Summary:
This commits moves skipDebugInstructionsForward and
skipDebugInstructionsBackward from lib/CodeGen/IfConversion.cpp
to include/llvm/CodeGen/MachineBasicBlock.h and updates
some codgen files to use them.
This refactoring was suggested in https://reviews.llvm.org/D27688
and I thought it's best to do the refactoring in a separate
review, but I could also put both changes in a single review
if that's preferred.
Also, the names for the functions aren't the snappiest and
I would be happy to rename them if anybody has suggestions.
Reviewers: eli.friedman, iteratee, aprantl, MatzeB
Subscribers: MatzeB, llvm-commits
Differential Revision: https://reviews.llvm.org/D27782
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289933
91177308-0d34-0410-b5e6-
96231b3b80d8
MachineBasicBlock::iterator getInitial() { return I; }
};
+/// Increment \p It until it points to a non-debug instruction or to \p End
+/// and return the resulting iterator. This function should only be used
+/// MachineBasicBlock::{iterator, const_iterator, instr_iterator,
+/// const_instr_iterator} and the respective reverse iterators.
+template<typename IterT>
+inline IterT skipDebugInstructionsForward(IterT It, IterT End) {
+ while (It != End && It->isDebugValue())
+ It++;
+ return It;
+}
+
+/// Decrement \p It until it points to a non-debug instruction or to \p Begin
+/// and return the resulting iterator. This function should only be used
+/// MachineBasicBlock::{iterator, const_iterator, instr_iterator,
+/// const_instr_iterator} and the respective reverse iterators.
+template<class IterT>
+inline IterT skipDebugInstructionsBackward(IterT It, IterT Begin) {
+ while (It != Begin && It->isDebugValue())
+ It--;
+ return It;
+}
+
} // End llvm namespace
#endif
// The terminator is probably a conditional branch, try not to separate the
// branch from condition setting instruction.
- MachineBasicBlock::iterator PI = Loc;
- --PI;
- while (PI != MBB->begin() && PI->isDebugValue())
- --PI;
+ MachineBasicBlock::iterator PI =
+ skipDebugInstructionsBackward(std::prev(Loc), MBB->begin());
bool IsDef = false;
for (const MachineOperand &MO : PI->operands()) {
MachineBasicBlock::iterator FIE = FBB->end();
while (TIB != TIE && FIB != FIE) {
// Skip dbg_value instructions. These do not count.
- if (TIB->isDebugValue()) {
- while (TIB != TIE && TIB->isDebugValue())
- ++TIB;
- if (TIB == TIE)
- break;
- }
- if (FIB->isDebugValue()) {
- while (FIB != FIE && FIB->isDebugValue())
- ++FIB;
- if (FIB == FIE)
- break;
- }
+ TIB = skipDebugInstructionsForward(TIB, TIE);
+ FIB = skipDebugInstructionsForward(FIB, FIE);
+ if (TIB == TIE || FIB == FIE)
+ break;
+
if (!TIB->isIdenticalTo(*FIB, MachineInstr::CheckKillDead))
break;
return TExit && TExit == FalseBBI.BB;
}
-/// Increment \p It until it points to a non-debug instruction or to \p End.
-/// @param It Iterator to increment
-/// @param End Iterator that points to end. Will be compared to It
-/// @returns true if It == End, false otherwise.
-static inline bool skipDebugInstructionsForward(
- MachineBasicBlock::iterator &It,
- MachineBasicBlock::iterator &End) {
- while (It != End && It->isDebugValue())
- It++;
- return It == End;
-}
-
/// Shrink the provided inclusive range by one instruction.
/// If the range was one instruction (\p It == \p Begin), It is not modified,
/// but \p Empty is set to true.
It--;
}
-/// Decrement \p It until it points to a non-debug instruction or the range is
-/// empty.
-/// @param It Iterator to decrement.
-/// @param Begin Iterator that points to beginning. Will be compared to It
-/// @param Empty Set to true if the resulting range is Empty
-/// @returns the value of Empty as a convenience.
-static inline bool skipDebugInstructionsBackward(
- MachineBasicBlock::iterator &Begin,
- MachineBasicBlock::iterator &It,
- bool &Empty) {
- while (!Empty && It->isDebugValue())
- shrinkInclusiveRange(Begin, It, Empty);
- return Empty;
-}
-
/// Count duplicated instructions and move the iterators to show where they
/// are.
/// @param TIB True Iterator Begin
while (TIB != TIE && FIB != FIE) {
// Skip dbg_value instructions. These do not count.
- if(skipDebugInstructionsForward(TIB, TIE))
+ TIB = skipDebugInstructionsForward(TIB, TIE);
+ if(TIB == TIE)
break;
- if(skipDebugInstructionsForward(FIB, FIE))
+ FIB = skipDebugInstructionsForward(FIB, FIE);
+ if(FIB == FIE)
break;
if (!TIB->isIdenticalTo(*FIB))
break;
// Count duplicate instructions at the ends of the blocks.
while (!TEmpty && !FEmpty) {
// Skip dbg_value instructions. These do not count.
- if (skipDebugInstructionsBackward(TIB, TIE, TEmpty))
- break;
- if (skipDebugInstructionsBackward(FIB, FIE, FEmpty))
+ TIE = skipDebugInstructionsBackward(TIE, TIB);
+ FIE = skipDebugInstructionsBackward(FIE, FIB);
+ TEmpty = TIE == TIB && TIE->isDebugValue();
+ FEmpty = FIE == FIB && FIE->isDebugValue();
+ if (TEmpty || FEmpty)
break;
if (!TIE->isIdenticalTo(*FIE))
break;
MachineBasicBlock::iterator E2 = std::prev(MBB2->end());
bool Empty1 = false, Empty2 = false;
while (!Empty1 && !Empty2) {
- skipDebugInstructionsBackward(B1, E1, Empty1);
- skipDebugInstructionsBackward(B2, E2, Empty2);
+ E1 = skipDebugInstructionsBackward(E1, B1);
+ E2 = skipDebugInstructionsBackward(E2, B2);
+ Empty1 = E1 == B1 && E1->isDebugValue();
+ Empty2 = E2 == B2 && E2->isDebugValue();
+
if (Empty1 && Empty2)
break;
MachineBasicBlock::iterator MachineBasicBlock::getFirstNonDebugInstr() {
// Skip over begin-of-block dbg_value instructions.
- iterator I = begin(), E = end();
- while (I != E && I->isDebugValue())
- ++I;
- return I;
+ return skipDebugInstructionsForward(begin(), end());
}
MachineBasicBlock::iterator MachineBasicBlock::getLastNonDebugInstr() {
/// instructions. Return UnknownLoc if there is none.
DebugLoc
MachineBasicBlock::findDebugLoc(instr_iterator MBBI) {
- DebugLoc DL;
- instr_iterator E = instr_end();
- if (MBBI == E)
- return DL;
-
// Skip debug declarations, we don't want a DebugLoc from them.
- while (MBBI != E && MBBI->isDebugValue())
- MBBI++;
- if (MBBI != E)
- DL = MBBI->getDebugLoc();
- return DL;
+ MBBI = skipDebugInstructionsForward(MBBI, instr_end());
+ if (MBBI != instr_end())
+ return MBBI->getDebugLoc();
+ return {};
}
/// Return probability of the edge from this block to MBB.
unsigned LookAheadLeft = LookAheadLimit;
while (LookAheadLeft) {
// Skip over dbg_value's.
- while (I != E && I->isDebugValue())
- ++I;
+ I = skipDebugInstructionsForward(I, E);
if (I == E)
// Reached end of block, register is obviously dead.
SlotIndex RegPressureTracker::getCurrSlot() const {
- MachineBasicBlock::const_iterator IdxPos = CurrPos;
- while (IdxPos != MBB->end() && IdxPos->isDebugValue())
- ++IdxPos;
+ MachineBasicBlock::const_iterator IdxPos =
+ skipDebugInstructionsForward(CurrPos, MBB->end());
if (IdxPos == MBB->end())
return LIS->getMBBEndIdx(MBB);
return LIS->getInstructionIndex(*IdxPos).getRegSlot();
static_cast<RegionPressure&>(P).openTop(CurrPos);
// Find the previous instruction.
- do
- --CurrPos;
- while (CurrPos != MBB->begin() && CurrPos->isDebugValue());
+ CurrPos = skipDebugInstructionsBackward(std::prev(CurrPos), MBB->begin());
SlotIndex SlotIdx;
if (RequireIntervals)
bumpDeadDefs(RegOpers.DeadDefs);
// Find the next instruction.
- do
- ++CurrPos;
- while (CurrPos != MBB->end() && CurrPos->isDebugValue());
+ CurrPos = skipDebugInstructionsForward(std::next(CurrPos), MBB->end());
}
void RegPressureTracker::advance() {