Index: COFF/Config.h
===================================================================
--- COFF/Config.h
+++ COFF/Config.h
@@ -31,6 +31,7 @@
 
 // Short aliases.
 static const auto AMD64 = llvm::COFF::IMAGE_FILE_MACHINE_AMD64;
+static const auto ARM64 = llvm::COFF::IMAGE_FILE_MACHINE_ARM64;
 static const auto ARMNT = llvm::COFF::IMAGE_FILE_MACHINE_ARMNT;
 static const auto I386 = llvm::COFF::IMAGE_FILE_MACHINE_I386;
 
@@ -73,7 +74,7 @@
 // Global configuration.
 struct Configuration {
   enum ManifestKind { SideBySide, Embed, No };
-  bool is64() { return Machine == AMD64; }
+  bool is64() { return Machine == AMD64 || Machine == ARM64; }
 
   llvm::COFF::MachineTypes Machine = IMAGE_FILE_MACHINE_UNKNOWN;
   bool Verbose = false;
Index: test/COFF/arm64-magic.yaml
===================================================================
--- /dev/null
+++ test/COFF/arm64-magic.yaml
@@ -0,0 +1,35 @@
+# RUN: yaml2obj < %s > %t.obj
+# RUN: lld-link /out:%t.exe /entry:mainCRTStartup /subsystem:console %t.obj
+# RUN: llvm-readobj -file-headers %t.exe | FileCheck %s
+
+# CHECK: Magic: 0x20B
+
+--- !COFF
+header:
+  Machine:         IMAGE_FILE_MACHINE_ARM64
+  Characteristics: []
+sections:
+  - Name:            .text
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_PURGEABLE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       4
+    SectionData:     'e0031f2ac0035fd6'
+symbols:
+  - Name:            .text
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          8
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          1
+  - Name:            mainCRTStartup
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_FUNCTION
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+...