Changeset 64938 in webkit for trunk/JavaScriptCore/assembler/X86Assembler.h

Timestamp:

Aug 7, 2010, 11:04:59 PM (15 years ago)

Author:

[email protected]

Message:

2010-08-07 Nathan Lawrence <​[email protected]>

Reviewed by Geoffrey Garen.

The JIT code contains a number of direct references to GC'd objects.
When we have movable objects, these references will need to be
updated.

• Android.mk:
• CMakeLists.txt:
• GNUmakefile.am:
• JavaScriptCore.gypi:
• JavaScriptCore.pro:
• JavaScriptCore.xcodeproj/project.pbxproj:
• assembler/AbstractMacroAssembler.h: (JSC::AbstractMacroAssembler::int32AtLocation): (JSC::AbstractMacroAssembler::pointerAtLocation): (JSC::AbstractMacroAssembler::jumpTarget):
• assembler/MacroAssembler.h: (JSC::MacroAssembler::loadPtrWithPatch):

Normally, loadPtr will optimize when the register is eax. Since
the slightly smaller instruction changes the offsets, it messes up
our ability to repatch the code. We added this new instruction
that garuntees a constant size.

• assembler/MacroAssemblerX86.h: (JSC::MacroAssemblerX86::load32WithPatch):

Changed load32 in the same way described above.

(JSC::MacroAssemblerX86::load32):

Moved the logic to optimize laod32 from movl_mr to load32

(JSC::MacroAssemblerX86::store32):

Moved the logic to optimize store32 from movl_rm to store32

• assembler/X86Assembler.h: (JSC::X86Assembler::movl_rm): (JSC::X86Assembler::movl_mr): (JSC::X86Assembler::int32AtLocation): (JSC::X86Assembler::pointerAtLocation): (JSC::X86Assembler::jumpTarget):
• bytecode/CodeBlock.cpp: (JSC::CodeBlock::markAggregate):
• bytecode/Instruction.h:

As described in StructureStubInfo.h, we needed to add additional
fields to both StructureStubInfo and
PolymorphicAccessStructureList so that we can determine the
structure of the JITed code at patch time.

(JSC::PolymorphicAccessStructureList::PolymorphicStubInfo::set):
(JSC::PolymorphicAccessStructureList::PolymorphicAccessStructureList):

• bytecode/StructureStubInfo.cpp: (JSC::StructureStubInfo::markAggregate):

Added this function to mark the JITed code that correosponds to
this structure stub info.

• bytecode/StructureStubInfo.h: (JSC::StructureStubInfo::initGetByIdProto): (JSC::StructureStubInfo::initGetByIdChain): (JSC::StructureStubInfo::):
• jit/JIT.h:
• jit/JITMarkObjects.cpp: Added. (JSC::JIT::patchPrototypeStructureAddress): (JSC::JIT::patchGetDirectOffset): (JSC::JIT::markGetByIdProto): (JSC::JIT::markGetByIdChain): (JSC::JIT::markGetByIdProtoList): (JSC::JIT::markPutByIdTransition): (JSC::JIT::markGlobalObjectReference):
• jit/JITPropertyAccess.cpp:

Added asserts for the patch offsets.

(JSC::JIT::compileGetDirectOffset):
(JSC::JIT::testPrototype):
(JSC::JIT::privateCompilePutByIdTransition):
(JSC::JIT::privateCompileGetByIdProto):
(JSC::JIT::privateCompileGetByIdProtoList):
(JSC::JIT::privateCompileGetByIdChainList):
(JSC::JIT::privateCompileGetByIdChain):

• jit/JITPropertyAccess32_64.cpp: (JSC::JIT::compileGetDirectOffset): (JSC::JIT::testPrototype): (JSC::JIT::privateCompilePutByIdTransition): (JSC::JIT::privateCompileGetByIdProto): (JSC::JIT::privateCompileGetByIdProtoList): (JSC::JIT::privateCompileGetByIdChainList): (JSC::JIT::privateCompileGetByIdChain):
• jit/JITStubs.cpp: (JSC::setupPolymorphicProtoList):
• wtf/Platform.h:

Added ENABLE_MOVABLE_GC_OBJECTS flag

File:

• trunk/JavaScriptCore/assembler/X86Assembler.h (modified) (2 diffs)

trunk/JavaScriptCore/assembler/X86Assembler.h

@@ -1155 +1155 @@
     void movl_rm(RegisterID src, void* addr)
     {
-        if (src == X86Registers::eax)
-            movl_EAXm(addr);
-        else 
-            m_formatter.oneByteOp(OP_MOV_EvGv, src, addr);
+        m_formatter.oneByteOp(OP_MOV_EvGv, src, addr);
     }
     
     void movl_mr(void* addr, RegisterID dst)
     {
-        if (dst == X86Registers::eax)
-            movl_mEAX(addr);
-        else
-            m_formatter.oneByteOp(OP_MOV_GvEv, dst, addr);
+        m_formatter.oneByteOp(OP_MOV_GvEv, dst, addr);
     }
 
@@ -1558 +1552 @@
 
         setPointer(reinterpret_cast<char*>(code) + where.m_offset, value);
+    }
+
+    static int32_t int32AtLocation(void* where)
+    {
+        return static_cast<int32_t*>(where)[-1];
+    }
+
+    static void* pointerAtLocation(void* where)
+    {
+        return static_cast<void**>(where)[-1];
+    }
+
+    static void* jumpTarget(void* jump)
+    {
+        intptr_t src = reinterpret_cast<intptr_t>(jump);
+        int32_t offset = static_cast<int32_t*>(jump)[-1];
+        return reinterpret_cast<void*>(src + offset);
     }