averello/swift-mirror
1
0
Fork 0
mirror of https://github.com/apple/swift.git synced 2025-12-21 12:14:44 +01:00
Code Issues Packages Projects Releases Wiki Activity

[g-arc-opts] Wired up the Release->RetainState (TDMap), Retain->ReleaseState (BUMap) dataflow into the pair matcher analysis which matches up sets of retains, releases.

Browse Source 
This completes the implementation of the bottom up decrement data flow
data analysis.

<rdar://problem/16965332>

Swift SVN r18580
This commit is contained in:
Michael Gottesman
2014-05-23 01:34:13 +00:00
parent 2d004856cf
commit 445c474ed0
6 changed files with 380 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files

36
lib/SILAnalysis/GlobalARCSequenceDataflow.cpp
View File

@@ -206,24 +206,27 @@ processBBTopDown(ARCBBState &BBState,
continue;
}
SILValue Op;
// If I is a ref count increment instruction...
if (isRefCountIncrement(I)) {
// map its operand to a newly initialized or reinitialized ref count
// state and continue...
SILValue Op = I.getOperand(0).stripCasts();
Op = I.getOperand(0).stripCasts();
TopDownRefCountState &State = BBState.getTopDownRefCountState(Op);
NestingDetected |= State.initWithInst(&I);
DEBUG(llvm::dbgs() << " REF COUNT INCREMENT! Known Safe: "
<< (State.isKnownSafe()?"yes":"no") << "\n");
continue;
// Continue processing in case this increment could be a CanUse for a
// different pointer.
}
// If we have a reference count decrement...
if (isRefCountDecrement(I)) {
// Look up the state associated with its operand...
SILValue Op = I.getOperand(0).stripCasts();
Op = I.getOperand(0).stripCasts();
TopDownRefCountState &RefCountState = BBState.getTopDownRefCountState(Op);
DEBUG(llvm::dbgs() << " REF COUNT DECREMENT!\n");
@@ -258,6 +261,10 @@ processBBTopDown(ARCBBState &BBState,
// For all other (reference counted value, ref count state) we are
// tracking...
for (auto &OtherState : BBState.getTopDownStates()) {
// If the state we are visiting is for the pointer we just visited, bail.
if (Op && OtherState.first == Op)
continue;
// If we are tracking an argument, skip it.
if (!OtherState.second.isTrackingRefCountInst())
continue;
@@ -326,26 +333,29 @@ processBBBottomUp(ARCBBState &BBState,
continue;
}
SILValue Op;
// If I is a ref count decrement instruction...
if (isRefCountDecrement(I)) {
// map its operand to a newly initialized or reinitialized ref count
// state and continue...
SILValue Op = I.getOperand(0).stripCasts();
Op = I.getOperand(0).stripCasts();
BottomUpRefCountState &State = BBState.getBottomUpRefCountState(Op);
NestingDetected |= State.initWithInst(&I);
DEBUG(llvm::dbgs() << " REF COUNT DECREMENT! Known Safe: "
<< (State.isKnownSafe()?"yes":"no") << "\n");
continue;
// Continue on to see if our reference decrement could potentially affect
// any other pointers via a use or a decrement.
}
// If we have a reference count decrement...
if (isRefCountIncrement(I)) {
// Look up the state associated with its operand...
SILValue Op = I.getOperand(0).stripCasts();
Op = I.getOperand(0).stripCasts();
BottomUpRefCountState &RefCountState =
BBState.getBottomUpRefCountState(Op);
BBState.getBottomUpRefCountState(Op);
DEBUG(llvm::dbgs() << " REF COUNT INCREMENT!\n");
@@ -355,7 +365,7 @@ processBBBottomUp(ARCBBState &BBState,
// and add the retain/release pair to the delete list and continue.
if (RefCountState.isRefCountInstMatchedToTrackedInstruction(&I)) {
// Copy the current value of ref count state into the result map.
IncToDecStateMap[&I] = BottomUpRefCountState(RefCountState);
IncToDecStateMap[&I] = RefCountState;
DEBUG(llvm::dbgs() << " MATCHING DECREMENT:"
<< *RefCountState.getInstruction());
@@ -373,13 +383,17 @@ processBBBottomUp(ARCBBState &BBState,
}
// Otherwise we continue processing the reference count decrement to
// see if the decrement can affect any other pointers that we are
// tracking.
// see if the increment can act as a use for other values.
}
// For all other (reference counted value, ref count state) we are
// tracking...
for (auto &OtherState : BBState.getTopDownStates()) {
for (auto &OtherState : BBState.getBottomupStates()) {
// If this is the state associated with the instruction that we are
// currently visiting, bail.
if (Op && OtherState.first == Op)
continue;
// If we are tracking an argument, skip it.
if (!OtherState.second.isTrackingRefCountInst())
continue;