diff options
Diffstat (limited to 'llvm/lib/Analysis')
| -rw-r--r-- | llvm/lib/Analysis/LoopInfo.cpp | 62 |
1 files changed, 8 insertions, 54 deletions
diff --git a/llvm/lib/Analysis/LoopInfo.cpp b/llvm/lib/Analysis/LoopInfo.cpp index 0c725fcadff..30e1b73dbf2 100644 --- a/llvm/lib/Analysis/LoopInfo.cpp +++ b/llvm/lib/Analysis/LoopInfo.cpp @@ -54,29 +54,16 @@ static const char *const LoopMDName = "llvm.loop"; // Loop implementation // -/// isLoopInvariant - Return true if the specified value is loop invariant -/// bool Loop::isLoopInvariant(const Value *V) const { if (const Instruction *I = dyn_cast<Instruction>(V)) return !contains(I); return true; // All non-instructions are loop invariant } -/// hasLoopInvariantOperands - Return true if all the operands of the -/// specified instruction are loop invariant. bool Loop::hasLoopInvariantOperands(const Instruction *I) const { return all_of(I->operands(), [this](Value *V) { return isLoopInvariant(V); }); } -/// makeLoopInvariant - If the given value is an instruciton inside of the -/// loop and it can be hoisted, do so to make it trivially loop-invariant. -/// Return true if the value after any hoisting is loop invariant. This -/// function can be used as a slightly more aggressive replacement for -/// isLoopInvariant. -/// -/// If InsertPt is specified, it is the point to hoist instructions to. -/// If null, the terminator of the loop preheader is used. -/// bool Loop::makeLoopInvariant(Value *V, bool &Changed, Instruction *InsertPt) const { if (Instruction *I = dyn_cast<Instruction>(V)) @@ -84,15 +71,6 @@ bool Loop::makeLoopInvariant(Value *V, bool &Changed, return true; // All non-instructions are loop-invariant. } -/// makeLoopInvariant - If the given instruction is inside of the -/// loop and it can be hoisted, do so to make it trivially loop-invariant. -/// Return true if the instruction after any hoisting is loop invariant. This -/// function can be used as a slightly more aggressive replacement for -/// isLoopInvariant. -/// -/// If InsertPt is specified, it is the point to hoist instructions to. -/// If null, the terminator of the loop preheader is used. -/// bool Loop::makeLoopInvariant(Instruction *I, bool &Changed, Instruction *InsertPt) const { // Test if the value is already loop-invariant. @@ -131,14 +109,6 @@ bool Loop::makeLoopInvariant(Instruction *I, bool &Changed, return true; } -/// getCanonicalInductionVariable - Check to see if the loop has a canonical -/// induction variable: an integer recurrence that starts at 0 and increments -/// by one each time through the loop. If so, return the phi node that -/// corresponds to it. -/// -/// The IndVarSimplify pass transforms loops to have a canonical induction -/// variable. -/// PHINode *Loop::getCanonicalInductionVariable() const { BasicBlock *H = getHeader(); @@ -175,7 +145,6 @@ PHINode *Loop::getCanonicalInductionVariable() const { return nullptr; } -/// isLCSSAForm - Return true if the Loop is in LCSSA form bool Loop::isLCSSAForm(DominatorTree &DT) const { for (block_iterator BI = block_begin(), E = block_end(); BI != E; ++BI) { BasicBlock *BB = *BI; @@ -216,17 +185,13 @@ bool Loop::isRecursivelyLCSSAForm(DominatorTree &DT) const { }); } -/// isLoopSimplifyForm - Return true if the Loop is in the form that -/// the LoopSimplify form transforms loops to, which is sometimes called -/// normal form. bool Loop::isLoopSimplifyForm() const { // Normal-form loops have a preheader, a single backedge, and all of their // exits have all their predecessors inside the loop. return getLoopPreheader() && getLoopLatch() && hasDedicatedExits(); } -/// isSafeToClone - Return true if the loop body is safe to clone in practice. -/// Routines that reform the loop CFG and split edges often fail on indirectbr. +// Routines that reform the loop CFG and split edges often fail on indirectbr. bool Loop::isSafeToClone() const { // Return false if any loop blocks contain indirectbrs, or there are any calls // to noduplicate functions. @@ -353,9 +318,6 @@ bool Loop::isAnnotatedParallel() const { return true; } - -/// hasDedicatedExits - Return true if no exit block for the loop -/// has a predecessor that is outside the loop. bool Loop::hasDedicatedExits() const { // Each predecessor of each exit block of a normal loop is contained // within the loop. @@ -370,10 +332,6 @@ bool Loop::hasDedicatedExits() const { return true; } -/// getUniqueExitBlocks - Return all unique successor blocks of this loop. -/// These are the blocks _outside of the current loop_ which are branched to. -/// This assumes that loop exits are in canonical form. -/// void Loop::getUniqueExitBlocks(SmallVectorImpl<BasicBlock *> &ExitBlocks) const { assert(hasDedicatedExits() && @@ -421,8 +379,6 @@ Loop::getUniqueExitBlocks(SmallVectorImpl<BasicBlock *> &ExitBlocks) const { } } -/// getUniqueExitBlock - If getUniqueExitBlocks would return exactly one -/// block, return that block. Otherwise return null. BasicBlock *Loop::getUniqueExitBlock() const { SmallVector<BasicBlock *, 8> UniqueExitBlocks; getUniqueExitBlocks(UniqueExitBlocks); @@ -475,8 +431,8 @@ protected: }; } // end anonymous namespace -/// updateBlockParents - Update the parent loop for all blocks that are directly -/// contained within the original "unloop". +/// Update the parent loop for all blocks that are directly contained within the +/// original "unloop". void UnloopUpdater::updateBlockParents() { if (Unloop->getNumBlocks()) { // Perform a post order CFG traversal of all blocks within this loop, @@ -525,8 +481,7 @@ void UnloopUpdater::updateBlockParents() { } } -/// removeBlocksFromAncestors - Remove unloop's blocks from all ancestors below -/// their new parents. +/// Remove unloop's blocks from all ancestors below their new parents. void UnloopUpdater::removeBlocksFromAncestors() { // Remove all unloop's blocks (including those in nested subloops) from // ancestors below the new parent loop. @@ -548,8 +503,7 @@ void UnloopUpdater::removeBlocksFromAncestors() { } } -/// updateSubloopParents - Update the parent loop for all subloops directly -/// nested within unloop. +/// Update the parent loop for all subloops directly nested within unloop. void UnloopUpdater::updateSubloopParents() { while (!Unloop->empty()) { Loop *Subloop = *std::prev(Unloop->end()); @@ -563,9 +517,9 @@ void UnloopUpdater::updateSubloopParents() { } } -/// getNearestLoop - Return the nearest parent loop among this block's -/// successors. If a successor is a subloop header, consider its parent to be -/// the nearest parent of the subloop's exits. +/// Return the nearest parent loop among this block's successors. If a successor +/// is a subloop header, consider its parent to be the nearest parent of the +/// subloop's exits. /// /// For subloop blocks, simply update SubloopParents and return NULL. Loop *UnloopUpdater::getNearestLoop(BasicBlock *BB, Loop *BBLoop) { |
