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I managed to extract a dump of the IR graph from the core file and I can see what's causing the crash: the IR graph is incorrect but unless I can reproduce the failure I can't really say what caused the IR graph to become incorrect (i.e. what previous optimization broke the graph).
Using the serviceability agent I managed to extract a replay file and a jar of the loaded classes from the core file but when I replay the compilation, I don't get a crash. So either, the replay or the jar are bad or I'm missing some command line argument or this is one of the rare cases where the compilation cannot be replayed reliably.
User can prevent the crash by excluding a dispatching loop routine from jit generation. Immediate backtrace is: ... #6 <signal handler called> #7 in (this=0x7f8c89efb410, n=0x7f8c711f5110) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/node.hpp:365 #8 idom_no_update (this=0x7f8c89efb410, n=0x7f8c711f5110) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/loopnode.hpp:732 #9 idom (this=0x7f8c89efb410, n=0x7f8c711f5110) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/loopnode.hpp:741 #10 PhaseIdealLoop::build_loop_late_post (this=0x7f8c89efb410, n=0x7f8c711f5110) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/loopnode.cpp:3567 #11 0x00007f8d09bc19bb in PhaseIdealLoop::build_loop_late (this=0x7f8c89efb410, visited=..., worklist=..., nstack=...) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/loopnode.cpp:3455 #12 0x00007f8d09bc4a80 in PhaseIdealLoop::build_and_optimize (this=0x7f8d04881f90, do_split_ifs=false, skip_loop_opts=true) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/loopnode.cpp:2281 #13 0x00007f8d0989a12c in Compile::Optimize (this=0x7f8c89efcc00) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/compile.cpp:2181 ... all threads, but #211 on blocking libc calls. ... [Switching to thread 211 (Thread 0x7f8c89dfd700 (LWP 7979))]#0 remove (this=0x7f8c89df95b0, a=<value optimized out>) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/indexSet.hpp:148 148 uint32 before = words()[word_index]; (gdb) bt #0 remove (this=0x7f8c89df95b0, a=<value optimized out>) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/indexSet.hpp:148 #1 remove (this=0x7f8c89df95b0, a=<value optimized out>) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/indexSet.hpp:308 #2 PhaseIFG::remove_node (this=0x7f8c89df95b0, a=<value optimized out>) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/ifg.cpp:151 #3 0x00007f8d0980a7fe in PhaseChaitin::Simplify (this=0x7f8c89dfacf0) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/chaitin.cpp:1171 #4 0x00007f8d0980e6f9 in PhaseChaitin::Register_Allocate (this=<value optimized out>) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/chaitin.cpp:502 #5 0x00007f8d09898bcf in Compile::Code_Gen (this=0x7f8c89dfbb80) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/compile.cpp:2373 #6 0x00007f8d0989b902 in Compile::Compile (this=0x7f8c89dfbb80, ci_env=<value optimized out>, compiler=0x7f8d04881050, target=<value optimized out>, osr_bci=<value optimized out>, subsume_loads=<value optimized out>, do_escape_analysis=true, eliminate_boxing=true) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/compile.cpp:910 #7 0x00007f8d097f38dc in C2Compiler::compile_method (this=0x7f8d04881050, env=0x7f8c89dfc660, target=0x7f8c6463c1b0, entry_bci=-1) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/c2compiler.cpp:118 #8 0x00007f8d098a40d6 in CompileBroker::invoke_compiler_on_method (task=0x7f8d05bf8410) ... In crashing thread: (gdb) frame 8 #8 idom_no_update (this=0x7f8c89efb410, n=0x7f8c711f5110) at /usr/src/debug/java-1.8.0-openjdk-1.8.0.121-0.b13.el6_8.x86_64/openjdk/hotspot/src/share/vm/opto/loopnode.hpp:732 732 while (n->in(0) == NULL) { // Skip dead CFG nodes (gdb) list 727 728 Node* idom_no_update(Node* d) const { 729 assert(d->_idx < _idom_size, "oob"); 730 Node* n = _idom[d->_idx]; 731 assert(n != NULL,"Bad immediate dominator info."); 732 while (n->in(0) == NULL) { // Skip dead CFG nodes 733 //n = n->in(1); 734 n = (Node*)(((intptr_t)_nodes[n->_idx]) & ~1); 735 assert(n != NULL,"Bad immediate dominator info."); 736 } (gdb) p _idom $1 = (Node **) 0x7f8c70745ac0 (gdb) p n $16 = (Node *) 0x0 (gdb) p d $2 = <value optimized out> << from disassembly, "d" is in $rbx >> (gdb) p *(Node*)$rbx $3 = {_vptr.Node = 0x7f8d0a2cf690, _in = 0x7f8c0000000e, _out = 0x7f8c89efcc00, _cnt = 76029872, _max = 32653, _outcnt = 76029872, _outmax = 32653, _idx = 16384, _class_id = 32653, _flags = 0, static NotAMachineReg = 4294901760} (gdb) p _idom[16384] $4 = (Node *) 0x7f8d0a321560 (gdb) p *_idom[16384] $5 = {_vptr.Node = 0x0, _in = 0x0, _out = 0x0, _cnt = 0, _max = 0, _outcnt = 1, _outmax = 7581, _idx = 104, _class_id = 0, _flags = 0, static NotAMachineReg = 4294901760}