Changeset 276858 in webkit

Timestamp:

Apr 30, 2021 3:48:43 PM (3 years ago)

Author:

fpizlo@apple.com

Message:

Make small JIT pool tests pass on AS
​https://bugs.webkit.org/show_bug.cgi?id=225256

Reviewed by Mark Lam.

If we ask for a JIT pool that is smaller than the smallest possible "region" (thing with jump
island) that we can create -- i.e. smaller than a jump region, then assume that the user is
asking us to create a pool that has that much usable space plus a jump region.

I think that this makes the option easier to use when you're testing ridiculously small JIT
pools, which we happen to do in our test suite.

Also remove some dead options I didn't mean to commit.

• jit/ExecutableAllocator.cpp:

(JSC::initializeJITPageReservation):

• runtime/OptionsList.h:

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• jit/ExecutableAllocator.cpp (modified) (1 diff)
• runtime/OptionsList.h (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2021-04-30  Filip Pizlo  <fpizlo@apple.com>
+
+        Make small JIT pool tests pass on AS
+        https://bugs.webkit.org/show_bug.cgi?id=225256
+
+        Reviewed by Mark Lam.
+
+        If we ask for a JIT pool that is smaller than the smallest possible "region" (thing with jump
+        island) that we can create -- i.e. smaller than a jump region, then assume that the user is
+        asking us to create a pool that has that much usable space plus a jump region.
+
+        I think that this makes the option easier to use when you're testing ridiculously small JIT
+        pools, which we happen to do in our test suite.
+
+        Also remove some dead options I didn't mean to commit.
+
+        * jit/ExecutableAllocator.cpp:
+        (JSC::initializeJITPageReservation):
+        * runtime/OptionsList.h:
+
 2021-04-30  Filip Pizlo  <fpizlo@apple.com>
 

trunk/Source/JavaScriptCore/jit/ExecutableAllocator.cpp

@@ -333 +333 @@
     reservation.size = fixedExecutableMemoryPoolSize;
 
-    if (Options::jitMemoryReservationSize())
+    if (Options::jitMemoryReservationSize()) {
         reservation.size = Options::jitMemoryReservationSize();
 
+#if ENABLE(JUMP_ISLANDS)
+        // If asked for a reservation smaller than island size, assume that we want that size allocation
+        // plus an island. The alternative would be to turn off jump islands, but since we only use
+        // this for testing, this is probably the easier way to do it.
+        //
+        // The main reason for this is that some JSC stress tests run with a 50KB pool. This hack means
+        // we don't have to change anything about those tests.
+        if (reservation.size < islandRegionSize)
+            reservation.size += islandRegionSize;
+#endif // ENABLE(JUMP_ISLANDS)
+    }
     reservation.size = std::max(roundUpToMultipleOf(pageSize(), reservation.size), pageSize() * 2);
 

trunk/Source/JavaScriptCore/runtime/OptionsList.h

@@ -533 +533 @@
     v(Bool, useSharedArrayBuffer, false, Normal, nullptr) \
     v(Bool, useTopLevelAwait, true, Normal, "allow the await keyword at the top level of a module.") \
-    v(Bool, dumpLinking, false, Normal, nullptr) \
-    v(Bool, verifySame4GBLink, false, Normal, nullptr) \
     v(Bool, verboseExecutablePoolAllocation, false, Normal, nullptr) \