148
149 // Find and remove n from block list
150 void Block::find_remove( const Node *n ) {
151 _nodes.remove(find_node(n));
152 }
153
154 //------------------------------is_Empty---------------------------------------
155 // Return empty status of a block. Empty blocks contain only the head, other
156 // ideal nodes, and an optional trailing goto.
157 int Block::is_Empty() const {
158
159 // Root or start block is not considered empty
160 if (head()->is_Root() || head()->is_Start()) {
161 return not_empty;
162 }
163
164 int success_result = completely_empty;
165 int end_idx = _nodes.size()-1;
166
167 // Check for ending goto
168 if ((end_idx > 0) && (_nodes[end_idx]->is_Goto())) {
169 success_result = empty_with_goto;
170 end_idx--;
171 }
172
173 // Unreachable blocks are considered empty
174 if (num_preds() <= 1) {
175 return success_result;
176 }
177
178 // Ideal nodes are allowable in empty blocks: skip them Only MachNodes
179 // turn directly into code, because only MachNodes have non-trivial
180 // emit() functions.
181 while ((end_idx > 0) && !_nodes[end_idx]->is_Mach()) {
182 end_idx--;
183 }
184
185 // No room for any interesting instructions?
186 if (end_idx == 0) {
187 return success_result;
188 }
189
190 return not_empty;
191 }
192
193 //------------------------------has_uncommon_code------------------------------
194 // Return true if the block's code implies that it is likely to be
195 // executed infrequently. Check to see if the block ends in a Halt or
196 // a low probability call.
197 bool Block::has_uncommon_code() const {
198 Node* en = end();
199
200 if (en->is_Goto())
201 en = en->in(0);
202 if (en->is_Catch())
203 en = en->in(0);
204 if (en->is_Proj() && en->in(0)->is_MachCall()) {
205 MachCallNode* call = en->in(0)->as_MachCall();
206 if (call->cnt() != COUNT_UNKNOWN && call->cnt() <= PROB_UNLIKELY_MAG(4)) {
207 // This is true for slow-path stubs like new_{instance,array},
208 // slow_arraycopy, complete_monitor_locking, uncommon_trap.
209 // The magic number corresponds to the probability of an uncommon_trap,
210 // even though it is a count not a probability.
211 return true;
212 }
213 }
214
215 int op = en->is_Mach() ? en->as_Mach()->ideal_Opcode() : en->Opcode();
216 return op == Op_Halt;
217 }
218
219 //------------------------------is_uncommon------------------------------------
220 // True if block is low enough frequency or guarded by a test which
221 // mostly does not go here.
222 bool Block::is_uncommon( Block_Array &bbs ) const {
223 // Initial blocks must never be moved, so are never uncommon.
224 if (head()->is_Root() || head()->is_Start()) return false;
928 is_loop = true;
929 break; // Some kind of loop
930 }
931 }
932 }
933 assert( is_loop || b->find_node(def) < j, "uses must follow definitions" );
934 }
935 if( def->is_SafePointScalarObject() ) {
936 assert(_bbs[def->_idx] == b, "SafePointScalarObject Node should be at the same block as its SafePoint node");
937 assert(_bbs[def->_idx] == _bbs[def->in(0)->_idx], "SafePointScalarObject Node should be at the same block as its control edge");
938 }
939 }
940 }
941 }
942
943 j = b->end_idx();
944 Node *bp = (Node*)b->_nodes[b->_nodes.size()-1]->is_block_proj();
945 assert( bp, "last instruction must be a block proj" );
946 assert( bp == b->_nodes[j], "wrong number of successors for this block" );
947 if( bp->is_Catch() ) {
948 while( b->_nodes[--j]->Opcode() == Op_MachProj ) ;
949 assert( b->_nodes[j]->is_Call(), "CatchProj must follow call" );
950 }
951 else if( bp->is_Mach() && bp->as_Mach()->ideal_Opcode() == Op_If ) {
952 assert( b->_num_succs == 2, "Conditional branch must have two targets");
953 }
954 }
955 #endif
956 }
957 #endif
958
959 //=============================================================================
960 //------------------------------UnionFind--------------------------------------
961 UnionFind::UnionFind( uint max ) : _cnt(max), _max(max), _indices(NEW_RESOURCE_ARRAY(uint,max)) {
962 Copy::zero_to_bytes( _indices, sizeof(uint)*max );
963 }
964
965 void UnionFind::extend( uint from_idx, uint to_idx ) {
966 _nesting.check();
967 if( from_idx >= _max ) {
968 uint size = 16;
969 while( size <= from_idx ) size <<=1;
|
148
149 // Find and remove n from block list
150 void Block::find_remove( const Node *n ) {
151 _nodes.remove(find_node(n));
152 }
153
154 //------------------------------is_Empty---------------------------------------
155 // Return empty status of a block. Empty blocks contain only the head, other
156 // ideal nodes, and an optional trailing goto.
157 int Block::is_Empty() const {
158
159 // Root or start block is not considered empty
160 if (head()->is_Root() || head()->is_Start()) {
161 return not_empty;
162 }
163
164 int success_result = completely_empty;
165 int end_idx = _nodes.size()-1;
166
167 // Check for ending goto
168 if ((end_idx > 0) && (_nodes[end_idx]->is_MachGoto())) {
169 success_result = empty_with_goto;
170 end_idx--;
171 }
172
173 // Unreachable blocks are considered empty
174 if (num_preds() <= 1) {
175 return success_result;
176 }
177
178 // Ideal nodes are allowable in empty blocks: skip them Only MachNodes
179 // turn directly into code, because only MachNodes have non-trivial
180 // emit() functions.
181 while ((end_idx > 0) && !_nodes[end_idx]->is_Mach()) {
182 end_idx--;
183 }
184
185 // No room for any interesting instructions?
186 if (end_idx == 0) {
187 return success_result;
188 }
189
190 return not_empty;
191 }
192
193 //------------------------------has_uncommon_code------------------------------
194 // Return true if the block's code implies that it is likely to be
195 // executed infrequently. Check to see if the block ends in a Halt or
196 // a low probability call.
197 bool Block::has_uncommon_code() const {
198 Node* en = end();
199
200 if (en->is_MachGoto())
201 en = en->in(0);
202 if (en->is_Catch())
203 en = en->in(0);
204 if (en->is_MachProj() && en->in(0)->is_MachCall()) {
205 MachCallNode* call = en->in(0)->as_MachCall();
206 if (call->cnt() != COUNT_UNKNOWN && call->cnt() <= PROB_UNLIKELY_MAG(4)) {
207 // This is true for slow-path stubs like new_{instance,array},
208 // slow_arraycopy, complete_monitor_locking, uncommon_trap.
209 // The magic number corresponds to the probability of an uncommon_trap,
210 // even though it is a count not a probability.
211 return true;
212 }
213 }
214
215 int op = en->is_Mach() ? en->as_Mach()->ideal_Opcode() : en->Opcode();
216 return op == Op_Halt;
217 }
218
219 //------------------------------is_uncommon------------------------------------
220 // True if block is low enough frequency or guarded by a test which
221 // mostly does not go here.
222 bool Block::is_uncommon( Block_Array &bbs ) const {
223 // Initial blocks must never be moved, so are never uncommon.
224 if (head()->is_Root() || head()->is_Start()) return false;
928 is_loop = true;
929 break; // Some kind of loop
930 }
931 }
932 }
933 assert( is_loop || b->find_node(def) < j, "uses must follow definitions" );
934 }
935 if( def->is_SafePointScalarObject() ) {
936 assert(_bbs[def->_idx] == b, "SafePointScalarObject Node should be at the same block as its SafePoint node");
937 assert(_bbs[def->_idx] == _bbs[def->in(0)->_idx], "SafePointScalarObject Node should be at the same block as its control edge");
938 }
939 }
940 }
941 }
942
943 j = b->end_idx();
944 Node *bp = (Node*)b->_nodes[b->_nodes.size()-1]->is_block_proj();
945 assert( bp, "last instruction must be a block proj" );
946 assert( bp == b->_nodes[j], "wrong number of successors for this block" );
947 if( bp->is_Catch() ) {
948 while( b->_nodes[--j]->is_MachProj() ) ;
949 assert( b->_nodes[j]->is_MachCall(), "CatchProj must follow call" );
950 }
951 else if( bp->is_Mach() && bp->as_Mach()->ideal_Opcode() == Op_If ) {
952 assert( b->_num_succs == 2, "Conditional branch must have two targets");
953 }
954 }
955 #endif
956 }
957 #endif
958
959 //=============================================================================
960 //------------------------------UnionFind--------------------------------------
961 UnionFind::UnionFind( uint max ) : _cnt(max), _max(max), _indices(NEW_RESOURCE_ARRAY(uint,max)) {
962 Copy::zero_to_bytes( _indices, sizeof(uint)*max );
963 }
964
965 void UnionFind::extend( uint from_idx, uint to_idx ) {
966 _nesting.check();
967 if( from_idx >= _max ) {
968 uint size = 16;
969 while( size <= from_idx ) size <<=1;
|