[8u-dev] Request for approval: Backport of 8011858

[Zoltán Majó]

Hi Vlad,


On 09/15/2015 05:33 PM, Vlad Ureche wrote:
>
> On Tue, Sep 15, 2015 at 3:54 PM, Zoltán Majó <zoltan.majo at oracle.com 
> <mailto:zoltan.majo at oracle.com>> wrote:
>
>
>     1) in matcher.cpp on line 345 for determining the stack size used
>     in xform();
>     2) in compile.cpp on line 330 for the estimated worklist size.
>
>
> Zoltán, sorry for not catching those two cases on the original patch.

No problem at all! Thank you for sending your notes, they'll be useful 
to avoid looking at what you've already considered.

Best wishes,


Zoltan

> Here are the notes I took back then, although line numbers may have 
> shifted:
>
>   * hotspot/src/share/vm/opto/cfgnode.cpp:
>       o 805: Node_Stack   Node_Stack stack(a, C->unique() >> 4); => 
> *C->live_nodes() >> 4*
>   * hotspot/src/share/vm/opto/chaitin.cpp:
>       o 1795: Node **derived_base_map = 
> (Node**)a->Amalloc(sizeof(Node*)*C->unique()); => *needs all indices for
>         PhaseChaitin::find_base_for_derived*
>   * hotspot/src/share/vm/opto/compile.cpp:
>       o 320: int estimated_worklist_size = unique(); => *int 
> estimated_worklist_size = live_nodes();*
>       o 3314: Node_Stack nstack(unique() >> 1); => *Node_Stack 
> nstack(live_nodes() >> 1);*
>   * hotspot/src/share/vm/opto/domgraph.cpp:
>       o 393: *leave unique() alone, since the algorithms rely on indices*
>   * hotspot/src/share/vm/opto/escape.cpp:
>       o 41: _nodes(C->comp_arena(), C->unique(), C->unique(), NULL) => 
> *leave it alone, nodes are accessed by index*
>   * hotspot/src/share/vm/opto/gcm.cpp:
>       o 111: GrowableArray <Node *> spstack(C->unique() + 8); => 
> *GrowableArray <Node *> spstack(C->live_nodes() + 8);*
>       o 1313: stack.map((C->unique() >> 1) + 16, NULL); => 
> *stack.map((C->live_nodes() >> 1) + 16, NULL);*
>       o 1374: GrowableArray ready_cnt(C->unique(), C->unique(), -1); 
> => *leave it, it requires index-based access*
>   * hotspot/src/share/vm/opto/loopnode.cpp:
>       o 2128: _nodes.map(C->unique(), NULL); => *leave it, it requires 
> index-based access*
>       o 2203: _idom      = NEW_RESOURCE_ARRAY( Node*, _idom_size ); => 
> *leave it, it requires index-based access*
>       o 2234: int stack_size = (C->unique() >> 1) + 16; // 
> (unique>>1)+16 from Java2D stats => *int stack_size =
>         (C->live_nodes() >> 1) + 16*
>       o 2690: uint init_size = C->unique() / 100; => *uint init_size = 
> C->live_nodes() / 100;*
>       o 2781: GrowableArray <Node *> bltstack(C->unique() >> 1);**=> 
> *GrowableArray <Node *> bltstack(C->live_nodes() >> 1);*
>       o 3671: Node_Stack stack(arena, C->unique() >> 2)**=> 
> *Node_Stack stack(arena, C->live_nodes() >> 2);*
>   * hotspot/src/share/vm/opto/loopnode.hpp:
>       o 521: _max_preorder = C->unique()+8; => *I don't understand why 
> +8, since indexing occurs based on node indices :|*
>       o other occurences are similar
>   * hotspot/src/share/vm/opto/loopTransform.cpp:
>       o 1216: Node_Stack stack(arena, C->unique() >> 2); => 
> *Node_Stack stack(arena, C->live_nodes() >> 2);*
>   * hotspot/src/share/vm/opto/matcher.cpp:
>       o 326: grow_new_node_array(C->unique()); => *leave alone, 
> indexing based on nodes*
>       o 2053: MStack mstack(C->unique() * 2);=> *this can probably be 
> optimized as well, I guess*
>   * hotspot/src/share/vm/opto/node.cpp:
>       o 1771: GrowableArray <Node *> nstack(C->unique()); => 
> *GrowableArray <Node *> nstack(C->live_nodes());*
>   * hotspot/src/share/vm/opto/phaseX.cpp:
>       o 461,477: _types.map(C->unique(), NULL); => *leave alone, 
> index-based access occurs later*
>       o 794,811: _stack(C->unique() >> 1), => *_stack(C->live_nodes() 
> >> 1),*
>       o 1641: GrowableArray <Node *> trstack(C->unique() >> 1); => 
> *GrowableArray <Node *> trstack(C->live_nodes() >> 1);*
>
> Hope this is of use for you!
> Vlad