Changeset 49409 in webkit for trunk/JavaScriptCore/bytecompiler/Label.h

Timestamp:

Oct 9, 2009, 5:30:49 PM (16 years ago)

Author:

[email protected]

Message:

Eliminated some legacy bytecode weirdness.

Patch by Geoffrey Garen <​[email protected]> on 2009-10-09
Reviewed by Oliver Hunt.

Use vPC[x] subscripting instead of ++vPC to access instruction operands.
This is simpler, and often more efficient.

To support this, and to remove use of hard-coded offsets in bytecode and
JIT code generation and dumping, calculate jump offsets from the beginning
of an instruction, rather than the middle or end.

Also, use OPCODE_LENGTH instead of hard-coded constants for the sizes of
opcodes.

SunSpider reports no change in JIT mode, and a 1.01x speedup in Interpreter
mode.

• bytecode/CodeBlock.cpp:

(JSC::printConditionalJump):
(JSC::CodeBlock::dump):

• bytecompiler/BytecodeGenerator.cpp:

(JSC::BytecodeGenerator::emitJump):
(JSC::BytecodeGenerator::emitJumpIfTrue):
(JSC::BytecodeGenerator::emitJumpIfFalse):
(JSC::BytecodeGenerator::emitJumpIfNotFunctionCall):
(JSC::BytecodeGenerator::emitJumpIfNotFunctionApply):
(JSC::BytecodeGenerator::emitComplexJumpScopes):
(JSC::BytecodeGenerator::emitJumpScopes):
(JSC::BytecodeGenerator::emitNextPropertyName):
(JSC::BytecodeGenerator::emitCatch):
(JSC::BytecodeGenerator::emitJumpSubroutine):
(JSC::prepareJumpTableForImmediateSwitch):
(JSC::prepareJumpTableForCharacterSwitch):
(JSC::prepareJumpTableForStringSwitch):
(JSC::BytecodeGenerator::endSwitch):

• bytecompiler/Label.h:

(JSC::Label::setLocation):
(JSC::Label::bind):

• interpreter/Interpreter.cpp:

(JSC::Interpreter::resolve):
(JSC::Interpreter::resolveSkip):
(JSC::Interpreter::resolveGlobal):
(JSC::Interpreter::resolveBase):
(JSC::Interpreter::resolveBaseAndProperty):
(JSC::Interpreter::createExceptionScope):
(JSC::Interpreter::privateExecute):

• interpreter/Interpreter.h:
• jit/JIT.cpp:

(JSC::JIT::privateCompile):

• jit/JITArithmetic.cpp:

(JSC::JIT::emit_op_jnless):
(JSC::JIT::emitSlow_op_jnless):
(JSC::JIT::emit_op_jnlesseq):
(JSC::JIT::emitSlow_op_jnlesseq):
(JSC::JIT::emitBinaryDoubleOp):

• jit/JITOpcodes.cpp:

(JSC::JIT::emit_op_jmp):
(JSC::JIT::emit_op_loop):
(JSC::JIT::emit_op_loop_if_less):
(JSC::JIT::emitSlow_op_loop_if_less):
(JSC::JIT::emit_op_loop_if_lesseq):
(JSC::JIT::emitSlow_op_loop_if_lesseq):
(JSC::JIT::emit_op_loop_if_true):
(JSC::JIT::emitSlow_op_loop_if_true):
(JSC::JIT::emit_op_jfalse):
(JSC::JIT::emitSlow_op_jfalse):
(JSC::JIT::emit_op_jtrue):
(JSC::JIT::emitSlow_op_jtrue):
(JSC::JIT::emit_op_jeq_null):
(JSC::JIT::emit_op_jneq_null):
(JSC::JIT::emit_op_jneq_ptr):
(JSC::JIT::emit_op_jsr):
(JSC::JIT::emit_op_next_pname):
(JSC::JIT::emit_op_jmp_scopes):

File:

• trunk/JavaScriptCore/bytecompiler/Label.h (modified) (2 diffs)

trunk/JavaScriptCore/bytecompiler/Label.h

@@ -52 +52 @@
 
             unsigned size = m_unresolvedJumps.size();
-            for (unsigned i = 0; i < size; ++i) {
-                unsigned j = m_unresolvedJumps[i];
-                m_codeBlock->instructions()[j].u.operand = m_location - j;
-            }
+            for (unsigned i = 0; i < size; ++i)
+                m_codeBlock->instructions()[m_unresolvedJumps[i].second].u.operand = m_location - m_unresolvedJumps[i].first;
         }
 
-        int offsetFrom(int location) const
+        int bind(int opcode, int offset) const
         {
             if (m_location == invalidLocation) {
-                m_unresolvedJumps.append(location);
+                m_unresolvedJumps.append(std::make_pair(opcode, offset));
                 return 0;
             }
-            return m_location - location;
+            return m_location - opcode;
         }
 
@@ -78 +76 @@
 
     private:
-        typedef Vector<int, 8> JumpVector;
+        typedef Vector<std::pair<int, int>, 8> JumpVector;
 
         static const unsigned invalidLocation = UINT_MAX;