Bug 1465470 Part 5 - Avoid recording time events at non-deterministic points in the JS engine, r=jonco.

--HG--
extra : rebase_source : ed238c0ad5861a3149f695a5e46d221cf22cb27d

js/src/frontend/BytecodeCompiler.cpp

@@ -799,7 +799,7 @@ frontend::CompileLazyFunction(JSContext* cx, Handle<LazyScript*> lazy, const cha
     // syntax parsing and start of full parsing, so we do this now rather than
     // after parsing below.
     if (!lazy->scriptSource()->parseEnded().IsNull()) {
-        const mozilla::TimeDuration delta = mozilla::TimeStamp::Now() -
+        const mozilla::TimeDuration delta = ReallyNow() -
             lazy->scriptSource()->parseEnded();
 
         // Differentiate between web-facing and privileged code, to aid

js/src/gc/GC.cpp

@@ -954,7 +954,7 @@ GCRuntime::GCRuntime(JSRuntime* rt) :
     numArenasFreeCommitted(0),
     verifyPreData(nullptr),
     chunkAllocationSinceLastGC(false),
-    lastGCTime(mozilla::TimeStamp::Now()),
+    lastGCTime(ReallyNow()),
     mode(TuningDefaults::Mode),
     numActiveZoneIters(0),
     cleanUpEverything(false),
@@ -3247,7 +3247,7 @@ SliceBudget::SliceBudget(TimeBudget time)
         makeUnlimited();
     } else {
         // Note: TimeBudget(0) is equivalent to WorkBudget(CounterReset).
-        deadline = mozilla::TimeStamp::Now() + mozilla::TimeDuration::FromMilliseconds(time.budget);
+        deadline = ReallyNow() + mozilla::TimeDuration::FromMilliseconds(time.budget);
         counter = CounterReset;
     }
 }
@@ -3280,7 +3280,7 @@ SliceBudget::checkOverBudget()
     if (deadline.IsNull())
         return true;
 
-    bool over = mozilla::TimeStamp::Now() >= deadline;
+    bool over = ReallyNow() >= deadline;
     if (!over)
         counter = CounterReset;
     return over;
@@ -4238,7 +4238,7 @@ GCRuntime::prepareZonesForCollection(JS::gcreason::Reason reason, bool* isFullOu
     *isFullOut = true;
     bool any = false;
 
-    auto currentTime = mozilla::TimeStamp::Now();
+    auto currentTime = ReallyNow();
 
     for (ZonesIter zone(rt, WithAtoms); !zone.done(); zone.next()) {
         /* Set up which zones will be collected. */

js/src/gc/Nursery.cpp

@@ -375,13 +375,13 @@ js::Nursery::allocate(size_t size)
         if (chunkno == maxChunkCount())
             return nullptr;
         if (MOZ_UNLIKELY(chunkno == allocatedChunkCount())) {
-            mozilla::TimeStamp start = TimeStamp::Now();
+            mozilla::TimeStamp start = ReallyNow();
             {
                 AutoLockGCBgAlloc lock(runtime());
                 if (!allocateNextChunk(chunkno, lock))
                     return nullptr;
             }
-            timeInChunkAlloc_ += TimeStamp::Now() - start;
+            timeInChunkAlloc_ += ReallyNow() - start;
             MOZ_ASSERT(chunkno < allocatedChunkCount());
         }
         setCurrentChunk(chunkno);

js/src/vm/HelperThreads.cpp

@@ -1547,7 +1547,7 @@ static inline
 TimeDuration
 TimeSince(TimeStamp prev)
 {
-    TimeStamp now = TimeStamp::Now();
+    TimeStamp now = ReallyNow();
     // Sadly this happens sometimes.
     MOZ_ASSERT(now >= prev);
     if (now < prev)

js/src/vm/JSScript.h

@@ -29,6 +29,7 @@
 #include "vm/Scope.h"
 #include "vm/Shape.h"
 #include "vm/SharedImmutableStringsCache.h"
+#include "vm/Time.h"
 
 namespace JS {
 struct ScriptSourceInfo;
@@ -682,7 +683,7 @@ class ScriptSource
     // Inform `this` source that it has been fully parsed.
     void recordParseEnded() {
         MOZ_ASSERT(parseEnded_.IsNull());
-        parseEnded_ = mozilla::TimeStamp::Now();
+        parseEnded_ = ReallyNow();
     }
 };
 

js/src/vm/Time.h

@@ -7,6 +7,9 @@
 #ifndef vm_Time_h
 #define vm_Time_h
 
+#include "mozilla/RecordReplay.h"
+#include "mozilla/TimeStamp.h"
+
 #include <stddef.h>
 #include <stdint.h>
 
@@ -167,4 +170,16 @@ ReadTimestampCounter(void)
 
 #endif
 
+namespace js {
+
+// Get the current time, bypassing any record/replay instrumentation.
+static inline mozilla::TimeStamp
+ReallyNow()
+{
+    mozilla::recordreplay::AutoPassThroughThreadEvents pt;
+    return mozilla::TimeStamp::Now();
+}
+
+} // namespace js
+
 #endif /* vm_Time_h */