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-rw-r--r--lib/Transforms/Utils/LoopSimplify.cpp42
1 files changed, 19 insertions, 23 deletions
diff --git a/lib/Transforms/Utils/LoopSimplify.cpp b/lib/Transforms/Utils/LoopSimplify.cpp
index 47083ea..f7787da 100644
--- a/lib/Transforms/Utils/LoopSimplify.cpp
+++ b/lib/Transforms/Utils/LoopSimplify.cpp
@@ -37,7 +37,6 @@
//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "loop-simplify"
#include "llvm/Transforms/Scalar.h"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/SetOperations.h"
@@ -63,6 +62,8 @@
#include "llvm/Transforms/Utils/LoopUtils.h"
using namespace llvm;
+#define DEBUG_TYPE "loop-simplify"
+
STATISTIC(NumInserted, "Number of pre-header or exit blocks inserted");
STATISTIC(NumNested , "Number of nested loops split out");
@@ -85,7 +86,7 @@ static void placeSplitBlockCarefully(BasicBlock *NewBB,
// Figure out *which* outside block to put this after. Prefer an outside
// block that neighbors a BB actually in the loop.
- BasicBlock *FoundBB = 0;
+ BasicBlock *FoundBB = nullptr;
for (unsigned i = 0, e = SplitPreds.size(); i != e; ++i) {
Function::iterator BBI = SplitPreds[i];
if (++BBI != NewBB->getParent()->end() &&
@@ -119,7 +120,7 @@ BasicBlock *llvm::InsertPreheaderForLoop(Loop *L, Pass *PP) {
// If the loop is branched to from an indirect branch, we won't
// be able to fully transform the loop, because it prohibits
// edge splitting.
- if (isa<IndirectBrInst>(P->getTerminator())) return 0;
+ if (isa<IndirectBrInst>(P->getTerminator())) return nullptr;
// Keep track of it.
OutsideBlocks.push_back(P);
@@ -160,14 +161,14 @@ static BasicBlock *rewriteLoopExitBlock(Loop *L, BasicBlock *Exit, Pass *PP) {
BasicBlock *P = *I;
if (L->contains(P)) {
// Don't do this if the loop is exited via an indirect branch.
- if (isa<IndirectBrInst>(P->getTerminator())) return 0;
+ if (isa<IndirectBrInst>(P->getTerminator())) return nullptr;
LoopBlocks.push_back(P);
}
}
assert(!LoopBlocks.empty() && "No edges coming in from outside the loop?");
- BasicBlock *NewExitBB = 0;
+ BasicBlock *NewExitBB = nullptr;
if (Exit->isLandingPad()) {
SmallVector<BasicBlock*, 2> NewBBs;
@@ -211,7 +212,7 @@ static PHINode *findPHIToPartitionLoops(Loop *L, AliasAnalysis *AA,
for (BasicBlock::iterator I = L->getHeader()->begin(); isa<PHINode>(I); ) {
PHINode *PN = cast<PHINode>(I);
++I;
- if (Value *V = SimplifyInstruction(PN, 0, 0, DT)) {
+ if (Value *V = SimplifyInstruction(PN, nullptr, nullptr, DT)) {
// This is a degenerate PHI already, don't modify it!
PN->replaceAllUsesWith(V);
if (AA) AA->deleteValue(PN);
@@ -226,7 +227,7 @@ static PHINode *findPHIToPartitionLoops(Loop *L, AliasAnalysis *AA,
// We found something tasty to remove.
return PN;
}
- return 0;
+ return nullptr;
}
/// \brief If this loop has multiple backedges, try to pull one of them out into
@@ -253,14 +254,14 @@ static Loop *separateNestedLoop(Loop *L, BasicBlock *Preheader,
LoopInfo *LI, ScalarEvolution *SE, Pass *PP) {
// Don't try to separate loops without a preheader.
if (!Preheader)
- return 0;
+ return nullptr;
// The header is not a landing pad; preheader insertion should ensure this.
assert(!L->getHeader()->isLandingPad() &&
"Can't insert backedge to landing pad");
PHINode *PN = findPHIToPartitionLoops(L, AA, DT);
- if (PN == 0) return 0; // No known way to partition.
+ if (!PN) return nullptr; // No known way to partition.
// Pull out all predecessors that have varying values in the loop. This
// handles the case when a PHI node has multiple instances of itself as
@@ -271,7 +272,7 @@ static Loop *separateNestedLoop(Loop *L, BasicBlock *Preheader,
!L->contains(PN->getIncomingBlock(i))) {
// We can't split indirectbr edges.
if (isa<IndirectBrInst>(PN->getIncomingBlock(i)->getTerminator()))
- return 0;
+ return nullptr;
OuterLoopPreds.push_back(PN->getIncomingBlock(i));
}
}
@@ -362,7 +363,7 @@ static BasicBlock *insertUniqueBackedgeBlock(Loop *L, BasicBlock *Preheader,
// Unique backedge insertion currently depends on having a preheader.
if (!Preheader)
- return 0;
+ return nullptr;
// The header is not a landing pad; preheader insertion should ensure this.
assert(!Header->isLandingPad() && "Can't insert backedge to landing pad");
@@ -374,7 +375,7 @@ static BasicBlock *insertUniqueBackedgeBlock(Loop *L, BasicBlock *Preheader,
// Indirectbr edges cannot be split, so we must fail if we find one.
if (isa<IndirectBrInst>(P->getTerminator()))
- return 0;
+ return nullptr;
if (P != Preheader) BackedgeBlocks.push_back(P);
}
@@ -403,7 +404,7 @@ static BasicBlock *insertUniqueBackedgeBlock(Loop *L, BasicBlock *Preheader,
// preheader over to the new PHI node.
unsigned PreheaderIdx = ~0U;
bool HasUniqueIncomingValue = true;
- Value *UniqueValue = 0;
+ Value *UniqueValue = nullptr;
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
BasicBlock *IBB = PN->getIncomingBlock(i);
Value *IV = PN->getIncomingValue(i);
@@ -412,7 +413,7 @@ static BasicBlock *insertUniqueBackedgeBlock(Loop *L, BasicBlock *Preheader,
} else {
NewPN->addIncoming(IV, IBB);
if (HasUniqueIncomingValue) {
- if (UniqueValue == 0)
+ if (!UniqueValue)
UniqueValue = IV;
else if (UniqueValue != IV)
HasUniqueIncomingValue = false;
@@ -609,7 +610,7 @@ ReprocessLoop:
PHINode *PN;
for (BasicBlock::iterator I = L->getHeader()->begin();
(PN = dyn_cast<PHINode>(I++)); )
- if (Value *V = SimplifyInstruction(PN, 0, 0, DT)) {
+ if (Value *V = SimplifyInstruction(PN, nullptr, nullptr, DT)) {
if (AA) AA->deleteValue(PN);
if (SE) SE->forgetValue(PN);
PN->replaceAllUsesWith(V);
@@ -653,7 +654,8 @@ ReprocessLoop:
if (Inst == CI)
continue;
if (!L->makeLoopInvariant(Inst, AnyInvariant,
- Preheader ? Preheader->getTerminator() : 0)) {
+ Preheader ? Preheader->getTerminator()
+ : nullptr)) {
AllInvariant = false;
break;
}
@@ -761,12 +763,6 @@ namespace {
/// verifyAnalysis() - Verify LoopSimplifyForm's guarantees.
void verifyAnalysis() const override;
-
- private:
- bool ProcessLoop(Loop *L);
- BasicBlock *RewriteLoopExitBlock(Loop *L, BasicBlock *Exit);
- Loop *SeparateNestedLoop(Loop *L, BasicBlock *Preheader);
- BasicBlock *InsertUniqueBackedgeBlock(Loop *L, BasicBlock *Preheader);
};
}
@@ -782,7 +778,7 @@ INITIALIZE_PASS_END(LoopSimplify, "loop-simplify",
char &llvm::LoopSimplifyID = LoopSimplify::ID;
Pass *llvm::createLoopSimplifyPass() { return new LoopSimplify(); }
-/// runOnLoop - Run down all loops in the CFG (recursively, but we could do
+/// runOnFunction - Run down all loops in the CFG (recursively, but we could do
/// it in any convenient order) inserting preheaders...
///
bool LoopSimplify::runOnFunction(Function &F) {
generated by cgit v1.1 at 2024-05-21 13:02:09 +0000