Add architecture diagram for wasm globals and classic-interp stack frame (#2058)

Author: xwang98

README.md

@@ -70,8 +70,8 @@ The following platforms are supported, click each link below for how to build iw
 
 
 ### Performance and memory
-- [Blog: Understand WAMR heap](https://bytecodealliance.github.io/wamr.dev/blog/understand-the-wamr-heap/)
-- [Blog: Understand WAMR stacks](https://bytecodealliance.github.io/wamr.dev/blog/understand-the-wamr-stacks/)
+- [Blog: The WAMR memory model](https://bytecodealliance.github.io/wamr.dev/blog/the-wamr-memory-model/)
+- [Blog: Understand WAMR heaps](https://bytecodealliance.github.io/wamr.dev/blog/understand-the-wamr-heaps/) and [stacks](https://bytecodealliance.github.io/wamr.dev/blog/understand-the-wamr-stacks/)
 - [Blog: Introduction to WAMR running modes](https://bytecodealliance.github.io/wamr.dev/blog/introduction-to-wamr-running-modes/)
 - [Memory usage tunning](./doc/memory_tune.md): the memory model and how to tune the memory usage
 - [Memory usage profiling](./doc/build_wamr.md#enable-memory-profiling-experiment): how to profile the memory usage

core/iwasm/README.md

@@ -6,3 +6,9 @@
 
 ## Exports
 - [Wasm export architecture](./doc/wasm_exports.MD)
+
+## globals
+- [Wasm globals architecture](./doc/wasm_globals.MD)
+
+## classic interpreter
+- [classic interpreter](./doc/classic_interpreter.MD)

core/iwasm/doc/classic_interpreter.MD

@@ -0,0 +1,5 @@
+# Classic interpreter
+
+## stack format
+
+![](./images/stack_format_ci.svg)