Revert "lldb_function_to_function_dbi: A hack to avoid crashing on C++ methods (#3190)" (#3281)

This reverts commit 0e8d949440441b2b18d166934747d595a8f696ee.

Because it doesn't make much sense anymore after we disabled debug info
processing on C++ functions in:
"aot debug: process lldb_function_to_function_dbi only for C".

core/iwasm/compilation/debug/dwarf_extractor.cpp

@@ -387,27 +387,10 @@ lldb_function_to_function_dbi(const AOTCompContext *comp_ctx,
         LLVMDIBuilderCreateExpression(DIB, NULL, 0);
     auto variable_list =
         function.GetBlock().GetVariables(extractor->target, true, false, false);
-    unsigned int variable_offset = 0;
     if (num_function_args != variable_list.GetSize()) {
-        // A hack to detect C++ "this" pointer.
-        //
-        // REVISIT: is there a more reliable way?
-        // At the DWARF level, we can probably look at DW_AT_object_pointer
-        // and DW_AT_artificial. I'm not sure how it can be done via the
-        // LLDB API though.
-        if (num_function_args + 1 == variable_list.GetSize()) {
-            SBValue variable(variable_list.GetValueAtIndex(0));
-            const char *varname = variable.GetName();
-            if (varname != NULL && !strcmp(varname, "this")) {
-                variable_offset = 1;
-            }
-        }
-        if (!variable_offset) {
-            LOG_ERROR("function args number dismatch!:function %s %s value "
-                      "number=%d, function args=%d",
-                      function_name, function.GetMangledName(),
-                      variable_list.GetSize(), num_function_args);
-        }
+        LOG_ERROR(
+            "function args number dismatch!:value number=%d, function args=%d",
+            variable_list.GetSize(), num_function_args);
     }
 
     LLVMMetadataRef ParamLocation = LLVMDIBuilderCreateDebugLocation(
@@ -428,10 +411,9 @@ lldb_function_to_function_dbi(const AOTCompContext *comp_ctx,
     LLVMDIBuilderInsertDbgValueAtEnd(DIB, Param, ParamVar, ParamExpression,
                                      ParamLocation, block_curr);
 
-    for (uint32_t function_arg_idx = 0; function_arg_idx < num_function_args;
-         ++function_arg_idx) {
-        uint32_t variable_idx = variable_offset + function_arg_idx;
-        SBValue variable(variable_list.GetValueAtIndex(variable_idx));
+    for (uint32_t function_arg_idx = 0;
+         function_arg_idx < variable_list.GetSize(); ++function_arg_idx) {
+        SBValue variable(variable_list.GetValueAtIndex(function_arg_idx));
         if (variable.IsValid() && ParamTypes[function_arg_idx + 1] != NULL) {
             SBDeclaration dec(variable.GetDeclaration());
             auto valtype = variable.GetType();
@@ -441,11 +423,12 @@ lldb_function_to_function_dbi(const AOTCompContext *comp_ctx,
             const char *varname = variable.GetName();
             LLVMMetadataRef ParamVar = LLVMDIBuilderCreateParameterVariable(
                 DIB, FunctionMetadata, varname, varname ? strlen(varname) : 0,
-                variable_idx + 1 + 1,
+                function_arg_idx + 1 + 1,
                 File, // starts form 1, and 1 is exenv,
                 dec.GetLine(), ParamTypes[function_arg_idx + 1], true,
                 LLVMDIFlagZero);
-            LLVMValueRef Param = LLVMGetParam(func_ctx->func, variable_idx + 1);
+            LLVMValueRef Param =
+                LLVMGetParam(func_ctx->func, function_arg_idx + 1);
             LLVMDIBuilderInsertDbgValueAtEnd(DIB, Param, ParamVar,
                                              ParamExpression, ParamLocation,
                                              block_curr);