSize;
   char *Buf = Alloc.Allocate<char>(Size);
   memset(Buf, 0, Size);
@@ -499,6 +531,10 @@ NewArchiveMember ObjectFactory::createShortImport(StringRef Sym,
   memcpy(P, Sym.data(), Sym.size());
   P += Sym.size() + 1;
   memcpy(P, ImportName.data(), ImportName.size());
+  if (!ExportName.empty()) {
+    P += ImportName.size() + 1;
+    memcpy(P, ExportName.data(), ExportName.size());
+  }
 
   return {MemoryBufferRef(StringRef(Buf, Size), ImportName)};
 }
@@ -615,27 +651,51 @@ Error writeImportLibrary(StringRef ImportName, StringRef Path,
       ImportType = IMPORT_CONST;
 
     StringRef SymbolName = E.SymbolName.empty() ? E.Name : E.SymbolName;
-    ImportNameType NameType = E.Noname
-                                  ? IMPORT_ORDINAL
-                                  : getNameType(SymbolName, E.Name,
-                                                Machine, MinGW);
-    Expected<std::string> Name = E.ExtName.empty()
-                                     ? std::string(SymbolName)
-                                     : replace(SymbolName, E.Name, E.ExtName);
-
-    if (!Name)
-      return Name.takeError();
-
-    if (!E.AliasTarget.empty() && *Name != E.AliasTarget) {
+    std::string Name;
+
+    if (E.ExtName.empty()) {
+      Name = std::string(SymbolName);
+    } else {
+      Expected<std::string> ReplacedName =
+          replace(SymbolName, E.Name, E.ExtName);
+      if (!ReplacedName)
+        return ReplacedName.takeError();
+      Name.swap(*ReplacedName);
+    }
+
+    if (!E.AliasTarget.empty() && Name != E.AliasTarget) {
       Members.push_back(
-          OF.createWeakExternal(E.AliasTarget, *Name, false, Machine));
+          OF.createWeakExternal(E.AliasTarget, Name, false, Machine));
       Members.push_back(
-          OF.createWeakExternal(E.AliasTarget, *Name, true, Machine));
+          OF.createWeakExternal(E.AliasTarget, Name, true, Machine));
       continue;
     }
 
-    Members.push_back(
-        OF.createShortImport(*Name, E.Ordinal, ImportType, NameType, Machine));
+    ImportNameType NameType;
+    std::string ExportName;
+    if (E.Noname) {
+      NameType = IMPORT_ORDINAL;
+    } else {
+      NameType = getNameType(SymbolName, E.Name, Machine, MinGW);
+    }
+
+    // On ARM64EC, use EXPORTAS to import demangled name for mangled symbols.
+    if (ImportType == IMPORT_CODE && isArm64EC(Machine)) {
+      if (std::optional<std::string> MangledName =
+              getArm64ECMangledFunctionName(Name)) {
+        if (ExportName.empty()) {
+          NameType = IMPORT_NAME_EXPORTAS;
+          ExportName.swap(Name);
+        }
+        Name = std::move(*MangledName);
+      } else if (ExportName.empty()) {
+        NameType = IMPORT_NAME_EXPORTAS;
+        ExportName = std::move(*getArm64ECDemangledFunctionName(Name));
+      }
+    }
+
+    Members.push_back(OF.createShortImport(Name, E.Ordinal, ImportType,
+                                           NameType, ExportName, Machine));
   }
 
   return writeArchive(Path, Members, SymtabWritingMode::NormalSymtab,
diff --git a/llvm/lib/Target/AArch64/AArch64Arm64ECCallLowering.cpp b/llvm/lib/Target/AArch64/AArch64Arm64ECCallLowering.cpp
index 03d641d04413ef..55c5bbc66a3f4f 100644
--- a/llvm/lib/Target/AArch64/AArch64Arm64ECCallLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64Arm64ECCallLowering.cpp
@@ -24,11 +24,13 @@
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/Instruction.h"
 #include "llvm/InitializePasses.h"
+#include "llvm/Object/COFF.h"
 #include "llvm/Pass.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/TargetParser/Triple.h"
 
 using namespace llvm;
+using namespace llvm::object;
 
 using OperandBundleDef = OperandBundleDefT<Value *>;
 
diff --git a/llvm/lib/Target/AArch64/AArch64MCInstLower.cpp b/llvm/lib/Target/AArch64/AArch64MCInstLower.cpp
index 1e12cf545fa777..37d621cd2f6580 100644
--- a/llvm/lib/Target/AArch64/AArch64MCInstLower.cpp
+++ b/llvm/lib/Target/AArch64/AArch64MCInstLower.cpp
@@ -23,11 +23,13 @@
 #include "llvm/MC/MCExpr.h"
 #include "llvm/MC/MCInst.h"
 #include "llvm/MC/MCStreamer.h"
+#include "llvm/Object/COFF.h"
 #include "llvm/Support/CodeGen.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Target/TargetLoweringObjectFile.h"
 #include "llvm/Target/TargetMachine.h"
 using namespace llvm;
+using namespace llvm::object;
 
 extern cl::opt<bool> EnableAArch64ELFLocalDynamicTLSGeneration;
 
diff --git a/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.h b/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.h
index 10e69655f77e10..8b32d593d2a812 100644
--- a/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.h
+++ b/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.h
@@ -248,34 +248,6 @@ static inline bool atomicBarrierDroppedOnZero(unsigned Opcode) {
   return false;
 }
 
-static inline std::optional<std::string>
-getArm64ECMangledFunctionName(std::string Name) {
-  bool IsCppFn = Name[0] == '?';
-  if (IsCppFn && Name.find("$$h") != std::string::npos)
-    return std::nullopt;
-  if (!IsCppFn && Name[0] == '#')
-    return std::nullopt;
-
-  StringRef Prefix = "$$h";
-  size_t InsertIdx = 0;
-  if (IsCppFn) {
-    InsertIdx = Name.find("@@");
-    size_t ThreeAtSignsIdx = Name.find("@@@");
-    if (InsertIdx != std::string::npos && InsertIdx != ThreeAtSignsIdx) {
-      InsertIdx += 2;
-    } else {
-      InsertIdx = Name.find("@");
-      if (InsertIdx != std::string::npos)
-        InsertIdx++;
-    }
-  } else {
-    Prefix = "#";
-  }
-
-  Name.insert(Name.begin() + InsertIdx, Prefix.begin(), Prefix.end());
-  return std::optional<std::string>(Name);
-}
-
 namespace AArch64CC {
 
 // The CondCodes constants map directly to the 4-bit encoding of the condition
diff --git a/llvm/test/tools/llvm-dlltool/coff-decorated.def b/llvm/test/tools/llvm-dlltool/coff-decorated.def
index 856804686168b1..fc81f23d09d6c4 100644
--- a/llvm/test/tools/llvm-dlltool/coff-decorated.def
+++ b/llvm/test/tools/llvm-dlltool/coff-decorated.def
@@ -14,25 +14,32 @@ OtherStdcallExportName@4=CdeclInternalFunction
 CdeclExportName=StdcallInternalFunction@4
 
 ; CHECK:      Name type: noprefix
+; CHECK-NEXT: Export name: CdeclFunction
 ; CHECK-NEXT: Symbol: __imp__CdeclFunction
 ; CHECK-NEXT: Symbol: _CdeclFunction
 ; CHECK:      Name type: undecorate
+; CHECK-NEXT: Export name: StdcallFunction
 ; CHECK-NEXT: Symbol: __imp__StdcallFunction@4
 ; CHECK-NEXT: Symbol: _StdcallFunction@4
 ; CHECK:      Name type: undecorate
+; CHECK-NEXT: Export name: FastcallFunction
 ; CHECK-NEXT: Symbol: __imp_@FastcallFunction@4
 ; CHECK-NEXT: Symbol: @FastcallFunction@4
 ; CHECK:      Name type: name
+; CHECK-NEXT: Export name: ??_7exception@@6B@
 ; CHECK-NEXT: Symbol: __imp_??_7exception@@6B@
 ; CHECK-NEXT: Symbol: ??_7exception@@6B@
 ; CHECK-NM: W _StdcallAlias@4
 ; CHECK-NM: U _StdcallFunction@4
 ; CHECK:      Name type: undecorate
+; CHECK-NEXT: Export name: StdcallExportName
 ; CHECK-NEXT: Symbol: __imp__StdcallExportName@4{{$}}
 ; CHECK-NEXT: Symbol: _StdcallExportName@4{{$}}
 ; CHECK:      Name type: undecorate
+; CHECK-NEXT: Export name: OtherStdcallExportName
 ; CHECK-NEXT: Symbol: __imp__OtherStdcallExportName@4{{$}}
 ; CHECK-NEXT: Symbol: _OtherStdcallExportName@4{{$}}
 ; CHECK:      Name type: noprefix
+; CHECK-NEXT: Export name: CdeclExportName
 ; CHECK-NEXT: Symbol: __imp__CdeclExportName
 ; CHECK-NEXT: Symbol: _CdeclExportName
diff --git a/llvm/test/tools/llvm-dlltool/coff-exports.def b/llvm/test/tools/llvm-dlltool/coff-exports.def
index 57c55744602156..267424db1b8c1d 100644
--- a/llvm/test/tools/llvm-dlltool/coff-exports.def
+++ b/llvm/test/tools/llvm-dlltool/coff-exports.def
@@ -17,12 +17,15 @@ AnotherFunction
 ; CHECK-ARM64: Format: COFF-import-file-ARM64
 ; CHECK: Type: code
 ; CHECK:      Name type: name
+; CHECK-NEXT: Export name: TestFunction1
 ; CHECK-NEXT: Symbol: __imp_TestFunction1
 ; CHECK-NEXT: Symbol: TestFunction1
 ; CHECK:      Name type: name
+; CHECK-NEXT: Export name: TestFunction2
 ; CHECK-NEXT: Symbol: __imp_TestFunction2{{$}}
 ; CHECK-NEXT: Symbol: TestFunction2{{$}}
 ; CHECK:      Name type: name
+; CHECK-NEXT: Export name: TestFunction3
 ; CHECK-NEXT: Symbol: __imp_TestFunction3{{$}}
 ; CHECK-NEXT: Symbol: TestFunction3{{$}}
 
diff --git a/llvm/test/tools/llvm-dlltool/coff-noname.def b/llvm/test/tools/llvm-dlltool/coff-noname.def
index 27e60efbd2d802..7cb05846ce28a2 100644
--- a/llvm/test/tools/llvm-dlltool/coff-noname.def
+++ b/llvm/test/tools/llvm-dlltool/coff-noname.def
@@ -12,5 +12,6 @@ ByNameFunction
 ; CHECK-NEXT: Symbol: __imp__ByOrdinalFunction
 ; CHECK-NEXT: Symbol: _ByOrdinalFunction
 ; CHECK:      Name type: noprefix
+; CHECK-NEXT: Export name: ByNameFunction
 ; CHECK-NEXT: Symbol: __imp__ByNameFunction
 ; CHECK-NEXT: Symbol: _ByNameFunction
diff --git a/llvm/test/tools/llvm-dlltool/no-leading-underscore.def b/llvm/test/tools/llvm-dlltool/no-leading-underscore.def
index 6b78e15d2b5f69..9c5e77ca29a821 100644
--- a/llvm/test/tools/llvm-dlltool/no-leading-underscore.def
+++ b/llvm/test/tools/llvm-dlltool/no-leading-underscore.def
@@ -9,9 +9,11 @@ alias == func
 DecoratedFunction@4
 
 ; CHECK:      Name type: name
+; CHECK-NEXT: Export name: func
 ; CHECK-NEXT: Symbol: __imp_func
 ; CHECK-NEXT: Symbol: func
 ; CHECK:      Name type: undecorate
+; CHECK-NEXT: Export name: DecoratedFunction
 ; CHECK-NEXT: Symbol: __imp_DecoratedFunction@4
 ; CHECK-NEXT: Symbol: DecoratedFunction@4
 
diff --git a/llvm/test/tools/llvm-lib/arm64ec-implib.test b/llvm/test/tools/llvm-lib/arm64ec-implib.test
index 2672f8d38b7f70..ebc1b166ee4ea6 100644
--- a/llvm/test/tools/llvm-lib/arm64ec-implib.test
+++ b/llvm/test/tools/llvm-lib/arm64ec-implib.test
@@ -11,9 +11,26 @@ ARMAP-NEXT: __NULL_IMPORT_DESCRIPTOR in test.dll
 ARMAP-NEXT: test_NULL_THUNK_DATA in test.dll
 ARMAP-EMPTY:
 ARMAP-NEXT: Archive EC map
+ARMAP-NEXT: #expname in test.dll
+ARMAP-NEXT: #funcexp in test.dll
+ARMAP-NEXT: #mangledfunc in test.dll
+ARMAP-NEXT: ?test_cpp_func@@$$hYAHPEAX@Z in test.dll
+ARMAP-NEXT: ?test_cpp_func@@YAHPEAX@Z in test.dll
+ARMAP-NEXT: __IMPORT_DESCRIPTOR_test in test.dll
+ARMAP-NEXT: __NULL_IMPORT_DESCRIPTOR in test.dll
+ARMAP-NEXT: __imp_?test_cpp_func@@YAHPEAX@Z in test.dll
+ARMAP-NEXT: __imp_aux_?test_cpp_func@@YAHPEAX@Z in test.dll
+ARMAP-NEXT: __imp_aux_expname in test.dll
+ARMAP-NEXT: __imp_aux_funcexp in test.dll
+ARMAP-NEXT: __imp_aux_mangledfunc in test.dll
 ARMAP-NEXT: __imp_dataexp in test.dll
+ARMAP-NEXT: __imp_expname in test.dll
 ARMAP-NEXT: __imp_funcexp in test.dll
+ARMAP-NEXT: __imp_mangledfunc in test.dll
+ARMAP-NEXT: expname in test.dll
 ARMAP-NEXT: funcexp in test.dll
+ARMAP-NEXT: mangledfunc in test.dll
+ARMAP-NEXT: test_NULL_THUNK_DATA in test.dll
 
 RUN: llvm-readobj test.lib | FileCheck -check-prefix=READOBJ %s
 
@@ -35,14 +52,48 @@ READOBJ-EMPTY:
 READOBJ-NEXT: File: test.dll
 READOBJ-NEXT: Format: COFF-import-file-ARM64EC
 READOBJ-NEXT: Type: code
-READOBJ-NEXT: Name type: name
+READOBJ-NEXT: Name type: export as
+READOBJ-NEXT: Export name: funcexp
 READOBJ-NEXT: Symbol: __imp_funcexp
 READOBJ-NEXT: Symbol: funcexp
+READOBJ-NEXT: Symbol: __imp_aux_funcexp
+READOBJ-NEXT: Symbol: #funcexp
+READOBJ-EMPTY:
+READOBJ-NEXT: File: test.dll
+READOBJ-NEXT: Format: COFF-import-file-ARM64EC
+READOBJ-NEXT: Type: code
+READOBJ-NEXT: Name type: export as
+READOBJ-NEXT: Export name: mangledfunc
+READOBJ-NEXT: Symbol: __imp_mangledfunc
+READOBJ-NEXT: Symbol: mangledfunc
+READOBJ-NEXT: Symbol: __imp_aux_mangledfunc
+READOBJ-NEXT: Symbol: #mangledfunc
+READOBJ-EMPTY:
+READOBJ-NEXT: File: test.dll
+READOBJ-NEXT: Format: COFF-import-file-ARM64EC
+READOBJ-NEXT: Type: code
+READOBJ-NEXT: Name type: export as
+READOBJ-NEXT: Export name: ?test_cpp_func@@YAHPEAX@Z
+READOBJ-NEXT: Symbol: __imp_?test_cpp_func@@YAHPEAX@Z
+READOBJ-NEXT: Symbol: ?test_cpp_func@@YAHPEAX@Z
+READOBJ-NEXT: Symbol: __imp_aux_?test_cpp_func@@YAHPEAX@Z
+READOBJ-NEXT: Symbol: ?test_cpp_func@@$$hYAHPEAX@Z
+READOBJ-EMPTY:
+READOBJ-NEXT: File: test.dll
+READOBJ-NEXT: Format: COFF-import-file-ARM64EC
+READOBJ-NEXT: Type: code
+READOBJ-NEXT: Name type: export as
+READOBJ-NEXT: Export name: expname
+READOBJ-NEXT: Symbol: __imp_expname
+READOBJ-NEXT: Symbol: expname
+READOBJ-NEXT: Symbol: __imp_aux_expname
+READOBJ-NEXT: Symbol: #expname
 READOBJ-EMPTY:
 READOBJ-NEXT: File: test.dll
 READOBJ-NEXT: Format: COFF-import-file-ARM64EC
 READOBJ-NEXT: Type: data
 READOBJ-NEXT: Name type: name
+READOBJ-NEXT: Export name: dataexp
 READOBJ-NEXT: Symbol: __imp_dataexp
 
 Creating a new lib containing the existing lib:
@@ -53,4 +104,7 @@ RUN: llvm-nm --print-armap test2.lib | FileCheck -check-prefix=ARMAP %s
 LIBRARY test.dll
 EXPORTS
     funcexp
+    #mangledfunc
+    ?test_cpp_func@@YAHPEAX@Z
+    expname=impname
     dataexp DATA
diff --git a/llvm/test/tools/llvm-readobj/COFF/file-headers.test b/llvm/test/tools/llvm-readobj/COFF/file-headers.test
index b83a6cf5b972b3..32f39e196b0001 100644
--- a/llvm/test/tools/llvm-readobj/COFF/file-headers.test
+++ b/llvm/test/tools/llvm-readobj/COFF/file-headers.test
@@ -323,6 +323,7 @@ symbols:
 #      IMPORTLIB:Format: COFF-import-file-i386
 # IMPORTLIB-NEXT:Type: code
 # IMPORTLIB-NEXT:Name type: noprefix
+# IMPORTLIB-NEXT:Export name: func
 # IMPORTLIB-NEXT:Symbol: __imp__func
 # IMPORTLIB-NEXT:Symbol: _func
 # IMPORTLIB-NOT:{{.}}
diff --git a/llvm/tools/llvm-readobj/COFFImportDumper.cpp b/llvm/tools/llvm-readobj/COFFImportDumper.cpp
index 8aedc310ae3a9f..0ab2a17655653e 100644
--- a/llvm/tools/llvm-readobj/COFFImportDumper.cpp
+++ b/llvm/tools/llvm-readobj/COFFImportDumper.cpp
@@ -45,8 +45,14 @@ void dumpCOFFImportFile(const COFFImportFile *File, ScopedPrinter &Writer) {
   case COFF::IMPORT_NAME_UNDECORATE:
     Writer.printString("Name type", "undecorate");
     break;
+  case COFF::IMPORT_NAME_EXPORTAS:
+    Writer.printString("Name type", "export as");
+    break;
   }
 
+  if (H->getNameType() != COFF::IMPORT_ORDINAL)
+    Writer.printString("Export name", File->getExportName());
+
   for (const object::BasicSymbolRef &Sym : File->symbols()) {
     raw_ostream &OS = Writer.startLine();
     OS << "Symbol: ";