JDK-8216580 : Fix generation of VNNI vector code by allowing adjacent LoadS nodes to be isomorphic
  • Type: Enhancement
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 12,13
  • Priority: P3
  • Status: Resolved
  • Resolution: Fixed
  • CPU: x86
  • Submitted: 2019-01-11
  • Updated: 2019-03-13
  • Resolved: 2019-03-05
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JDK 13
13 b11Fixed
Related Reports
Relates :  
JDK-8216050 - Superword optimization fails with assert(0 <= i && i < _len) failed: illegal index
Relates :  
JDK-8220211 - Small update to Fix generation of VNNI vector code by allowing adjacent LoadS nodes to be isomorphic (JDK-8216580)
Relates :  
JDK-8214751 - X86: Support for VNNI Instructions
Description
Fix generation of vector code by allowing adjacent LoadS nodes to be isomorphic when they have different control RangeCheck nodes for a[i] and a[i+1] accesses in same MulAddS2I node.
Separating it from JDK-8216050 in a new bug.
Comments
Webrev with an added check against NULL. http://cr.openjdk.java.net/~vdeshpande/8216580/webrev.03/
05-03-2019
My tier1-tier3 testing passed with few unrelated failures. Note, we don't have VNNI machines so the code is not exercised. [~vdeshpande] is running testing on VNNI machine.
01-03-2019
http://cr.openjdk.java.net/~vdeshpande/8216580/webrev.02/
01-03-2019
Fixed parentheses at 1225,1226 http://cr.openjdk.java.net/~vdeshpande/8216580/webrev.01/
15-01-2019
Hi Rahul, The jtreg test Vec_MulAddS2I.java is the failing case. It does not generate wrong code, but it does not get vectorized as it cannot pack the adjacent LoadS nodes.
15-01-2019
Shouldn't this be an enhancement?
14-01-2019
initial ILW = wrong vector code generation; not commonly reported!; disable vectorization = HLM = P3 Hi [~vdeshpande], please add a sample failing test case if any. Thanks.
14-01-2019
Fix generation of vector code by allowing adjacent LoadS nodes to be isomorphic when they have different control RangeCheck nodes for a[i] and a[i+1] accesses in same MulAddS2I node. Webrev: http://cr.openjdk.java.net/~vdeshpande/8216580/webrev.00/
11-01-2019