jsifier: Make JS libraries aliases work even when native export exists

embuilder.py

@@ -85,8 +85,11 @@
     'libc++-mt-noexcept',
     'libdlmalloc-mt',
     'libGL-emu',
+    'libGL-emu-webgl2',
     'libGL-mt',
     'libGL-mt-emu',
+    'libGL-mt-emu-webgl2',
+    'libGL-mt-emu-webgl2-ofb',
     'libsockets_proxy',
     'libsockets-mt',
     'crtbegin',

src/jsifier.js

@@ -228,17 +228,12 @@ function ${name}(${args}) {
       // what we just added to the library.
     }
 
-    function addFromLibrary(symbol, dependent) {
+    function addFromLibrary(symbol, dependent, force = false) {
       // dependencies can be JS functions, which we just run
       if (typeof symbol == 'function') {
         return symbol();
       }
 
-      if (symbol in addedLibraryItems) {
-        return;
-      }
-      addedLibraryItems[symbol] = true;
-
       // don't process any special identifiers. These are looked up when
       // processing the base name of the identifier.
       if (isJsLibraryConfigIdentifier(symbol)) {
@@ -257,9 +252,14 @@ function ${name}(${args}) {
 
       // if the function was implemented in compiled code, there is no need to
       // include the js version
-      if (WASM_EXPORTS.has(symbol)) {
+      if (WASM_EXPORTS.has(symbol) && !force) {
+        return;
+      }
+
+      if (symbol in addedLibraryItems) {
         return;
       }
+      addedLibraryItems[symbol] = true;
 
       // This gets set to true in the case of dynamic linking for symbols that
       // are undefined in the main module.  In this case we create a stub that
@@ -334,17 +334,19 @@ function ${name}(${args}) {
           warn(`user library symbol '${symbol}' depends on internal symbol '${dep}'`);
         }
       });
+
       let isFunction = false;
+      let aliasTarget;
 
       if (typeof snippet == 'string') {
         if (snippet[0] != '=') {
-          const target = LibraryManager.library[snippet];
-          if (target) {
-            // Redirection for aliases. We include the parent, and at runtime make ourselves equal to it.
-            // This avoid having duplicate functions with identical content.
-            const redirectedTarget = snippet;
-            deps.push(redirectedTarget);
-            snippet = mangleCSymbolName(redirectedTarget);
+          if (LibraryManager.library[snippet]) {
+            // Redirection for aliases. We include the parent, and at runtime
+            // make ourselves equal to it.  This avoid having duplicate
+            // functions with identical content.
+            aliasTarget = snippet;
+            snippet = mangleCSymbolName(aliasTarget);
+            deps.push(aliasTarget);
           }
         }
       } else if (typeof snippet == 'object') {
@@ -376,7 +378,7 @@ function ${name}(${args}) {
       const deps_list = deps.join("','");
       const identDependents = symbol + `__deps: ['${deps_list}']`;
       function addDependency(dep) {
-        return addFromLibrary(dep, `${identDependents}, referenced by ${dependent}`);
+        return addFromLibrary(dep, `${identDependents}, referenced by ${dependent}`, dep === aliasTarget);
       }
       let contentText;
       if (isFunction) {
@@ -431,8 +433,11 @@ function ${name}(${args}) {
       }
 
       let commentText = '';
+      if (force) {
+        commentText += '/** @suppress {duplicate } */\n'
+      }
       if (LibraryManager.library[symbol + '__docs']) {
-        commentText = LibraryManager.library[symbol + '__docs'] + '\n';
+        commentText += LibraryManager.library[symbol + '__docs'] + '\n';
       }
 
       const depsText = (deps ? deps.map(addDependency).filter((x) => x != '').join('\n') + '\n' : '');

src/parseTools.js

@@ -838,7 +838,7 @@ function hasExportedSymbol(sym) {
 // it is a BigInt. Otherwise, we legalize into pairs of i32s.
 function defineI64Param(name) {
   if (WASM_BIGINT) {
-    return `/** @type {!BigInt} */ ${name}`;
+    return name;
   }
   return `${name}_low, ${name}_high`;
 }

system/lib/gl/webgl2.c

@@ -131,9 +131,10 @@ ASYNC_GL_FUNCTION_5(EM_FUNC_SIG_VIIIII, void, glTexStorage2D, GLenum, GLsizei, G
 ASYNC_GL_FUNCTION_6(EM_FUNC_SIG_VIIIIII, void, glTexStorage3D, GLenum, GLsizei, GLenum, GLsizei, GLsizei, GLsizei);
 VOID_SYNC_GL_FUNCTION_5(EM_FUNC_SIG_VIIIII, void, glGetInternalformativ, GLenum, GLenum, GLenum, GLsizei, GLint *);
 
-#endif // ~__EMSCRIPTEN_PTHREADS__
-
-// Extensions:
+// Extensions that are aliases for the proxying functions defined above.
+// Normally these aliases get defined in library_webgl.js but when building with
+// __EMSCRIPTEN_OFFSCREEN_FRAMEBUFFER__ we want to intercept them in native
+// code and redirect them to thier proxying couterparts.
 GL_APICALL void GL_APIENTRY glVertexAttribDivisorNV(GLuint index, GLuint divisor) { glVertexAttribDivisor(index, divisor); }
 GL_APICALL void GL_APIENTRY glVertexAttribDivisorEXT(GLuint index, GLuint divisor) { glVertexAttribDivisor(index, divisor); }
 GL_APICALL void GL_APIENTRY glVertexAttribDivisorARB(GLuint index, GLuint divisor) { glVertexAttribDivisor(index, divisor); }
@@ -153,6 +154,8 @@ GL_APICALL GLboolean GL_APIENTRY glIsVertexArrayOES(GLuint array) { return glIsV
 GL_APICALL void GL_APIENTRY glDrawBuffersEXT(GLsizei n, const GLenum *bufs) { glDrawBuffers(n, bufs); }
 GL_APICALL void GL_APIENTRY glDrawBuffersWEBGL(GLsizei n, const GLenum *bufs) { glDrawBuffers(n, bufs); }
 
+#endif // ~__EMSCRIPTEN_PTHREADS__) && __EMSCRIPTEN_OFFSCREEN_FRAMEBUFFER__
+
 // Returns a function pointer to the given WebGL 2 extension function, when queried without
 // a GL extension suffix such as "EXT", "OES", or "ANGLE". This function is used by
 // emscripten_GetProcAddress() to implement legacy GL emulation semantics for portability.

system/lib/gl/webgl_internal.h

@@ -7,6 +7,8 @@ EMSCRIPTEN_RESULT emscripten_webgl_do_commit_frame(void);
 EM_BOOL emscripten_supports_offscreencanvas(void);
 void _emscripten_proxied_gl_context_activated_from_main_browser_thread(EMSCRIPTEN_WEBGL_CONTEXT_HANDLE context);
 
+#if defined(__EMSCRIPTEN_PTHREADS__) && defined(__EMSCRIPTEN_OFFSCREEN_FRAMEBUFFER__)
+
 #ifdef EMSCRIPTEN_WEBGL_TRACE
 #define GL_FUNCTION_TRACE(func) printf(#func "\n")
 #else
@@ -52,8 +54,6 @@ void _emscripten_proxied_gl_context_activated_from_main_browser_thread(EMSCRIPTE
 #define VOID_SYNC_GL_FUNCTION_10(sig, ret, functionName, t0, t1, t2, t3, t4, t5, t6, t7, t8, t9) ret functionName(t0 p0, t1 p1, t2 p2, t3 p3, t4 p4, t5 p5, t6 p6, t7 p7, t8 p8, t9 p9) { GL_FUNCTION_TRACE(functionName); if (pthread_getspecific(currentThreadOwnsItsWebGLContext)) emscripten_##functionName(p0, p1, p2, p3, p4, p5, p6, p7, p8, p9); else emscripten_sync_run_in_main_runtime_thread(sig, &emscripten_##functionName, p0, p1, p2, p3, p4, p5, p6, p7, p8, p9); }
 #define VOID_SYNC_GL_FUNCTION_11(sig, ret, functionName, t0, t1, t2, t3, t4, t5, t6, t7, t8, t9, t10) ret functionName(t0 p0, t1 p1, t2 p2, t3 p3, t4 p4, t5 p5, t6 p6, t7 p7, t8 p8, t9 p9, t10 p10) { GL_FUNCTION_TRACE(functionName); if (pthread_getspecific(currentThreadOwnsItsWebGLContext)) emscripten_##functionName(p0, p1, p2, p3, p4, p5, p6, p7, p8, p9, p10); else emscripten_sync_run_in_main_runtime_thread(sig, &emscripten_##functionName, p0, p1, p2, p3, p4, p5, p6, p7, p8, p9, p10); }
 
-#if defined(__EMSCRIPTEN_PTHREADS__) && defined(__EMSCRIPTEN_OFFSCREEN_FRAMEBUFFER__)
-
 #include <pthread.h>
 
 extern pthread_key_t currentActiveWebGLContext;

test/test_other.py

@@ -8685,6 +8685,7 @@ def test_full_js_library_minimal_runtime(self):
     # binaryen tools get run, which can affect how debug info is kept around
     'bigint': [['-sWASM_BIGINT']],
     'pthread': [['-pthread', '-Wno-experimental']],
+    'pthread_offscreen': [['-pthread', '-Wno-experimental', '-sOFFSCREEN_FRAMEBUFFER']],
   })
   def test_closure_full_js_library(self, args):
     # Test for closure errors and warnings in the entire JS library.
@@ -8698,6 +8699,7 @@ def test_closure_full_js_library(self, args):
       '-sFETCH',
       '-sFETCH_SUPPORT_INDEXEDDB',
       '-sLEGACY_GL_EMULATION',
+      '-sMAX_WEBGL_VERSION=2',
     ] + args)
 
   def test_closure_webgpu(self):