Subzero: Register allocator performance improvements and simplifications.
This removes the redundancy between live ranges stored in the Variable and those stored in Liveness, by removing the Liveness copy. After liveness analysis, live ranges are constructed directly into the Variable.
Also, the LiveRangeWrapper is removed and Variable * is directly used instead. The original thought behind LiveRangeWrapper was that it could be extended to include live range splitting. However, when/if live range splitting is implemented, it will probably involve creating a new variable with its own live range, and carrying around some extra bookkeeping until the split is committed, so such a wrapper probably won't be needed.
BUG= none
R=jvoung@chromium.org
Review URL: https://codereview.chromium.org/656023002
diff --git a/src/IceCfgNode.cpp b/src/IceCfgNode.cpp
index 502bec5..767c9c3 100644
--- a/src/IceCfgNode.cpp
+++ b/src/IceCfgNode.cpp
@@ -357,16 +357,6 @@
return Changed;
}
-#ifndef NDEBUG
-namespace {
-
-bool comparePair(const LiveBeginEndMapEntry &A, const LiveBeginEndMapEntry &B) {
- return A.first == B.first;
-}
-
-} // end of anonymous namespace
-#endif // NDEBUG
-
// Now that basic liveness is complete, remove dead instructions that
// were tentatively marked as dead, and compute actual live ranges.
// It is assumed that within a single basic block, a live range begins
@@ -406,7 +396,7 @@
for (SizeT Src = 0; Src < NumSrcs; ++Src) {
Variable *Var = llvm::cast<Variable>(I->getSrc(Src));
InstNumberT InstNumber = I->getNumber();
- Liveness->addLiveRange(Var, InstNumber, InstNumber, 1);
+ Var->addLiveRange(InstNumber, InstNumber, 1);
}
}
}
@@ -424,9 +414,15 @@
std::sort(MapBegin.begin(), MapBegin.end());
std::sort(MapEnd.begin(), MapEnd.end());
// Verify there are no duplicates.
- assert(std::adjacent_find(MapBegin.begin(), MapBegin.end(), comparePair) ==
+ struct ComparePair {
+ bool operator()(const LiveBeginEndMapEntry &A,
+ const LiveBeginEndMapEntry &B) {
+ return A.first == B.first;
+ }
+ };
+ assert(std::adjacent_find(MapBegin.begin(), MapBegin.end(), ComparePair()) ==
MapBegin.end());
- assert(std::adjacent_find(MapEnd.begin(), MapEnd.end(), comparePair) ==
+ assert(std::adjacent_find(MapEnd.begin(), MapEnd.end(), ComparePair()) ==
MapEnd.end());
LivenessBV LiveInAndOut = LiveIn;
@@ -453,15 +449,15 @@
Variable *Var = Liveness->getVariable(i, this);
if (!Var->getIgnoreLiveness()) {
if (LB > LE) {
- Liveness->addLiveRange(Var, FirstInstNum, LE, 1);
- Liveness->addLiveRange(Var, LB, LastInstNum + 1, 1);
+ Var->addLiveRange(FirstInstNum, LE, 1);
+ Var->addLiveRange(LB, LastInstNum + 1, 1);
// Assert that Var is a global variable by checking that its
// liveness index is less than the number of globals. This
// ensures that the LiveInAndOut[] access is valid.
assert(i < Liveness->getNumGlobalVars());
LiveInAndOut[i] = false;
} else {
- Liveness->addLiveRange(Var, LB, LE, 1);
+ Var->addLiveRange(LB, LE, 1);
}
}
if (i == i1)
@@ -473,7 +469,7 @@
for (int i = LiveInAndOut.find_first(); i != -1;
i = LiveInAndOut.find_next(i)) {
Variable *Var = Liveness->getVariable(i, this);
- Liveness->addLiveRange(Var, FirstInstNum, LastInstNum + 1, 1);
+ Var->addLiveRange(FirstInstNum, LastInstNum + 1, 1);
}
}
