1190 // phi / --
1191
1192 Node* r = in(0); // RegionNode
1193 if (r == NULL) return in(1); // Already degraded to a Copy
1194 Node* input = NULL; // The unique direct input (maybe uncasted = ConstraintCasts removed)
1195
1196 for (uint i = 1, cnt = req(); i < cnt; ++i) {
1197 Node* rc = r->in(i);
1198 if (rc == NULL || phase->type(rc) == Type::TOP)
1199 continue; // ignore unreachable control path
1200 Node* n = in(i);
1201 if (n == NULL)
1202 continue;
1203 Node* un = n;
1204 if (uncast) {
1205 #ifdef ASSERT
1206 Node* m = un->uncast();
1207 #endif
1208 while (un != NULL && un->req() == 2 && un->is_ConstraintCast()) {
1209 Node* next = un->in(1);
1210 if (phase->type(next)->isa_rawptr() && phase->type(un)->isa_oopptr()) {
1211 // risk exposing raw ptr at safepoint
1212 break;
1213 }
1214 un = next;
1215 }
1216 assert(m == un || un->in(1) == m, "Only expected at CheckCastPP from allocation");
1217 }
1218 if (un == NULL || un == this || phase->type(un) == Type::TOP) {
1219 continue; // ignore if top, or in(i) and "this" are in a data cycle
1220 }
1221 // Check for a unique input (maybe uncasted)
1222 if (input == NULL) {
1223 input = un;
1224 } else if (input != un) {
1225 input = NodeSentinel; // no unique input
1226 }
1227 }
1228 if (input == NULL) {
1229 return phase->C->top(); // no inputs
1230 }
1231
1232 if (input != NodeSentinel) {
1233 return input; // one unique direct input
1234 }
1235
1236 // Nothing.
|
1190 // phi / --
1191
1192 Node* r = in(0); // RegionNode
1193 if (r == NULL) return in(1); // Already degraded to a Copy
1194 Node* input = NULL; // The unique direct input (maybe uncasted = ConstraintCasts removed)
1195
1196 for (uint i = 1, cnt = req(); i < cnt; ++i) {
1197 Node* rc = r->in(i);
1198 if (rc == NULL || phase->type(rc) == Type::TOP)
1199 continue; // ignore unreachable control path
1200 Node* n = in(i);
1201 if (n == NULL)
1202 continue;
1203 Node* un = n;
1204 if (uncast) {
1205 #ifdef ASSERT
1206 Node* m = un->uncast();
1207 #endif
1208 while (un != NULL && un->req() == 2 && un->is_ConstraintCast()) {
1209 Node* next = un->in(1);
1210 // Make sure we don't lose type information
1211 if (!phase->type(next)->higher_equal(phase->type(un))) {
1212 break;
1213 }
1214 un = next;
1215 }
1216 }
1217 if (un == NULL || un == this || phase->type(un) == Type::TOP) {
1218 continue; // ignore if top, or in(i) and "this" are in a data cycle
1219 }
1220 // Check for a unique input (maybe uncasted)
1221 if (input == NULL) {
1222 input = un;
1223 } else if (input != un) {
1224 input = NodeSentinel; // no unique input
1225 }
1226 }
1227 if (input == NULL) {
1228 return phase->C->top(); // no inputs
1229 }
1230
1231 if (input != NodeSentinel) {
1232 return input; // one unique direct input
1233 }
1234
1235 // Nothing.
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