[llvm] r314308 - [SimplifyCFG] add a struct to house optional folds (PR34603)
Sanjay Patel via llvm-commits
llvm-commits at lists.llvm.org
Wed Sep 27 07:54:16 PDT 2017
Author: spatel
Date: Wed Sep 27 07:54:16 2017
New Revision: 314308
URL: http://llvm.org/viewvc/llvm-project?rev=314308&view=rev
Log:
[SimplifyCFG] add a struct to house optional folds (PR34603)
This was intended to be no-functional-change, but it's not - there's a test diff.
So I thought I should stop here and post it as-is to see if this looks like what was expected
based on the discussion in PR34603:
https://bugs.llvm.org/show_bug.cgi?id=34603
Notes:
1. The test improvement occurs because the existing 'LateSimplifyCFG' marker is not carried
through the recursive calls to 'SimplifyCFG()->SimplifyCFGOpt().run()->SimplifyCFG()'.
The parameter isn't passed down, so we pick up the default value from the function signature
after the first level. I assumed that was a bug, so I've passed 'Options' down in all of the
'SimplifyCFG' calls.
2. I split 'LateSimplifyCFG' into 2 bits: ConvertSwitchToLookupTable and KeepCanonicalLoops.
This would theoretically allow us to differentiate the transforms controlled by those params
independently.
3. We could stash the optional AssumptionCache pointer and 'LoopHeaders' pointer in the struct too.
I just stopped here to minimize the diffs.
4. Similarly, I stopped short of messing with the pass manager layer. I have another question that
could wait for the follow-up: why is the new pass manager creating the pass with LateSimplifyCFG
set to true no matter where in the pipeline it's creating SimplifyCFG passes?
// Create an early function pass manager to cleanup the output of the
// frontend.
EarlyFPM.addPass(SimplifyCFGPass());
-->
/// \brief Construct a pass with the default thresholds
/// and switch optimizations.
SimplifyCFGPass::SimplifyCFGPass()
: BonusInstThreshold(UserBonusInstThreshold),
LateSimplifyCFG(true) {} <-- switches get converted to lookup tables and loops may not be in canonical form
If this is unintended, then it's possible that the current behavior of dropping the 'LateSimplifyCFG'
setting via recursion was masking this bug.
Differential Revision: https://reviews.llvm.org/D38138
Modified:
llvm/trunk/include/llvm/Transforms/Scalar/SimplifyCFG.h
llvm/trunk/include/llvm/Transforms/Utils/Local.h
llvm/trunk/lib/CodeGen/DwarfEHPrepare.cpp
llvm/trunk/lib/Target/AMDGPU/AMDGPUUnifyDivergentExitNodes.cpp
llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp
llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp
llvm/trunk/test/Transforms/SimplifyCFG/X86/switch_to_lookup_table.ll
llvm/trunk/tools/bugpoint/CrashDebugger.cpp
Modified: llvm/trunk/include/llvm/Transforms/Scalar/SimplifyCFG.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Scalar/SimplifyCFG.h?rev=314308&r1=314307&r2=314308&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/Scalar/SimplifyCFG.h (original)
+++ llvm/trunk/include/llvm/Transforms/Scalar/SimplifyCFG.h Wed Sep 27 07:54:16 2017
@@ -17,26 +17,25 @@
#include "llvm/IR/Function.h"
#include "llvm/IR/PassManager.h"
+#include "llvm/Transforms/Utils/Local.h"
namespace llvm {
-/// \brief A pass to simplify and canonicalize the CFG of a function.
+/// A pass to simplify and canonicalize the CFG of a function.
///
-/// This pass iteratively simplifies the entire CFG of a function, removing
-/// unnecessary control flows and bringing it into the canonical form expected
-/// by the rest of the mid-level optimizer.
+/// This pass iteratively simplifies the entire CFG of a function. It may change
+/// or remove control flow to put the CFG into a canonical form expected by
+/// other passes of the mid-level optimizer. Depending on the specified options,
+/// it may further optimize control-flow to create non-canonical forms.
class SimplifyCFGPass : public PassInfoMixin<SimplifyCFGPass> {
- int BonusInstThreshold;
- bool LateSimplifyCFG;
+ SimplifyCFGOptions Options;
public:
- /// \brief Construct a pass with the default thresholds
- /// and switch optimizations.
+ /// Construct a pass with default options.
SimplifyCFGPass();
- /// \brief Construct a pass with a specific bonus threshold
- /// and optional switch optimizations.
- SimplifyCFGPass(int BonusInstThreshold, bool LateSimplifyCFG);
+ /// Construct a pass with optional optimizations.
+ SimplifyCFGPass(const SimplifyCFGOptions &PassOptions);
/// \brief Run the pass over the function.
PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
Modified: llvm/trunk/include/llvm/Transforms/Utils/Local.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Utils/Local.h?rev=314308&r1=314307&r2=314308&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/Utils/Local.h (original)
+++ llvm/trunk/include/llvm/Transforms/Utils/Local.h Wed Sep 27 07:54:16 2017
@@ -51,6 +51,22 @@ class LazyValueInfo;
template<typename T> class SmallVectorImpl;
+/// A set of parameters used to control the transforms in the SimplifyCFG pass.
+/// Options may change depending on the position in the optimization pipeline.
+/// For example, canonical form that includes switches and branches may later be
+/// replaced by lookup tables and selects.
+struct SimplifyCFGOptions {
+ int BonusInstThreshold;
+ bool ConvertSwitchToLookupTable;
+ bool NeedCanonicalLoop;
+
+ SimplifyCFGOptions(int BonusThreshold = 1, bool SwitchToLookup = false,
+ bool CanonicalLoops = true)
+ : BonusInstThreshold(BonusThreshold),
+ ConvertSwitchToLookupTable(SwitchToLookup),
+ NeedCanonicalLoop(CanonicalLoops) {}
+};
+
//===----------------------------------------------------------------------===//
// Local constant propagation.
//
@@ -135,17 +151,16 @@ bool TryToSimplifyUncondBranchFromEmptyB
/// values, but instcombine orders them so it usually won't matter.
bool EliminateDuplicatePHINodes(BasicBlock *BB);
-/// This function is used to do simplification of a CFG. For
-/// example, it adjusts branches to branches to eliminate the extra hop, it
-/// eliminates unreachable basic blocks, and does other "peephole" optimization
-/// of the CFG. It returns true if a modification was made, possibly deleting
-/// the basic block that was pointed to. LoopHeaders is an optional input
-/// parameter, providing the set of loop header that SimplifyCFG should not
-/// eliminate.
+/// This function is used to do simplification of a CFG. For example, it
+/// adjusts branches to branches to eliminate the extra hop, it eliminates
+/// unreachable basic blocks, and does other peephole optimization of the CFG.
+/// It returns true if a modification was made, possibly deleting the basic
+/// block that was pointed to. LoopHeaders is an optional input parameter
+/// providing the set of loop headers that SimplifyCFG should not eliminate.
bool SimplifyCFG(BasicBlock *BB, const TargetTransformInfo &TTI,
- unsigned BonusInstThreshold, AssumptionCache *AC = nullptr,
- SmallPtrSetImpl<BasicBlock *> *LoopHeaders = nullptr,
- bool LateSimplifyCFG = false);
+ AssumptionCache *AC = nullptr,
+ const SimplifyCFGOptions &Options = {},
+ SmallPtrSetImpl<BasicBlock *> *LoopHeaders = nullptr);
/// This function is used to flatten a CFG. For example, it uses parallel-and
/// and parallel-or mode to collapse if-conditions and merge if-regions with
Modified: llvm/trunk/lib/CodeGen/DwarfEHPrepare.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/DwarfEHPrepare.cpp?rev=314308&r1=314307&r2=314308&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/DwarfEHPrepare.cpp (original)
+++ llvm/trunk/lib/CodeGen/DwarfEHPrepare.cpp Wed Sep 27 07:54:16 2017
@@ -172,7 +172,7 @@ size_t DwarfEHPrepare::pruneUnreachableR
BasicBlock *BB = RI->getParent();
new UnreachableInst(Ctx, RI);
RI->eraseFromParent();
- SimplifyCFG(BB, TTI, 1);
+ SimplifyCFG(BB, TTI);
}
}
Resumes.resize(ResumesLeft);
Modified: llvm/trunk/lib/Target/AMDGPU/AMDGPUUnifyDivergentExitNodes.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AMDGPU/AMDGPUUnifyDivergentExitNodes.cpp?rev=314308&r1=314307&r2=314308&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AMDGPU/AMDGPUUnifyDivergentExitNodes.cpp (original)
+++ llvm/trunk/lib/Target/AMDGPU/AMDGPUUnifyDivergentExitNodes.cpp Wed Sep 27 07:54:16 2017
@@ -142,7 +142,7 @@ static BasicBlock *unifyReturnBlockSet(F
for (BasicBlock *BB : ReturningBlocks) {
// Cleanup possible branch to unconditional branch to the return.
- SimplifyCFG(BB, TTI, 2);
+ SimplifyCFG(BB, TTI, nullptr, {2});
}
return NewRetBlock;
Modified: llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp?rev=314308&r1=314307&r2=314308&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp Wed Sep 27 07:54:16 2017
@@ -130,8 +130,7 @@ static bool mergeEmptyReturnBlocks(Funct
/// iterating until no more changes are made.
static bool iterativelySimplifyCFG(Function &F, const TargetTransformInfo &TTI,
AssumptionCache *AC,
- unsigned BonusInstThreshold,
- bool LateSimplifyCFG) {
+ const SimplifyCFGOptions &Options) {
bool Changed = false;
bool LocalChange = true;
@@ -146,7 +145,7 @@ static bool iterativelySimplifyCFG(Funct
// Loop over all of the basic blocks and remove them if they are unneeded.
for (Function::iterator BBIt = F.begin(); BBIt != F.end(); ) {
- if (SimplifyCFG(&*BBIt++, TTI, BonusInstThreshold, AC, &LoopHeaders, LateSimplifyCFG)) {
+ if (SimplifyCFG(&*BBIt++, TTI, AC, Options, &LoopHeaders)) {
LocalChange = true;
++NumSimpl;
}
@@ -157,12 +156,11 @@ static bool iterativelySimplifyCFG(Funct
}
static bool simplifyFunctionCFG(Function &F, const TargetTransformInfo &TTI,
- AssumptionCache *AC, int BonusInstThreshold,
- bool LateSimplifyCFG) {
+ AssumptionCache *AC,
+ const SimplifyCFGOptions &Options) {
bool EverChanged = removeUnreachableBlocks(F);
EverChanged |= mergeEmptyReturnBlocks(F);
- EverChanged |= iterativelySimplifyCFG(F, TTI, AC, BonusInstThreshold,
- LateSimplifyCFG);
+ EverChanged |= iterativelySimplifyCFG(F, TTI, AC, Options);
// If neither pass changed anything, we're done.
if (!EverChanged) return false;
@@ -176,8 +174,7 @@ static bool simplifyFunctionCFG(Function
return true;
do {
- EverChanged = iterativelySimplifyCFG(F, TTI, AC, BonusInstThreshold,
- LateSimplifyCFG);
+ EverChanged = iterativelySimplifyCFG(F, TTI, AC, Options);
EverChanged |= removeUnreachableBlocks(F);
} while (EverChanged);
@@ -185,19 +182,17 @@ static bool simplifyFunctionCFG(Function
}
SimplifyCFGPass::SimplifyCFGPass()
- : BonusInstThreshold(UserBonusInstThreshold),
- LateSimplifyCFG(true) {}
+ : Options(UserBonusInstThreshold, true, false) {}
-SimplifyCFGPass::SimplifyCFGPass(int BonusInstThreshold, bool LateSimplifyCFG)
- : BonusInstThreshold(BonusInstThreshold),
- LateSimplifyCFG(LateSimplifyCFG) {}
+SimplifyCFGPass::SimplifyCFGPass(const SimplifyCFGOptions &PassOptions)
+ : Options(PassOptions) {}
PreservedAnalyses SimplifyCFGPass::run(Function &F,
FunctionAnalysisManager &AM) {
auto &TTI = AM.getResult<TargetIRAnalysis>(F);
auto &AC = AM.getResult<AssumptionAnalysis>(F);
- if (!simplifyFunctionCFG(F, TTI, &AC, BonusInstThreshold, LateSimplifyCFG))
+ if (!simplifyFunctionCFG(F, TTI, &AC, Options))
return PreservedAnalyses::all();
PreservedAnalyses PA;
PA.preserve<GlobalsAA>();
@@ -206,16 +201,17 @@ PreservedAnalyses SimplifyCFGPass::run(F
namespace {
struct BaseCFGSimplifyPass : public FunctionPass {
- unsigned BonusInstThreshold;
std::function<bool(const Function &)> PredicateFtor;
- bool LateSimplifyCFG;
+ int BonusInstThreshold;
+ bool ConvertSwitchToLookupTable;
+ bool KeepCanonicalLoops;
- BaseCFGSimplifyPass(int T, bool LateSimplifyCFG,
- std::function<bool(const Function &)> Ftor,
- char &ID)
+ BaseCFGSimplifyPass(int T, bool ConvertSwitch, bool KeepLoops,
+ std::function<bool(const Function &)> Ftor, char &ID)
: FunctionPass(ID), PredicateFtor(std::move(Ftor)),
- LateSimplifyCFG(LateSimplifyCFG) {
- BonusInstThreshold = (T == -1) ? UserBonusInstThreshold : unsigned(T);
+ ConvertSwitchToLookupTable(ConvertSwitch),
+ KeepCanonicalLoops(KeepLoops) {
+ BonusInstThreshold = (T == -1) ? UserBonusInstThreshold : T;
}
bool runOnFunction(Function &F) override {
if (skipFunction(F) || (PredicateFtor && !PredicateFtor(F)))
@@ -225,7 +221,9 @@ struct BaseCFGSimplifyPass : public Func
&getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
const TargetTransformInfo &TTI =
getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
- return simplifyFunctionCFG(F, TTI, AC, BonusInstThreshold, LateSimplifyCFG);
+ return simplifyFunctionCFG(
+ F, TTI, AC,
+ {BonusInstThreshold, ConvertSwitchToLookupTable, KeepCanonicalLoops});
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
@@ -240,7 +238,7 @@ struct CFGSimplifyPass : public BaseCFGS
CFGSimplifyPass(int T = -1,
std::function<bool(const Function &)> Ftor = nullptr)
- : BaseCFGSimplifyPass(T, false, Ftor, ID) {
+ : BaseCFGSimplifyPass(T, false, true, Ftor, ID) {
initializeCFGSimplifyPassPass(*PassRegistry::getPassRegistry());
}
};
@@ -250,7 +248,7 @@ struct LateCFGSimplifyPass : public Base
LateCFGSimplifyPass(int T = -1,
std::function<bool(const Function &)> Ftor = nullptr)
- : BaseCFGSimplifyPass(T, true, Ftor, ID) {
+ : BaseCFGSimplifyPass(T, true, false, Ftor, ID) {
initializeLateCFGSimplifyPassPass(*PassRegistry::getPassRegistry());
}
};
Modified: llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp?rev=314308&r1=314307&r2=314308&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp Wed Sep 27 07:54:16 2017
@@ -167,11 +167,10 @@ struct ValueEqualityComparisonCase {
class SimplifyCFGOpt {
const TargetTransformInfo &TTI;
const DataLayout &DL;
- unsigned BonusInstThreshold;
AssumptionCache *AC;
SmallPtrSetImpl<BasicBlock *> *LoopHeaders;
- // See comments in SimplifyCFGOpt::SimplifySwitch.
- bool LateSimplifyCFG;
+ const SimplifyCFGOptions &Options;
+
Value *isValueEqualityComparison(TerminatorInst *TI);
BasicBlock *GetValueEqualityComparisonCases(
TerminatorInst *TI, std::vector<ValueEqualityComparisonCase> &Cases);
@@ -194,11 +193,10 @@ class SimplifyCFGOpt {
public:
SimplifyCFGOpt(const TargetTransformInfo &TTI, const DataLayout &DL,
- unsigned BonusInstThreshold, AssumptionCache *AC,
+ AssumptionCache *AC,
SmallPtrSetImpl<BasicBlock *> *LoopHeaders,
- bool LateSimplifyCFG)
- : TTI(TTI), DL(DL), BonusInstThreshold(BonusInstThreshold), AC(AC),
- LoopHeaders(LoopHeaders), LateSimplifyCFG(LateSimplifyCFG) {}
+ const SimplifyCFGOptions &Opts)
+ : TTI(TTI), DL(DL), AC(AC), LoopHeaders(LoopHeaders), Options(Opts) {}
bool run(BasicBlock *BB);
};
@@ -3491,8 +3489,8 @@ static bool SimplifyIndirectBrOnSelect(I
/// the PHI, merging the third icmp into the switch.
static bool TryToSimplifyUncondBranchWithICmpInIt(
ICmpInst *ICI, IRBuilder<> &Builder, const DataLayout &DL,
- const TargetTransformInfo &TTI, unsigned BonusInstThreshold,
- AssumptionCache *AC) {
+ const TargetTransformInfo &TTI, AssumptionCache *AC,
+ const SimplifyCFGOptions &Options) {
BasicBlock *BB = ICI->getParent();
// If the block has any PHIs in it or the icmp has multiple uses, it is too
@@ -3527,7 +3525,7 @@ static bool TryToSimplifyUncondBranchWit
ICI->eraseFromParent();
}
// BB is now empty, so it is likely to simplify away.
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
}
// Ok, the block is reachable from the default dest. If the constant we're
@@ -3543,7 +3541,7 @@ static bool TryToSimplifyUncondBranchWit
ICI->replaceAllUsesWith(V);
ICI->eraseFromParent();
// BB is now empty, so it is likely to simplify away.
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
}
// The use of the icmp has to be in the 'end' block, by the only PHI node in
@@ -5522,12 +5520,12 @@ bool SimplifyCFGOpt::SimplifySwitch(Swit
// see if that predecessor totally determines the outcome of this switch.
if (BasicBlock *OnlyPred = BB->getSinglePredecessor())
if (SimplifyEqualityComparisonWithOnlyPredecessor(SI, OnlyPred, Builder))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
Value *Cond = SI->getCondition();
if (SelectInst *Select = dyn_cast<SelectInst>(Cond))
if (SimplifySwitchOnSelect(SI, Select))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
// If the block only contains the switch, see if we can fold the block
// away into any preds.
@@ -5537,33 +5535,34 @@ bool SimplifyCFGOpt::SimplifySwitch(Swit
++BBI;
if (SI == &*BBI)
if (FoldValueComparisonIntoPredecessors(SI, Builder))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
}
// Try to transform the switch into an icmp and a branch.
if (TurnSwitchRangeIntoICmp(SI, Builder))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
// Remove unreachable cases.
if (EliminateDeadSwitchCases(SI, AC, DL))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
if (SwitchToSelect(SI, Builder, AC, DL, TTI))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
if (ForwardSwitchConditionToPHI(SI))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
// The conversion from switch to lookup tables results in difficult-to-analyze
// code and makes pruning branches much harder. This is a problem if the
// switch expression itself can still be restricted as a result of inlining or
// CVP. Therefore, only apply this transformation during late stages of the
// optimisation pipeline.
- if (LateSimplifyCFG && SwitchToLookupTable(SI, Builder, DL, TTI))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ if (Options.ConvertSwitchToLookupTable &&
+ SwitchToLookupTable(SI, Builder, DL, TTI))
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
if (ReduceSwitchRange(SI, Builder, DL, TTI))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
return false;
}
@@ -5601,7 +5600,7 @@ bool SimplifyCFGOpt::SimplifyIndirectBr(
if (SelectInst *SI = dyn_cast<SelectInst>(IBI->getAddress())) {
if (SimplifyIndirectBrOnSelect(IBI, SI))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
}
return Changed;
}
@@ -5697,7 +5696,7 @@ bool SimplifyCFGOpt::SimplifyUncondBranc
// vectorization to keep canonical loop forms for nested loops. These blocks
// can be eliminated when the pass is invoked later in the back-end.)
bool NeedCanonicalLoop =
- !LateSimplifyCFG &&
+ Options.NeedCanonicalLoop &&
(LoopHeaders && (LoopHeaders->count(BB) || LoopHeaders->count(Succ)));
BasicBlock::iterator I = BB->getFirstNonPHIOrDbg()->getIterator();
if (I->isTerminator() && BB != &BB->getParent()->getEntryBlock() &&
@@ -5711,8 +5710,8 @@ bool SimplifyCFGOpt::SimplifyUncondBranc
for (++I; isa<DbgInfoIntrinsic>(I); ++I)
;
if (I->isTerminator() &&
- TryToSimplifyUncondBranchWithICmpInIt(ICI, Builder, DL, TTI,
- BonusInstThreshold, AC))
+ TryToSimplifyUncondBranchWithICmpInIt(ICI, Builder, DL, TTI, AC,
+ Options))
return true;
}
@@ -5729,8 +5728,8 @@ bool SimplifyCFGOpt::SimplifyUncondBranc
// branches to us and our successor, fold the comparison into the
// predecessor and use logical operations to update the incoming value
// for PHI nodes in common successor.
- if (FoldBranchToCommonDest(BI, BonusInstThreshold))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ if (FoldBranchToCommonDest(BI, Options.BonusInstThreshold))
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
return false;
}
@@ -5755,7 +5754,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(
// switch.
if (BasicBlock *OnlyPred = BB->getSinglePredecessor())
if (SimplifyEqualityComparisonWithOnlyPredecessor(BI, OnlyPred, Builder))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
// This block must be empty, except for the setcond inst, if it exists.
// Ignore dbg intrinsics.
@@ -5765,14 +5764,14 @@ bool SimplifyCFGOpt::SimplifyCondBranch(
++I;
if (&*I == BI) {
if (FoldValueComparisonIntoPredecessors(BI, Builder))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
} else if (&*I == cast<Instruction>(BI->getCondition())) {
++I;
// Ignore dbg intrinsics.
while (isa<DbgInfoIntrinsic>(I))
++I;
if (&*I == BI && FoldValueComparisonIntoPredecessors(BI, Builder))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
}
}
@@ -5799,7 +5798,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(
: ConstantInt::getFalse(BB->getContext());
BI->setCondition(CI);
RecursivelyDeleteTriviallyDeadInstructions(OldCond);
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
}
}
}
@@ -5807,8 +5806,8 @@ bool SimplifyCFGOpt::SimplifyCondBranch(
// If this basic block is ONLY a compare and a branch, and if a predecessor
// branches to us and one of our successors, fold the comparison into the
// predecessor and use logical operations to pick the right destination.
- if (FoldBranchToCommonDest(BI, BonusInstThreshold))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ if (FoldBranchToCommonDest(BI, Options.BonusInstThreshold))
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
// We have a conditional branch to two blocks that are only reachable
// from BI. We know that the condbr dominates the two blocks, so see if
@@ -5817,7 +5816,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(
if (BI->getSuccessor(0)->getSinglePredecessor()) {
if (BI->getSuccessor(1)->getSinglePredecessor()) {
if (HoistThenElseCodeToIf(BI, TTI))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
} else {
// If Successor #1 has multiple preds, we may be able to conditionally
// execute Successor #0 if it branches to Successor #1.
@@ -5825,7 +5824,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(
if (Succ0TI->getNumSuccessors() == 1 &&
Succ0TI->getSuccessor(0) == BI->getSuccessor(1))
if (SpeculativelyExecuteBB(BI, BI->getSuccessor(0), TTI))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
}
} else if (BI->getSuccessor(1)->getSinglePredecessor()) {
// If Successor #0 has multiple preds, we may be able to conditionally
@@ -5834,7 +5833,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(
if (Succ1TI->getNumSuccessors() == 1 &&
Succ1TI->getSuccessor(0) == BI->getSuccessor(0))
if (SpeculativelyExecuteBB(BI, BI->getSuccessor(1), TTI))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
}
// If this is a branch on a phi node in the current block, thread control
@@ -5842,14 +5841,14 @@ bool SimplifyCFGOpt::SimplifyCondBranch(
if (PHINode *PN = dyn_cast<PHINode>(BI->getCondition()))
if (PN->getParent() == BI->getParent())
if (FoldCondBranchOnPHI(BI, DL, AC))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
// Scan predecessor blocks for conditional branches.
for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
if (BranchInst *PBI = dyn_cast<BranchInst>((*PI)->getTerminator()))
if (PBI != BI && PBI->isConditional())
if (SimplifyCondBranchToCondBranch(PBI, BI, DL))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
// Look for diamond patterns.
if (MergeCondStores)
@@ -5857,7 +5856,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(
if (BranchInst *PBI = dyn_cast<BranchInst>(PrevBB->getTerminator()))
if (PBI != BI && PBI->isConditional())
if (mergeConditionalStores(PBI, BI, DL))
- return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
+ return SimplifyCFG(BB, TTI, AC, Options) | true;
return false;
}
@@ -6013,16 +6012,10 @@ bool SimplifyCFGOpt::run(BasicBlock *BB)
return Changed;
}
-/// This function is used to do simplification of a CFG.
-/// For example, it adjusts branches to branches to eliminate the extra hop,
-/// eliminates unreachable basic blocks, and does other "peephole" optimization
-/// of the CFG. It returns true if a modification was made.
-///
bool llvm::SimplifyCFG(BasicBlock *BB, const TargetTransformInfo &TTI,
- unsigned BonusInstThreshold, AssumptionCache *AC,
- SmallPtrSetImpl<BasicBlock *> *LoopHeaders,
- bool LateSimplifyCFG) {
- return SimplifyCFGOpt(TTI, BB->getModule()->getDataLayout(),
- BonusInstThreshold, AC, LoopHeaders, LateSimplifyCFG)
+ AssumptionCache *AC, const SimplifyCFGOptions &Options,
+ SmallPtrSetImpl<BasicBlock *> *LoopHeaders) {
+ return SimplifyCFGOpt(TTI, BB->getModule()->getDataLayout(), AC, LoopHeaders,
+ Options)
.run(BB);
}
Modified: llvm/trunk/test/Transforms/SimplifyCFG/X86/switch_to_lookup_table.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SimplifyCFG/X86/switch_to_lookup_table.ll?rev=314308&r1=314307&r2=314308&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/SimplifyCFG/X86/switch_to_lookup_table.ll (original)
+++ llvm/trunk/test/Transforms/SimplifyCFG/X86/switch_to_lookup_table.ll Wed Sep 27 07:54:16 2017
@@ -1173,10 +1173,10 @@ return:
ret i32 %retval.0
; CHECK-LABEL: @reuse_cmp2(
; CHECK: entry:
-; CHECK-NEXT: %switch = icmp ult i32 %x, 4
-; CHECK-NEXT: %x. = select i1 %switch, i32 %x, i32 4
+; CHECK-NEXT: %0 = icmp ult i32 %x, 4
+; CHECK-NEXT: %x. = select i1 %0, i32 %x, i32 4
; CHECK-NEXT: [[C:%.+]] = icmp ne i32 %x., 4
-; CHECK: [[R:%.+]] = select i1 [[C]], i32 {{.*}}, i32 100
+; CHECK: [[R:%.+]] = select i1 %0, i32 {{.*}}, i32 100
; CHECK-NEXT: ret i32 [[R]]
}
Modified: llvm/trunk/tools/bugpoint/CrashDebugger.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/bugpoint/CrashDebugger.cpp?rev=314308&r1=314307&r2=314308&view=diff
==============================================================================
--- llvm/trunk/tools/bugpoint/CrashDebugger.cpp (original)
+++ llvm/trunk/tools/bugpoint/CrashDebugger.cpp Wed Sep 27 07:54:16 2017
@@ -648,7 +648,7 @@ bool ReduceSimplifyCFG::TestBlocks(std::
++BBIt;
continue;
}
- SimplifyCFG(&*BBIt++, TTI, 1);
+ SimplifyCFG(&*BBIt++, TTI);
}
// Verify we didn't break anything
std::vector<std::string> Passes;
More information about the llvm-commits
mailing list