[clang] [Clang][AArch64] Define x86_64 macros for ARM64EC targets (PR #65420)

[Saleem Abdulrasool via cfe-commits]

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@@ -131,3 +144,20 @@
 // CHECK-ARM64-MINGW: #define _WIN64 1
 // CHECK-ARM64-MINGW: #define __GCC_ASM_FLAG_OUTPUTS__ 1
 // CHECK-ARM64-MINGW: #define __aarch64__ 1
+
+// RUN: %clang_cc1 -triple arm64ec-windows-gnu %s -E -dM -o - \
+// RUN:   | FileCheck -match-full-lines %s --check-prefix=CHECK-ARM64EC-MINGW
+
+// CHECK-ARM64EC-MINGW-NOT: #define _M_ARM64EC 1
+// CHECK-ARM64EC-MINGW: #define WIN32 1
+// CHECK-ARM64EC-MINGW: #define WIN64 1
+// CHECK-ARM64EC-MINGW: #define WINNT 1
+// CHECK-ARM64EC-MINGW: #define _WIN32 1
+// CHECK-ARM64EC-MINGW: #define _WIN64 1
+// CHECK-ARM64EC-MINGW: #define __GCC_ASM_FLAG_OUTPUTS__ 1
+// CHECK-ARM64EC-MINGW-NOT: #define __aarch64__ 1
+// CHECK-ARM64EC-MINGW: #define __amd64 1
+// CHECK-ARM64EC-MINGW: #define __amd64__ 1
+// CHECK-ARM64EC-MINGW: #define __arm64ec__ 1
+// CHECK-ARM64EC-MINGW: #define __x86_64 1
+// CHECK-ARM64EC-MINGW: #define __x86_64__ 1
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compnerd wrote:

Missing trailing new line

https://github.com/llvm/llvm-project/pull/65420