Changeset 129045 in webkit for trunk/Source/JavaScriptCore/dfg/DFGArrayMode.cpp

Timestamp:

Sep 19, 2012, 2:43:10 PM (13 years ago)

Author:

[email protected]

Message:

DFG should not emit PutByVal hole case unless it has to
​https://bugs.webkit.org/show_bug.cgi?id=97080

Reviewed by Geoffrey Garen.

This causes us to generate less code for typical PutByVal's. But if profiling tells us
that the hole case is being hit, we generate the same code as we would have generated
before. This seems like a slight speed-up across the board.

• assembler/MacroAssemblerARMv7.h:

(JSC::MacroAssemblerARMv7::store8):
(MacroAssemblerARMv7):

• assembler/MacroAssemblerX86.h:

(MacroAssemblerX86):
(JSC::MacroAssemblerX86::store8):

• assembler/MacroAssemblerX86_64.h:

(MacroAssemblerX86_64):
(JSC::MacroAssemblerX86_64::store8):

• assembler/X86Assembler.h:

(X86Assembler):
(JSC::X86Assembler::movb_i8m):

• bytecode/ArrayProfile.h:

(JSC::ArrayProfile::ArrayProfile):
(JSC::ArrayProfile::addressOfMayStoreToHole):
(JSC::ArrayProfile::mayStoreToHole):
(ArrayProfile):

• dfg/DFGArrayMode.cpp:

(JSC::DFG::fromObserved):
(JSC::DFG::modeAlreadyChecked):
(JSC::DFG::modeToString):

• dfg/DFGArrayMode.h:

(DFG):
(JSC::DFG::mayStoreToHole):

• dfg/DFGSpeculativeJIT32_64.cpp:

(JSC::DFG::SpeculativeJIT::compile):

• dfg/DFGSpeculativeJIT64.cpp:

(JSC::DFG::SpeculativeJIT::compile):

• jit/JIT.h:

(JIT):

• jit/JITInlineMethods.h:

(JSC::JIT::emitArrayProfileStoreToHoleSpecialCase):
(JSC):

• jit/JITPropertyAccess.cpp:

(JSC::JIT::emit_op_put_by_val):

• jit/JITPropertyAccess32_64.cpp:

(JSC::JIT::emit_op_put_by_val):

• llint/LowLevelInterpreter32_64.asm:
• llint/LowLevelInterpreter64.asm:

File:

• trunk/Source/JavaScriptCore/dfg/DFGArrayMode.cpp (modified) (6 diffs)

trunk/Source/JavaScriptCore/dfg/DFGArrayMode.cpp

@@ -43 +43 @@
         return Array::Undecided;
     case asArrayModes(NonArrayWithArrayStorage):
-        return makeSafe ? Array::ArrayStorageOutOfBounds : Array::ArrayStorage;
+        return makeSafe ? Array::ArrayStorageOutOfBounds : (profile->mayStoreToHole() ? Array::ArrayStorageToHole : Array::ArrayStorage);
     case asArrayModes(NonArrayWithSlowPutArrayStorage):
     case asArrayModes(NonArrayWithArrayStorage) | asArrayModes(NonArrayWithSlowPutArrayStorage):
         return Array::SlowPutArrayStorage;
     case asArrayModes(ArrayWithArrayStorage):
-        return makeSafe ? Array::ArrayWithArrayStorageOutOfBounds : Array::ArrayWithArrayStorage;
+        return makeSafe ? Array::ArrayWithArrayStorageOutOfBounds : (profile->mayStoreToHole() ? Array::ArrayWithArrayStorageToHole : Array::ArrayWithArrayStorage);
     case asArrayModes(ArrayWithSlowPutArrayStorage):
     case asArrayModes(ArrayWithArrayStorage) | asArrayModes(ArrayWithSlowPutArrayStorage):
         return Array::ArrayWithSlowPutArrayStorage;
     case asArrayModes(NonArrayWithArrayStorage) | asArrayModes(ArrayWithArrayStorage):
-        return makeSafe ? Array::PossiblyArrayWithArrayStorageOutOfBounds : Array::PossiblyArrayWithArrayStorage;
+        return makeSafe ? Array::PossiblyArrayWithArrayStorageOutOfBounds : (profile->mayStoreToHole() ? Array::PossiblyArrayWithArrayStorageToHole : Array::PossiblyArrayWithArrayStorage);
     case asArrayModes(NonArrayWithSlowPutArrayStorage) | asArrayModes(ArrayWithSlowPutArrayStorage):
     case asArrayModes(NonArrayWithArrayStorage) | asArrayModes(ArrayWithArrayStorage) | asArrayModes(NonArrayWithSlowPutArrayStorage) | asArrayModes(ArrayWithSlowPutArrayStorage):
@@ -140 +140 @@
         
     case Array::ArrayStorage:
+    case Array::ArrayStorageToHole:
     case Array::ArrayStorageOutOfBounds:
     case Array::PossiblyArrayWithArrayStorage:
+    case Array::PossiblyArrayWithArrayStorageToHole:
     case Array::PossiblyArrayWithArrayStorageOutOfBounds:
         return value.m_currentKnownStructure.hasSingleton()
@@ -152 +154 @@
         
     case Array::ArrayWithArrayStorage:
+    case Array::ArrayWithArrayStorageToHole:
     case Array::ArrayWithArrayStorageOutOfBounds:
         return value.m_currentKnownStructure.hasSingleton()
@@ -216 +219 @@
     case Array::ArrayStorage:
         return "ArrayStorage";
+    case Array::ArrayStorageToHole:
+        return "ArrayStorageToHole";
     case Array::SlowPutArrayStorage:
         return "SlowPutArrayStorage";
@@ -222 +227 @@
     case Array::ArrayWithArrayStorage:
         return "ArrayWithArrayStorage";
+    case Array::ArrayWithArrayStorageToHole:
+        return "ArrayWithArrayStorageToHole";
     case Array::ArrayWithSlowPutArrayStorage:
         return "ArrayWithSlowPutArrayStorage";
@@ -228 +235 @@
     case Array::PossiblyArrayWithArrayStorage:
         return "PossiblyArrayWithArrayStorage";
+    case Array::PossiblyArrayWithArrayStorageToHole:
+        return "PossiblyArrayWithArrayStorageToHole";
     case Array::PossiblyArrayWithSlowPutArrayStorage:
         return "PossiblyArrayWithSlowPutArrayStorage";