AuroraMiddleware/v8
1
0
Fork 0
Code Issues 2 Pull Requests Releases Wiki Activity

Drop unused accumulated first time changes/depends.

Browse Source 
R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/135503004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19213 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
bmeurer@chromium.org 2014-02-10 08:59:51 +00:00
parent ff1c294cf9
commit e05dbf4e22
2 changed files with 3 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
src/hydrogen-gvn.cc
View File

@ -535,13 +535,9 @@ void HGlobalValueNumberingPhase::LoopInvariantCodeMotion() {
block->block_id(),
GetGVNFlagsString(side_effects).get());
GVNFlagSet accumulated_first_time_depends;
GVNFlagSet accumulated_first_time_changes;
HBasicBlock* last = block->loop_information()->GetLastBackEdge();
for (int j = block->block_id(); j <= last->block_id(); ++j) {
ProcessLoopBlock(graph()->blocks()->at(j), block, side_effects,
&accumulated_first_time_depends,
&accumulated_first_time_changes);
ProcessLoopBlock(graph()->blocks()->at(j), block, side_effects);
}
}
}
@ -551,9 +547,7 @@ void HGlobalValueNumberingPhase::LoopInvariantCodeMotion() {
void HGlobalValueNumberingPhase::ProcessLoopBlock(
HBasicBlock* block,
HBasicBlock* loop_header,
GVNFlagSet loop_kills,
GVNFlagSet* first_time_depends,
GVNFlagSet* first_time_changes) {
GVNFlagSet loop_kills) {
HBasicBlock* pre_header = loop_header->predecessors()->at(0);
GVNFlagSet depends_flags = HValue::ConvertChangesToDependsFlags(loop_kills);
TRACE_GVN_2("Loop invariant motion for B%d %s\n",
@ -562,7 +556,6 @@ void HGlobalValueNumberingPhase::ProcessLoopBlock(
HInstruction* instr = block->first();
while (instr != NULL) {
HInstruction* next = instr->next();
bool hoisted = false;
if (instr->CheckFlag(HValue::kUseGVN)) {
TRACE_GVN_4("Checking instruction %d (%s) %s. Loop %s\n",
instr->id(),
@ -589,26 +582,9 @@ void HGlobalValueNumberingPhase::ProcessLoopBlock(
instr->Unlink();
instr->InsertBefore(pre_header->end());
if (instr->HasSideEffects()) removed_side_effects_ = true;
hoisted = true;
}
}
}
if (!hoisted) {
// If an instruction is not hoisted, we have to account for its side
// effects when hoisting later HTransitionElementsKind instructions.
GVNFlagSet previous_depends = *first_time_depends;
GVNFlagSet previous_changes = *first_time_changes;
first_time_depends->Add(instr->DependsOnFlags());
first_time_changes->Add(instr->ChangesFlags());
if (!(previous_depends == *first_time_depends)) {
TRACE_GVN_1("Updated first-time accumulated %s\n",
GetGVNFlagsString(*first_time_depends).get());
}
if (!(previous_changes == *first_time_changes)) {
TRACE_GVN_1("Updated first-time accumulated %s\n",
GetGVNFlagsString(*first_time_changes).get());
}
}
instr = next;
}
}

4
src/hydrogen-gvn.h
View File

@ -52,9 +52,7 @@ class HGlobalValueNumberingPhase : public HPhase {
void LoopInvariantCodeMotion();
void ProcessLoopBlock(HBasicBlock* block,
HBasicBlock* before_loop,
GVNFlagSet loop_kills,
GVNFlagSet* accumulated_first_time_depends,
GVNFlagSet* accumulated_first_time_changes);
GVNFlagSet loop_kills);
bool AllowCodeMotion();
bool ShouldMove(HInstruction* instr, HBasicBlock* loop_header);