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Diffstat (limited to 'lib/Transforms/Scalar/TailRecursionElimination.cpp')
-rw-r--r--lib/Transforms/Scalar/TailRecursionElimination.cpp71
1 files changed, 40 insertions, 31 deletions
diff --git a/lib/Transforms/Scalar/TailRecursionElimination.cpp b/lib/Transforms/Scalar/TailRecursionElimination.cpp
index 90c5c243f464..2a1106b41de2 100644
--- a/lib/Transforms/Scalar/TailRecursionElimination.cpp
+++ b/lib/Transforms/Scalar/TailRecursionElimination.cpp
@@ -60,6 +60,7 @@
#include "llvm/Analysis/InlineCost.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/Loads.h"
+#include "llvm/Analysis/OptimizationRemarkEmitter.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/CallSite.h"
@@ -78,7 +79,6 @@
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
-#include "llvm/Transforms/Utils/Local.h"
using namespace llvm;
#define DEBUG_TYPE "tailcallelim"
@@ -177,7 +177,8 @@ struct AllocaDerivedValueTracker {
};
}
-static bool markTails(Function &F, bool &AllCallsAreTailCalls) {
+static bool markTails(Function &F, bool &AllCallsAreTailCalls,
+ OptimizationRemarkEmitter *ORE) {
if (F.callsFunctionThatReturnsTwice())
return false;
AllCallsAreTailCalls = true;
@@ -228,7 +229,7 @@ static bool markTails(Function &F, bool &AllCallsAreTailCalls) {
Escaped = ESCAPED;
CallInst *CI = dyn_cast<CallInst>(&I);
- if (!CI || CI->isTailCall())
+ if (!CI || CI->isTailCall() || isa<DbgInfoIntrinsic>(&I))
continue;
bool IsNoTail = CI->isNoTailCall() || CI->hasOperandBundles();
@@ -252,9 +253,11 @@ static bool markTails(Function &F, bool &AllCallsAreTailCalls) {
break;
}
if (SafeToTail) {
- emitOptimizationRemark(
- F.getContext(), "tailcallelim", F, CI->getDebugLoc(),
- "marked this readnone call a tail call candidate");
+ using namespace ore;
+ ORE->emit([&]() {
+ return OptimizationRemark(DEBUG_TYPE, "tailcall-readnone", CI)
+ << "marked as tail call candidate (readnone)";
+ });
CI->setTailCall();
Modified = true;
continue;
@@ -299,9 +302,7 @@ static bool markTails(Function &F, bool &AllCallsAreTailCalls) {
if (Visited[CI->getParent()] != ESCAPED) {
// If the escape point was part way through the block, calls after the
// escape point wouldn't have been put into DeferredTails.
- emitOptimizationRemark(F.getContext(), "tailcallelim", F,
- CI->getDebugLoc(),
- "marked this call a tail call candidate");
+ DEBUG(dbgs() << "Marked as tail call candidate: " << *CI << "\n");
CI->setTailCall();
Modified = true;
} else {
@@ -330,7 +331,7 @@ static bool canMoveAboveCall(Instruction *I, CallInst *CI, AliasAnalysis *AA) {
// Writes to memory only matter if they may alias the pointer
// being loaded from.
const DataLayout &DL = L->getModule()->getDataLayout();
- if ((AA->getModRefInfo(CI, MemoryLocation::get(L)) & MRI_Mod) ||
+ if (isModSet(AA->getModRefInfo(CI, MemoryLocation::get(L))) ||
!isSafeToLoadUnconditionally(L->getPointerOperand(),
L->getAlignment(), DL, L))
return false;
@@ -491,7 +492,8 @@ static bool eliminateRecursiveTailCall(CallInst *CI, ReturnInst *Ret,
BasicBlock *&OldEntry,
bool &TailCallsAreMarkedTail,
SmallVectorImpl<PHINode *> &ArgumentPHIs,
- AliasAnalysis *AA) {
+ AliasAnalysis *AA,
+ OptimizationRemarkEmitter *ORE) {
// If we are introducing accumulator recursion to eliminate operations after
// the call instruction that are both associative and commutative, the initial
// value for the accumulator is placed in this variable. If this value is set
@@ -551,8 +553,11 @@ static bool eliminateRecursiveTailCall(CallInst *CI, ReturnInst *Ret,
BasicBlock *BB = Ret->getParent();
Function *F = BB->getParent();
- emitOptimizationRemark(F->getContext(), "tailcallelim", *F, CI->getDebugLoc(),
- "transforming tail recursion to loop");
+ using namespace ore;
+ ORE->emit([&]() {
+ return OptimizationRemark(DEBUG_TYPE, "tailcall-recursion", CI)
+ << "transforming tail recursion into loop";
+ });
// OK! We can transform this tail call. If this is the first one found,
// create the new entry block, allowing us to branch back to the old entry.
@@ -666,13 +671,11 @@ static bool eliminateRecursiveTailCall(CallInst *CI, ReturnInst *Ret,
return true;
}
-static bool foldReturnAndProcessPred(BasicBlock *BB, ReturnInst *Ret,
- BasicBlock *&OldEntry,
- bool &TailCallsAreMarkedTail,
- SmallVectorImpl<PHINode *> &ArgumentPHIs,
- bool CannotTailCallElimCallsMarkedTail,
- const TargetTransformInfo *TTI,
- AliasAnalysis *AA) {
+static bool foldReturnAndProcessPred(
+ BasicBlock *BB, ReturnInst *Ret, BasicBlock *&OldEntry,
+ bool &TailCallsAreMarkedTail, SmallVectorImpl<PHINode *> &ArgumentPHIs,
+ bool CannotTailCallElimCallsMarkedTail, const TargetTransformInfo *TTI,
+ AliasAnalysis *AA, OptimizationRemarkEmitter *ORE) {
bool Change = false;
// Make sure this block is a trivial return block.
@@ -708,7 +711,7 @@ static bool foldReturnAndProcessPred(BasicBlock *BB, ReturnInst *Ret,
BB->eraseFromParent();
eliminateRecursiveTailCall(CI, RI, OldEntry, TailCallsAreMarkedTail,
- ArgumentPHIs, AA);
+ ArgumentPHIs, AA, ORE);
++NumRetDuped;
Change = true;
}
@@ -722,23 +725,25 @@ static bool processReturningBlock(ReturnInst *Ret, BasicBlock *&OldEntry,
SmallVectorImpl<PHINode *> &ArgumentPHIs,
bool CannotTailCallElimCallsMarkedTail,
const TargetTransformInfo *TTI,
- AliasAnalysis *AA) {
+ AliasAnalysis *AA,
+ OptimizationRemarkEmitter *ORE) {
CallInst *CI = findTRECandidate(Ret, CannotTailCallElimCallsMarkedTail, TTI);
if (!CI)
return false;
return eliminateRecursiveTailCall(CI, Ret, OldEntry, TailCallsAreMarkedTail,
- ArgumentPHIs, AA);
+ ArgumentPHIs, AA, ORE);
}
static bool eliminateTailRecursion(Function &F, const TargetTransformInfo *TTI,
- AliasAnalysis *AA) {
+ AliasAnalysis *AA,
+ OptimizationRemarkEmitter *ORE) {
if (F.getFnAttribute("disable-tail-calls").getValueAsString() == "true")
return false;
bool MadeChange = false;
bool AllCallsAreTailCalls = false;
- MadeChange |= markTails(F, AllCallsAreTailCalls);
+ MadeChange |= markTails(F, AllCallsAreTailCalls, ORE);
if (!AllCallsAreTailCalls)
return MadeChange;
@@ -765,13 +770,13 @@ static bool eliminateTailRecursion(Function &F, const TargetTransformInfo *TTI,
for (Function::iterator BBI = F.begin(), E = F.end(); BBI != E; /*in loop*/) {
BasicBlock *BB = &*BBI++; // foldReturnAndProcessPred may delete BB.
if (ReturnInst *Ret = dyn_cast<ReturnInst>(BB->getTerminator())) {
- bool Change =
- processReturningBlock(Ret, OldEntry, TailCallsAreMarkedTail,
- ArgumentPHIs, !CanTRETailMarkedCall, TTI, AA);
+ bool Change = processReturningBlock(Ret, OldEntry, TailCallsAreMarkedTail,
+ ArgumentPHIs, !CanTRETailMarkedCall,
+ TTI, AA, ORE);
if (!Change && BB->getFirstNonPHIOrDbg() == Ret)
Change = foldReturnAndProcessPred(BB, Ret, OldEntry,
TailCallsAreMarkedTail, ArgumentPHIs,
- !CanTRETailMarkedCall, TTI, AA);
+ !CanTRETailMarkedCall, TTI, AA, ORE);
MadeChange |= Change;
}
}
@@ -802,6 +807,7 @@ struct TailCallElim : public FunctionPass {
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<TargetTransformInfoWrapperPass>();
AU.addRequired<AAResultsWrapperPass>();
+ AU.addRequired<OptimizationRemarkEmitterWrapperPass>();
AU.addPreserved<GlobalsAAWrapperPass>();
}
@@ -811,7 +817,8 @@ struct TailCallElim : public FunctionPass {
return eliminateTailRecursion(
F, &getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F),
- &getAnalysis<AAResultsWrapperPass>().getAAResults());
+ &getAnalysis<AAResultsWrapperPass>().getAAResults(),
+ &getAnalysis<OptimizationRemarkEmitterWrapperPass>().getORE());
}
};
}
@@ -820,6 +827,7 @@ char TailCallElim::ID = 0;
INITIALIZE_PASS_BEGIN(TailCallElim, "tailcallelim", "Tail Call Elimination",
false, false)
INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
+INITIALIZE_PASS_DEPENDENCY(OptimizationRemarkEmitterWrapperPass)
INITIALIZE_PASS_END(TailCallElim, "tailcallelim", "Tail Call Elimination",
false, false)
@@ -833,8 +841,9 @@ PreservedAnalyses TailCallElimPass::run(Function &F,
TargetTransformInfo &TTI = AM.getResult<TargetIRAnalysis>(F);
AliasAnalysis &AA = AM.getResult<AAManager>(F);
+ auto &ORE = AM.getResult<OptimizationRemarkEmitterAnalysis>(F);
- bool Changed = eliminateTailRecursion(F, &TTI, &AA);
+ bool Changed = eliminateTailRecursion(F, &TTI, &AA, &ORE);
if (!Changed)
return PreservedAnalyses::all();
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-07 20:48:52 +0000