improve instrumentation for memory leak detection

samuelsadok · Jul 6, 2022 · 40979dc · 40979dc
1 parent b23264e
commit 40979dc
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Showing 4 changed files with 69 additions and 20 deletions.
diff --git a/cpp/README.md b/cpp/README.md
@@ -98,3 +98,12 @@ To compile your application you need to link against the libfibre binary (`-L/pa
  - Fibre currently targets C++11 to maximize compatibility with other projects
  - Notes on platform independent programming:
    - Don't use the keyword `interface` (defined as a macro on Windows in `rpc.h`)
+
+# Debugging Memory Leaks in WASM
+
+This works only in JS, not in dart:
+
+- Add `-fsanitize=leak` to CFLAGS
+- Add `-sINITIAL_MEMORY=104857600` to LDFLAGS
+- Compile
+- In example.html press "Leak Check"
diff --git a/cpp/libfibre.cpp b/cpp/libfibre.cpp
@@ -637,3 +637,27 @@ void libfibre_run_tasks(LibFibreCtx* ctx, LibFibreTask* tasks, size_t n_tasks, L
     *out_tasks = ctx->shadow_task_queue.data();
     *n_out_tasks = ctx->shadow_task_queue.size();
 }
+
+
+extern "C" {
+#if defined(__has_feature)
+#  if __has_feature(address_sanitizer)
+#    define LEAK_CHECK 1
+#  else
+#    define LEAK_CHECK 0
+#  endif
+#else
+#  define LEAK_CHECK 0
+#endif
+
+#if LEAK_CHECK
+#include <sanitizer/lsan_interface.h>
+FIBRE_PUBLIC void do_leak_check() {
+    __lsan_do_recoverable_leak_check();
+}
+#else
+FIBRE_PUBLIC int do_leak_check() {
+    return 0;
+}
+#endif
+}
diff --git a/js/example.html b/js/example.html
@@ -7,6 +7,7 @@
     <body>
         <h1 id="statusText">not connected</h1>
         <button id="connectBtn" disabled>Connect...</button>
+        <button id="leakBtn" disabled>Leak check</button>
         <script type="module">
             import { fibreOpen } from './fibre.js';
 
@@ -27,6 +28,15 @@ <h1 id="statusText">not connected</h1>
 
                 document.getElementById("connectBtn").onclick = showDialog;
                 document.getElementById("connectBtn").removeAttribute('disabled');
+
+                document.getElementById("leakBtn").onclick = (obj) => {
+                    domain._libfibre.wasm.Module._do_leak_check();
+
+                    const addr = domain._libfibre.wasm.Module._malloc(1000);
+                    console.log("got addr", addr)
+                    domain._libfibre.wasm.Module._free(addr);
+                };
+                document.getElementById("leakBtn").removeAttribute('disabled');
             });
         </script>
     </body>

diff --git a/js/fibre.js b/js/fibre.js
@@ -910,28 +910,34 @@ class Domain {
     }
 }
 
-export function fibreOpen(log_verbosity = 5) {
+export function fibreOpen(log_verbosity = 3) {
     return new Promise(async (resolve) => {
         let Module = {
-            instantiateWasm: async (info, receiveInstance) => {
-                const isWebpack = typeof __webpack_require__ === 'function';
-                const wasmPath = isWebpack ? (await import("!!file-loader!./libfibre-wasm.wasm")).default
-                    : "./libfibre-wasm.wasm";
-
-                let result;
-                if (typeof navigator === 'object') {
-                    // Running in browser
-                    const response = fetch(wasmPath, { credentials: 'same-origin' });
-                    result = await WebAssembly.instantiateStreaming(response, info);
-                } else {
-                    // Running in bare NodeJS
-                    const fsPromises = (await import('fs/promises')).default;
-                    const response = await fsPromises.readFile('/Data/Projects/fibre/js/libfibre-wasm.wasm');
-                    result = await WebAssembly.instantiate(response, info);
-                }
-                receiveInstance(result['instance']);
-                return {};
-            }
+//            instantiateWasm: async (info, receiveInstance) => {
+//                const isWebpack = typeof __webpack_require__ === 'function';
+//                const wasmPath = isWebpack ? (await import("!!file-loader!./libfibre-wasm.wasm")).default
+//                    : "./libfibre-wasm.wasm";
+//
+//                let instantiationResult;
+//                var arrayBufferResult;
+//                if (typeof navigator === 'object') {
+//                    // Running in browser
+//                    const response = fetch(wasmPath, { credentials: 'same-origin' });
+//                    arrayBufferResult = (await response).clone().arrayBuffer();
+//                    instantiationResult = await WebAssembly.instantiateStreaming(response, info);
+//                    console.log(instantiationResult);
+//                    //arrayBufferResult = (await response).clone().arrayBuffer();
+//                } else {
+//                    // Running in bare NodeJS
+//                    const fsPromises = (await import('fs/promises')).default;
+//                    const response = await fsPromises.readFile('/Data/Projects/fibre/js/libfibre-wasm.wasm');
+//                    instantiationResult = await WebAssembly.instantiate(response, info);
+//                }
+//
+//                //wasmOffsetConverter = new WasmOffsetConverter(new Uint8Array(arrayBufferResult), instantiationResult.module);
+//                receiveInstance(instantiationResult['instance'], null, arrayBufferResult);
+//                return {};
+//            }
         };
         Module = await wasm(Module);
         await Module.ready;