AArch64 compatibility header (#2321)

.github/workflows/CITest.yml

@@ -100,6 +100,12 @@ jobs:
         cp libcapstone.* ../tests/
         cp test_* ../tests/
 
+    - name: "Compatibility header test build"
+      run: |
+        cd "$(git rev-parse --show-toplevel)/suite/auto-sync/c_tests/"
+        clang -lcapstone  src/test_arm64_compatibility_header.c -o test_arm64_compatibility_header
+        ./test_arm64_compatibility_header
+
     - name: cstool - reaches disassembler engine
       run: |
         sh suite/run_invalid_cstool.sh

CMakeLists.txt

@@ -157,6 +157,7 @@ set(HEADERS_ENGINE
 
 set(HEADERS_COMMON
     include/capstone/aarch64.h
+    include/capstone/arm64.h
     include/capstone/arm.h
     include/capstone/capstone.h
     include/capstone/cs_operand.h

docs/cs_v6_release_guide.md

@@ -84,16 +84,30 @@ With all that said, we hope you enjoy the new release!
 
 `ARM64` was everywhere renamed to `AArch64`. This is a necessity to ensure that the update scripts stay reasonably simple.
 Capstone was very inconsistent with the naming before (sometimes `AArch64` sometimes `ARM64`).
-Because Capstone uses a huge amount of LLVM code, we renamed everything to `AArch64`. This reduces complexity enormously.
+Because Capstone uses a huge amount of LLVM code, we renamed everything to `AArch64`. This reduces complexity enormously because it follows the naming of LLVM.
 
-Because this would completely break maintaining Capstone `v6` and `pre-v6` in a project, we added macros for meta-programming.
+Because this would completely break maintaining Capstone `v6` and `pre-v6` in a project, we added two solutions:
 
-If you need to support the previous version of Capstone as well, you can use those macros (see below helper scripts).
-Also, your can exclude/include code by checking `CS_NEXT_VERSION < 6`.
+1. Make `arm64.h` a compatibility header which merely maps every member to the one in the `aarch64.h` header.
+2. Macros for meta-programming which select the right name.
 
-The following `sed` commands in a sh script should ease the renaming from `ARM64` to `AArch64` a lot.
+We will continue to maintain both solutions.
+So if you need to support the previous version of Capstone as well, you can use either of the solutions.
 
-Replacing with version sensitive macros:
+_Compatibility header_
+
+If you want to use the compatibility header and stick with the `ARM64` naming, you can define `CAPSTONE_AARCH64_COMPAT_HEADER` before including `capstone.h`.
+
+```c
+#define CAPSTONE_AARCH64_COMPAT_HEADER
+#include <capstone/capstone.h>
+
+// Your code...
+```
+
+_Meta programming macros_
+
+The following `sed` commands in a sh script should ease the replacement of `ARM64` with the macros a lot.
 
 ```sh
 #!/bin/sh