Improve comments a bit
Use an explicit LiveRange class to represent ranges instead of an std::pair.
This is a minor cleanup, but is really intended to make a future patch simpler
and less invasive.
Alkis, could you please take a look at LiveInterval::liveAt? I suspect that
you can add an operator<(unsigned) to LiveRange, allowing us to speed up the
upper_bound call by quite a bit (this would also apply to other callers of
upper/lower_bound). I would do it myself, but I still don't understand that
crazy liveAt function, despite the comment. :)
Basically I would like to see this:
LiveRange dummy(index, index+1);
Ranges::const_iterator r = std::upper_bound(ranges.begin(),
ranges.end(),
dummy);
Turn into:
Ranges::const_iterator r = std::upper_bound(ranges.begin(),
ranges.end(),
index);
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15130 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveIntervalAnalysis.h b/lib/CodeGen/LiveIntervalAnalysis.h
index a78aed1..a70deff 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.h
+++ b/lib/CodeGen/LiveIntervalAnalysis.h
@@ -29,9 +29,29 @@
class MRegisterInfo;
class VirtRegMap;
+ /// LiveRange structure - This represents a simple register range in the
+ /// program, with an inclusive start point and an exclusive end point.
+ /// These ranges are rendered as [start,end).
+ struct LiveRange {
+ unsigned start; // Start point of the interval (inclusive)
+ unsigned end; // End point of the interval (exclusive)
+ LiveRange(unsigned S, unsigned E) : start(S), end(E) {
+ assert(S < E && "Cannot create empty or backwards range");
+ }
+
+ bool operator<(const LiveRange &LR) const {
+ return start < LR.start || (start == LR.start && end < LR.end);
+ }
+ bool operator==(const LiveRange &LR) const {
+ return start == LR.start && end == LR.end;
+ }
+ private:
+ LiveRange(); // DO NOT IMPLEMENT
+ };
+ std::ostream& operator<<(std::ostream& os, const LiveRange &LR);
+
struct LiveInterval {
- typedef std::pair<unsigned, unsigned> Range;
- typedef std::vector<Range> Ranges;
+ typedef std::vector<LiveRange> Ranges;
unsigned reg; // the register of this interval
float weight; // weight of this interval:
// (number of uses *10^loopDepth)
@@ -44,14 +64,17 @@
bool spilled() const;
+ /// start - Return the lowest numbered slot covered by interval.
unsigned start() const {
assert(!empty() && "empty interval for register");
- return ranges.front().first;
+ return ranges.front().start;
}
+ /// end - return the maximum point of the interval of the whole,
+ /// exclusive.
unsigned end() const {
assert(!empty() && "empty interval for register");
- return ranges.back().second;
+ return ranges.back().end;
}
bool expiredAt(unsigned index) const {
@@ -62,7 +85,7 @@
bool overlaps(const LiveInterval& other) const;
- void addRange(unsigned start, unsigned end);
+ void addRange(LiveRange R);
void join(const LiveInterval& other);