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[InstCombine] Merge two functions; NFC 

Merge AddReachableCodeToWorklist() into prepareICWorklistFromFunction().
It's one logical step, and this makes it easier to move code.
This commit is contained in:
Nikita Popov 2020-03-28 21:13:33 +01:00
parent d3b6e1f1f9
commit 97cc1275c7
1 changed files with 8 additions and 28 deletions
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36
llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
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@ -3596,27 +3596,27 @@ bool InstCombiner::run() {
return MadeIRChange;
}
/// Walk the function in depth-first order, adding all reachable code to the
/// worklist.
/// Populate the IC worklist from a function, by walking it in depth-first
/// order and adding all reachable code to the worklist.
///
/// This has a couple of tricks to make the code faster and more powerful. In
/// particular, we constant fold and DCE instructions as we go, to avoid adding
/// them to the worklist (this significantly speeds up instcombine on code where
/// many instructions are dead or constant). Additionally, if we find a branch
/// whose condition is a known constant, we only visit the reachable successors.
static bool AddReachableCodeToWorklist(BasicBlock *BB, const DataLayout &DL,
SmallPtrSetImpl<BasicBlock *> &Visited,
InstCombineWorklist &ICWorklist,
const TargetLibraryInfo *TLI) {
static bool prepareICWorklistFromFunction(Function &F, const DataLayout &DL,
const TargetLibraryInfo *TLI,
InstCombineWorklist &ICWorklist) {
bool MadeIRChange = false;
SmallPtrSet<BasicBlock *, 32> Visited;
SmallVector<BasicBlock*, 256> Worklist;
Worklist.push_back(BB);
Worklist.push_back(&F.front());
SmallVector<Instruction*, 128> InstrsForInstCombineWorklist;
DenseMap<Constant *, Constant *> FoldedConstants;
do {
BB = Worklist.pop_back_val();
BasicBlock *BB = Worklist.pop_back_val();
// We have now visited this block! If we've already been here, ignore it.
if (!Visited.insert(BB).second)
@ -3706,26 +3706,6 @@ static bool AddReachableCodeToWorklist(BasicBlock *BB, const DataLayout &DL,
ICWorklist.push(Inst);
}
return MadeIRChange;
}
/// Populate the IC worklist from a function, and prune any dead basic
/// blocks discovered in the process.
///
/// This also does basic constant propagation and other forward fixing to make
/// the combiner itself run much faster.
static bool prepareICWorklistFromFunction(Function &F, const DataLayout &DL,
TargetLibraryInfo *TLI,
InstCombineWorklist &ICWorklist) {
bool MadeIRChange = false;
// Do a depth-first traversal of the function, populate the worklist with
// the reachable instructions. Ignore blocks that are not reachable. Keep
// track of which blocks we visit.
SmallPtrSet<BasicBlock *, 32> Visited;
MadeIRChange |=
AddReachableCodeToWorklist(&F.front(), DL, Visited, ICWorklist, TLI);
// Do a quick scan over the function. If we find any blocks that are
// unreachable, remove any instructions inside of them. This prevents
// the instcombine code from having to deal with some bad special cases.