During work on the 6353664 fix I found few places I wanted to fix
but it was late for mustang release.

Fixed Node::destruct() (broken after my 5082174 fix).
Fix typo (use class's field _igvn instead of input parameter igvn).
Let Value() calculate result for const1/const2, const1%const2 and const1*const2.
Don't generate ideal graph for unreachable path in inline_arraycopy().
Conver the method Node::verify_recur() to iterative version.
The recursion causes compiler stack overflow when run CTW with
-XX:+VerifyIterativeGVN on x86:

fez% /java/re/jdk/1.6.0/latest/binaries/solaris-i586/fastdebug/bin/java -server -XX:+PrintCompilation -XX:+VerifyIterativeGVN -XX:+CompileTheWorld -XX:CompileTheWorldStartAt=1 -Xbootclasspath/p:/net/vmsqe.sfbay/export/backup/testbase/CompileTheWorld/jarfiles/ClassInfoLib.jar
VM option '+PrintCompilation'
VM option '+VerifyIterativeGVN'
VM option '+CompileTheWorld'
VM option 'CompileTheWorldStartAt=1'
CompileTheWorld : Compiling all classes in /net/vmsqe.sfbay/export/backup/testbase/CompileTheWorld/jarfiles/ClassInfoLib.jar

CompileTheWorld (1) : com/sun/classinfo/ClassFileEntry
CompileTheWorld (2) : com/sun/classinfo/ClassPath
CompileTheWorld (3) : com/sun/classinfo/Path
CompileTheWorld (4) : com/sun/classinfo/PathFactory
  1 b com.sun.classinfo.PathFactory::<init> (5 bytes)
  2 b com.sun.classinfo.PathFactory::createClassFileEntry (7 bytes)
  3 b com.sun.classinfo.PathFactory::createClassPath (9 bytes)
  4 b com.sun.classinfo.PathFactory::createClassPath (10 bytes)
  5 b com.sun.classinfo.PathFactory::createClassPath (8 bytes)
  6 b com.sun.classinfo.PathFactory::createPath (5 bytes)
  7 b com.sun.classinfo.PathFactory::createWritePath (5 bytes)
  8 b com.sun.classinfo.PathFactory::isClassPath (5 bytes)
  9 b com.sun.classinfo.PathFactory::isPath (5 bytes)
 10 b com.sun.classinfo.PathFactory::isWriteablePath (5 bytes)
CompileTheWorld (5) : com/sun/classinfo/resources/ClassLibRes
 11 b com.sun.classinfo.resources.ClassLibRes::<init> (5 bytes)
 12 b com.sun.classinfo.resources.ClassLibRes::<clinit> (6406 bytes)
Segmentation Fault
Fix Set::setstr() to delete temporary 'set' only if it is allocated on C_HEAP.
Got the next assert with -XX:+TraceIterativeGVN :

#
# An unexpected error has been detected by Java Runtime Environment:
#
# Internal Error (/net/jaberwocky/export/home2/work/6353664/src/share/vm/memory/allocation.cpp, 44), pid=7999, tid=10
#
# Java VM: Java HotSpot(TM) Server VM (1.6.0-internal-debug mixed mode)
#
# Error: assert(((ResourceObj *)p)->allocated_on_C_heap(),"delete only allowed for C_HEAP objects")
# If you would like to submit a bug report, please visit:
# http://java.sun.com/webapps/bugreport/crash.jsp
#

--------------- T H R E A D ---------------

Current thread (0x081bb100): JavaThread "CompilerThread0" daemon [_thread_in_native, id=10]

Stack: [0xd6497000,0xd64d7000), sp=0xd64d52a8, free space=248k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x911d67] void VMError::report_and_die() + 0x577
V [libjvm.so+0x396749] void report_assertion_failure(const char*,int,const char*) + 0x79
V [libjvm.so+0x1f02c0] void ResourceObj::operator delete(void*) + 0x50
V [libjvm.so+0x948397] __SLIP.DELETER__B + 0x27
V [libjvm.so+0x8144e9] char*Set::setstr()const + 0x279
V [libjvm.so+0x814546] void Set::print()const + 0x16
V [libjvm.so+0x79f923] void Unique_Node_List::print_set()const + 0x23
V [libjvm.so+0x79c110] void PhaseIterGVN::optimize() + 0x100
V [libjvm.so+0x69cb98] PhaseIdealLoop::PhaseIdealLoop(PhaseIterGVN&,const PhaseIdealLoop*,bool) + 0x818
V [libjvm.so+0x3360c8] void Compile::Optimize() + 0x1d8
-----------

Add PinchPointNode to compute registers antidependances
and replace (n->Opcode() == Op_Node) with (n->is_PinchPoint())
when checking for pinch point nodes.

-----------
Move the creation of old_space, new_space and node_stack inside
iterative Node::verify_recur(). It speeds up the verification
by 20%.

-----------
Convert the method Node::find_recur() to iterative version.
--------------------------
Don't set HT bit for Opteron cpu. It was not fixed since 6290711 was closed.
------------
The usage of the flag VerifyGraphEdges since AllocateNode could set
InitialTest input to NULL. Have to fix it.

fez% /tmp/kvn/jdk1.6.0/fastdebug/bin/java -server -XX:+VerifyGraphEdges -Xcomp X
VM option '+VerifyGraphEdges'
# To suppress the following error report, specify this argument
# after -XX: or in .hotspotrc: SuppressErrorAt=/node.cpp:1259]
#
# An unexpected error has been detected by Java Runtime Environment:
#
# Internal Error (/export0/BUILD_AREA/jdk6.0/hotspot/src/share/vm/opto/node.cpp
, 1259), pid=23437, tid=10
#
# Java VM: Java HotSpot(TM) Server VM (1.6.0-ea-fastdebug-b58-debug compiled mod
e)
#
# Error: assert(i >= req() || i == 0 || is_Region() || is_Phi(),"only regions or
 phis have null data edges")
# An error report file with more information is saved as hs_err_pid23437.log
#
# If you would like to submit a bug report, please visit:
# http://java.sun.com/webapps/bugreport/crash.jsp
#
Current thread is 10
Dumping core ...
Abort
------------------------
Merge PhaseGVN::transform() and PhaseGVN::transform_no_reclaim() since
they have the same code.
------------
Fix code for the flag VerifyLoopOptimizations:

fez% /tmp/kvn/jdk1.6.0/fastdebug/bin/java -server -XX:+VerifyLoopOptimizations -Xcomp X
VM option '+VerifyLoopOptimizations'
Verify has that we do not: 742 If === 63 71 [[ 748 745 ]] P=0.999999,
C=-1.000000
Verify has that we do not: 745 IfFalse === 742 [[ 744 ]] #0
Verify has that we do not: 748 IfTrue === 742 [[ 747 ]] #1
Verify has that we do not: 743 If === 65 740 [[ 749 746 ]] P=0.999999,
 C=-1.000000
Verify has that we do not: 746 IfFalse === 743 [[ 744 ]] #0
Verify has that we do not: 749 IfTrue === 743 [[ 747 ]] #1
# To suppress the following error report, specify this argument
# after -XX: or in .hotspotrc: SuppressErrorAt=/loopnode.cpp:1647]
#
# An unexpected error has been detected by Java Runtime Environment:
#
# Internal Error (/export0/BUILD_AREA/jdk6.0/hotspot/src/share/vm/opto/loopnode.cpp, 1647), pid=8241, tid=11
#
# Java VM: Java HotSpot(TM) Server VM (1.6.0-ea-fastdebug-b58-debug compiled mode)
#
# Error: assert(!fail,"loop body mismatch")
# An error report file with more information is saved as hs_err_pid8241.log
#
# If you would like to submit a bug report, please visit:
# http://java.sun.com/webapps/bugreport/crash.jsp
#
Current thread is 11
Dumping core ...
Abort
fez%
---------------------------------------------
PhaseIdealLoop::split_through_phi() should respect anti-dependances
for Load node clones.
---------------------------------------
Iterative version of PhaseIdealLoop::verify_compare().
----------------------------
Convert the method Node::kill_dead_code() to iterative version.
The recursion causes compiler stack overflow when run CTW with
 -XX:+VerifyGraphEdges -XX:+VerifyIterativeGVN on x86:

/tmp/kvn/jdk1.6.0/bin/java -server -XX:+VerifyGraphEdges -XX:+VerifyIterativeGVN -Xss4m -verify -XX:-ShowMessageBoxOnError -XX:+CompileTheWorld -XX:CompileTheWorldStartAt=1 -Xbootclasspath/p:/net/vmsqe.sfbay/export/backup/testbase/CompileTheWorld/jarfiles/JavaWebServer1.1.3.jar
...
CompileTheWorld (965) : mlsoft/mct/MlEKey
CompileTheWorld (966) : mlsoft/mct/MlResource
CompileTheWorld (967) : mlsoft/mct/MlGrid
/tmp/kvn/test/workdir/run.JavaWebServer1.1.3.jar.1.ksh[67]: 15796 Segmentation Fault
Exit Value 139

[t@11 l@11]: where
current thread: t@11
  [1] Unique_Node_List::remove(this = ???, n = ???) (optimized), at 0xfe25cead (line ~1531) in "/net/jaberwocky/export/home2/work/6359849/src/share/vm/opto/node.cpp"
=>[2] kill_dead_code(dead = ???, igvn = ???) (optimized), at 0xfe259008 (line ~916) in "/net/jaberwocky/export/home2/work/6359849/src/share/vm/opto/node.cpp"
  [3] kill_dead_code(dead = ???, igvn = ???) (optimized), at 0xfe25955c (line ~946) in "/net/jaberwocky/export/home2/work/6359849/src/share/vm/opto/node.cpp"
  [4] kill_dead_code(dead = ???, igvn = ???) (optimized), at 0xfe25955c (line ~946) in "/net/jaberwocky/export/home2/work/6359849/src/share/vm/opto/node.cpp"
  [5] kill_dead_code(dead = ???, igvn = ???) (optimized), at 0xfe25955c (line ~946) in "/net/jaberwocky/export/home2/work/6359849/src/share/vm/opto/node.cpp"
-----------------------------------------------------------------
AddP node should be put to correspondent loop body when
we move it up in dominator tree in PhaseIdealLoop::has_local_phi_input().
--------------------------------------------------------------------------------
Relax anti-dependences checks for Load nodes in PhaseIdealLoop::get_late_ctrl().
For example, when uncommon trap is the user of the memory input.