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-rw-r--r--lib/Transforms/Scalar/SimplifyCFGPass.cpp161
1 files changed, 85 insertions, 76 deletions
diff --git a/lib/Transforms/Scalar/SimplifyCFGPass.cpp b/lib/Transforms/Scalar/SimplifyCFGPass.cpp
index 8754c714c5b2..1522170dc3b9 100644
--- a/lib/Transforms/Scalar/SimplifyCFGPass.cpp
+++ b/lib/Transforms/Scalar/SimplifyCFGPass.cpp
@@ -45,9 +45,26 @@ using namespace llvm;
#define DEBUG_TYPE "simplifycfg"
-static cl::opt<unsigned>
-UserBonusInstThreshold("bonus-inst-threshold", cl::Hidden, cl::init(1),
- cl::desc("Control the number of bonus instructions (default = 1)"));
+static cl::opt<unsigned> UserBonusInstThreshold(
+ "bonus-inst-threshold", cl::Hidden, cl::init(1),
+ cl::desc("Control the number of bonus instructions (default = 1)"));
+
+static cl::opt<bool> UserKeepLoops(
+ "keep-loops", cl::Hidden, cl::init(true),
+ cl::desc("Preserve canonical loop structure (default = true)"));
+
+static cl::opt<bool> UserSwitchToLookup(
+ "switch-to-lookup", cl::Hidden, cl::init(false),
+ cl::desc("Convert switches to lookup tables (default = false)"));
+
+static cl::opt<bool> UserForwardSwitchCond(
+ "forward-switch-cond", cl::Hidden, cl::init(false),
+ cl::desc("Forward switch condition to phi ops (default = false)"));
+
+static cl::opt<bool> UserSinkCommonInsts(
+ "sink-common-insts", cl::Hidden, cl::init(false),
+ cl::desc("Sink common instructions (default = false)"));
+
STATISTIC(NumSimpl, "Number of blocks simplified");
@@ -129,9 +146,7 @@ static bool mergeEmptyReturnBlocks(Function &F) {
/// Call SimplifyCFG on all the blocks in the function,
/// 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 +161,7 @@ static bool iterativelySimplifyCFG(Function &F, const TargetTransformInfo &TTI,
// 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, Options, &LoopHeaders)) {
LocalChange = true;
++NumSimpl;
}
@@ -157,12 +172,10 @@ static bool iterativelySimplifyCFG(Function &F, const TargetTransformInfo &TTI,
}
static bool simplifyFunctionCFG(Function &F, const TargetTransformInfo &TTI,
- AssumptionCache *AC, int BonusInstThreshold,
- bool LateSimplifyCFG) {
+ const SimplifyCFGOptions &Options) {
bool EverChanged = removeUnreachableBlocks(F);
EverChanged |= mergeEmptyReturnBlocks(F);
- EverChanged |= iterativelySimplifyCFG(F, TTI, AC, BonusInstThreshold,
- LateSimplifyCFG);
+ EverChanged |= iterativelySimplifyCFG(F, TTI, Options);
// If neither pass changed anything, we're done.
if (!EverChanged) return false;
@@ -176,28 +189,37 @@ static bool simplifyFunctionCFG(Function &F, const TargetTransformInfo &TTI,
return true;
do {
- EverChanged = iterativelySimplifyCFG(F, TTI, AC, BonusInstThreshold,
- LateSimplifyCFG);
+ EverChanged = iterativelySimplifyCFG(F, TTI, Options);
EverChanged |= removeUnreachableBlocks(F);
} while (EverChanged);
return true;
}
-SimplifyCFGPass::SimplifyCFGPass()
- : BonusInstThreshold(UserBonusInstThreshold),
- LateSimplifyCFG(true) {}
-
-SimplifyCFGPass::SimplifyCFGPass(int BonusInstThreshold, bool LateSimplifyCFG)
- : BonusInstThreshold(BonusInstThreshold),
- LateSimplifyCFG(LateSimplifyCFG) {}
+// Command-line settings override compile-time settings.
+SimplifyCFGPass::SimplifyCFGPass(const SimplifyCFGOptions &Opts) {
+ Options.BonusInstThreshold = UserBonusInstThreshold.getNumOccurrences()
+ ? UserBonusInstThreshold
+ : Opts.BonusInstThreshold;
+ Options.ForwardSwitchCondToPhi = UserForwardSwitchCond.getNumOccurrences()
+ ? UserForwardSwitchCond
+ : Opts.ForwardSwitchCondToPhi;
+ Options.ConvertSwitchToLookupTable = UserSwitchToLookup.getNumOccurrences()
+ ? UserSwitchToLookup
+ : Opts.ConvertSwitchToLookupTable;
+ Options.NeedCanonicalLoop = UserKeepLoops.getNumOccurrences()
+ ? UserKeepLoops
+ : Opts.NeedCanonicalLoop;
+ Options.SinkCommonInsts = UserSinkCommonInsts.getNumOccurrences()
+ ? UserSinkCommonInsts
+ : Opts.SinkCommonInsts;
+}
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))
+ Options.AC = &AM.getResult<AssumptionAnalysis>(F);
+ if (!simplifyFunctionCFG(F, TTI, Options))
return PreservedAnalyses::all();
PreservedAnalyses PA;
PA.preserve<GlobalsAA>();
@@ -205,55 +227,54 @@ PreservedAnalyses SimplifyCFGPass::run(Function &F,
}
namespace {
-struct BaseCFGSimplifyPass : public FunctionPass {
- unsigned BonusInstThreshold;
+struct CFGSimplifyPass : public FunctionPass {
+ static char ID;
+ SimplifyCFGOptions Options;
std::function<bool(const Function &)> PredicateFtor;
- bool LateSimplifyCFG;
-
- BaseCFGSimplifyPass(int T, bool LateSimplifyCFG,
- std::function<bool(const Function &)> Ftor,
- char &ID)
- : FunctionPass(ID), PredicateFtor(std::move(Ftor)),
- LateSimplifyCFG(LateSimplifyCFG) {
- BonusInstThreshold = (T == -1) ? UserBonusInstThreshold : unsigned(T);
+
+ CFGSimplifyPass(unsigned Threshold = 1, bool ForwardSwitchCond = false,
+ bool ConvertSwitch = false, bool KeepLoops = true,
+ bool SinkCommon = false,
+ std::function<bool(const Function &)> Ftor = nullptr)
+ : FunctionPass(ID), PredicateFtor(std::move(Ftor)) {
+
+ initializeCFGSimplifyPassPass(*PassRegistry::getPassRegistry());
+
+ // Check for command-line overrides of options for debug/customization.
+ Options.BonusInstThreshold = UserBonusInstThreshold.getNumOccurrences()
+ ? UserBonusInstThreshold
+ : Threshold;
+
+ Options.ForwardSwitchCondToPhi = UserForwardSwitchCond.getNumOccurrences()
+ ? UserForwardSwitchCond
+ : ForwardSwitchCond;
+
+ Options.ConvertSwitchToLookupTable = UserSwitchToLookup.getNumOccurrences()
+ ? UserSwitchToLookup
+ : ConvertSwitch;
+
+ Options.NeedCanonicalLoop =
+ UserKeepLoops.getNumOccurrences() ? UserKeepLoops : KeepLoops;
+
+ Options.SinkCommonInsts = UserSinkCommonInsts.getNumOccurrences()
+ ? UserSinkCommonInsts
+ : SinkCommon;
}
+
bool runOnFunction(Function &F) override {
if (skipFunction(F) || (PredicateFtor && !PredicateFtor(F)))
return false;
- AssumptionCache *AC =
- &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
- const TargetTransformInfo &TTI =
- getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
- return simplifyFunctionCFG(F, TTI, AC, BonusInstThreshold, LateSimplifyCFG);
+ Options.AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
+ auto &TTI = getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
+ return simplifyFunctionCFG(F, TTI, Options);
}
-
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<AssumptionCacheTracker>();
AU.addRequired<TargetTransformInfoWrapperPass>();
AU.addPreserved<GlobalsAAWrapperPass>();
}
};
-
-struct CFGSimplifyPass : public BaseCFGSimplifyPass {
- static char ID; // Pass identification, replacement for typeid
-
- CFGSimplifyPass(int T = -1,
- std::function<bool(const Function &)> Ftor = nullptr)
- : BaseCFGSimplifyPass(T, false, Ftor, ID) {
- initializeCFGSimplifyPassPass(*PassRegistry::getPassRegistry());
- }
-};
-
-struct LateCFGSimplifyPass : public BaseCFGSimplifyPass {
- static char ID; // Pass identification, replacement for typeid
-
- LateCFGSimplifyPass(int T = -1,
- std::function<bool(const Function &)> Ftor = nullptr)
- : BaseCFGSimplifyPass(T, true, Ftor, ID) {
- initializeLateCFGSimplifyPassPass(*PassRegistry::getPassRegistry());
- }
-};
}
char CFGSimplifyPass::ID = 0;
@@ -264,24 +285,12 @@ INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
INITIALIZE_PASS_END(CFGSimplifyPass, "simplifycfg", "Simplify the CFG", false,
false)
-char LateCFGSimplifyPass::ID = 0;
-INITIALIZE_PASS_BEGIN(LateCFGSimplifyPass, "latesimplifycfg",
- "Simplify the CFG more aggressively", false, false)
-INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
-INITIALIZE_PASS_END(LateCFGSimplifyPass, "latesimplifycfg",
- "Simplify the CFG more aggressively", false, false)
-
// Public interface to the CFGSimplification pass
FunctionPass *
-llvm::createCFGSimplificationPass(int Threshold,
- std::function<bool(const Function &)> Ftor) {
- return new CFGSimplifyPass(Threshold, std::move(Ftor));
-}
-
-// Public interface to the LateCFGSimplification pass
-FunctionPass *
-llvm::createLateCFGSimplificationPass(int Threshold,
+llvm::createCFGSimplificationPass(unsigned Threshold, bool ForwardSwitchCond,
+ bool ConvertSwitch, bool KeepLoops,
+ bool SinkCommon,
std::function<bool(const Function &)> Ftor) {
- return new LateCFGSimplifyPass(Threshold, std::move(Ftor));
+ return new CFGSimplifyPass(Threshold, ForwardSwitchCond, ConvertSwitch,
+ KeepLoops, SinkCommon, std::move(Ftor));
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-07 22:27:56 +0000