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Live interval reconstruction needs to account for this, and scour its maps to prevent dangling references. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63558 91177308-0d34-0410-b5e6-96231b3b80d8
755 lines
24 KiB
C++
755 lines
24 KiB
C++
//===-- LiveInterval.cpp - Live Interval Representation -------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements the LiveRange and LiveInterval classes. Given some
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// numbering of each the machine instructions an interval [i, j) is said to be a
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// live interval for register v if there is no instruction with number j' > j
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// such that v is live at j' abd there is no instruction with number i' < i such
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// that v is live at i'. In this implementation intervals can have holes,
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// i.e. an interval might look like [1,20), [50,65), [1000,1001). Each
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// individual range is represented as an instance of LiveRange, and the whole
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// interval is represented as an instance of LiveInterval.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/CodeGen/LiveInterval.h"
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#include "llvm/ADT/SmallSet.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/Support/Streams.h"
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#include "llvm/Target/TargetRegisterInfo.h"
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#include <algorithm>
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#include <ostream>
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using namespace llvm;
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// An example for liveAt():
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//
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// this = [1,4), liveAt(0) will return false. The instruction defining this
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// spans slots [0,3]. The interval belongs to an spilled definition of the
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// variable it represents. This is because slot 1 is used (def slot) and spans
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// up to slot 3 (store slot).
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//
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bool LiveInterval::liveAt(unsigned I) const {
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Ranges::const_iterator r = std::upper_bound(ranges.begin(), ranges.end(), I);
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if (r == ranges.begin())
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return false;
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--r;
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return r->contains(I);
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}
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// liveBeforeAndAt - Check if the interval is live at the index and the index
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// just before it. If index is liveAt, check if it starts a new live range.
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// If it does, then check if the previous live range ends at index-1.
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bool LiveInterval::liveBeforeAndAt(unsigned I) const {
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Ranges::const_iterator r = std::upper_bound(ranges.begin(), ranges.end(), I);
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if (r == ranges.begin())
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return false;
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--r;
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if (!r->contains(I))
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return false;
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if (I != r->start)
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return true;
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// I is the start of a live range. Check if the previous live range ends
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// at I-1.
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if (r == ranges.begin())
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return false;
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return r->end == I;
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}
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// overlaps - Return true if the intersection of the two live intervals is
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// not empty.
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//
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// An example for overlaps():
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//
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// 0: A = ...
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// 4: B = ...
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// 8: C = A + B ;; last use of A
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//
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// The live intervals should look like:
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//
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// A = [3, 11)
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// B = [7, x)
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// C = [11, y)
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//
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// A->overlaps(C) should return false since we want to be able to join
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// A and C.
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//
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bool LiveInterval::overlapsFrom(const LiveInterval& other,
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const_iterator StartPos) const {
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const_iterator i = begin();
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const_iterator ie = end();
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const_iterator j = StartPos;
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const_iterator je = other.end();
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assert((StartPos->start <= i->start || StartPos == other.begin()) &&
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StartPos != other.end() && "Bogus start position hint!");
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if (i->start < j->start) {
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i = std::upper_bound(i, ie, j->start);
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if (i != ranges.begin()) --i;
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} else if (j->start < i->start) {
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++StartPos;
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if (StartPos != other.end() && StartPos->start <= i->start) {
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assert(StartPos < other.end() && i < end());
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j = std::upper_bound(j, je, i->start);
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if (j != other.ranges.begin()) --j;
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}
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} else {
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return true;
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}
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if (j == je) return false;
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while (i != ie) {
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if (i->start > j->start) {
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std::swap(i, j);
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std::swap(ie, je);
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}
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if (i->end > j->start)
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return true;
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++i;
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}
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return false;
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}
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/// extendIntervalEndTo - This method is used when we want to extend the range
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/// specified by I to end at the specified endpoint. To do this, we should
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/// merge and eliminate all ranges that this will overlap with. The iterator is
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/// not invalidated.
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void LiveInterval::extendIntervalEndTo(Ranges::iterator I, unsigned NewEnd) {
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assert(I != ranges.end() && "Not a valid interval!");
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VNInfo *ValNo = I->valno;
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unsigned OldEnd = I->end;
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// Search for the first interval that we can't merge with.
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Ranges::iterator MergeTo = next(I);
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for (; MergeTo != ranges.end() && NewEnd >= MergeTo->end; ++MergeTo) {
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assert(MergeTo->valno == ValNo && "Cannot merge with differing values!");
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}
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// If NewEnd was in the middle of an interval, make sure to get its endpoint.
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I->end = std::max(NewEnd, prior(MergeTo)->end);
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// Erase any dead ranges.
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ranges.erase(next(I), MergeTo);
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// Update kill info.
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removeKills(ValNo, OldEnd, I->end-1);
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// If the newly formed range now touches the range after it and if they have
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// the same value number, merge the two ranges into one range.
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Ranges::iterator Next = next(I);
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if (Next != ranges.end() && Next->start <= I->end && Next->valno == ValNo) {
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I->end = Next->end;
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ranges.erase(Next);
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}
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}
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/// extendIntervalStartTo - This method is used when we want to extend the range
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/// specified by I to start at the specified endpoint. To do this, we should
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/// merge and eliminate all ranges that this will overlap with.
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LiveInterval::Ranges::iterator
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LiveInterval::extendIntervalStartTo(Ranges::iterator I, unsigned NewStart) {
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assert(I != ranges.end() && "Not a valid interval!");
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VNInfo *ValNo = I->valno;
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// Search for the first interval that we can't merge with.
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Ranges::iterator MergeTo = I;
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do {
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if (MergeTo == ranges.begin()) {
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I->start = NewStart;
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ranges.erase(MergeTo, I);
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return I;
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}
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assert(MergeTo->valno == ValNo && "Cannot merge with differing values!");
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--MergeTo;
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} while (NewStart <= MergeTo->start);
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// If we start in the middle of another interval, just delete a range and
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// extend that interval.
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if (MergeTo->end >= NewStart && MergeTo->valno == ValNo) {
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MergeTo->end = I->end;
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} else {
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// Otherwise, extend the interval right after.
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++MergeTo;
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MergeTo->start = NewStart;
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MergeTo->end = I->end;
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}
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ranges.erase(next(MergeTo), next(I));
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return MergeTo;
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}
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LiveInterval::iterator
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LiveInterval::addRangeFrom(LiveRange LR, iterator From) {
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unsigned Start = LR.start, End = LR.end;
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iterator it = std::upper_bound(From, ranges.end(), Start);
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// If the inserted interval starts in the middle or right at the end of
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// another interval, just extend that interval to contain the range of LR.
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if (it != ranges.begin()) {
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iterator B = prior(it);
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if (LR.valno == B->valno) {
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if (B->start <= Start && B->end >= Start) {
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extendIntervalEndTo(B, End);
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return B;
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}
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} else {
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// Check to make sure that we are not overlapping two live ranges with
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// different valno's.
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assert(B->end <= Start &&
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"Cannot overlap two LiveRanges with differing ValID's"
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" (did you def the same reg twice in a MachineInstr?)");
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}
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}
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// Otherwise, if this range ends in the middle of, or right next to, another
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// interval, merge it into that interval.
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if (it != ranges.end()) {
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if (LR.valno == it->valno) {
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if (it->start <= End) {
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it = extendIntervalStartTo(it, Start);
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// If LR is a complete superset of an interval, we may need to grow its
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// endpoint as well.
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if (End > it->end)
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extendIntervalEndTo(it, End);
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else if (End < it->end)
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// Overlapping intervals, there might have been a kill here.
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removeKill(it->valno, End);
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return it;
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}
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} else {
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// Check to make sure that we are not overlapping two live ranges with
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// different valno's.
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assert(it->start >= End &&
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"Cannot overlap two LiveRanges with differing ValID's");
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}
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}
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// Otherwise, this is just a new range that doesn't interact with anything.
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// Insert it.
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return ranges.insert(it, LR);
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}
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/// isInOneLiveRange - Return true if the range specified is entirely in the
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/// a single LiveRange of the live interval.
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bool LiveInterval::isInOneLiveRange(unsigned Start, unsigned End) {
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Ranges::iterator I = std::upper_bound(ranges.begin(), ranges.end(), Start);
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if (I == ranges.begin())
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return false;
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--I;
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return I->contains(Start) && I->contains(End-1);
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}
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/// removeRange - Remove the specified range from this interval. Note that
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/// the range must be in a single LiveRange in its entirety.
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void LiveInterval::removeRange(unsigned Start, unsigned End,
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bool RemoveDeadValNo) {
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// Find the LiveRange containing this span.
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Ranges::iterator I = std::upper_bound(ranges.begin(), ranges.end(), Start);
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assert(I != ranges.begin() && "Range is not in interval!");
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--I;
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assert(I->contains(Start) && I->contains(End-1) &&
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"Range is not entirely in interval!");
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// If the span we are removing is at the start of the LiveRange, adjust it.
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VNInfo *ValNo = I->valno;
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if (I->start == Start) {
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if (I->end == End) {
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removeKills(I->valno, Start, End);
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if (RemoveDeadValNo) {
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// Check if val# is dead.
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bool isDead = true;
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for (const_iterator II = begin(), EE = end(); II != EE; ++II)
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if (II != I && II->valno == ValNo) {
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isDead = false;
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break;
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}
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if (isDead) {
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// Now that ValNo is dead, remove it. If it is the largest value
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// number, just nuke it (and any other deleted values neighboring it),
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// otherwise mark it as ~1U so it can be nuked later.
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if (ValNo->id == getNumValNums()-1) {
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do {
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VNInfo *VNI = valnos.back();
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valnos.pop_back();
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VNI->~VNInfo();
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} while (!valnos.empty() && valnos.back()->def == ~1U);
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} else {
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ValNo->def = ~1U;
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}
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}
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}
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ranges.erase(I); // Removed the whole LiveRange.
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} else
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I->start = End;
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return;
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}
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// Otherwise if the span we are removing is at the end of the LiveRange,
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// adjust the other way.
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if (I->end == End) {
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removeKills(ValNo, Start, End);
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I->end = Start;
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return;
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}
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// Otherwise, we are splitting the LiveRange into two pieces.
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unsigned OldEnd = I->end;
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I->end = Start; // Trim the old interval.
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// Insert the new one.
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ranges.insert(next(I), LiveRange(End, OldEnd, ValNo));
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}
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/// removeValNo - Remove all the ranges defined by the specified value#.
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/// Also remove the value# from value# list.
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void LiveInterval::removeValNo(VNInfo *ValNo) {
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if (empty()) return;
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Ranges::iterator I = ranges.end();
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Ranges::iterator E = ranges.begin();
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do {
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--I;
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if (I->valno == ValNo)
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ranges.erase(I);
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} while (I != E);
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// Now that ValNo is dead, remove it. If it is the largest value
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// number, just nuke it (and any other deleted values neighboring it),
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// otherwise mark it as ~1U so it can be nuked later.
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if (ValNo->id == getNumValNums()-1) {
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do {
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VNInfo *VNI = valnos.back();
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valnos.pop_back();
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VNI->~VNInfo();
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} while (!valnos.empty() && valnos.back()->def == ~1U);
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} else {
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ValNo->def = ~1U;
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}
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}
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/// getLiveRangeContaining - Return the live range that contains the
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/// specified index, or null if there is none.
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LiveInterval::const_iterator
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LiveInterval::FindLiveRangeContaining(unsigned Idx) const {
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const_iterator It = std::upper_bound(begin(), end(), Idx);
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if (It != ranges.begin()) {
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--It;
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if (It->contains(Idx))
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return It;
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}
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return end();
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}
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LiveInterval::iterator
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LiveInterval::FindLiveRangeContaining(unsigned Idx) {
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iterator It = std::upper_bound(begin(), end(), Idx);
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if (It != begin()) {
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--It;
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if (It->contains(Idx))
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return It;
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}
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return end();
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}
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/// findDefinedVNInfo - Find the VNInfo that's defined at the specified index
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/// (register interval) or defined by the specified register (stack inteval).
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VNInfo *LiveInterval::findDefinedVNInfo(unsigned DefIdxOrReg) const {
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VNInfo *VNI = NULL;
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for (LiveInterval::const_vni_iterator i = vni_begin(), e = vni_end();
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i != e; ++i)
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if ((*i)->def == DefIdxOrReg) {
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VNI = *i;
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break;
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}
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return VNI;
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}
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/// join - Join two live intervals (this, and other) together. This applies
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/// mappings to the value numbers in the LHS/RHS intervals as specified. If
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/// the intervals are not joinable, this aborts.
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void LiveInterval::join(LiveInterval &Other, const int *LHSValNoAssignments,
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const int *RHSValNoAssignments,
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SmallVector<VNInfo*, 16> &NewVNInfo) {
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// Determine if any of our live range values are mapped. This is uncommon, so
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// we want to avoid the interval scan if not.
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bool MustMapCurValNos = false;
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unsigned NumVals = getNumValNums();
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unsigned NumNewVals = NewVNInfo.size();
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for (unsigned i = 0; i != NumVals; ++i) {
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unsigned LHSValID = LHSValNoAssignments[i];
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if (i != LHSValID ||
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(NewVNInfo[LHSValID] && NewVNInfo[LHSValID] != getValNumInfo(i)))
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MustMapCurValNos = true;
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}
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// If we have to apply a mapping to our base interval assignment, rewrite it
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// now.
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if (MustMapCurValNos) {
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// Map the first live range.
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iterator OutIt = begin();
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OutIt->valno = NewVNInfo[LHSValNoAssignments[OutIt->valno->id]];
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++OutIt;
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for (iterator I = OutIt, E = end(); I != E; ++I) {
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OutIt->valno = NewVNInfo[LHSValNoAssignments[I->valno->id]];
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// If this live range has the same value # as its immediate predecessor,
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// and if they are neighbors, remove one LiveRange. This happens when we
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// have [0,3:0)[4,7:1) and map 0/1 onto the same value #.
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if (OutIt->valno == (OutIt-1)->valno && (OutIt-1)->end == OutIt->start) {
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(OutIt-1)->end = OutIt->end;
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} else {
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if (I != OutIt) {
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OutIt->start = I->start;
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OutIt->end = I->end;
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}
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// Didn't merge, on to the next one.
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++OutIt;
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}
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}
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// If we merge some live ranges, chop off the end.
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ranges.erase(OutIt, end());
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}
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// Remember assignements because val# ids are changing.
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SmallVector<unsigned, 16> OtherAssignments;
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for (iterator I = Other.begin(), E = Other.end(); I != E; ++I)
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OtherAssignments.push_back(RHSValNoAssignments[I->valno->id]);
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// Update val# info. Renumber them and make sure they all belong to this
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// LiveInterval now. Also remove dead val#'s.
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unsigned NumValNos = 0;
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for (unsigned i = 0; i < NumNewVals; ++i) {
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VNInfo *VNI = NewVNInfo[i];
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if (VNI) {
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if (i >= NumVals)
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valnos.push_back(VNI);
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else
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valnos[NumValNos] = VNI;
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VNI->id = NumValNos++; // Renumber val#.
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}
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}
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if (NumNewVals < NumVals)
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valnos.resize(NumNewVals); // shrinkify
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// Okay, now insert the RHS live ranges into the LHS.
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iterator InsertPos = begin();
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unsigned RangeNo = 0;
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for (iterator I = Other.begin(), E = Other.end(); I != E; ++I, ++RangeNo) {
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// Map the valno in the other live range to the current live range.
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I->valno = NewVNInfo[OtherAssignments[RangeNo]];
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assert(I->valno && "Adding a dead range?");
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InsertPos = addRangeFrom(*I, InsertPos);
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}
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weight += Other.weight;
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if (Other.preference && !preference)
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preference = Other.preference;
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}
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/// MergeRangesInAsValue - Merge all of the intervals in RHS into this live
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/// interval as the specified value number. The LiveRanges in RHS are
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/// allowed to overlap with LiveRanges in the current interval, but only if
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/// the overlapping LiveRanges have the specified value number.
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void LiveInterval::MergeRangesInAsValue(const LiveInterval &RHS,
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VNInfo *LHSValNo) {
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// TODO: Make this more efficient.
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iterator InsertPos = begin();
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for (const_iterator I = RHS.begin(), E = RHS.end(); I != E; ++I) {
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// Map the valno in the other live range to the current live range.
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LiveRange Tmp = *I;
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Tmp.valno = LHSValNo;
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InsertPos = addRangeFrom(Tmp, InsertPos);
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}
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}
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/// MergeValueInAsValue - Merge all of the live ranges of a specific val#
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/// in RHS into this live interval as the specified value number.
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|
/// The LiveRanges in RHS are allowed to overlap with LiveRanges in the
|
|
/// current interval, it will replace the value numbers of the overlaped
|
|
/// live ranges with the specified value number.
|
|
void LiveInterval::MergeValueInAsValue(const LiveInterval &RHS,
|
|
const VNInfo *RHSValNo, VNInfo *LHSValNo) {
|
|
SmallVector<VNInfo*, 4> ReplacedValNos;
|
|
iterator IP = begin();
|
|
for (const_iterator I = RHS.begin(), E = RHS.end(); I != E; ++I) {
|
|
if (I->valno != RHSValNo)
|
|
continue;
|
|
unsigned Start = I->start, End = I->end;
|
|
IP = std::upper_bound(IP, end(), Start);
|
|
// If the start of this range overlaps with an existing liverange, trim it.
|
|
if (IP != begin() && IP[-1].end > Start) {
|
|
if (IP[-1].valno != LHSValNo) {
|
|
ReplacedValNos.push_back(IP[-1].valno);
|
|
IP[-1].valno = LHSValNo; // Update val#.
|
|
}
|
|
Start = IP[-1].end;
|
|
// Trimmed away the whole range?
|
|
if (Start >= End) continue;
|
|
}
|
|
// If the end of this range overlaps with an existing liverange, trim it.
|
|
if (IP != end() && End > IP->start) {
|
|
if (IP->valno != LHSValNo) {
|
|
ReplacedValNos.push_back(IP->valno);
|
|
IP->valno = LHSValNo; // Update val#.
|
|
}
|
|
End = IP->start;
|
|
// If this trimmed away the whole range, ignore it.
|
|
if (Start == End) continue;
|
|
}
|
|
|
|
// Map the valno in the other live range to the current live range.
|
|
IP = addRangeFrom(LiveRange(Start, End, LHSValNo), IP);
|
|
}
|
|
|
|
|
|
SmallSet<VNInfo*, 4> Seen;
|
|
for (unsigned i = 0, e = ReplacedValNos.size(); i != e; ++i) {
|
|
VNInfo *V1 = ReplacedValNos[i];
|
|
if (Seen.insert(V1)) {
|
|
bool isDead = true;
|
|
for (const_iterator I = begin(), E = end(); I != E; ++I)
|
|
if (I->valno == V1) {
|
|
isDead = false;
|
|
break;
|
|
}
|
|
if (isDead) {
|
|
// Now that V1 is dead, remove it. If it is the largest value number,
|
|
// just nuke it (and any other deleted values neighboring it), otherwise
|
|
// mark it as ~1U so it can be nuked later.
|
|
if (V1->id == getNumValNums()-1) {
|
|
do {
|
|
VNInfo *VNI = valnos.back();
|
|
valnos.pop_back();
|
|
VNI->~VNInfo();
|
|
} while (!valnos.empty() && valnos.back()->def == ~1U);
|
|
} else {
|
|
V1->def = ~1U;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/// MergeInClobberRanges - For any live ranges that are not defined in the
|
|
/// current interval, but are defined in the Clobbers interval, mark them
|
|
/// used with an unknown definition value.
|
|
void LiveInterval::MergeInClobberRanges(const LiveInterval &Clobbers,
|
|
BumpPtrAllocator &VNInfoAllocator) {
|
|
if (Clobbers.empty()) return;
|
|
|
|
// Find a value # to use for the clobber ranges. If there is already a value#
|
|
// for unknown values, use it.
|
|
// FIXME: Use a single sentinal number for these!
|
|
VNInfo *ClobberValNo = getNextValue(~0U, 0, VNInfoAllocator);
|
|
|
|
iterator IP = begin();
|
|
for (const_iterator I = Clobbers.begin(), E = Clobbers.end(); I != E; ++I) {
|
|
unsigned Start = I->start, End = I->end;
|
|
IP = std::upper_bound(IP, end(), Start);
|
|
|
|
// If the start of this range overlaps with an existing liverange, trim it.
|
|
if (IP != begin() && IP[-1].end > Start) {
|
|
Start = IP[-1].end;
|
|
// Trimmed away the whole range?
|
|
if (Start >= End) continue;
|
|
}
|
|
// If the end of this range overlaps with an existing liverange, trim it.
|
|
if (IP != end() && End > IP->start) {
|
|
End = IP->start;
|
|
// If this trimmed away the whole range, ignore it.
|
|
if (Start == End) continue;
|
|
}
|
|
|
|
// Insert the clobber interval.
|
|
IP = addRangeFrom(LiveRange(Start, End, ClobberValNo), IP);
|
|
}
|
|
}
|
|
|
|
/// MergeValueNumberInto - This method is called when two value nubmers
|
|
/// are found to be equivalent. This eliminates V1, replacing all
|
|
/// LiveRanges with the V1 value number with the V2 value number. This can
|
|
/// cause merging of V1/V2 values numbers and compaction of the value space.
|
|
VNInfo* LiveInterval::MergeValueNumberInto(VNInfo *V1, VNInfo *V2) {
|
|
assert(V1 != V2 && "Identical value#'s are always equivalent!");
|
|
|
|
// This code actually merges the (numerically) larger value number into the
|
|
// smaller value number, which is likely to allow us to compactify the value
|
|
// space. The only thing we have to be careful of is to preserve the
|
|
// instruction that defines the result value.
|
|
|
|
// Make sure V2 is smaller than V1.
|
|
if (V1->id < V2->id) {
|
|
copyValNumInfo(V1, V2);
|
|
std::swap(V1, V2);
|
|
}
|
|
|
|
// Merge V1 live ranges into V2.
|
|
for (iterator I = begin(); I != end(); ) {
|
|
iterator LR = I++;
|
|
if (LR->valno != V1) continue; // Not a V1 LiveRange.
|
|
|
|
// Okay, we found a V1 live range. If it had a previous, touching, V2 live
|
|
// range, extend it.
|
|
if (LR != begin()) {
|
|
iterator Prev = LR-1;
|
|
if (Prev->valno == V2 && Prev->end == LR->start) {
|
|
Prev->end = LR->end;
|
|
|
|
// Erase this live-range.
|
|
ranges.erase(LR);
|
|
I = Prev+1;
|
|
LR = Prev;
|
|
}
|
|
}
|
|
|
|
// Okay, now we have a V1 or V2 live range that is maximally merged forward.
|
|
// Ensure that it is a V2 live-range.
|
|
LR->valno = V2;
|
|
|
|
// If we can merge it into later V2 live ranges, do so now. We ignore any
|
|
// following V1 live ranges, as they will be merged in subsequent iterations
|
|
// of the loop.
|
|
if (I != end()) {
|
|
if (I->start == LR->end && I->valno == V2) {
|
|
LR->end = I->end;
|
|
ranges.erase(I);
|
|
I = LR+1;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Now that V1 is dead, remove it. If it is the largest value number, just
|
|
// nuke it (and any other deleted values neighboring it), otherwise mark it as
|
|
// ~1U so it can be nuked later.
|
|
if (V1->id == getNumValNums()-1) {
|
|
do {
|
|
VNInfo *VNI = valnos.back();
|
|
valnos.pop_back();
|
|
VNI->~VNInfo();
|
|
} while (valnos.back()->def == ~1U);
|
|
} else {
|
|
V1->def = ~1U;
|
|
}
|
|
|
|
return V2;
|
|
}
|
|
|
|
void LiveInterval::Copy(const LiveInterval &RHS,
|
|
BumpPtrAllocator &VNInfoAllocator) {
|
|
ranges.clear();
|
|
valnos.clear();
|
|
preference = RHS.preference;
|
|
weight = RHS.weight;
|
|
for (unsigned i = 0, e = RHS.getNumValNums(); i != e; ++i) {
|
|
const VNInfo *VNI = RHS.getValNumInfo(i);
|
|
VNInfo *NewVNI = getNextValue(~0U, 0, VNInfoAllocator);
|
|
copyValNumInfo(NewVNI, VNI);
|
|
}
|
|
for (unsigned i = 0, e = RHS.ranges.size(); i != e; ++i) {
|
|
const LiveRange &LR = RHS.ranges[i];
|
|
addRange(LiveRange(LR.start, LR.end, getValNumInfo(LR.valno->id)));
|
|
}
|
|
}
|
|
|
|
unsigned LiveInterval::getSize() const {
|
|
unsigned Sum = 0;
|
|
for (const_iterator I = begin(), E = end(); I != E; ++I)
|
|
Sum += I->end - I->start;
|
|
return Sum;
|
|
}
|
|
|
|
std::ostream& llvm::operator<<(std::ostream& os, const LiveRange &LR) {
|
|
return os << '[' << LR.start << ',' << LR.end << ':' << LR.valno->id << ")";
|
|
}
|
|
|
|
void LiveRange::dump() const {
|
|
cerr << *this << "\n";
|
|
}
|
|
|
|
void LiveInterval::print(std::ostream &OS,
|
|
const TargetRegisterInfo *TRI) const {
|
|
if (isStackSlot())
|
|
OS << "SS#" << getStackSlotIndex();
|
|
else if (TRI && TargetRegisterInfo::isPhysicalRegister(reg))
|
|
OS << TRI->getName(reg);
|
|
else
|
|
OS << "%reg" << reg;
|
|
|
|
OS << ',' << weight;
|
|
|
|
if (empty())
|
|
OS << " EMPTY";
|
|
else {
|
|
OS << " = ";
|
|
for (LiveInterval::Ranges::const_iterator I = ranges.begin(),
|
|
E = ranges.end(); I != E; ++I)
|
|
OS << *I;
|
|
}
|
|
|
|
// Print value number info.
|
|
if (getNumValNums()) {
|
|
OS << " ";
|
|
unsigned vnum = 0;
|
|
for (const_vni_iterator i = vni_begin(), e = vni_end(); i != e;
|
|
++i, ++vnum) {
|
|
const VNInfo *vni = *i;
|
|
if (vnum) OS << " ";
|
|
OS << vnum << "@";
|
|
if (vni->def == ~1U) {
|
|
OS << "x";
|
|
} else {
|
|
if (vni->def == ~0U)
|
|
OS << "?";
|
|
else
|
|
OS << vni->def;
|
|
unsigned ee = vni->kills.size();
|
|
if (ee || vni->hasPHIKill) {
|
|
OS << "-(";
|
|
for (unsigned j = 0; j != ee; ++j) {
|
|
OS << vni->kills[j];
|
|
if (j != ee-1)
|
|
OS << " ";
|
|
}
|
|
if (vni->hasPHIKill) {
|
|
if (ee)
|
|
OS << " ";
|
|
OS << "phi";
|
|
}
|
|
OS << ")";
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void LiveInterval::dump() const {
|
|
cerr << *this << "\n";
|
|
}
|
|
|
|
|
|
void LiveRange::print(std::ostream &os) const {
|
|
os << *this;
|
|
}
|