commit 9d38131e7dde41cd6d4d432ed45a2bd763485e70
parent 122bc2e9ef7375f608e003ad841578f7dfe30654
Author: Tooru Fujisawa <arai_a@mac.com>
Date: Tue, 11 Nov 2025 08:26:19 +0000
Bug 1997870 - Part 3: Split EncodeBytecodeAndSave into two steps. r=bthrall
Differential Revision: https://phabricator.services.mozilla.com/D271034
Diffstat:
3 files changed, 80 insertions(+), 35 deletions(-)
diff --git a/dom/script/ScriptLoader.cpp b/dom/script/ScriptLoader.cpp
@@ -3641,10 +3641,27 @@ void ScriptLoader::UpdateDiskCache() {
continue;
}
- EncodeBytecodeAndSave(fc, loadedScript);
+ MOZ_ASSERT(loadedScript->HasStencil());
+
+ Vector<uint8_t> compressed;
+ if (!EncodeAndCompress(fc, loadedScript, loadedScript->GetStencil(),
+ loadedScript->SRIAndBytecode(), compressed)) {
+ loadedScript->DropDiskCacheReference();
+ loadedScript->DropBytecode();
+ TRACE_FOR_TEST(loadedScript, "diskcache:failed");
+ continue;
+ }
+
+ if (!SaveToDiskCache(loadedScript, compressed)) {
+ loadedScript->DropDiskCacheReference();
+ loadedScript->DropBytecode();
+ TRACE_FOR_TEST(loadedScript, "diskcache:failed");
+ continue;
+ }
loadedScript->DropDiskCacheReference();
loadedScript->DropBytecode();
+ TRACE_FOR_TEST(loadedScript, "diskcache:saved");
}
mDiskCacheQueue.Clear();
@@ -3652,25 +3669,20 @@ void ScriptLoader::UpdateDiskCache() {
}
/* static */
-void ScriptLoader::EncodeBytecodeAndSave(
- JS::FrontendContext* aFc, JS::loader::LoadedScript* aLoadedScript) {
- MOZ_ASSERT(aLoadedScript->HasDiskCacheReference());
- MOZ_ASSERT(aLoadedScript->HasStencil());
-
- auto bytecodeFailed = mozilla::MakeScopeExit(
- [&]() { TRACE_FOR_TEST(aLoadedScript, "diskcache:failed"); });
-
- size_t SRILength = aLoadedScript->SRIAndBytecode().length();
+bool ScriptLoader::EncodeAndCompress(
+ JS::FrontendContext* aFc, const JS::loader::LoadedScript* aLoadedScript,
+ JS::Stencil* aStencil, const JS::TranscodeBuffer& aSRI,
+ Vector<uint8_t>& aCompressed) {
+ size_t SRILength = aSRI.length();
MOZ_ASSERT(JS::IsTranscodingBytecodeOffsetAligned(SRILength));
JS::TranscodeBuffer SRIAndBytecode;
- if (!SRIAndBytecode.appendAll(aLoadedScript->SRIAndBytecode())) {
+ if (!SRIAndBytecode.appendAll(aSRI)) {
LOG(("LoadedScript (%p): Cannot allocate buffer", aLoadedScript));
- return;
+ return false;
}
- JS::TranscodeResult result =
- JS::EncodeStencil(aFc, aLoadedScript->GetStencil(), SRIAndBytecode);
+ JS::TranscodeResult result = JS::EncodeStencil(aFc, aStencil, SRIAndBytecode);
if (result != JS::TranscodeResult::Ok) {
// Encoding can be aborted for non-supported syntax (e.g. asm.js), or
@@ -3679,37 +3691,44 @@ void ScriptLoader::EncodeBytecodeAndSave(
JS::ClearFrontendErrors(aFc);
LOG(("LoadedScript (%p): Cannot serialize bytecode", aLoadedScript));
- return;
+ return false;
}
- Vector<uint8_t> compressedBytecode;
// TODO probably need to move this to a helper thread
- if (!ScriptBytecodeCompress(SRIAndBytecode, SRILength, compressedBytecode)) {
- return;
+ if (!ScriptBytecodeCompress(SRIAndBytecode, SRILength, aCompressed)) {
+ return false;
}
- if (compressedBytecode.length() >= UINT32_MAX) {
+ if (aCompressed.length() >= UINT32_MAX) {
LOG(
("LoadedScript (%p): Bytecode cache is too large to be decoded "
"correctly.",
aLoadedScript));
- return;
+ return false;
}
+ return true;
+}
+
+/* static */
+bool ScriptLoader::SaveToDiskCache(
+ const JS::loader::LoadedScript* aLoadedScript,
+ const Vector<uint8_t>& aCompressed) {
+ MOZ_ASSERT(NS_IsMainThread());
+
// Open the output stream to the cache entry alternate data storage. This
// might fail if the stream is already open by another request, in which
// case, we just ignore the current one.
nsCOMPtr<nsIAsyncOutputStream> output;
nsresult rv = aLoadedScript->mCacheInfo->OpenAlternativeOutputStream(
BytecodeMimeTypeFor(aLoadedScript),
- static_cast<int64_t>(compressedBytecode.length()),
- getter_AddRefs(output));
+ static_cast<int64_t>(aCompressed.length()), getter_AddRefs(output));
if (NS_FAILED(rv)) {
LOG(
("LoadedScript (%p): Cannot open bytecode cache (rv = %X, output "
"= %p)",
aLoadedScript, unsigned(rv), output.get()));
- return;
+ return false;
}
MOZ_ASSERT(output);
@@ -3719,20 +3738,18 @@ void ScriptLoader::EncodeBytecodeAndSave(
});
uint32_t n;
- rv = output->Write(reinterpret_cast<char*>(compressedBytecode.begin()),
- compressedBytecode.length(), &n);
+ rv = output->Write(reinterpret_cast<const char*>(aCompressed.begin()),
+ aCompressed.length(), &n);
LOG(
("LoadedScript (%p): Write bytecode cache (rv = %X, length = %u, "
"written = %u)",
- aLoadedScript, unsigned(rv), unsigned(compressedBytecode.length()), n));
+ aLoadedScript, unsigned(rv), unsigned(aCompressed.length()), n));
if (NS_FAILED(rv)) {
- return;
+ return false;
}
- MOZ_RELEASE_ASSERT(compressedBytecode.length() == n);
-
- bytecodeFailed.release();
- TRACE_FOR_TEST(aLoadedScript, "diskcache:saved");
+ MOZ_RELEASE_ASSERT(aCompressed.length() == n);
+ return true;
}
void ScriptLoader::GiveUpDiskCaching() {
diff --git a/dom/script/ScriptLoader.h b/dom/script/ScriptLoader.h
@@ -757,10 +757,21 @@ class ScriptLoader final : public JS::loader::ScriptLoaderInterface {
public:
/**
- * Encode the stencils and save the bytecode to the necko cache.
+ * Encode the stencils and compress it.
+ * aLoadedScript is used only for logging purpose, in order to allow
+ * performing this off main thread.
*/
- static void EncodeBytecodeAndSave(JS::FrontendContext* aFc,
- JS::loader::LoadedScript* aLoadedScript);
+ static bool EncodeAndCompress(JS::FrontendContext* aFc,
+ const JS::loader::LoadedScript* aLoadedScript,
+ JS::Stencil* aStencil,
+ const JS::TranscodeBuffer& aSRI,
+ Vector<uint8_t>& aCompressed);
+
+ /**
+ * Save the bytecode to the necko cache.
+ */
+ static bool SaveToDiskCache(const JS::loader::LoadedScript* aLoadedScript,
+ const Vector<uint8_t>& aCompressed);
private:
/**
diff --git a/dom/script/SharedScriptCache.cpp b/dom/script/SharedScriptCache.cpp
@@ -8,6 +8,7 @@
#include "ScriptLoadHandler.h" // ScriptLoadHandler
#include "ScriptLoader.h" // ScriptLoader
+#include "ScriptTrace.h" // TRACE_FOR_TEST
#include "js/experimental/CompileScript.h" // JS::FrontendContext, JS::NewFrontendContext, JS::DestroyFrontendContext
#include "mozilla/Maybe.h" // Maybe, Some, Nothing
#include "mozilla/dom/ContentParent.h" // dom::ContentParent
@@ -244,10 +245,26 @@ void SharedScriptCache::UpdateDiskCache() {
}
}
- ScriptLoader::EncodeBytecodeAndSave(fc, loadedScript);
+ Vector<uint8_t> compressed;
+ if (!ScriptLoader::EncodeAndCompress(
+ fc, loadedScript, loadedScript->GetStencil(),
+ loadedScript->SRIAndBytecode(), compressed)) {
+ loadedScript->DropDiskCacheReference();
+ loadedScript->DropBytecode();
+ TRACE_FOR_TEST(loadedScript, "diskcache:failed");
+ continue;
+ }
+
+ if (!ScriptLoader::SaveToDiskCache(loadedScript, compressed)) {
+ loadedScript->DropDiskCacheReference();
+ loadedScript->DropBytecode();
+ TRACE_FOR_TEST(loadedScript, "diskcache:failed");
+ continue;
+ }
loadedScript->DropDiskCacheReference();
loadedScript->DropBytecode();
+ TRACE_FOR_TEST(loadedScript, "diskcache:saved");
}
if (fc) {
