From bb5cdbd1230394ad1611ae03b3c5ac9d0d157994 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E8=B5=B5=E6=80=A1=E7=84=B6?= <yiranzhao@yandex.com>
Date: Sat, 18 Apr 2026 11:01:27 +0800
Subject: [PATCH] add ARM64 decoder

---
 un7zip/src/main/cpp/src/7zDec.c |  3 ++
 un7zip/src/main/cpp/src/Bra.c   | 59 +++++++++++++++++++++++++++++++++
 un7zip/src/main/cpp/src/Bra.h   |  1 +
 3 files changed, 63 insertions(+)

diff --git a/un7zip/src/main/cpp/src/7zDec.c b/un7zip/src/main/cpp/src/7zDec.c
index 7c46352..9bbb9c5 100644
--- a/un7zip/src/main/cpp/src/7zDec.c
+++ b/un7zip/src/main/cpp/src/7zDec.c
@@ -31,6 +31,7 @@
 #define k_ARM   0x3030501
 #define k_ARMT  0x3030701
 #define k_SPARC 0x3030805
+#define k_ARM64 0xA
 
 
 #ifdef _7ZIP_PPMD_SUPPPORT
@@ -333,6 +334,7 @@ static SRes CheckSupportedFolder(const CSzFolder *f)
       case k_SPARC:
       case k_ARM:
       case k_ARMT:
+      case k_ARM64:
         break;
       default:
         return SZ_ERROR_UNSUPPORTED;
@@ -532,6 +534,7 @@ static SRes SzFolder_Decode2(const CSzFolder *folder,
           CASE_BRA_CONV(SPARC)
           CASE_BRA_CONV(ARM)
           CASE_BRA_CONV(ARMT)
+          CASE_BRA_CONV(ARM64)
           default:
             return SZ_ERROR_UNSUPPORTED;
         }
diff --git a/un7zip/src/main/cpp/src/Bra.c b/un7zip/src/main/cpp/src/Bra.c
index aed17e3..c3e11cd 100644
--- a/un7zip/src/main/cpp/src/Bra.c
+++ b/un7zip/src/main/cpp/src/Bra.c
@@ -61,6 +61,65 @@ SizeT ARM_Convert(Byte *data, SizeT size, UInt32 ip, int encoding)
 }
 
 
+SizeT ARM64_Convert(Byte *data, SizeT size, UInt32 ip, int encoding)
+{
+  /*
+   * ARM64 Branch/Call/Jump (BCJ) filter decoder
+   * Adapted from xz-embedded project by Lasse Collin and Igor Pavlov
+   * This file has been put into the public domain.
+   */
+  
+  SizeT i;
+  UInt32 instr;
+  UInt32 addr;
+  
+  size &= ~(SizeT)3;  /* Align to 4 bytes */
+  
+  for (i = 0; i + 4 <= size; i += 4)
+  {
+    instr = GetUi32(data + i);
+    
+    if ((instr >> 26) == 0x25)
+    {
+      /* BL (Branch with Link) instruction */
+      addr = instr & 0x03FFFFFF;
+      
+      if (encoding)
+        addr += (ip + (UInt32)i) >> 2;
+      else
+        addr -= (ip + (UInt32)i) >> 2;
+      
+      instr = 0x94000000 | (addr & 0x03FFFFFF);
+      
+      SetUi32(data + i, instr);
+    }
+    else if ((instr & 0x9F000000) == 0x90000000)
+    {
+      /* ADRP (Address of a Page) instruction */
+      addr = ((instr >> 29) & 3) | ((instr >> 3) & 0x1FFFFC);
+      
+      /* Only convert values in the range +/-512 MiB */
+      if ((addr + 0x020000) & 0x1C0000)
+        continue;
+      
+      if (encoding)
+        addr += (ip + (UInt32)i) >> 12;
+      else
+        addr -= (ip + (UInt32)i) >> 12;
+      
+      instr &= 0x9000001F;
+      instr |= (addr & 3) << 29;
+      instr |= (addr & 0x03FFFC) << 3;
+      instr |= (0U - (addr & 0x020000)) & 0xE00000;
+      
+      SetUi32(data + i, instr);
+    }
+  }
+  
+  return i;
+}
+
+
 SizeT ARMT_Convert(Byte *data, SizeT size, UInt32 ip, int encoding)
 {
   Byte *p;
diff --git a/un7zip/src/main/cpp/src/Bra.h b/un7zip/src/main/cpp/src/Bra.h
index 855e37a..77bb84c 100644
--- a/un7zip/src/main/cpp/src/Bra.h
+++ b/un7zip/src/main/cpp/src/Bra.h
@@ -58,6 +58,7 @@ SizeT ARMT_Convert(Byte *data, SizeT size, UInt32 ip, int encoding);
 SizeT PPC_Convert(Byte *data, SizeT size, UInt32 ip, int encoding);
 SizeT SPARC_Convert(Byte *data, SizeT size, UInt32 ip, int encoding);
 SizeT IA64_Convert(Byte *data, SizeT size, UInt32 ip, int encoding);
+SizeT ARM64_Convert(Byte *data, SizeT size, UInt32 ip, int encoding);
 
 EXTERN_C_END