Changeset 179887 in webkit for trunk/Source/JavaScriptCore/runtime/JSArray.cpp

Timestamp:

Feb 10, 2015, 3:16:36 PM (10 years ago)

Author:

[email protected]

Message:

op_call_varargs should only load the length once
​https://bugs.webkit.org/show_bug.cgi?id=141440
rdar://problem/19761683

Reviewed by Michael Saboff.

Refactors the pair of calls that set up the varargs frame so that the first call returns the
length, and the second call uses the length returned by the first one. It turns out that this
gave me an opportunity to shorten a lot of the code.

• interpreter/Interpreter.cpp:

(JSC::sizeFrameForVarargs):
(JSC::loadVarargs):
(JSC::setupVarargsFrame):
(JSC::setupVarargsFrameAndSetThis):

• interpreter/Interpreter.h:

(JSC::calleeFrameForVarargs):

• jit/CCallHelpers.h:

(JSC::CCallHelpers::setupArgumentsWithExecState):

• jit/JIT.h:
• jit/JITCall.cpp:

(JSC::JIT::compileSetupVarargsFrame):

• jit/JITCall32_64.cpp:

(JSC::JIT::compileSetupVarargsFrame):

• jit/JITInlines.h:

(JSC::JIT::callOperation):

• jit/JITOperations.cpp:
• jit/JITOperations.h:
• jit/SetupVarargsFrame.cpp:

(JSC::emitSetVarargsFrame):
(JSC::emitSetupVarargsFrameFastCase):

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

(JSC::LLInt::LLINT_SLOW_PATH_DECL):

• runtime/Arguments.cpp:

(JSC::Arguments::copyToArguments):

• runtime/Arguments.h:
• runtime/JSArray.cpp:

(JSC::JSArray::copyToArguments):

• runtime/JSArray.h:
• runtime/VM.h:
• tests/stress/call-varargs-length-effects.js: Added.

(foo):
(bar):

File:

• trunk/Source/JavaScriptCore/runtime/JSArray.cpp (modified) (3 diffs)

trunk/Source/JavaScriptCore/runtime/JSArray.cpp

@@ -1571 +1571 @@
 }
 
-void JSArray::copyToArguments(ExecState* exec, VirtualRegister firstElementDest, uint32_t copyLength, int32_t firstVarArgOffset)
-{
-    unsigned i = firstVarArgOffset;
+void JSArray::copyToArguments(ExecState* exec, VirtualRegister firstElementDest, unsigned offset, unsigned length)
+{
+    unsigned i = offset;
     WriteBarrier<Unknown>* vector;
     unsigned vectorEnd;
-    unsigned length = copyLength + firstVarArgOffset;
+    length += offset; // We like to think of the length as being our length, rather than the output length.
     ASSERT(length == this->length());
     switch (indexingType()) {
@@ -1603 +1603 @@
             if (v != v)
                 break;
-            exec->r(firstElementDest + i - firstVarArgOffset) = JSValue(JSValue::EncodeAsDouble, v);
+            exec->r(firstElementDest + i - offset) = JSValue(JSValue::EncodeAsDouble, v);
         }
         break;
@@ -1628 +1628 @@
         if (!v)
             break;
-        exec->r(firstElementDest + i - firstVarArgOffset) = v.get();
+        exec->r(firstElementDest + i - offset) = v.get();
     }
     
     for (; i < length; ++i) {
-        exec->r(firstElementDest + i - firstVarArgOffset) = get(exec, i);
+        exec->r(firstElementDest + i - offset) = get(exec, i);
         if (UNLIKELY(exec->vm().exception()))
             return;