Changeset 60075 in webkit for trunk/JavaScriptCore/bytecode

Timestamp:

May 24, 2010, 11:46:49 AM (15 years ago)

Author:

[email protected]

Message:

​https://bugs.webkit.org/show_bug.cgi?id=39583
Move creation of 'this' object from caller to callee in construction.

Reviewed by Sam Weinig.

Presently the caller of a constructor is responsible for providing a this
object. Instead, move the object creation into a new op_create_this opcode,
planted in the head of the contructor bytecode for a function. Since the
prototype for the object is provided by performing a get_by_id on the callee,
also add a new get_callee opcode (this is used to get the callee JSFunction
into a register so that a normal get_by_id can be used).

Currently the caller is also responsible for detecting when op_construct is
performed on a JSFunction representing a host function, in which case an
exception is thrown – and this check currently takes place when constructing
the this object. Instead, mirroring the recent changes for non-host functions,
add a parallel code-path for native constructors to follow, with a thunk for
invoking native constructors provided by JITStubs, and a constructor-specific
NativeFunction on NativeExecutable. Provide an implementation of a host
constructor which will throw an exception.

• bytecode/CodeBlock.cpp:

(JSC::CodeBlock::dump):
(JSC::CodeBlock::getByIdExceptionInfoForBytecodeOffset):

• bytecode/CodeBlock.h:
• bytecode/Opcode.h:
• bytecompiler/BytecodeGenerator.cpp:

(JSC::BytecodeGenerator::BytecodeGenerator):
(JSC::BytecodeGenerator::emitConstruct):

• bytecompiler/BytecodeGenerator.h:

(JSC::BytecodeGenerator::emitGetByIdExceptionInfo):

• interpreter/Interpreter.cpp:

(JSC::Interpreter::privateExecute):

• jit/JIT.cpp:

(JSC::JIT::privateCompileMainPass):

• jit/JIT.h:
• jit/JITCall.cpp:

(JSC::JIT::compileOpCall):
(JSC::JIT::compileOpCallSlowCase):

• jit/JITCall32_64.cpp:

(JSC::JIT::compileOpCall):
(JSC::JIT::compileOpCallSlowCase):

• jit/JITOpcodes.cpp:

(JSC::JIT::privateCompileCTIMachineTrampolines):
(JSC::JIT::privateCompileCTINativeCall):
(JSC::JIT::emit_op_neq_null):
(JSC::JIT::emit_op_convert_this):
(JSC::JIT::emit_op_get_callee):
(JSC::JIT::emit_op_create_this):

• jit/JITOpcodes32_64.cpp:

(JSC::JIT::privateCompileCTIMachineTrampolines):
(JSC::JIT::privateCompileCTINativeCall):
(JSC::JIT::emit_op_get_callee):
(JSC::JIT::emit_op_create_this):

• jit/JITStubs.cpp:

(JSC::DEFINE_STUB_FUNCTION):
(JSC::JITThunks::hostFunctionStub):

• jit/JITStubs.h:

(JSC::JITThunks::ctiNativeConstruct):
(JSC::):

• runtime/ExceptionHelpers.cpp:

(JSC::createNotAnObjectError):

• runtime/Executable.h:

(JSC::NativeExecutable::create):
(JSC::NativeExecutable::NativeExecutable):

• runtime/JSFunction.cpp:

(JSC::callHostFunctionAsConstructor):

• runtime/JSFunction.h:

Location:

trunk/JavaScriptCore/bytecode

Files:

• CodeBlock.cpp (modified) (3 diffs)
• CodeBlock.h (modified) (1 diff)
• Opcode.h (modified) (2 diffs)

trunk/JavaScriptCore/bytecode/CodeBlock.cpp

@@ -500 +500 @@
             break;
         }
+        case op_get_callee: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] op_get_callee %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_create_this: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            printf("[%4d] create_this %s %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data());
+            break;
+        }
         case op_convert_this: {
             int r0 = (++it)->u.operand;
@@ -1084 +1095 @@
             int argCount = (++it)->u.operand;
             int registerOffset = (++it)->u.operand;
-            int proto = (++it)->u.operand;
-            int thisRegister = (++it)->u.operand;
-            printf("[%4d] construct\t %s, %d, %d, %s, %s\n", location, registerName(exec, func).data(), argCount, registerOffset, registerName(exec, proto).data(), registerName(exec, thisRegister).data());
+            printf("[%4d] construct\t %s, %d, %d\n", location, registerName(exec, func).data(), argCount, registerOffset);
             break;
         }
@@ -1637 +1646 @@
         return false;
 
-    opcodeID = m_exceptionInfo->m_getByIdExceptionInfo[low - 1].isOpConstruct ? op_construct : op_instanceof;
+    opcodeID = m_exceptionInfo->m_getByIdExceptionInfo[low - 1].isOpCreateThis ? op_create_this : op_instanceof;
     return true;
 }

trunk/JavaScriptCore/bytecode/CodeBlock.h

@@ -98 +98 @@
     struct GetByIdExceptionInfo {
         unsigned bytecodeOffset : 31;
-        bool isOpConstruct : 1;
+        bool isOpCreateThis : 1;
     };
 

trunk/JavaScriptCore/bytecode/Opcode.h

@@ -43 +43 @@
         macro(op_init_arguments, 2) \
         macro(op_create_arguments, 2) \
+        macro(op_create_this, 3) \
+        macro(op_get_callee, 2) \
         macro(op_convert_this, 2) \
         \
@@ -165 +167 @@
         macro(op_method_check, 1) \
         \
-        macro(op_construct, 6) \
+        macro(op_construct, 4) \
         macro(op_strcat, 4) \
         macro(op_to_primitive, 3) \