Mercurial > hg > Members > tobaru > cbc > CbC_llvm

comparison lib/Analysis/GlobalsModRef.cpp @ 121:803732b1fca8

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LLVM 5.0
author kono
date Fri, 27 Oct 2017 17:07:41 +0900
parents 1172e4bd9c6f
children
comparison
equal deleted inserted replaced
120:1172e4bd9c6f 121:803732b1fca8
473 // visit all callees before callers (leaf-first). 473 // visit all callees before callers (leaf-first).
474 for (scc_iterator<CallGraph *> I = scc_begin(&CG); !I.isAtEnd(); ++I) { 474 for (scc_iterator<CallGraph *> I = scc_begin(&CG); !I.isAtEnd(); ++I) {
475 const std::vector<CallGraphNode *> &SCC = *I; 475 const std::vector<CallGraphNode *> &SCC = *I;
476 assert(!SCC.empty() && "SCC with no functions?"); 476 assert(!SCC.empty() && "SCC with no functions?");
477 477
478 if (!SCC[0]->getFunction() || !SCC[0]->getFunction()->isDefinitionExact()) { 478 Function *F = SCC[0]->getFunction();
479
480 if (!F || !F->isDefinitionExact()) {
479 // Calls externally or not exact - can't say anything useful. Remove any 481 // Calls externally or not exact - can't say anything useful. Remove any
480 // existing function records (may have been created when scanning 482 // existing function records (may have been created when scanning
481 // globals). 483 // globals).
482 for (auto *Node : SCC) 484 for (auto *Node : SCC)
483 FunctionInfos.erase(Node->getFunction()); 485 FunctionInfos.erase(Node->getFunction());
484 continue; 486 continue;
485 } 487 }
486 488
487 FunctionInfo &FI = FunctionInfos[SCC[0]->getFunction()]; 489 FunctionInfo &FI = FunctionInfos[F];
488 bool KnowNothing = false; 490 bool KnowNothing = false;
489 491
490 // Collect the mod/ref properties due to called functions. We only compute 492 // Collect the mod/ref properties due to called functions. We only compute
491 // one mod-ref set. 493 // one mod-ref set.
492 for (unsigned i = 0, e = SCC.size(); i != e && !KnowNothing; ++i) { 494 for (unsigned i = 0, e = SCC.size(); i != e && !KnowNothing; ++i) {
493 Function *F = SCC[i]->getFunction();
494 if (!F) { 495 if (!F) {
495 KnowNothing = true; 496 KnowNothing = true;
496 break; 497 break;
497 } 498 }
498 499
499 if (F->isDeclaration()) { 500 if (F->isDeclaration() || F->hasFnAttribute(Attribute::OptimizeNone)) {
500 // Try to get mod/ref behaviour from function attributes. 501 // Try to get mod/ref behaviour from function attributes.
501 if (F->doesNotAccessMemory()) { 502 if (F->doesNotAccessMemory()) {
502 // Can't do better than that! 503 // Can't do better than that!
503 } else if (F->onlyReadsMemory()) { 504 } else if (F->onlyReadsMemory()) {
504 FI.addModRefInfo(MRI_Ref); 505 FI.addModRefInfo(MRI_Ref);
543 544
544 // Scan the function bodies for explicit loads or stores. 545 // Scan the function bodies for explicit loads or stores.
545 for (auto *Node : SCC) { 546 for (auto *Node : SCC) {
546 if (FI.getModRefInfo() == MRI_ModRef) 547 if (FI.getModRefInfo() == MRI_ModRef)
547 break; // The mod/ref lattice saturates here. 548 break; // The mod/ref lattice saturates here.
549
550 // Don't prove any properties based on the implementation of an optnone
551 // function. Function attributes were already used as a best approximation
552 // above.
553 if (Node->getFunction()->hasFnAttribute(Attribute::OptimizeNone))
554 continue;
555
548 for (Instruction &I : instructions(Node->getFunction())) { 556 for (Instruction &I : instructions(Node->getFunction())) {
549 if (FI.getModRefInfo() == MRI_ModRef) 557 if (FI.getModRefInfo() == MRI_ModRef)
550 break; // The mod/ref lattice saturates here. 558 break; // The mod/ref lattice saturates here.
551 559
552 // We handle calls specially because the graph-relevant aspects are 560 // We handle calls specially because the graph-relevant aspects are