Changeset 156376 in webkit for trunk/Source/JavaScriptCore/jit/JITOpcodes.cpp

Timestamp:

Sep 24, 2013, 5:37:57 PM (12 years ago)

Author:

[email protected]

Message:

op_get_callee shouldn't use value profiling
​https://bugs.webkit.org/show_bug.cgi?id=121821

Reviewed by Filip Pizlo.

Source/JavaScriptCore:

Currently it's one of the two opcodes that uses m_singletonValue, which is unnecessary.
Our current plan is to remove m_singletonValue so that GenGC can have a simpler story
for handling CodeBlocks/FunctionExecutables during nursery collections.

Instead of using a ValueProfile op_get_callee now has a simple inline cache of the most
recent JSFunction that we saw.

• bytecode/CodeBlock.cpp:

(JSC::CodeBlock::CodeBlock):
(JSC::CodeBlock::finalizeUnconditionally):

• bytecompiler/BytecodeGenerator.cpp:

(JSC::BytecodeGenerator::emitCreateThis):

• dfg/DFGByteCodeParser.cpp:

(JSC::DFG::ByteCodeParser::parseBlock):

• jit/JIT.cpp:

(JSC::JIT::privateCompileSlowCases):

• jit/JIT.h:
• jit/JITOpcodes.cpp:

(JSC::JIT::emit_op_get_callee):
(JSC::JIT::emitSlow_op_get_callee):

• jit/JITOpcodes32_64.cpp:

(JSC::JIT::emit_op_get_callee):
(JSC::JIT::emitSlow_op_get_callee):

• llint/LowLevelInterpreter32_64.asm:
• llint/LowLevelInterpreter64.asm:
• runtime/CommonSlowPaths.cpp:

(JSC::SLOW_PATH_DECL):

• runtime/CommonSlowPaths.h:

LayoutTests:

Added two tests to make sure we didn't regress the performance of op_get_callee.

• js/regress/get_callee_monomorphic-expected.txt: Added.
• js/regress/get_callee_monomorphic.html: Added.
• js/regress/get_callee_polymorphic-expected.txt: Added.
• js/regress/get_callee_polymorphic.html: Added.
• js/regress/script-tests/get_callee_monomorphic.js: Added.
• js/regress/script-tests/get_callee_polymorphic.js: Added.

File:

• trunk/Source/JavaScriptCore/jit/JITOpcodes.cpp (modified) (1 diff)

trunk/Source/JavaScriptCore/jit/JITOpcodes.cpp

@@ -879 +879 @@
 {
     int result = currentInstruction[1].u.operand;
+    WriteBarrierBase<JSCell>* cachedFunction = &currentInstruction[2].u.jsCell;
     emitGetFromCallFrameHeaderPtr(JSStack::Callee, regT0);
-    emitValueProfilingSite(regT4);
+
+    loadPtr(cachedFunction, regT2);
+    addSlowCase(branchPtr(NotEqual, regT0, regT2));
+
     emitPutVirtualRegister(result);
+}
+
+void JIT::emitSlow_op_get_callee(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+{
+    linkSlowCase(iter);
+
+    JITSlowPathCall slowPathCall(this, currentInstruction, slow_path_get_callee);
+    slowPathCall.call();
+    emitGetVirtualRegister(currentInstruction[1].u.operand, regT0);
 }