Mercurial > hg > truffle
changeset 305:ab075d07f1ba
6736417: Fastdebug C2 crashes in StoreBNode::Ideal
Summary: The result of step_through_mergemem() and remove_dead_region() is not checked in some cases.
Reviewed-by: never
author | kvn |
---|---|
date | Wed, 27 Aug 2008 09:15:46 -0700 |
parents | dc7f315e41f7 |
children | af945ba2e739 |
files | src/share/vm/opto/callnode.cpp src/share/vm/opto/connode.cpp src/share/vm/opto/divnode.cpp src/share/vm/opto/memnode.cpp src/share/vm/opto/node.cpp src/share/vm/opto/phaseX.cpp |
diffstat | 6 files changed, 32 insertions(+), 13 deletions(-) [+] |
line wrap: on
line diff
--- a/src/share/vm/opto/callnode.cpp Wed Aug 27 00:21:55 2008 -0700 +++ b/src/share/vm/opto/callnode.cpp Wed Aug 27 09:15:46 2008 -0700 @@ -829,9 +829,7 @@ //------------------------------Ideal------------------------------------------ // Skip over any collapsed Regions Node *SafePointNode::Ideal(PhaseGVN *phase, bool can_reshape) { - if (remove_dead_region(phase, can_reshape)) return this; - - return NULL; + return remove_dead_region(phase, can_reshape) ? this : NULL; } //------------------------------Identity---------------------------------------
--- a/src/share/vm/opto/connode.cpp Wed Aug 27 00:21:55 2008 -0700 +++ b/src/share/vm/opto/connode.cpp Wed Aug 27 09:15:46 2008 -0700 @@ -101,6 +101,8 @@ // Move constants to the right. Node *CMoveNode::Ideal(PhaseGVN *phase, bool can_reshape) { if( in(0) && remove_dead_region(phase, can_reshape) ) return this; + // Don't bother trying to transform a dead node + if( in(0) && in(0)->is_top() ) return NULL; assert( !phase->eqv(in(Condition), this) && !phase->eqv(in(IfFalse), this) && !phase->eqv(in(IfTrue), this), "dead loop in CMoveNode::Ideal" );
--- a/src/share/vm/opto/divnode.cpp Wed Aug 27 00:21:55 2008 -0700 +++ b/src/share/vm/opto/divnode.cpp Wed Aug 27 09:15:46 2008 -0700 @@ -402,6 +402,8 @@ // Divides can be changed to multiplies and/or shifts Node *DivINode::Ideal(PhaseGVN *phase, bool can_reshape) { if (in(0) && remove_dead_region(phase, can_reshape)) return this; + // Don't bother trying to transform a dead node + if( in(0) && in(0)->is_top() ) return NULL; const Type *t = phase->type( in(2) ); if( t == TypeInt::ONE ) // Identity? @@ -499,6 +501,8 @@ // Dividing by a power of 2 is a shift. Node *DivLNode::Ideal( PhaseGVN *phase, bool can_reshape) { if (in(0) && remove_dead_region(phase, can_reshape)) return this; + // Don't bother trying to transform a dead node + if( in(0) && in(0)->is_top() ) return NULL; const Type *t = phase->type( in(2) ); if( t == TypeLong::ONE ) // Identity? @@ -640,6 +644,8 @@ //------------------------------Idealize--------------------------------------- Node *DivFNode::Ideal(PhaseGVN *phase, bool can_reshape) { if (in(0) && remove_dead_region(phase, can_reshape)) return this; + // Don't bother trying to transform a dead node + if( in(0) && in(0)->is_top() ) return NULL; const Type *t2 = phase->type( in(2) ); if( t2 == TypeF::ONE ) // Identity? @@ -725,6 +731,8 @@ //------------------------------Idealize--------------------------------------- Node *DivDNode::Ideal(PhaseGVN *phase, bool can_reshape) { if (in(0) && remove_dead_region(phase, can_reshape)) return this; + // Don't bother trying to transform a dead node + if( in(0) && in(0)->is_top() ) return NULL; const Type *t2 = phase->type( in(2) ); if( t2 == TypeD::ONE ) // Identity? @@ -760,7 +768,9 @@ //------------------------------Idealize--------------------------------------- Node *ModINode::Ideal(PhaseGVN *phase, bool can_reshape) { // Check for dead control input - if( remove_dead_region(phase, can_reshape) ) return this; + if( in(0) && remove_dead_region(phase, can_reshape) ) return this; + // Don't bother trying to transform a dead node + if( in(0) && in(0)->is_top() ) return NULL; // Get the modulus const Type *t = phase->type( in(2) ); @@ -929,7 +939,9 @@ //------------------------------Idealize--------------------------------------- Node *ModLNode::Ideal(PhaseGVN *phase, bool can_reshape) { // Check for dead control input - if( remove_dead_region(phase, can_reshape) ) return this; + if( in(0) && remove_dead_region(phase, can_reshape) ) return this; + // Don't bother trying to transform a dead node + if( in(0) && in(0)->is_top() ) return NULL; // Get the modulus const Type *t = phase->type( in(2) );
--- a/src/share/vm/opto/memnode.cpp Wed Aug 27 00:21:55 2008 -0700 +++ b/src/share/vm/opto/memnode.cpp Wed Aug 27 09:15:46 2008 -0700 @@ -214,6 +214,9 @@ Node *ctl = in(MemNode::Control); if (ctl && remove_dead_region(phase, can_reshape)) return this; + ctl = in(MemNode::Control); + // Don't bother trying to transform a dead node + if( ctl && ctl->is_top() ) return NodeSentinel; // Ignore if memory is dead, or self-loop Node *mem = in(MemNode::Memory); @@ -244,6 +247,7 @@ if (mem != old_mem) { set_req(MemNode::Memory, mem); + if (phase->type( mem ) == Type::TOP) return NodeSentinel; return this; } @@ -1316,6 +1320,7 @@ Node* opt_mem = MemNode::optimize_memory_chain(mem, addr_t, phase); if (opt_mem != mem) { set_req(MemNode::Memory, opt_mem); + if (phase->type( opt_mem ) == Type::TOP) return NULL; return this; } const TypeOopPtr *t_oop = addr_t->isa_oopptr(); @@ -2447,8 +2452,7 @@ // Return a node which is more "ideal" than the current node. Strip out // control copies Node *MemBarNode::Ideal(PhaseGVN *phase, bool can_reshape) { - if (remove_dead_region(phase, can_reshape)) return this; - return NULL; + return remove_dead_region(phase, can_reshape) ? this : NULL; } //------------------------------Value------------------------------------------
--- a/src/share/vm/opto/node.cpp Wed Aug 27 00:21:55 2008 -0700 +++ b/src/share/vm/opto/node.cpp Wed Aug 27 09:15:46 2008 -0700 @@ -1166,16 +1166,15 @@ // using it dead as well. This will happen normally via the usual IterGVN // worklist but this call is more efficient. Do not update use-def info // inside the dead region, just at the borders. -static bool kill_dead_code( Node *dead, PhaseIterGVN *igvn ) { +static void kill_dead_code( Node *dead, PhaseIterGVN *igvn ) { // Con's are a popular node to re-hit in the hash table again. - if( dead->is_Con() ) return false; + if( dead->is_Con() ) return; // Can't put ResourceMark here since igvn->_worklist uses the same arena // for verify pass with +VerifyOpto and we add/remove elements in it here. Node_List nstack(Thread::current()->resource_area()); Node *top = igvn->C->top(); - bool progress = false; nstack.push(dead); while (nstack.size() > 0) { @@ -1214,7 +1213,6 @@ for (uint i=0; i < dead->req(); i++) { Node *n = dead->in(i); // Get input to dead guy if (n != NULL && !n->is_top()) { // Input is valid? - progress = true; dead->set_req(i, top); // Smash input away if (n->outcnt() == 0) { // Input also goes dead? if (!n->is_Con()) @@ -1233,7 +1231,7 @@ } } // (dead->outcnt() == 0) } // while (nstack.size() > 0) for outputs - return progress; + return; } //------------------------------remove_dead_region----------------------------- @@ -1243,7 +1241,8 @@ // Lost control into this guy? I.e., it became unreachable? // Aggressively kill all unreachable code. if (can_reshape && n->is_top()) { - return kill_dead_code(this, phase->is_IterGVN()); + kill_dead_code(this, phase->is_IterGVN()); + return false; // Node is dead. } if( n->is_Region() && n->as_Region()->is_copy() ) {
--- a/src/share/vm/opto/phaseX.cpp Wed Aug 27 00:21:55 2008 -0700 +++ b/src/share/vm/opto/phaseX.cpp Wed Aug 27 09:15:46 2008 -0700 @@ -986,7 +986,9 @@ // Apply the Ideal call in a loop until it no longer applies Node *k = n; DEBUG_ONLY(dead_loop_check(k);) + DEBUG_ONLY(bool is_new = (k->outcnt() == 0);) Node *i = k->Ideal(this, /*can_reshape=*/true); + assert(i != k || is_new || i->outcnt() > 0, "don't return dead nodes"); #ifndef PRODUCT if( VerifyIterativeGVN ) verify_step(k); @@ -1024,7 +1026,9 @@ } DEBUG_ONLY(dead_loop_check(k);) // Try idealizing again + DEBUG_ONLY(is_new = (k->outcnt() == 0);) i = k->Ideal(this, /*can_reshape=*/true); + assert(i != k || is_new || i->outcnt() > 0, "don't return dead nodes"); #ifndef PRODUCT if( VerifyIterativeGVN ) verify_step(k);