Changeset 37831 in webkit for trunk/JavaScriptCore/VM/CodeBlock.cpp

Timestamp:

Oct 23, 2008, 3:29:54 PM (17 years ago)

Author:

[email protected]

Message:

2008-10-23 Gavin Barraclough <​[email protected]>

Reviewed by Oliver Hunt.

Fix hideous pathological case performance when looking up repatch info, bug #21727.

When repatching JIT code to optimize we look up records providing information about
the generated code (also used to track recsources used in linking to be later released).
The lookup was being performed using a linear scan of all such records.

(1) Split up the different types of reptach information. This means we can search them

separately, and in some cases should reduce their size.

(2) In the case of property accesses, search with a binary chop over the data.
(3) In the case of calls, pass a pointer to the repatch info into the relink function.

• VM/CTI.cpp: (JSC::CTI::CTI): (JSC::CTI::compileOpCall): (JSC::CTI::privateCompileMainPass): (JSC::CTI::privateCompileSlowCases): (JSC::CTI::privateCompile): (JSC::CTI::unlinkCall): (JSC::CTI::linkCall):
• VM/CTI.h:
• VM/CodeBlock.cpp: (JSC::CodeBlock::dump): (JSC::CodeBlock::~CodeBlock): (JSC::CodeBlock::unlinkCallers): (JSC::CodeBlock::derefStructureIDs):
• VM/CodeBlock.h: (JSC::StructureStubInfo::StructureStubInfo): (JSC::CallLinkInfo::CallLinkInfo): (JSC::CallLinkInfo::setUnlinked): (JSC::CallLinkInfo::isLinked): (JSC::getStructureStubInfoReturnLocation): (JSC::binaryChop): (JSC::CodeBlock::addCaller): (JSC::CodeBlock::getStubInfo):
• VM/CodeGenerator.cpp: (JSC::CodeGenerator::emitResolve): (JSC::CodeGenerator::emitGetById): (JSC::CodeGenerator::emitPutById): (JSC::CodeGenerator::emitCall): (JSC::CodeGenerator::emitConstruct):
• VM/Machine.cpp: (JSC::Machine::cti_vm_lazyLinkCall):

File:

• trunk/JavaScriptCore/VM/CodeBlock.cpp (modified) (4 diffs)

trunk/JavaScriptCore/VM/CodeBlock.cpp

@@ -276 +276 @@
     }
 
-    if (structureIDInstructions.size()) {
+    if (globalResolveInstructions.size() || propertyAccessInstructions.size())
         printf("\nStructureIDs:\n");
+
+    if (globalResolveInstructions.size()) {
         size_t i = 0;
         do {
-             printStructureIDs(&instructions[structureIDInstructions[i].opcodeIndex]);
+             printStructureIDs(&instructions[globalResolveInstructions[i]]);
              ++i;
-        } while (i < structureIDInstructions.size());
+        } while (i < globalResolveInstructions.size());
+    }
+    if (propertyAccessInstructions.size()) {
+        size_t i = 0;
+        do {
+             printStructureIDs(&instructions[propertyAccessInstructions[i].opcodeIndex]);
+             ++i;
+        } while (i < propertyAccessInstructions.size());
     }
  
@@ -942 +951 @@
 CodeBlock::~CodeBlock()
 {
-    size_t size = structureIDInstructions.size();
-    for (size_t i = 0; i < size; ++i) {
-        derefStructureIDs(&instructions[structureIDInstructions[i].opcodeIndex]);
-        if (structureIDInstructions[i].stubRoutine)
-            WTF::fastFreeExecutable(structureIDInstructions[i].stubRoutine);
-        if (CallLinkInfo* callLinkInfo = structureIDInstructions[i].linkInfoPtr) {
+    for (size_t size = globalResolveInstructions.size(), i = 0; i < size; ++i) {
+        derefStructureIDs(&instructions[globalResolveInstructions[i]]);
+    }
+
+    for (size_t size = propertyAccessInstructions.size(), i = 0; i < size; ++i) {
+        derefStructureIDs(&instructions[propertyAccessInstructions[i].opcodeIndex]);
+        if (propertyAccessInstructions[i].stubRoutine)
+            WTF::fastFreeExecutable(propertyAccessInstructions[i].stubRoutine);
+    }
+
+    for (size_t size = callLinkInfos.size(), i = 0; i < size; ++i) {
+        CallLinkInfo* callLinkInfo = &callLinkInfos[i];
+        if (callLinkInfo->isLinked())
             callLinkInfo->callee->removeCaller(callLinkInfo);
-            delete callLinkInfo;
-        }
     }
 
@@ -967 +981 @@
     for (size_t i = 0; i < size; ++i) {
         CallLinkInfo* currentCaller = linkedCallerList[i];
-        CTI::unlinkCall(currentCaller->callerStructureStubInfo);
-        currentCaller->callerStructureStubInfo->linkInfoPtr = 0;
-        delete currentCaller;
+        CTI::unlinkCall(currentCaller);
+        currentCaller->setUnlinked();
     }
     linkedCallerList.clear();
@@ -1010 +1023 @@
     
     // These instructions don't ref their StructureIDs.
-    ASSERT(vPC[0].u.opcode == machine->getOpcode(op_get_by_id) || vPC[0].u.opcode == machine->getOpcode(op_put_by_id) || vPC[0].u.opcode == machine->getOpcode(op_get_by_id_generic) || vPC[0].u.opcode == machine->getOpcode(op_put_by_id_generic) || vPC[0].u.opcode == machine->getOpcode(op_get_array_length) || vPC[0].u.opcode == machine->getOpcode(op_get_string_length)
-        || vPC[0].u.opcode == machine->getOpcode(op_call_eval) || vPC[0].u.opcode == machine->getOpcode(op_call) || vPC[0].u.opcode == machine->getOpcode(op_construct));
+    ASSERT(vPC[0].u.opcode == machine->getOpcode(op_get_by_id) || vPC[0].u.opcode == machine->getOpcode(op_put_by_id) || vPC[0].u.opcode == machine->getOpcode(op_get_by_id_generic) || vPC[0].u.opcode == machine->getOpcode(op_put_by_id_generic) || vPC[0].u.opcode == machine->getOpcode(op_get_array_length) || vPC[0].u.opcode == machine->getOpcode(op_get_string_length));
 }