JDK-8366890 : C2: Split through phi printing with TraceLoopOpts misses line break
  • Type: Bug
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 26
  • Priority: P5
  • Status: Resolved
  • Resolution: Fixed
  • Submitted: 2025-09-04
  • Updated: 2025-09-05
  • Resolved: 2025-09-05
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JDK 26
26 masterFixed
Related Reports
Relates :  
JDK-8356176 - C2 MemorySegment: missing RCE with byteSize() in Loop Exit Check inside the for Expression
Description
JDK-8356176 added new printing code for TraceLoopOpts when splitting nodes through a phi but missed a line break:

  if (TraceLoopOpts) {
    tty->print("Split %d %s through %d Phi in %d %s",
               n->_idx, n->Name(), phi->_idx, region->_idx, region->Name());
  }

This will result in:

Split 974 CmpI through 1465 Phi in 953 RegionSplit 474 Bool through 1468 Phi in 953 RegionSplit-If

instead of 

Split 974 CmpI through 1465 Phi in 953 RegionSplit 474 Bool through 1468 Phi in 953 Region
Split-If
Comments
Changeset: ceacf6f7 Branch: master Author: Christian Hagedorn <chagedorn@openjdk.org> Date: 2025-09-05 15:26:13 +0000 URL: https://git.openjdk.org/jdk/commit/ceacf6f7852514dc9877cfe284f9550c179d913a
05-09-2025
A pull request was submitted for review. Branch: master URL: https://git.openjdk.org/jdk/pull/27092 Date: 2025-09-04 12:44:43 +0000
04-09-2025
ILW = Printing is off, only with TraceLoopOpts, no workaround = LLH = P5
04-09-2025