Mercurial > hg > graal-compiler
changeset 22833:054a187fc2cb
TraceRA: TraceLinearScanWalker: do not create empty intervals.
| author | Josef Eisl <josef.eisl@jku.at> |
|---|---|
| date | Thu, 08 Oct 2015 15:51:54 +0200 |
| parents | 44ebaa4e1ac1 |
| children | 7129686d9f18 |
| files | graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/trace/TraceLinearScanWalker.java |
| diffstat | 1 files changed, 13 insertions(+), 2 deletions(-) [+] |
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--- a/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/trace/TraceLinearScanWalker.java Thu Oct 08 15:28:33 2015 +0200 +++ b/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/trace/TraceLinearScanWalker.java Thu Oct 08 15:51:54 2015 +0200 @@ -396,7 +396,8 @@ // must calculate this before the actual split is performed and before split position is // moved to odd opId final int optimalSplitPosFinal; - if (allocator.isBlockBegin(optimalSplitPos)) { + boolean blockBegin = allocator.isBlockBegin(optimalSplitPos); + if (blockBegin) { assert (optimalSplitPos & 1) == 0 : "Block begins must be even: " + optimalSplitPos; // move position after the label (odd optId) optimalSplitPosFinal = optimalSplitPos + 1; @@ -405,7 +406,8 @@ optimalSplitPosFinal = (optimalSplitPos - 1) | 1; } - assert minSplitPos <= optimalSplitPosFinal && optimalSplitPosFinal <= maxSplitPos : "out of range"; + // TODO( je) better define what min split pos max split pos mean. + assert minSplitPos <= optimalSplitPosFinal && optimalSplitPosFinal <= maxSplitPos || minSplitPos == maxSplitPos && optimalSplitPosFinal == minSplitPos - 1 : "out of range"; assert optimalSplitPosFinal <= interval.to() : "cannot split after end of interval"; assert optimalSplitPosFinal > interval.from() : "cannot split at start of interval"; @@ -421,6 +423,15 @@ // "split pos must be even on block boundary"; assert (optimalSplitPosFinal & 1) == 1 : "split pos must be odd"; + // TODO (je) duplicate code. try to fold + if (optimalSplitPosFinal == interval.to() && interval.nextUsage(RegisterPriority.MustHaveRegister, minSplitPos) == Integer.MAX_VALUE) { + // the split position would be just before the end of the interval + // . no split at all necessary + if (Debug.isLogEnabled()) { + Debug.log("no split necessary because optimal split position is at end of interval"); + } + return; + } TraceInterval splitPart = interval.split(optimalSplitPosFinal, allocator); boolean moveNecessary = true;