Changeset 185160 in webkit for trunk/Source/JavaScriptCore/bytecode/GetByIdStatus.cpp

Timestamp:

Jun 3, 2015, 1:04:00 PM (10 years ago)

Author:

[email protected]

Message:

GetById and PutById profiling should be more precise about it takes slow path
​https://bugs.webkit.org/show_bug.cgi?id=145590

Reviewed by Geoffrey Garen.

Source/JavaScriptCore:

If a ById access ever takes slow path, we want the DFG and FTL to know this. Previously we
were relying on slow path counts, which conflate slow paths taken due to a megamorphic
access and slow paths taken due to IC building.

• bytecode/GetByIdStatus.cpp:

(JSC::GetByIdStatus::computeFor):
(JSC::GetByIdStatus::computeForStubInfo):

• bytecode/PutByIdStatus.cpp:

(JSC::PutByIdStatus::computeFor):
(JSC::PutByIdStatus::computeForStubInfo):

• bytecode/StructureStubInfo.h:

(JSC::StructureStubInfo::StructureStubInfo):

• ftl/FTLIntrinsicRepository.h:
• ftl/FTLLowerDFGToLLVM.cpp:

(JSC::FTL::LowerDFGToLLVM::compileGetById):

• jit/JITOperations.cpp:
• jit/JITOperations.h:

LayoutTests:

Added just two more tests for getters and setters. I needed more microbenchmarks to track
down a regression in an earlier version of this patch.

• js/regress/getter-prototype-expected.txt: Added.
• js/regress/getter-prototype.html: Added.
• js/regress/script-tests/getter-prototype.js: Added.
• js/regress/script-tests/setter-prototype.js: Added.
• js/regress/setter-prototype-expected.txt: Added.
• js/regress/setter-prototype.html: Added.

File:

• trunk/Source/JavaScriptCore/bytecode/GetByIdStatus.cpp (modified) (3 diffs)

trunk/Source/JavaScriptCore/bytecode/GetByIdStatus.cpp

@@ -104 +104 @@
     
     if (!result.takesSlowPath()
-        && (hasExitSite(locker, profiledBlock, bytecodeIndex)
-            || profiledBlock->likelyToTakeSlowCase(bytecodeIndex)))
+        && hasExitSite(locker, profiledBlock, bytecodeIndex))
         return GetByIdStatus(result.makesCalls() ? MakesCalls : TakesSlowPath, true);
 #else
@@ -122 +121 @@
     CallLinkStatus::ExitSiteData callExitSiteData)
 {
-    if (!stubInfo || !stubInfo->seen)
+    if (!stubInfo)
+        return GetByIdStatus(NoInformation);
+    
+    if (!stubInfo->seen)
         return GetByIdStatus(NoInformation);
     
@@ -135 +137 @@
         }
     }
+    
+    if (stubInfo->tookSlowPath)
+        return GetByIdStatus(slowPathState);
     
     // Finally figure out if we can derive an access strategy.