1.1 --- a/src/share/vm/opto/node.cpp Tue May 05 18:39:57 2020 +0100
1.2 +++ b/src/share/vm/opto/node.cpp Tue Mar 10 10:46:35 2020 +0100
1.3 @@ -1,5 +1,5 @@
1.4 /*
1.5 - * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
1.6 + * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
1.7 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.8 *
1.9 * This code is free software; you can redistribute it and/or modify it
1.10 @@ -818,8 +818,9 @@
1.11 // First remove corresponding def-use edge
1.12 Node *n = in(idx);
1.13 if (n != NULL) n->del_out((Node *)this);
1.14 - _in[idx] = in(--_cnt); // Compact the array
1.15 - _in[_cnt] = NULL; // NULL out emptied slot
1.16 + _in[idx] = in(--_cnt); // Compact the array
1.17 + // Avoid spec violation: Gap in prec edges.
1.18 + close_prec_gap_at(_cnt);
1.19 }
1.20
1.21 //------------------------------del_req_ordered--------------------------------
1.22 @@ -831,10 +832,11 @@
1.23 // First remove corresponding def-use edge
1.24 Node *n = in(idx);
1.25 if (n != NULL) n->del_out((Node *)this);
1.26 - if (idx < _cnt - 1) { // Not last edge ?
1.27 - Copy::conjoint_words_to_lower((HeapWord*)&_in[idx+1], (HeapWord*)&_in[idx], ((_cnt-idx-1)*sizeof(Node*)));
1.28 + if (idx < --_cnt) { // Not last edge ?
1.29 + Copy::conjoint_words_to_lower((HeapWord*)&_in[idx+1], (HeapWord*)&_in[idx], ((_cnt-idx)*sizeof(Node*)));
1.30 }
1.31 - _in[--_cnt] = NULL; // NULL out emptied slot
1.32 + // Avoid spec violation: Gap in prec edges.
1.33 + close_prec_gap_at(_cnt);
1.34 }
1.35
1.36 //------------------------------ins_req----------------------------------------
1.37 @@ -865,10 +867,12 @@
1.38 uint nrep = 0;
1.39 for (uint i = 0; i < len(); i++) {
1.40 if (in(i) == old) {
1.41 - if (i < req())
1.42 + if (i < req()) {
1.43 set_req(i, neww);
1.44 - else
1.45 + } else {
1.46 + assert(find_prec_edge(neww) == -1, err_msg("spec violation: duplicated prec edge (node %d -> %d)", _idx, neww->_idx));
1.47 set_prec(i, neww);
1.48 + }
1.49 nrep++;
1.50 }
1.51 }
1.52 @@ -974,24 +978,27 @@
1.53
1.54 // Find a precedence edge to move
1.55 uint i = _cnt;
1.56 - while( in(i) != NULL ) i++;
1.57 + while( in(i) != NULL ) {
1.58 + if (in(i) == n) return; // Avoid spec violation: duplicated prec edge.
1.59 + i++;
1.60 + }
1.61 _in[i] = n; // Stuff prec edge over NULL
1.62 if ( n != NULL) n->add_out((Node *)this); // Add mirror edge
1.63 +
1.64 +#ifdef ASSERT
1.65 + while ((++i)<_max) { assert(_in[i] == NULL, err_msg("spec violation: Gap in prec edges (node %d)", _idx)); }
1.66 +#endif
1.67 }
1.68
1.69 //------------------------------rm_prec----------------------------------------
1.70 // Remove a precedence input. Precedence inputs are unordered, with
1.71 // duplicates removed and NULLs packed down at the end.
1.72 void Node::rm_prec( uint j ) {
1.73 -
1.74 - // Find end of precedence list to pack NULLs
1.75 - uint i;
1.76 - for( i=j; i<_max; i++ )
1.77 - if( !_in[i] ) // Find the NULL at end of prec edge list
1.78 - break;
1.79 - if (_in[j] != NULL) _in[j]->del_out((Node *)this);
1.80 - _in[j] = _in[--i]; // Move last element over removed guy
1.81 - _in[i] = NULL; // NULL out last element
1.82 + assert(j < _max, err_msg("oob: i=%d, _max=%d", j, _max));
1.83 + assert(j >= _cnt, "not a precedence edge");
1.84 + if (_in[j] == NULL) return; // Avoid spec violation: Gap in prec edges.
1.85 + _in[j]->del_out((Node *)this);
1.86 + close_prec_gap_at(j);
1.87 }
1.88
1.89 //------------------------------size_of----------------------------------------
