Reviewers: danno, Massi,
Message:
Around ~11% in imaging-desaturate on my machine.
Zheng Liu
[email protected]
Description:
Don't reference transitioned elements in hoisted instructions.
Test=imaging-desaturate slightly faster
Please review this at http://codereview.chromium.org/10544133/
SVN Base: http://v8.googlecode.com/svn/branches/bleeding_edge/
Affected files:
M src/hydrogen.cc
Index: src/hydrogen.cc
===================================================================
--- src/hydrogen.cc (revision 11791)
+++ src/hydrogen.cc (working copy)
@@ -1512,6 +1512,7 @@
GVNFlagSet loop_kills,
GVNFlagSet* accumulated_first_time_depends,
GVNFlagSet* accumulated_first_time_changes);
+ void PostProcessLoopPreHeader(HBasicBlock* pre_header);
bool AllowCodeMotion();
bool ShouldMove(HInstruction* instr, HBasicBlock* loop_header);
@@ -1689,6 +1690,7 @@
&accumulated_first_time_depends,
&accumulated_first_time_changes);
}
+ PostProcessLoopPreHeader(block->predecessors()->at(0));
}
}
}
@@ -1801,7 +1803,27 @@
}
}
+void HGlobalValueNumberer::PostProcessLoopPreHeader(HBasicBlock*
pre_header) {
+ HInstruction* instr = pre_header->first();
+ while (instr != NULL) {
+ HInstruction* next = instr->next();
+ if (instr->IsTransitionElementsKind()) {
+ HValue* old_elems = instr->OperandAt(0), *new_elems = instr;
+ HInstruction* current = next;
+ while (current != NULL) {
+ for (int i = 0; i < current->OperandCount(); ++i) {
+ if (current->OperandAt(i) == old_elems) {
+ current->SetOperandAt(i, new_elems);
+ }
+ }
+ current = current->next();
+ }
+ }
+ instr = next;
+ }
+}
+
bool HGlobalValueNumberer::AllowCodeMotion() {
return info()->shared_info()->opt_count() + 1 <
Compiler::kDefaultMaxOptCount;
}
--
v8-dev mailing list
[email protected]
http://groups.google.com/group/v8-dev
