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-rw-r--r--contrib/llvm-project/llvm/lib/Transforms/IPO/PruneEH.cpp72
1 files changed, 33 insertions, 39 deletions
diff --git a/contrib/llvm-project/llvm/lib/Transforms/IPO/PruneEH.cpp b/contrib/llvm-project/llvm/lib/Transforms/IPO/PruneEH.cpp
index a16dc664db64..3f3b18771cd5 100644
--- a/contrib/llvm-project/llvm/lib/Transforms/IPO/PruneEH.cpp
+++ b/contrib/llvm-project/llvm/lib/Transforms/IPO/PruneEH.cpp
@@ -13,6 +13,7 @@
//
//===----------------------------------------------------------------------===//
+#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/CallGraph.h"
@@ -27,8 +28,10 @@
#include "llvm/InitializePasses.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/IPO.h"
+#include "llvm/Transforms/Utils/CallGraphUpdater.h"
#include "llvm/Transforms/Utils/Local.h"
#include <algorithm>
+
using namespace llvm;
#define DEBUG_TYPE "prune-eh"
@@ -45,11 +48,10 @@ namespace {
// runOnSCC - Analyze the SCC, performing the transformation if possible.
bool runOnSCC(CallGraphSCC &SCC) override;
-
};
}
-static bool SimplifyFunction(Function *F, CallGraph &CG);
-static void DeleteBasicBlock(BasicBlock *BB, CallGraph &CG);
+static bool SimplifyFunction(Function *F, CallGraphUpdater &CGU);
+static void DeleteBasicBlock(BasicBlock *BB, CallGraphUpdater &CGU);
char PruneEH::ID = 0;
INITIALIZE_PASS_BEGIN(PruneEH, "prune-eh",
@@ -60,20 +62,17 @@ INITIALIZE_PASS_END(PruneEH, "prune-eh",
Pass *llvm::createPruneEHPass() { return new PruneEH(); }
-static bool runImpl(CallGraphSCC &SCC, CallGraph &CG) {
- SmallPtrSet<CallGraphNode *, 8> SCCNodes;
+static bool runImpl(CallGraphUpdater &CGU, SetVector<Function *> &Functions) {
+#ifndef NDEBUG
+ for (auto *F : Functions)
+ assert(F && "null Function");
+#endif
bool MadeChange = false;
- // Fill SCCNodes with the elements of the SCC. Used for quickly
- // looking up whether a given CallGraphNode is in this SCC.
- for (CallGraphNode *I : SCC)
- SCCNodes.insert(I);
-
// First pass, scan all of the functions in the SCC, simplifying them
// according to what we know.
- for (CallGraphNode *I : SCC)
- if (Function *F = I->getFunction())
- MadeChange |= SimplifyFunction(F, CG);
+ for (Function *F : Functions)
+ MadeChange |= SimplifyFunction(F, CGU);
// Next, check to see if any callees might throw or if there are any external
// functions in this SCC: if so, we cannot prune any functions in this SCC.
@@ -83,13 +82,8 @@ static bool runImpl(CallGraphSCC &SCC, CallGraph &CG) {
// obviously the SCC might throw.
//
bool SCCMightUnwind = false, SCCMightReturn = false;
- for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end();
- (!SCCMightUnwind || !SCCMightReturn) && I != E; ++I) {
- Function *F = (*I)->getFunction();
- if (!F) {
- SCCMightUnwind = true;
- SCCMightReturn = true;
- } else if (!F->hasExactDefinition()) {
+ for (Function *F : Functions) {
+ if (!F->hasExactDefinition()) {
SCCMightUnwind |= !F->doesNotThrow();
SCCMightReturn |= !F->doesNotReturn();
} else {
@@ -125,10 +119,9 @@ static bool runImpl(CallGraphSCC &SCC, CallGraph &CG) {
bool InstMightUnwind = true;
if (const auto *CI = dyn_cast<CallInst>(&I)) {
if (Function *Callee = CI->getCalledFunction()) {
- CallGraphNode *CalleeNode = CG[Callee];
// If the callee is outside our current SCC then we may throw
// because it might. If it is inside, do nothing.
- if (SCCNodes.count(CalleeNode) > 0)
+ if (Functions.contains(Callee))
InstMightUnwind = false;
}
}
@@ -140,18 +133,15 @@ static bool runImpl(CallGraphSCC &SCC, CallGraph &CG) {
if (IA->hasSideEffects())
SCCMightReturn = true;
}
-
+ }
if (SCCMightUnwind && SCCMightReturn)
break;
- }
}
}
// If the SCC doesn't unwind or doesn't throw, note this fact.
if (!SCCMightUnwind || !SCCMightReturn)
- for (CallGraphNode *I : SCC) {
- Function *F = I->getFunction();
-
+ for (Function *F : Functions) {
if (!SCCMightUnwind && !F->hasFnAttribute(Attribute::NoUnwind)) {
F->addFnAttr(Attribute::NoUnwind);
MadeChange = true;
@@ -163,30 +153,35 @@ static bool runImpl(CallGraphSCC &SCC, CallGraph &CG) {
}
}
- for (CallGraphNode *I : SCC) {
+ for (Function *F : Functions) {
// Convert any invoke instructions to non-throwing functions in this node
// into call instructions with a branch. This makes the exception blocks
// dead.
- if (Function *F = I->getFunction())
- MadeChange |= SimplifyFunction(F, CG);
+ MadeChange |= SimplifyFunction(F, CGU);
}
return MadeChange;
}
-
bool PruneEH::runOnSCC(CallGraphSCC &SCC) {
if (skipSCC(SCC))
return false;
+ SetVector<Function *> Functions;
+ for (auto &N : SCC) {
+ if (auto *F = N->getFunction())
+ Functions.insert(F);
+ }
CallGraph &CG = getAnalysis<CallGraphWrapperPass>().getCallGraph();
- return runImpl(SCC, CG);
+ CallGraphUpdater CGU;
+ CGU.initialize(CG, SCC);
+ return runImpl(CGU, Functions);
}
// SimplifyFunction - Given information about callees, simplify the specified
// function if we have invokes to non-unwinding functions or code after calls to
// no-return functions.
-static bool SimplifyFunction(Function *F, CallGraph &CG) {
+static bool SimplifyFunction(Function *F, CallGraphUpdater &CGU) {
bool MadeChange = false;
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
if (InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator()))
@@ -196,7 +191,7 @@ static bool SimplifyFunction(Function *F, CallGraph &CG) {
// If the unwind block is now dead, nuke it.
if (pred_empty(UnwindBlock))
- DeleteBasicBlock(UnwindBlock, CG); // Delete the new BB.
+ DeleteBasicBlock(UnwindBlock, CGU); // Delete the new BB.
++NumRemoved;
MadeChange = true;
@@ -216,7 +211,7 @@ static bool SimplifyFunction(Function *F, CallGraph &CG) {
BB->getInstList().pop_back();
new UnreachableInst(BB->getContext(), &*BB);
- DeleteBasicBlock(New, CG); // Delete the new BB.
+ DeleteBasicBlock(New, CGU); // Delete the new BB.
MadeChange = true;
++NumUnreach;
break;
@@ -229,12 +224,11 @@ static bool SimplifyFunction(Function *F, CallGraph &CG) {
/// DeleteBasicBlock - remove the specified basic block from the program,
/// updating the callgraph to reflect any now-obsolete edges due to calls that
/// exist in the BB.
-static void DeleteBasicBlock(BasicBlock *BB, CallGraph &CG) {
+static void DeleteBasicBlock(BasicBlock *BB, CallGraphUpdater &CGU) {
assert(pred_empty(BB) && "BB is not dead!");
Instruction *TokenInst = nullptr;
- CallGraphNode *CGN = CG[BB->getParent()];
for (BasicBlock::iterator I = BB->end(), E = BB->begin(); I != E; ) {
--I;
@@ -246,9 +240,9 @@ static void DeleteBasicBlock(BasicBlock *BB, CallGraph &CG) {
if (auto *Call = dyn_cast<CallBase>(&*I)) {
const Function *Callee = Call->getCalledFunction();
if (!Callee || !Intrinsic::isLeaf(Callee->getIntrinsicID()))
- CGN->removeCallEdgeFor(*Call);
+ CGU.removeCallSite(*Call);
else if (!Callee->isIntrinsic())
- CGN->removeCallEdgeFor(*Call);
+ CGU.removeCallSite(*Call);
}
if (!I->use_empty())