diff options
author | Chandler Carruth <chandlerc@gmail.com> | 2014-03-09 03:16:01 +0000 |
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committer | Chandler Carruth <chandlerc@gmail.com> | 2014-03-09 03:16:01 +0000 |
commit | 36b699f2b139a30a2dfa4448223d6985b55daa8a (patch) | |
tree | d6844c991f0c06de4b66a2615259607d8349e5b3 /lib/Transforms/Scalar/SROA.cpp | |
parent | b033b03c23fb3ae066937b2ec09eb9d7a3f1d522 (diff) |
[C++11] Add range based accessors for the Use-Def chain of a Value.
This requires a number of steps.
1) Move value_use_iterator into the Value class as an implementation
detail
2) Change it to actually be a *Use* iterator rather than a *User*
iterator.
3) Add an adaptor which is a User iterator that always looks through the
Use to the User.
4) Wrap these in Value::use_iterator and Value::user_iterator typedefs.
5) Add the range adaptors as Value::uses() and Value::users().
6) Update *all* of the callers to correctly distinguish between whether
they wanted a use_iterator (and to explicitly dig out the User when
needed), or a user_iterator which makes the Use itself totally
opaque.
Because #6 requires churning essentially everything that walked the
Use-Def chains, I went ahead and added all of the range adaptors and
switched them to range-based loops where appropriate. Also because the
renaming requires at least churning every line of code, it didn't make
any sense to split these up into multiple commits -- all of which would
touch all of the same lies of code.
The result is still not quite optimal. The Value::use_iterator is a nice
regular iterator, but Value::user_iterator is an iterator over User*s
rather than over the User objects themselves. As a consequence, it fits
a bit awkwardly into the range-based world and it has the weird
extra-dereferencing 'operator->' that so many of our iterators have.
I think this could be fixed by providing something which transforms
a range of T&s into a range of T*s, but that *can* be separated into
another patch, and it isn't yet 100% clear whether this is the right
move.
However, this change gets us most of the benefit and cleans up
a substantial amount of code around Use and User. =]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203364 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Transforms/Scalar/SROA.cpp')
-rw-r--r-- | lib/Transforms/Scalar/SROA.cpp | 45 |
1 files changed, 19 insertions, 26 deletions
diff --git a/lib/Transforms/Scalar/SROA.cpp b/lib/Transforms/Scalar/SROA.cpp index b195ffc86bb..ed5e61823e4 100644 --- a/lib/Transforms/Scalar/SROA.cpp +++ b/lib/Transforms/Scalar/SROA.cpp @@ -637,10 +637,9 @@ private: return I; } - for (Value::use_iterator UI = I->use_begin(), UE = I->use_end(); UI != UE; - ++UI) - if (Visited.insert(cast<Instruction>(*UI))) - Uses.push_back(std::make_pair(I, cast<Instruction>(*UI))); + for (User *U : I->users()) + if (Visited.insert(cast<Instruction>(U))) + Uses.push_back(std::make_pair(I, cast<Instruction>(U))); } while (!Uses.empty()); return 0; @@ -817,12 +816,10 @@ public: // Retain the debug information attached to the alloca for use when // rewriting loads and stores. if (MDNode *DebugNode = MDNode::getIfExists(AI.getContext(), &AI)) { - for (Value::use_iterator UI = DebugNode->use_begin(), - UE = DebugNode->use_end(); - UI != UE; ++UI) - if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(*UI)) + for (User *U : DebugNode->users()) + if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(U)) DDIs.push_back(DDI); - else if (DbgValueInst *DVI = dyn_cast<DbgValueInst>(*UI)) + else if (DbgValueInst *DVI = dyn_cast<DbgValueInst>(U)) DVIs.push_back(DVI); } @@ -1085,9 +1082,8 @@ static bool isSafePHIToSpeculate(PHINode &PN, BasicBlock *BB = PN.getParent(); unsigned MaxAlign = 0; bool HaveLoad = false; - for (Value::use_iterator UI = PN.use_begin(), UE = PN.use_end(); UI != UE; - ++UI) { - LoadInst *LI = dyn_cast<LoadInst>(*UI); + for (User *U : PN.users()) { + LoadInst *LI = dyn_cast<LoadInst>(U); if (LI == 0 || !LI->isSimple()) return false; @@ -1151,13 +1147,13 @@ static void speculatePHINodeLoads(PHINode &PN) { // Get the TBAA tag and alignment to use from one of the loads. It doesn't // matter which one we get and if any differ. - LoadInst *SomeLoad = cast<LoadInst>(*PN.use_begin()); + LoadInst *SomeLoad = cast<LoadInst>(PN.user_back()); MDNode *TBAATag = SomeLoad->getMetadata(LLVMContext::MD_tbaa); unsigned Align = SomeLoad->getAlignment(); // Rewrite all loads of the PN to use the new PHI. while (!PN.use_empty()) { - LoadInst *LI = cast<LoadInst>(*PN.use_begin()); + LoadInst *LI = cast<LoadInst>(PN.user_back()); LI->replaceAllUsesWith(NewPN); LI->eraseFromParent(); } @@ -1201,9 +1197,8 @@ static bool isSafeSelectToSpeculate(SelectInst &SI, const DataLayout *DL = 0) { bool TDerefable = TValue->isDereferenceablePointer(); bool FDerefable = FValue->isDereferenceablePointer(); - for (Value::use_iterator UI = SI.use_begin(), UE = SI.use_end(); UI != UE; - ++UI) { - LoadInst *LI = dyn_cast<LoadInst>(*UI); + for (User *U : SI.users()) { + LoadInst *LI = dyn_cast<LoadInst>(U); if (LI == 0 || !LI->isSimple()) return false; @@ -1229,7 +1224,7 @@ static void speculateSelectInstLoads(SelectInst &SI) { Value *FV = SI.getFalseValue(); // Replace the loads of the select with a select of two loads. while (!SI.use_empty()) { - LoadInst *LI = cast<LoadInst>(*SI.use_begin()); + LoadInst *LI = cast<LoadInst>(SI.user_back()); assert(LI->isSimple() && "We only speculate simple loads"); IRB.SetInsertPoint(LI); @@ -2782,10 +2777,9 @@ private: /// Enqueue all the users of the given instruction for further processing. /// This uses a set to de-duplicate users. void enqueueUsers(Instruction &I) { - for (Value::use_iterator UI = I.use_begin(), UE = I.use_end(); UI != UE; - ++UI) - if (Visited.insert(*UI)) - Queue.push_back(&UI.getUse()); + for (Use &U : I.uses()) + if (Visited.insert(U.getUser())) + Queue.push_back(&U); } // Conservative default is to not rewrite anything. @@ -3516,10 +3510,9 @@ void SROA::deleteDeadInstructions(SmallPtrSet<AllocaInst*, 4> &DeletedAllocas) { static void enqueueUsersInWorklist(Instruction &I, SmallVectorImpl<Instruction *> &Worklist, SmallPtrSet<Instruction *, 8> &Visited) { - for (Value::use_iterator UI = I.use_begin(), UE = I.use_end(); UI != UE; - ++UI) - if (Visited.insert(cast<Instruction>(*UI))) - Worklist.push_back(cast<Instruction>(*UI)); + for (User *U : I.users()) + if (Visited.insert(cast<Instruction>(U))) + Worklist.push_back(cast<Instruction>(U)); } /// \brief Promote the allocas, using the best available technique. |