Changeset 149247 in webkit for trunk/Source/JavaScriptCore/jit/JITOpcodes.cpp

Timestamp:

Apr 27, 2013, 4:14:04 PM (12 years ago)

Author:

[email protected]

Message:

Cleaned up pre/post inc/dec in bytecode
​https://bugs.webkit.org/show_bug.cgi?id=115222

Reviewed by Filip Pizlo.

Source/JavaScriptCore:

A few related changes here:

(*) Removed post_inc and post_dec. The two-result form was awkward to
reason about. Being explicit about the intermediate mov and to_number
reduces DFG overhead, removes some fragile ASSERTs from the DFG, and
fixes a const bug. Plus, we get to blow away 262 lines of code.

(*) Renamed pre_inc and pre_dec to inc and dec, since there's only one
version now.

(*) Renamed to_jsnumber to to_number, to match the ECMA name.

(*) Tightened up the codegen and runtime support for to_number.

• JavaScriptCore.order: Order!

• bytecode/CodeBlock.cpp:

(JSC::CodeBlock::dumpBytecode):

• bytecode/Opcode.h:

(JSC::padOpcodeName):

• bytecompiler/BytecodeGenerator.cpp:

(JSC::BytecodeGenerator::emitInc):
(JSC::BytecodeGenerator::emitDec):

• bytecompiler/BytecodeGenerator.h:

(JSC::BytecodeGenerator::emitToNumber):
(BytecodeGenerator): Removed post_inc and post_dec.

• bytecompiler/NodesCodegen.cpp:

(JSC::emitPreIncOrDec): Updated for rename.

(JSC::emitPostIncOrDec): Issue an explicit mov and to_number when needed.
These are rare, and they boil away in the DFG.

(JSC::PostfixNode::emitResolve):
(JSC::PrefixNode::emitResolve): For const, use an explicit mov instead
of any special forms. This fixes a bug where we would do string
add/subtract instead of number.

• dfg/DFGByteCodeParser.cpp:

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

• dfg/DFGCapabilities.h:

(JSC::DFG::canCompileOpcode):

• jit/JIT.cpp:

(JSC::JIT::privateCompileMainPass):
(JSC::JIT::privateCompileSlowCases):

• jit/JIT.h:
• jit/JITArithmetic.cpp:

(JSC::JIT::emit_op_inc):
(JSC::JIT::emitSlow_op_inc):
(JSC::JIT::emit_op_dec):
(JSC::JIT::emitSlow_op_dec):

• jit/JITArithmetic32_64.cpp:

(JSC::JIT::emit_op_inc):
(JSC::JIT::emitSlow_op_inc):
(JSC::JIT::emit_op_dec):
(JSC::JIT::emitSlow_op_dec): Removed post_inc/dec, and updated for renames.

• jit/JITOpcodes.cpp:

(JSC::JIT::emit_op_to_number):
(JSC::JIT::emitSlow_op_to_number): Removed a test for number cells. There's
no such thing!

• jit/JITOpcodes32_64.cpp:

(JSC::JIT::emit_op_to_number): Use LowestTag to avoid making assumptions
about the lowest valued tag.

(JSC::JIT::emitSlow_op_to_number): Updated for renames.

• jit/JITStubs.cpp:

(JSC::DEFINE_STUB_FUNCTION):

• jit/JITStubs.h:
• llint/LLIntSlowPaths.cpp:

(JSC::LLInt::LLINT_SLOW_PATH_DECL):

• llint/LLIntSlowPaths.h:
• llint/LowLevelInterpreter32_64.asm:
• llint/LowLevelInterpreter64.asm:
• parser/NodeConstructors.h:

(JSC::UnaryPlusNode::UnaryPlusNode): Removed post_inc/dec, and updated for renames.

• runtime/Operations.cpp:

(JSC::jsIsObjectType): Removed a test for number cells. There's
no such thing!

LayoutTests:

• fast/js/const-expected.txt:
• fast/js/resources/const.js: Added tests for some const cases we used

to get wrong.

File:

• trunk/Source/JavaScriptCore/jit/JITOpcodes.cpp (modified) (2 diffs)

trunk/Source/JavaScriptCore/jit/JITOpcodes.cpp

@@ -685 +685 @@
 }
 
-void JIT::emit_op_to_jsnumber(Instruction* currentInstruction)
+void JIT::emit_op_to_number(Instruction* currentInstruction)
 {
     int srcVReg = currentInstruction[2].u.operand;
     emitGetVirtualRegister(srcVReg, regT0);
     
-    Jump wasImmediate = emitJumpIfImmediateInteger(regT0);
-
-    emitJumpSlowCaseIfNotJSCell(regT0, srcVReg);
-    loadPtr(Address(regT0, JSCell::structureOffset()), regT2);
-    addSlowCase(branch8(NotEqual, Address(regT2, Structure::typeInfoTypeOffset()), TrustedImm32(NumberType)));
-    
-    wasImmediate.link(this);
+    addSlowCase(emitJumpIfNotImmediateNumber(regT0));
 
     emitPutVirtualRegister(currentInstruction[1].u.operand);
@@ -1140 +1134 @@
 }
 
-void JIT::emitSlow_op_to_jsnumber(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
-{
-    linkSlowCaseIfNotJSCell(iter, currentInstruction[2].u.operand);
-    linkSlowCase(iter);
-
-    JITStubCall stubCall(this, cti_op_to_jsnumber);
+void JIT::emitSlow_op_to_number(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+{
+    linkSlowCase(iter);
+
+    JITStubCall stubCall(this, cti_op_to_number);
     stubCall.addArgument(regT0);
     stubCall.call(currentInstruction[1].u.operand);