Author: [email protected]
Date: Fri May 15 05:43:00 2009
New Revision: 1968
Modified:
branches/bleeding_edge/src/codegen-inl.h
branches/bleeding_edge/src/codegen.h
branches/bleeding_edge/src/ia32/codegen-ia32.cc
Log:
Try to preallocate the scratch registers used for inlined keyed loads
to allow fast entry to the deferred code if possible.
Review URL: http://codereview.chromium.org/113457
Modified: branches/bleeding_edge/src/codegen-inl.h
==============================================================================
--- branches/bleeding_edge/src/codegen-inl.h (original)
+++ branches/bleeding_edge/src/codegen-inl.h Fri May 15 05:43:00 2009
@@ -43,6 +43,16 @@
}
+void DeferredCode::SetEntryFrame(Result* arg0, Result* arg1) {
+ ASSERT(generator()->has_valid_frame());
+ generator()->frame()->Push(arg0);
+ generator()->frame()->Push(arg1);
+ enter()->set_entry_frame(new VirtualFrame(generator()->frame()));
+ *arg1 = generator()->frame()->Pop();
+ *arg0 = generator()->frame()->Pop();
+}
+
+
//
-----------------------------------------------------------------------------
// Support for "structured" code comments.
//
Modified: branches/bleeding_edge/src/codegen.h
==============================================================================
--- branches/bleeding_edge/src/codegen.h (original)
+++ branches/bleeding_edge/src/codegen.h Fri May 15 05:43:00 2009
@@ -148,6 +148,7 @@
// results). This is optional, but should be done before branching
// or jumping to the deferred code.
inline void SetEntryFrame(Result* arg);
+ inline void SetEntryFrame(Result* arg0, Result* arg1);
JumpTarget* enter() { return &enter_; }
Modified: branches/bleeding_edge/src/ia32/codegen-ia32.cc
==============================================================================
--- branches/bleeding_edge/src/ia32/codegen-ia32.cc (original)
+++ branches/bleeding_edge/src/ia32/codegen-ia32.cc Fri May 15 05:43:00 2009
@@ -5415,24 +5415,30 @@
} else {
// Inline the inobject property case.
Comment cmnt(masm, "[ Inlined named property load");
+ DeferredReferenceGetNamedValue* deferred =
+ new DeferredReferenceGetNamedValue(cgen_, GetName());
Result receiver = cgen_->frame()->Pop();
receiver.ToRegister();
- // Preallocate the value register to ensure that there is no
- // spill emitted between the patch site label and the offset in
- // the load instruction and that all frames reaching the
- // deferred code are identical.
- Result value = cgen_->allocator()->Allocate();
- ASSERT(value.is_valid());
+ // Try to preallocate the value register so that all frames
+ // reaching the deferred code are identical.
+ Result value = cgen_->allocator()->AllocateWithoutSpilling();
+ if (value.is_valid()) {
+ deferred->SetEntryFrame(&receiver);
+ }
// Check that the receiver is a heap object.
__ test(receiver.reg(), Immediate(kSmiTagMask));
-
- DeferredReferenceGetNamedValue* deferred =
- new DeferredReferenceGetNamedValue(cgen_, GetName());
- deferred->SetEntryFrame(&receiver);
deferred->enter()->Branch(zero, &receiver, not_taken);
+ // Do not allocate the value register after binding the patch
+ // site label. The distance from the patch site to the offset
+ // must be constant.
+ if (!value.is_valid()) {
+ value = cgen_->allocator()->Allocate();
+ ASSERT(value.is_valid());
+ }
+
__ bind(deferred->patch_site());
// This is the map check instruction that will be patched (so we
can't
// use the double underscore macro that may insert instructions).
@@ -5482,6 +5488,14 @@
key.ToRegister();
receiver.ToRegister();
+ // Try to preallocate the elements and index scratch registers
+ // so that all frames reaching the deferred code are identical.
+ Result elements = cgen_->allocator()->AllocateWithoutSpilling();
+ Result index = cgen_->allocator()->AllocateWithoutSpilling();
+ if (elements.is_valid() && index.is_valid()) {
+ deferred->SetEntryFrame(&receiver, &key);
+ }
+
// Check that the receiver is not a smi (only needed if this
// is not a load from the global context) and that it has the
// expected map.
@@ -5505,8 +5519,10 @@
// Get the elements array from the receiver and check that it
// is not a dictionary.
- Result elements = cgen_->allocator()->Allocate();
- ASSERT(elements.is_valid());
+ if (!elements.is_valid()) {
+ elements = cgen_->allocator()->Allocate();
+ ASSERT(elements.is_valid());
+ }
__ mov(elements.reg(),
FieldOperand(receiver.reg(), JSObject::kElementsOffset));
__ cmp(FieldOperand(elements.reg(), HeapObject::kMapOffset),
@@ -5515,8 +5531,10 @@
// Shift the key to get the actual index value and check that
// it is within bounds.
- Result index = cgen_->allocator()->Allocate();
- ASSERT(index.is_valid());
+ if (!index.is_valid()) {
+ index = cgen_->allocator()->Allocate();
+ ASSERT(index.is_valid());
+ }
__ mov(index.reg(), key.reg());
__ sar(index.reg(), kSmiTagSize);
__ cmp(index.reg(),
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