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/IceCfg.cpp b/src/IceCfg.cpp
index c30e02a..b9deb01 100644
--- a/src/IceCfg.cpp
+++ b/src/IceCfg.cpp
@@ -219,32 +219,21 @@
// "r=arg1+arg2", both args may be assigned the same register.
for (SizeT I = 0; I < Args.size(); ++I) {
Variable *Arg = Args[I];
- if (!Live->getLiveRange(Arg).isEmpty()) {
+ if (!Arg->getLiveRange().isEmpty()) {
// Add live range [-1,0) with weight 0. TODO: Here and below,
// use better symbolic constants along the lines of
// Inst::NumberDeleted and Inst::NumberSentinel instead of -1
// and 0.
- Live->addLiveRange(Arg, -1, 0, 0);
+ Arg->addLiveRange(-1, 0, 0);
}
// Do the same for i64 args that may have been lowered into i32
// Lo and Hi components.
Variable *Lo = Arg->getLo();
- if (Lo && !Live->getLiveRange(Lo).isEmpty())
- Live->addLiveRange(Lo, -1, 0, 0);
+ if (Lo && !Lo->getLiveRange().isEmpty())
+ Lo->addLiveRange(-1, 0, 0);
Variable *Hi = Arg->getHi();
- if (Hi && !Live->getLiveRange(Hi).isEmpty())
- Live->addLiveRange(Hi, -1, 0, 0);
- }
- // Copy Liveness::LiveRanges into individual variables. TODO:
- // Remove Variable::LiveRange and redirect to
- // Liveness::LiveRanges. TODO: make sure Variable weights
- // are applied properly.
- SizeT NumVars = Variables.size();
- for (SizeT i = 0; i < NumVars; ++i) {
- Variable *Var = Variables[i];
- Var->setLiveRange(Live->getLiveRange(Var));
- if (Var->getWeight().isInf())
- Var->setLiveRangeInfiniteWeight();
+ if (Hi && !Hi->getLiveRange().isEmpty())
+ Hi->addLiveRange(-1, 0, 0);
}
}
}
