Alexandre Julliard : ntdll: Ignore end_c when processing ARM64 unwind codes.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 1abebca6dc024505a72bd564c6e998107102c1c4
URL:    https://gitlab.winehq.org/wine/wine/-/commit/1abebca6dc024505a72bd564c6e9981...

Author: Alexandre Julliard <julliard(a)winehq.org>
Date:   Thu Feb 15 16:29:03 2024 +0100

ntdll: Ignore end_c when processing ARM64 unwind codes.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=55584

---

 dlls/ntdll/tests/exception.c | 41 +++++++++++++++++++++++++++++++++++++++++
 dlls/ntdll/unwind.c          |  4 ++--
 2 files changed, 43 insertions(+), 2 deletions(-)

diff --git a/dlls/ntdll/tests/exception.c b/dlls/ntdll/tests/exception.c
index 789a954cbe0..518b15f7821 100644
--- a/dlls/ntdll/tests/exception.c
+++ b/dlls/ntdll/tests/exception.c
@@ -8952,6 +8952,46 @@ static void test_virtual_unwind(void)
         { 0x1c,  0xa0,  0,     0xa8,    0x0b0, TRUE, { {d6, 0x00}, {d7, 0x10}, {d8, 0x20}, {d9, 0x30}, {d10, 0x40}, {d11, 0x50}, {d12, 0x60}, {d13, 0x70}, {d14, 0x80}, {d15, 0x90}, {lr, 0xa8}, {x29, 0xa0}, {-1,-1} }},
     };
 
+    static const BYTE function_15[] =
+    {
+        0x1f, 0x20, 0x03, 0xd5,   /* 00: nop */
+        0x1f, 0x20, 0x03, 0xd5,   /* 04: nop */
+        0x1f, 0x20, 0x03, 0xd5,   /* 08: nop */
+        0x1f, 0x20, 0x03, 0xd5,   /* 0c: nop */
+        0x1f, 0x20, 0x03, 0xd5,   /* 10: nop */
+        0xc0, 0x03, 0x5f, 0xd6,   /* 14: ret */
+    };
+
+    static const DWORD unwind_info_15_header =
+        (sizeof(function_15)/4) | /* function length */
+        (0 << 20) | /* X */
+        (0 << 21) | /* E */
+        (0 << 22) | /* epilog */
+        (2 << 27);  /* codes */
+
+    static const BYTE unwind_info_15[] =
+    {
+        DW(unwind_info_15_header),
+        UWOP_END_C,
+        UWOP_SET_FP,              /* mov x29, sp */
+        UWOP_SAVE_REGP(19, 0x10), /* stp r19, r20, [sp, #0x10] */
+        UWOP_SAVE_FPLR_X(0x20),   /* stp r29, lr, [sp,-#0x20]! */
+        UWOP_END,
+        UWOP_NOP,                 /* padding */
+        UWOP_NOP,                 /* padding */
+    };
+
+    static const struct results results_15[] =
+    {
+      /* offset  fp    handler  pc      frame offset  registers */
+        { 0x00,  0x00,  0,     0x08,    0x020, TRUE, { {x29, 0x00}, {lr, 0x08}, {x19,0x10}, {x20,0x18}, {-1,-1} }},
+        { 0x04,  0x00,  0,     0x08,    0x020, TRUE, { {x29, 0x00}, {lr, 0x08}, {x19,0x10}, {x20,0x18}, {-1,-1} }},
+        { 0x08,  0x00,  0,     0x08,    0x020, TRUE, { {x29, 0x00}, {lr, 0x08}, {x19,0x10}, {x20,0x18}, {-1,-1} }},
+        { 0x0c,  0x00,  0,     0x08,    0x020, TRUE, { {x29, 0x00}, {lr, 0x08}, {x19,0x10}, {x20,0x18}, {-1,-1} }},
+        { 0x10,  0x00,  0,     0x08,    0x020, TRUE, { {x29, 0x00}, {lr, 0x08}, {x19,0x10}, {x20,0x18}, {-1,-1} }},
+        { 0x14,  0x00,  0,     0x08,    0x020, TRUE, { {x29, 0x00}, {lr, 0x08}, {x19,0x10}, {x20,0x18}, {-1,-1} }},
+    };
+
     static const struct unwind_test tests[] =
     {
 #define TEST(func, unwind, unwind_packed, results) \
@@ -8971,6 +9011,7 @@ static void test_virtual_unwind(void)
         TEST(function_12, unwind_info_12, 1, results_12),
         TEST(function_13, unwind_info_13, 1, results_13),
         TEST(function_14, unwind_info_14, 0, results_14),
+        TEST(function_15, unwind_info_15, 0, results_15),
 #undef TEST
     };
     unsigned int i;
diff --git a/dlls/ntdll/unwind.c b/dlls/ntdll/unwind.c
index 4cc304b63ef..270410adf82 100644
--- a/dlls/ntdll/unwind.c
+++ b/dlls/ntdll/unwind.c
@@ -392,7 +392,7 @@ static void process_unwind_codes( BYTE *ptr, BYTE *end, ARM64_NT_CONTEXT *contex
     /* skip codes */
     while (ptr < end && skip)
     {
-        if (*ptr == 0xe4 || *ptr == 0xe5) break;
+        if (*ptr == 0xe4) break;
         ptr += unwind_code_len[*ptr];
         skip--;
     }
@@ -448,7 +448,7 @@ static void process_unwind_codes( BYTE *ptr, BYTE *end, ARM64_NT_CONTEXT *contex
         else if (*ptr == 0xe4)  /* end */
             break;
         else if (*ptr == 0xe5)  /* end_c */
-            break;
+            /* ignore */;
         else if (*ptr == 0xe6)  /* save_next */
         {
             save_next += 2;