From e751ea1b0da3db914e466405009eff0bc317e698 Mon Sep 17 00:00:00 2001
From: Andrei Pangin <noreply@pangin.pro>
Date: Tue, 6 Feb 2024 02:37:28 +0000
Subject: [PATCH] #886: Support cstack=vm for slowdebug JVM

---
 src/vmStructs.cpp | 7 ++++++-
 src/vmStructs.h   | 1 +
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/vmStructs.cpp b/src/vmStructs.cpp
index 7da31eeb..55e36098 100644
--- a/src/vmStructs.cpp
+++ b/src/vmStructs.cpp
@@ -61,6 +61,7 @@ int VMStructs::_constmethod_constants_offset = -1;
 int VMStructs::_constmethod_idnum_offset = -1;
 int VMStructs::_constmethod_size = -1;
 int VMStructs::_pool_holder_offset = -1;
+int VMStructs::_array_len_offset = 0;
 int VMStructs::_array_data_offset = -1;
 int VMStructs::_code_heap_memory_offset = -1;
 int VMStructs::_code_heap_segmap_offset = -1;
@@ -321,6 +322,10 @@ void VMStructs::initOffsets() {
                 if (strcmp(field, "_call_stub_return_address") == 0) {
                     _call_stub_return_addr = *(const void***)(entry + address_offset);
                 }
+            } else if (strcmp(type, "GrowableArrayBase") == 0 || strcmp(type, "GenericGrowableArray") == 0) {
+                if (strcmp(field, "_len") == 0) {
+                    _array_len_offset = *(int*)(entry + offset_offset);
+                }
             } else if (strcmp(type, "GrowableArray<int>") == 0) {
                 if (strcmp(field, "_data") == 0) {
                     _array_data_offset = *(int*)(entry + offset_offset);
@@ -458,7 +463,7 @@ void VMStructs::resolveOffsets() {
 
     if (_code_heap_addr != NULL && _code_heap_low_addr != NULL && _code_heap_high_addr != NULL) {
         char* code_heaps = *_code_heap_addr;
-        unsigned int code_heap_count = *(unsigned int*)code_heaps;
+        unsigned int code_heap_count = *(unsigned int*)(code_heaps + _array_len_offset);
         if (code_heap_count <= 3 && _array_data_offset >= 0) {
             char* code_heap_array = *(char**)(code_heaps + _array_data_offset);
             memcpy(_code_heap, code_heap_array, code_heap_count * sizeof(_code_heap[0]));
diff --git a/src/vmStructs.h b/src/vmStructs.h
index c051283b..38131780 100644
--- a/src/vmStructs.h
+++ b/src/vmStructs.h
@@ -66,6 +66,7 @@ class VMStructs {
     static int _constmethod_idnum_offset;
     static int _constmethod_size;
     static int _pool_holder_offset;
+    static int _array_len_offset;
     static int _array_data_offset;
     static int _code_heap_memory_offset;
     static int _code_heap_segmap_offset;