hg: jdk/jdk: 8244719: CTW: C2 compilation fails with "assert(!VerifyHashTableKeys || _hash_lock == 0) failed: remove node from hash table before modifying it"

[christian.hagedorn at oracle.com]

Changeset: e8d34f3f6833
Author:    chagedorn
Date:      2020-06-10 17:56 +0200
URL:       https://hg.openjdk.java.net/jdk/jdk/rev/e8d34f3f6833

8244719: CTW: C2 compilation fails with "assert(!VerifyHashTableKeys || _hash_lock == 0) failed: remove node from hash table before modifying it"
Summary: Fix Parse::Block::init_graph() to also count predecessors for exception blocks because they can have a direct bytecode jump to them resulting in this assertion failure.
Reviewed-by: kvn, thartmann

! src/hotspot/share/opto/parse1.cpp
+ test/hotspot/jtreg/compiler/parsing/TestExceptionBlockWithPredecessors.jasm
+ test/hotspot/jtreg/compiler/parsing/TestExceptionBlockWithPredecessorsMain.java