RFR: 8270307: C2: assert(false) failed: bad AD file after JDK-8267687

[Yi Yang]

One input of ConvI2L becomes Top, which causes all nodes in the chain becoming Top, but this CMoveLNode does not change, only its input becomes Top.


  Pop  2146  CMoveL  === _  351  1  2149  [[ 2182  2187 ]]   Type:long !orig=810,696,[439],288 !jvms: Test::vMeth @ bci:78 (line 8)
BreakAtNode: _idx=2461 _debug_idx=102702461 orig._idx=2146 orig._debug_idx=92502146
<               < 2146  CMoveL  === _ _  1 _  [[]]   Type:long !orig=810,696,[439],288 !jvms: Test::vMeth @ bci:78 (line 8)
> long           2461  CMoveL  === _  2458  2149  1  [[ 2187  2182 ]]   Type:long !orig=2146,810,696,[439],288 !jvms: Test::vMeth @ bci:78 (line 8)


This CMoveLNode(CMove Binary(.. ..) (Binary .. Con#Top)) can not match any rules in instruction selection phase and finally hits the assert.

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Commit messages:
 - crash

Changes: https://git.openjdk.java.net/jdk/pull/4796/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=4796&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8270307
  Stats: 62 lines in 2 files changed: 62 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4796.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4796/head:pull/4796

PR: https://git.openjdk.java.net/jdk/pull/4796