From cdf4788401afff02e12279fc1fded94d6180639c Mon Sep 17 00:00:00 2001 From: Chandler Carruth Date: Sun, 9 Mar 2014 03:16:01 +0000 Subject: [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. =] llvm-svn: 203364 --- llvm/lib/Analysis/CaptureTracking.cpp | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) (limited to 'llvm/lib/Analysis/CaptureTracking.cpp') diff --git a/llvm/lib/Analysis/CaptureTracking.cpp b/llvm/lib/Analysis/CaptureTracking.cpp index 60978470d2b..3708e6080f3 100644 --- a/llvm/lib/Analysis/CaptureTracking.cpp +++ b/llvm/lib/Analysis/CaptureTracking.cpp @@ -85,17 +85,15 @@ void llvm::PointerMayBeCaptured(const Value *V, CaptureTracker *Tracker) { SmallSet Visited; int Count = 0; - for (Value::const_use_iterator UI = V->use_begin(), UE = V->use_end(); - UI != UE; ++UI) { + for (const Use &U : V->uses()) { // If there are lots of uses, conservatively say that the value // is captured to avoid taking too much compile time. if (Count++ >= Threshold) return Tracker->tooManyUses(); - Use *U = &UI.getUse(); - if (!Tracker->shouldExplore(U)) continue; - Visited.insert(U); - Worklist.push_back(U); + if (!Tracker->shouldExplore(&U)) continue; + Visited.insert(&U); + Worklist.push_back(&U); } while (!Worklist.empty()) { @@ -148,17 +146,15 @@ void llvm::PointerMayBeCaptured(const Value *V, CaptureTracker *Tracker) { case Instruction::AddrSpaceCast: // The original value is not captured via this if the new value isn't. Count = 0; - for (Instruction::use_iterator UI = I->use_begin(), UE = I->use_end(); - UI != UE; ++UI) { + for (Use &UU : I->uses()) { // If there are lots of uses, conservatively say that the value // is captured to avoid taking too much compile time. if (Count++ >= Threshold) return Tracker->tooManyUses(); - Use *U = &UI.getUse(); - if (Visited.insert(U)) - if (Tracker->shouldExplore(U)) - Worklist.push_back(U); + if (Visited.insert(&UU)) + if (Tracker->shouldExplore(&UU)) + Worklist.push_back(&UU); } break; case Instruction::ICmp: -- cgit v1.2.3