Bug 1711926 - Spew WebGPU validation errors to the console r=jimb

Differential Revision: https://phabricator.services.mozilla.com/D115503

dom/webgpu/ipc/WebGPUChild.cpp

@@ -4,7 +4,9 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "WebGPUChild.h"
+#include "js/Warnings.h"  // JS::WarnUTF8
 #include "mozilla/EnumTypeTraits.h"
+#include "mozilla/dom/ScriptSettings.h"
 #include "mozilla/dom/WebGPUBinding.h"
 #include "mozilla/dom/GPUUncapturedErrorEvent.h"
 #include "mozilla/webgpu/ValidationError.h"
@@ -18,6 +20,20 @@ NS_IMPL_CYCLE_COLLECTION(WebGPUChild)
 NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(WebGPUChild, AddRef)
 NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(WebGPUChild, Release)
 
+void WebGPUChild::JsWarning(nsIGlobalObject* aGlobal,
+                            const nsACString& aMessage) {
+  const auto& flatString = PromiseFlatCString(aMessage);
+  if (aGlobal) {
+    dom::AutoJSAPI api;
+    if (api.Init(aGlobal)) {
+      JS::WarnUTF8(api.cx(), "%s", flatString.get());
+    }
+  } else {
+    printf_stderr("Validation error without device target: %s\n",
+                  flatString.get());
+  }
+}
+
 static ffi::WGPUCompareFunction ConvertCompareFunction(
     const dom::GPUCompareFunction& aCompare) {
   // Value of 0 = Undefined is reserved on the C side for "null" semantics.
@@ -790,16 +806,14 @@ RawId WebGPUChild::DeviceCreateRenderPipeline(
 
 ipc::IPCResult WebGPUChild::RecvError(RawId aDeviceId,
                                       const nsACString& aMessage) {
-  if (!aDeviceId) {
-    // TODO: figure out how to report these kinds of errors
-    printf_stderr("Validation error without device target: %s\n",
-                  PromiseFlatCString(aMessage).get());
-  } else if (mDeviceMap.find(aDeviceId) == mDeviceMap.end()) {
-    printf_stderr("Validation error on a dropped device: %s\n",
-                  PromiseFlatCString(aMessage).get());
+  auto targetIter = mDeviceMap.find(aDeviceId);
+  if (!aDeviceId || targetIter == mDeviceMap.end()) {
+    JsWarning(nullptr, aMessage);
   } else {
-    auto* target = mDeviceMap[aDeviceId];
+    auto* target = targetIter->second;
     MOZ_ASSERT(target);
+    JsWarning(target->GetOwnerGlobal(), aMessage);
+
     dom::GPUUncapturedErrorEventInit init;
     init.mError.SetAsGPUValidationError() =
         new ValidationError(target, aMessage);

dom/webgpu/ipc/WebGPUChild.h

@@ -84,6 +84,8 @@ class WebGPUChild final : public PWebGPUChild, public SupportsWeakPtr {
  private:
   virtual ~WebGPUChild();
 
+  void JsWarning(nsIGlobalObject* aGlobal, const nsACString& aMessage);
+
   // AddIPDLReference and ReleaseIPDLReference are only to be called by
   // CompositorBridgeChild's AllocPWebGPUChild and DeallocPWebGPUChild methods
   // respectively. We intentionally make them private to prevent misuse.