Index: ELF/ScriptParser.cpp
===================================================================
--- ELF/ScriptParser.cpp
+++ ELF/ScriptParser.cpp
@@ -389,6 +389,7 @@
       .Case("elf32-iamcu", {ELF32LEKind, EM_IAMCU})
       .Case("elf32-littlearm", {ELF32LEKind, EM_ARM})
       .Case("elf32-x86-64", {ELF32LEKind, EM_X86_64})
+      .Case("elf64-aarch64", {ELF64LEKind, EM_AARCH64})
       .Case("elf64-littleaarch64", {ELF64LEKind, EM_AARCH64})
       .Case("elf64-powerpc", {ELF64BEKind, EM_PPC64})
       .Case("elf64-powerpcle", {ELF64LEKind, EM_PPC64})
@@ -407,11 +408,14 @@
 void ScriptParser::readOutputFormat() {
   expect("(");
 
-  StringRef S = unquote(next());
+  StringRef Name = unquote(next());
+  StringRef S = Name;
+  if (S.consume_back("-freebsd"))
+    Config->OSABI = ELFOSABI_FREEBSD;
 
   std::tie(Config->EKind, Config->EMachine) = parseBfdName(S);
   if (Config->EMachine == EM_NONE)
-    setError("unknown output format name: " + S);
+    setError("unknown output format name: " + Name);
   if (S == "elf32-ntradlittlemips" || S == "elf32-ntradbigmips")
     Config->MipsN32Abi = true;
 
Index: test/ELF/emulation-aarch64.s
===================================================================
--- test/ELF/emulation-aarch64.s
+++ test/ELF/emulation-aarch64.s
@@ -30,5 +30,28 @@
 # AARCH64-NEXT:   Flags [ (0x0)
 # AARCH64-NEXT:   ]
 
+# RUN: llvm-mc -filetype=obj -triple=aarch64-unknown-freebsd %s -o %taarch64fbsd
+# RUN: echo 'OUTPUT_FORMAT(elf64-aarch64-freebsd)' > %taarch64fbsd.script
+# RUN: ld.lld %taarch64fbsd.script %taarch64fbsd -o %t2aarch64fbsd
+# RUN: llvm-readobj -file-headers %t2aarch64fbsd | FileCheck --check-prefix=AARCH64-FBSD %s
+# AARCH64-FBSD:      ElfHeader {
+# AARCH64-FBSD-NEXT:   Ident {
+# AARCH64-FBSD-NEXT:     Magic: (7F 45 4C 46)
+# AARCH64-FBSD-NEXT:     Class: 64-bit (0x2)
+# AARCH64-FBSD-NEXT:     DataEncoding: LittleEndian (0x1)
+# AARCH64-FBSD-NEXT:     FileVersion: 1
+# AARCH64-FBSD-NEXT:     OS/ABI: FreeBSD (0x9)
+# AARCH64-FBSD-NEXT:     ABIVersion: 0
+# AARCH64-FBSD-NEXT:     Unused: (00 00 00 00 00 00 00)
+# AARCH64-FBSD-NEXT:   }
+# AARCH64-FBSD-NEXT:   Type: Executable (0x2)
+# AARCH64-FBSD-NEXT:   Machine: EM_AARCH64 (0xB7)
+# AARCH64-FBSD-NEXT:   Version: 1
+# AARCH64-FBSD-NEXT:   Entry:
+# AARCH64-FBSD-NEXT:   ProgramHeaderOffset: 0x40
+# AARCH64-FBSD-NEXT:   SectionHeaderOffset:
+# AARCH64-FBSD-NEXT:   Flags [ (0x0)
+# AARCH64-FBSD-NEXT:   ]
+
 .globl _start
 _start:
Index: test/ELF/emulation-ppc.s
===================================================================
--- test/ELF/emulation-ppc.s
+++ test/ELF/emulation-ppc.s
@@ -35,6 +35,38 @@
 # PPC64-NEXT:   StringTableSectionIndex:
 # PPC64-NEXT: }
 
+# RUN: llvm-mc -filetype=obj -triple=powerpc64-unknown-freebsd %s -o %tppc64fbsd
+# RUN: echo 'OUTPUT_FORMAT(elf64-powerpc-freebsd)' > %tppc64fbsd.script
+# RUN: ld.lld %tppc64fbsd.script  %tppc64fbsd -o %t2ppc64fbsd
+# RUN: llvm-readobj -file-headers %t2ppc64fbsd | FileCheck --check-prefix=PPC64-FBSD %s
+
+# PPC64-FBSD:      ElfHeader {
+# PPC64-FBSD-NEXT:   Ident {
+# PPC64-FBSD-NEXT:     Magic: (7F 45 4C 46)
+# PPC64-FBSD-NEXT:     Class: 64-bit (0x2)
+# PPC64-FBSD-NEXT:     DataEncoding: BigEndian (0x2)
+# PPC64-FBSD-NEXT:     FileVersion: 1
+# PPC64-FBSD-NEXT:     OS/ABI: FreeBSD (0x9)
+# PPC64-FBSD-NEXT:     ABIVersion: 0
+# PPC64-FBSD-NEXT:     Unused: (00 00 00 00 00 00 00)
+# PPC64-FBSD-NEXT:   }
+# PPC64-FBSD-NEXT:   Type: Executable (0x2)
+# PPC64-FBSD-NEXT:   Machine: EM_PPC64 (0x15)
+# PPC64-FBSD-NEXT:   Version: 1
+# PPC64-FBSD-NEXT:   Entry:
+# PPC64-FBSD-NEXT:   ProgramHeaderOffset: 0x40
+# PPC64-FBSD-NEXT:   SectionHeaderOffset:
+# PPC64-FBSD-NEXT:   Flags [ (0x2)
+# PPC64-FBSD-NEXT:     0x2
+# PPC64-FBSD-NEXT:   ]
+# PPC64-FBSD-NEXT:   HeaderSize: 64
+# PPC64-FBSD-NEXT:   ProgramHeaderEntrySize: 56
+# PPC64-FBSD-NEXT:   ProgramHeaderCount:
+# PPC64-FBSD-NEXT:   SectionHeaderEntrySize: 64
+# PPC64-FBSD-NEXT:   SectionHeaderCount:
+# PPC64-FBSD-NEXT:   StringTableSectionIndex:
+# PPC64-FBSD-NEXT: }
+
 # RUN: llvm-mc -filetype=obj -triple=powerpc64le-unknown-linux %s -o %tppc64le
 # RUN: ld.lld -m elf64lppc %tppc64le -o %t2ppc64le
 # RUN: llvm-readobj -file-headers %t2ppc64le | FileCheck --check-prefix=PPC64LE %s
Index: test/ELF/emulation-x86.s
===================================================================
--- test/ELF/emulation-x86.s
+++ test/ELF/emulation-x86.s
@@ -7,6 +7,9 @@
 # RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t.sysv
 # RUN: ld.lld -m elf_amd64_fbsd %t.sysv -o %t.freebsd
 # RUN: llvm-readobj -file-headers %t.freebsd | FileCheck --check-prefix=AMD64 %s
+# RUN: echo 'OUTPUT_FORMAT(elf64-x86-64-freebsd)' > %t4x64.script
+# RUN: ld.lld %t4x64.script %tx64 -o %t4x64
+# RUN: llvm-readobj -file-headers %t4x64 | FileCheck --check-prefix=AMD64 %s
 # AMD64:      ElfHeader {
 # AMD64-NEXT:   Ident {
 # AMD64-NEXT:     Magic: (7F 45 4C 46)
@@ -137,10 +140,13 @@
 # X86-NEXT: }
 
 # RUN: llvm-mc -filetype=obj -triple=i686-unknown-freebsd %s -o %tx86fbsd
-# RUN: ld.lld -m elf_i386_fbsd %tx86fbsd -o %t2x86_fbsd
-# RUN: llvm-readobj -file-headers %t2x86_fbsd | FileCheck --check-prefix=X86FBSD %s
+# RUN: ld.lld -m elf_i386_fbsd %tx86fbsd -o %t2x86fbsd
+# RUN: llvm-readobj -file-headers %t2x86fbsd | FileCheck --check-prefix=X86FBSD %s
 # RUN: ld.lld %tx86fbsd -o %t3x86fbsd
 # RUN: llvm-readobj -file-headers %t3x86fbsd | FileCheck --check-prefix=X86FBSD %s
+# RUN: echo 'OUTPUT_FORMAT(elf32-i386-freebsd)' > %t4x86fbsd.script
+# RUN: ld.lld %t4x86fbsd.script %tx86fbsd -o %t4x86fbsd
+# RUN: llvm-readobj -file-headers %t4x86fbsd | FileCheck --check-prefix=X86FBSD %s
 # X86FBSD:      ElfHeader {
 # X86FBSD-NEXT:   Ident {
 # X86FBSD-NEXT:     Magic: (7F 45 4C 46)