diff options
Diffstat (limited to 'lib/CodeGen/SplitKit.h')
| -rw-r--r-- | lib/CodeGen/SplitKit.h | 40 |
1 files changed, 31 insertions, 9 deletions
diff --git a/lib/CodeGen/SplitKit.h b/lib/CodeGen/SplitKit.h index 2ae760a..7174c0b 100644 --- a/lib/CodeGen/SplitKit.h +++ b/lib/CodeGen/SplitKit.h @@ -63,17 +63,22 @@ public: /// 1. | o---x | Internal to block. Variable is only live in this block. /// 2. |---x | Live-in, kill. /// 3. | o---| Def, live-out. - /// 4. |---x o---| Live-in, kill, def, live-out. + /// 4. |---x o---| Live-in, kill, def, live-out. Counted by NumGapBlocks. /// 5. |---o---o---| Live-through with uses or defs. - /// 6. |-----------| Live-through without uses. Transparent. + /// 6. |-----------| Live-through without uses. Counted by NumThroughBlocks. + /// + /// Two BlockInfo entries are created for template 4. One for the live-in + /// segment, and one for the live-out segment. These entries look as if the + /// block were split in the middle where the live range isn't live. + /// + /// Live-through blocks without any uses don't get BlockInfo entries. They + /// are simply listed in ThroughBlocks instead. /// struct BlockInfo { MachineBasicBlock *MBB; SlotIndex FirstUse; ///< First instr using current reg. SlotIndex LastUse; ///< Last instr using current reg. - SlotIndex Kill; ///< Interval end point inside block. - SlotIndex Def; ///< Interval start point inside block. - bool LiveThrough; ///< Live in whole block (Templ 5. or 6. above). + bool LiveThrough; ///< Live in whole block (Templ 5. above). bool LiveIn; ///< Current reg is live in. bool LiveOut; ///< Current reg is live out. }; @@ -91,12 +96,19 @@ private: /// UseBlocks - Blocks where CurLI has uses. SmallVector<BlockInfo, 8> UseBlocks; + /// NumGapBlocks - Number of duplicate entries in UseBlocks for blocks where + /// the live range has a gap. + unsigned NumGapBlocks; + /// ThroughBlocks - Block numbers where CurLI is live through without uses. BitVector ThroughBlocks; /// NumThroughBlocks - Number of live-through blocks. unsigned NumThroughBlocks; + /// DidRepairRange - analyze was forced to shrinkToUses(). + bool DidRepairRange; + SlotIndex computeLastSplitPoint(unsigned Num); // Sumarize statistics by counting instructions using CurLI. @@ -113,6 +125,11 @@ public: /// split. void analyze(const LiveInterval *li); + /// didRepairRange() - Returns true if CurLI was invalid and has been repaired + /// by analyze(). This really shouldn't happen, but sometimes the coalescer + /// can create live ranges that end in mid-air. + bool didRepairRange() const { return DidRepairRange; } + /// clear - clear all data structures so SplitAnalysis is ready to analyze a /// new interval. void clear(); @@ -139,7 +156,7 @@ public: /// getUseBlocks - Return an array of BlockInfo objects for the basic blocks /// where CurLI has uses. - ArrayRef<BlockInfo> getUseBlocks() { return UseBlocks; } + ArrayRef<BlockInfo> getUseBlocks() const { return UseBlocks; } /// getNumThroughBlocks - Return the number of through blocks. unsigned getNumThroughBlocks() const { return NumThroughBlocks; } @@ -150,9 +167,14 @@ public: /// getThroughBlocks - Return the set of through blocks. const BitVector &getThroughBlocks() const { return ThroughBlocks; } - /// countLiveBlocks - Return the number of blocks where li is live. - /// This is guaranteed to return the same number as getNumThroughBlocks() + - /// getUseBlocks().size() after calling analyze(li). + /// getNumLiveBlocks - Return the number of blocks where CurLI is live. + unsigned getNumLiveBlocks() const { + return getUseBlocks().size() - NumGapBlocks + getNumThroughBlocks(); + } + + /// countLiveBlocks - Return the number of blocks where li is live. This is + /// guaranteed to return the same number as getNumLiveBlocks() after calling + /// analyze(li). unsigned countLiveBlocks(const LiveInterval *li) const; typedef SmallPtrSet<const MachineBasicBlock*, 16> BlockPtrSet; |
