src/gallium/drivers/nv50/codegen/nv50_ir_bb.cpp

   1 /*
   2  * Copyright 2011 Christoph Bumiller
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  17  * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  18  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
  19  * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  20  * SOFTWARE.
  21  */
  22
  23 #include "nv50_ir.h"
  24
  25 namespace nv50_ir {
  26
  27 Function::Function(Program *p, const char *fnName)
  28    : call(this),
  29      name(fnName),
  30      prog(p)
  31 {
  32    cfgExit = NULL;
  33    domTree = NULL;
  34
  35    bbArray = NULL;
  36    bbCount = 0;
  37    loopNestingBound = 0;
  38    regClobberMax = 0;
  39
  40    binPos = 0;
  41    binSize = 0;
  42
  43    prog->add(this, id);
  44 }
  45
  46 Function::~Function()
  47 {
  48    if (domTree)
  49       delete domTree;
  50    if (bbArray)
  51       delete[] bbArray;
  52
  53    for (ArrayList::Iterator BBs = allBBlocks.iterator(); !BBs.end(); BBs.next())
  54       delete reinterpret_cast<BasicBlock *>(BBs.get());
  55 }
  56
  57 BasicBlock::BasicBlock(Function *fn) : cfg(this), dom(this), func(fn)
  58 {
  59    program = func->getProgram();
  60
  61    joinAt = phi = entry = exit = NULL;
  62
  63    numInsns = 0;
  64    binPos = 0;
  65    binSize = 0;
  66
  67    explicitCont = false;
  68
  69    func->add(this, this->id);
  70 }
  71
  72 BasicBlock::~BasicBlock()
  73 {
  74    // nothing yet
  75 }
  76
  77 BasicBlock *
  78 BasicBlock::idom() const
  79 {
  80    Graph::Node *dn = dom.parent();
  81    return dn ? BasicBlock::get(dn) : NULL;
  82 }
  83
  84 void
  85 BasicBlock::insertHead(Instruction *inst)
  86 {
  87    assert(inst->next == 0 && inst->prev == 0);
  88
  89    if (inst->op == OP_PHI) {
  90       if (phi) {
  91          insertBefore(phi, inst);
  92       } else {
  93          if (entry) {
  94             insertBefore(entry, phi);
  95          } else {
  96             assert(!exit);
  97             phi = exit = inst;
  98             inst->bb = this;
  99             ++numInsns;
 100          }
 101       }
 102    } else {
 103       if (entry) {
 104          insertBefore(entry, inst);
 105       } else {
 106          if (phi) {
 107             insertAfter(phi, inst);
 108          } else {
 109             assert(!exit);
 110             entry = exit = inst;
 111             inst->bb = this;
 112             ++numInsns;
 113          }
 114       }
 115    }
 116 }
 117
 118 void
 119 BasicBlock::insertTail(Instruction *inst)
 120 {
 121    assert(inst->next == 0 && inst->prev == 0);
 122
 123    if (inst->op == OP_PHI) {
 124       if (entry) {
 125          insertBefore(entry, inst);
 126       } else
 127       if (exit) {
 128          assert(phi);
 129          insertAfter(exit, inst);
 130       } else {
 131          assert(!phi);
 132          phi = exit = inst;
 133          inst->bb = this;
 134          ++numInsns;
 135       }
 136    } else {
 137       if (exit) {
 138          insertAfter(exit, inst);
 139       } else {
 140          assert(!phi);
 141          entry = exit = inst;
 142          inst->bb = this;
 143          ++numInsns;
 144       }
 145    }
 146 }
 147
 148 void
 149 BasicBlock::insertBefore(Instruction *q, Instruction *p)
 150 {
 151    assert(p && q);
 152
 153    assert(p->next == 0 && p->prev == 0);
 154
 155    if (q == entry) {
 156       if (p->op == OP_PHI) {
 157          if (!phi)
 158             phi = p;
 159       } else {
 160          entry = p;
 161       }
 162    } else
 163    if (q == phi) {
 164       assert(p->op == OP_PHI);
 165       phi = p;
 166    }
 167
 168    p->next = q;
 169    p->prev = q->prev;
 170    if (p->prev)
 171       p->prev->next = p;
 172    q->prev = p;
 173
 174    p->bb = this;
 175    ++numInsns;
 176 }
 177
 178 void
 179 BasicBlock::insertAfter(Instruction *p, Instruction *q)
 180 {
 181    assert(p && q);
 182    assert(q->op != OP_PHI || p->op == OP_PHI);
 183
 184    assert(q->next == 0 && q->prev == 0);
 185
 186    if (p == exit)
 187       exit = q;
 188    if (p->op == OP_PHI && q->op != OP_PHI)
 189       entry = q;
 190
 191    q->prev = p;
 192    q->next = p->next;
 193    if (q->next)
 194       q->next->prev = q;
 195    p->next = q;
 196
 197    q->bb = this;
 198    ++numInsns;
 199 }
 200
 201 void
 202 BasicBlock::remove(Instruction *insn)
 203 {
 204    assert(insn->bb == this);
 205
 206    if (insn->prev)
 207       insn->prev->next = insn->next;
 208
 209    if (insn->next)
 210       insn->next->prev = insn->prev;
 211    else
 212       exit = insn->prev;
 213
 214    if (insn == entry)
 215       entry = insn->next ? insn->next : insn->prev;
 216
 217    if (insn == phi)
 218       phi = (insn->next && insn->next->op == OP_PHI) ? insn->next : 0;
 219
 220    --numInsns;
 221    insn->bb = NULL;
 222    insn->next =
 223    insn->prev = NULL;
 224 }
 225
 226 void BasicBlock::permuteAdjacent(Instruction *a, Instruction *b)
 227 {
 228    assert(a->bb == b->bb);
 229
 230    if (a->next != b) {
 231       Instruction *i = a;
 232       a = b;
 233       b = i;
 234    }
 235    assert(a->next == b);
 236    assert(a->op != OP_PHI && b->op != OP_PHI);
 237
 238    if (b == exit)
 239       exit = a;
 240    if (a == entry)
 241       entry = b;
 242
 243    b->prev = a->prev;
 244    a->next = b->next;
 245    b->next = a;
 246    a->prev = b;
 247
 248    if (b->prev)
 249       b->prev->next = b;
 250    if (a->prev)
 251       a->next->prev = a;
 252 }
 253
 254 bool
 255 BasicBlock::dominatedBy(BasicBlock *that)
 256 {
 257    Graph::Node *bn = &that->dom;
 258    Graph::Node *dn = &this->dom;
 259
 260    while (dn && dn != bn)
 261       dn = dn->parent();
 262
 263    return dn != NULL;
 264 }
 265
 266 unsigned int
 267 BasicBlock::initiatesSimpleConditional() const
 268 {
 269    Graph::Node *out[2];
 270    int n;
 271    Graph::Edge::Type eR;
 272
 273    if (cfg.outgoingCount() != 2) // -> if and -> else/endif
 274       return false;
 275
 276    n = 0;
 277    for (Graph::EdgeIterator ei = cfg.outgoing(); !ei.end(); ei.next())
 278       out[n++] = ei.getNode();
 279    eR = out[1]->outgoing().getType();
 280
 281    // IF block is out edge to the right
 282    if (eR == Graph::Edge::CROSS || eR == Graph::Edge::BACK)
 283       return 0x2;
 284
 285    if (out[1]->outgoingCount() != 1) // 0 is IF { RET; }, >1 is more divergence
 286       return 0x0;
 287    // do they reconverge immediately ?
 288    if (out[1]->outgoing().getNode() == out[0])
 289       return 0x1;
 290    if (out[0]->outgoingCount() == 1)
 291       if (out[0]->outgoing().getNode() == out[1]->outgoing().getNode())
 292          return 0x3;
 293
 294    return 0x0;
 295 }
 296
 297 bool
 298 Function::setEntry(BasicBlock *bb)
 299 {
 300    if (cfg.getRoot())
 301       return false;
 302    cfg.insert(&bb->cfg);
 303    return true;
 304 }
 305
 306 bool
 307 Function::setExit(BasicBlock *bb)
 308 {
 309    if (cfgExit)
 310       return false;
 311    cfgExit = &bb->cfg;
 312    return true;
 313 }
 314
 315 unsigned int
 316 Function::orderInstructions(ArrayList &result)
 317 {
 318    Iterator *iter;
 319    for (iter = cfg.iteratorCFG(); !iter->end(); iter->next())
 320       for (Instruction *insn = BasicBlock::get(*iter)->getFirst();
 321            insn; insn = insn->next)
 322          result.insert(insn, insn->serial);
 323    cfg.putIterator(iter);
 324    return result.getSize();
 325 }
 326
 327 bool
 328 Pass::run(Program *prog, bool ordered, bool skipPhi)
 329 {
 330    this->prog = prog;
 331    err = false;
 332    return doRun(prog, ordered, skipPhi);
 333 }
 334
 335 bool
 336 Pass::doRun(Program *prog, bool ordered, bool skipPhi)
 337 {
 338    for (ArrayList::Iterator fi = prog->allFuncs.iterator();
 339         !fi.end(); fi.next()) {
 340       Function *fn = reinterpret_cast<Function *>(fi.get());
 341       if (!doRun(fn, ordered, skipPhi))
 342          return false;
 343    }
 344    return !err;
 345 }
 346
 347 bool
 348 Pass::run(Function *func, bool ordered, bool skipPhi)
 349 {
 350    prog = func->getProgram();
 351    err = false;
 352    return doRun(func, ordered, skipPhi);
 353 }
 354
 355 bool
 356 Pass::doRun(Function *func, bool ordered, bool skipPhi)
 357 {
 358    Iterator *bbIter;
 359    BasicBlock *bb;
 360    Instruction *insn, *next;
 361
 362    this->func = func;
 363    if (!visit(func))
 364       return false;
 365
 366    bbIter = ordered ? func->cfg.iteratorCFG() : func->cfg.iteratorDFS();
 367
 368    for (; !bbIter->end(); bbIter->next()) {
 369       bb = BasicBlock::get(reinterpret_cast<Graph::Node *>(bbIter->get()));
 370       if (!visit(bb))
 371          break;
 372       for (insn = skipPhi ? bb->getEntry() : bb->getFirst(); insn != NULL;
 373            insn = next) {
 374          next = insn->next;
 375          if (!visit(insn))
 376             break;
 377       }
 378    }
 379    func->cfg.putIterator(bbIter);
 380    return !err;
 381 }
 382
 383 void
 384 Function::printCFGraph(const char *filePath)
 385 {
 386    FILE *out = fopen(filePath, "a");
 387    if (!out) {
 388       ERROR("failed to open file: %s\n", filePath);
 389       return;
 390    }
 391    INFO("printing control flow graph to: %s\n", filePath);
 392
 393    fprintf(out, "digraph G {\n");
 394
 395    Iterator *iter;
 396    for (iter = cfg.iteratorDFS(); !iter->end(); iter->next()) {
 397       BasicBlock *bb = BasicBlock::get(
 398          reinterpret_cast<Graph::Node *>(iter->get()));
 399       int idA = bb->getId();
 400       for (Graph::EdgeIterator ei = bb->cfg.outgoing(); !ei.end(); ei.next()) {
 401          int idB = BasicBlock::get(ei.getNode())->getId();
 402          switch (ei.getType()) {
 403          case Graph::Edge::TREE:
 404             fprintf(out, "\t%i -> %i;\n", idA, idB);
 405             break;
 406          case Graph::Edge::FORWARD:
 407             fprintf(out, "\t%i -> %i [color=green];\n", idA, idB);
 408             break;
 409          case Graph::Edge::CROSS:
 410             fprintf(out, "\t%i -> %i [color=red];\n", idA, idB);
 411             break;
 412          case Graph::Edge::BACK:
 413             fprintf(out, "\t%i -> %i;\n", idA, idB);
 414             break;
 415          case Graph::Edge::DUMMY:
 416             fprintf(out, "\t%i -> %i [style=dotted];\n", idA, idB);
 417             break;
 418          default:
 419             assert(0);
 420             break;
 421          }
 422       }
 423    }
 424    cfg.putIterator(iter);
 425
 426    fprintf(out, "}\n");
 427    fclose(out);
 428 }
 429
 430 } // namespace nv50_ir