Reviewers: Karl Klose,
Description:
ARM: Support %_SwapElements in the full compiler
Please review this at http://codereview.chromium.org/6597106/
SVN Base: http://v8.googlecode.com/svn/branches/bleeding_edge/
Affected files:
M src/arm/full-codegen-arm.cc
Index: src/arm/full-codegen-arm.cc
===================================================================
--- src/arm/full-codegen-arm.cc (revision 7028)
+++ src/arm/full-codegen-arm.cc (working copy)
@@ -3113,7 +3113,80 @@
VisitForStackValue(args->at(0));
VisitForStackValue(args->at(1));
VisitForStackValue(args->at(2));
+ Label done;
+ Label slow_case;
+ Register object = r0;
+ Register index1 = r1;
+ Register index2 = r2;
+ Register elements = r3;
+ Register scratch1 = r4;
+ Register scratch2 = r5;
+
+ __ ldr(object, MemOperand(sp, 2 * kPointerSize));
+ // Fetch the map and check if array is in fast case.
+ // Check that object doesn't require security checks and
+ // has no indexed interceptor.
+ __ CompareObjectType(object, scratch1, scratch2, FIRST_JS_OBJECT_TYPE);
+ __ b(lt, &slow_case);
+ // Map is now in scratch1.
+
+ __ ldrb(scratch2, FieldMemOperand(scratch1, Map::kBitFieldOffset));
+ __ tst(scratch2, Operand(KeyedLoadIC::kSlowCaseBitFieldMask));
+ __ b(ne, &slow_case);
+
+ // Check the object's elements are in fast case and writable.
+ __ ldr(elements, FieldMemOperand(object, JSObject::kElementsOffset));
+ __ ldr(scratch1, FieldMemOperand(elements, HeapObject::kMapOffset));
+ __ LoadRoot(ip, Heap::kFixedArrayMapRootIndex);
+ __ cmp(scratch1, ip);
+ __ b(ne, &slow_case);
+
+ // Check that both indices are smis.
+ __ ldr(index1, MemOperand(sp, 1 * kPointerSize));
+ __ ldr(index2, MemOperand(sp, 0));
+ __ JumpIfNotBothSmi(index1, index2, &slow_case);
+
+ // Check that both indices are valid.
+ __ ldr(scratch1, FieldMemOperand(object, JSArray::kLengthOffset));
+ __ cmp(scratch1, index1);
+ __ cmp(scratch1, index2, hi);
+ __ b(ls, &slow_case);
+
+ // Bring the address of the elements into index1 and index2.
+ __ add(scratch1, elements, Operand(FixedArray::kHeaderSize -
kHeapObjectTag));
+ __ add(index1,
+ scratch1,
+ Operand(index1, LSL, kPointerSizeLog2 - kSmiTagSize));
+ __ add(index2,
+ scratch1,
+ Operand(index2, LSL, kPointerSizeLog2 - kSmiTagSize));
+
+ // Swap elements.
+ __ ldr(scratch1, MemOperand(index1, 0));
+ __ ldr(scratch2, MemOperand(index2, 0)));
+ __ str(scratch1, MemOperand(index2, 0));
+ __ str(scratch2, MemOperand(index1, 0));
+
+ Label new_space;
+ __ InNewSpace(elements, scratch1, eq, &new_space);
+ // Possible optimization: do a check that both values are Smis
+ // (or them and test against Smi mask.)
+
+ __ mov(scratch1, elements);
+ __ RecordWriteHelper(elements, index1, scratch2);
+ __ RecordWriteHelper(scratch1, index2, scratch2); // scratch1 holds
elements.
+ __ bind(&done);
+
+ __ bind(&new_space);
+ // We are done. Drop elements from the stack, and return undefined.
+ __ Drop(3);
+ __ LoadRoot(r0, Heap::kUndefinedValueRootIndex);
+ __ jmp(&done);
+
+ __ bind(&slow_case);
__ CallRuntime(Runtime::kSwapElements, 3);
+
+ __ bind(&done);
context()->Plug(r0);
}
--
v8-dev mailing list
[email protected]
http://groups.google.com/group/v8-dev
