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* Transforms: Canonicalize access to function attributes, NFCDuncan P. N. Exon Smith2015-02-141-3/+1
| | | | | | | | | | | | Canonicalize access to function attributes to use the simpler API. getAttributes().getAttribute(AttributeSet::FunctionIndex, Kind) => getFnAttribute(Kind) getAttributes().hasAttribute(AttributeSet::FunctionIndex, Kind) => hasFnAttribute(Kind) llvm-svn: 229202
* [multiversion] Thread a function argument through all the callers of theChandler Carruth2015-02-011-1/+2
| | | | | | | | | | | | | | getTTI method used to get an actual TTI object. No functionality changed. This just threads the argument and ensures code like the inliner can correctly look up the callee's TTI rather than using a fixed one. The next change will use this to implement per-function subtarget usage by TTI. The changes after that should eliminate the need for FTTI as that will have become the default. llvm-svn: 227730
* [PM] Change the core design of the TTI analysis to use a polymorphicChandler Carruth2015-01-311-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
* Teach SplitBlockPredecessors how to handle landingpad blocks.Philip Reames2015-01-281-10/+3
| | | | | | | | | | Patch by: Igor Laevsky <igor@azulsystems.com> "Currently SplitBlockPredecessors generates incorrect code in case if basic block we are going to split has a landingpad. Also seems like it is fairly common case among it's users to conditionally call either SplitBlockPredecessors or SplitLandingPadPredecessors. Because of this I think it is reasonable to add this condition directly into SplitBlockPredecessors." Differential Revision: http://reviews.llvm.org/D7157 llvm-svn: 227390
* [PM] Replace the Pass argument to SplitEdge with specific analyses usedChandler Carruth2015-01-191-3/+3
| | | | | | | | | | | | | | | and updated. This may appear to remove handling for things like alias analysis when splitting critical edges here, but in fact no callers of SplitEdge relied on this. Similarly, all of them wanted to preserve LCSSA if there was any update of the loop info. That makes the interface much simpler. With this, all of BasicBlockUtils.h is free of Pass arguments and prepared for the new pass manager. This is tho majority of utilities that relied on pass arguments. llvm-svn: 226459
* [PM] Cleanup a dead option to critical edge splitting that I noticedChandler Carruth2015-01-191-3/+1
| | | | | | | | | while refactoring this API for the new pass manager. No functionality changed here, the code didn't actually support this option. llvm-svn: 226457
* [PM] Remove the Pass argument from all of the critical edge splittingChandler Carruth2015-01-191-2/+5
| | | | | | | | | | | | | | | | | | | APIs and replace it and numerous booleans with an option struct. The critical edge splitting API has a really large surface of flags and so it seems worth burning a small option struct / builder. This struct can be constructed with the various preserved analyses and then flags can be flipped in a builder style. The various users are now responsible for directly passing along their analysis information. This should be enough for the critical edge splitting to work cleanly with the new pass manager as well. This API is still pretty crufty and could be cleaned up a lot, but I've focused on this change just threading an option struct rather than a pass through the API. llvm-svn: 226456
* [PM] Lift the analyses into the interface forChandler Carruth2015-01-191-1/+2
| | | | | | | | | | SplitLandingPadPredecessors and remove the Pass argument from its interface. Another step to the utilities being usable with both old and new pass managers. llvm-svn: 226426
* [PM] Pull the analyses used for another utility routine into its APIChandler Carruth2015-01-181-1/+3
| | | | | | | | | | | rather than relying on the pass object. This one is a bit annoying, but will pay off. First, supporting this one will make the next one much easier, and for utilities like LoopSimplify, this is moving them (slowly) closer to not having to pass the pass object around throughout their APIs. llvm-svn: 226396
* [PM] Sink the specific analyses preserved by SplitBlock into itsChandler Carruth2015-01-181-1/+1
| | | | | | | | | interface, removing Pass from its interface. This also makes those analyses optional so that passes which don't even preserve these (or use them) can skip the logic entirely. llvm-svn: 226394
* [PM] Now that LoopInfo isn't in the Pass type hierarchy, it is muchChandler Carruth2015-01-181-3/+3
| | | | | | | | | | | | cleaner to derive from the generic base. Thise removes a ton of boiler plate code and somewhat strange and pointless indirections. It also remove a bunch of the previously needed friend declarations. To fully remove these, I also lifted the verify logic into the generic LoopInfoBase, which seems good anyways -- it is generic and useful logic even for the machine side. llvm-svn: 226385
* [PM] Split the LoopInfo object apart from the legacy pass, creatingChandler Carruth2015-01-171-4/+4
| | | | | | | | | | a LoopInfoWrapperPass to wire the object up to the legacy pass manager. This switches all the clients of LoopInfo over and paves the way to port LoopInfo to the new pass manager. No functionality change is intended with this iteration. llvm-svn: 226373
* [PM] Split the AssumptionTracker immutable pass into two separate APIs:Chandler Carruth2015-01-041-10/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | a cache of assumptions for a single function, and an immutable pass that manages those caches. The motivation for this change is two fold. Immutable analyses are really hacks around the current pass manager design and don't exist in the new design. This is usually OK, but it requires that the core logic of an immutable pass be reasonably partitioned off from the pass logic. This change does precisely that. As a consequence it also paves the way for the *many* utility functions that deal in the assumptions to live in both pass manager worlds by creating an separate non-pass object with its own independent API that they all rely on. Now, the only bits of the system that deal with the actual pass mechanics are those that actually need to deal with the pass mechanics. Once this separation is made, several simplifications become pretty obvious in the assumption cache itself. Rather than using a set and callback value handles, it can just be a vector of weak value handles. The callers can easily skip the handles that are null, and eventually we can wrap all of this up behind a filter iterator. For now, this adds boiler plate to the various passes, but this kind of boiler plate will end up making it possible to port these passes to the new pass manager, and so it will end up factored away pretty reasonably. llvm-svn: 225131
* Add functions for finding ephemeral valuesHal Finkel2014-09-071-4/+10
| | | | | | | | | | | | | | | | This adds a set of utility functions for collecting 'ephemeral' values. These are LLVM IR values that are used only by @llvm.assume intrinsics (directly or indirectly), and thus will be removed prior to code generation, implying that they should be considered free for certain purposes (like inlining). The inliner's cost analysis, and a few other passes, have been updated to account for ephemeral values using the provided functionality. This functionality is important for the usability of @llvm.assume, because it limits the "non-local" side-effects of adding llvm.assume on inlining, loop unrolling, etc. (these are hints, and do not generate code, so they should not directly contribute to estimates of execution cost). llvm-svn: 217335
* Add an Assumption-Tracking PassHal Finkel2014-09-071-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | This adds an immutable pass, AssumptionTracker, which keeps a cache of @llvm.assume call instructions within a module. It uses callback value handles to keep stale functions and intrinsics out of the map, and it relies on any code that creates new @llvm.assume calls to notify it of the new instructions. The benefit is that code needing to find @llvm.assume intrinsics can do so directly, without scanning the function, thus allowing the cost of @llvm.assume handling to be negligible when none are present. The current design is intended to be lightweight. We don't keep track of anything until we need a list of assumptions in some function. The first time this happens, we scan the function. After that, we add/remove @llvm.assume calls from the cache in response to registration calls and ValueHandle callbacks. There are no new direct test cases for this pass, but because it calls it validation function upon module finalization, we'll pick up detectable inconsistencies from the other tests that touch @llvm.assume calls. This pass will be used by follow-up commits that make use of @llvm.assume. llvm-svn: 217334
* Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) ↵Duncan P. N. Exon Smith2014-07-211-3/+5
| | | | | | | | | iterator ranges." This reverts commit r213474 (and r213475), which causes a miscompile on a stage2 LTO build. I'll reply on the list in a moment. llvm-svn: 213562
* [C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ↵Manuel Jacob2014-07-201-5/+3
| | | | | | | | | | | | | | | | | | ranges. Summary: This patch introduces two new iterator ranges and updates existing code to use it. No functional change intended. Test Plan: All tests (make check-all) still pass. Reviewers: dblaikie Reviewed By: dblaikie Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D4481 llvm-svn: 213474
* [C++] Use 'nullptr'. Transforms edition.Craig Topper2014-04-251-19/+19
| | | | llvm-svn: 207196
* [Modules] Fix potential ODR violations by sinking the DEBUG_TYPEChandler Carruth2014-04-221-1/+2
| | | | | | | | | | | | | | | | | definition below all of the header #include lines, lib/Transforms/... edition. This one is tricky for two reasons. We again have a couple of passes that define something else before the includes as well. I've sunk their name macros with the DEBUG_TYPE. Also, InstCombine contains headers that need DEBUG_TYPE, so now those headers #define and #undef DEBUG_TYPE around their code, leaving them well formed modular headers. Fixing these headers was a large motivation for all of these changes, as "leaky" macros of this form are hard on the modules implementation. llvm-svn: 206844
* remove some dead codeNuno Lopes2014-04-171-21/+0
| | | | | | | | | | | | | | | lib/Analysis/IPA/InlineCost.cpp | 18 ------------------ lib/Analysis/RegionPass.cpp | 1 - lib/Analysis/TypeBasedAliasAnalysis.cpp | 1 - lib/Transforms/Scalar/LoopUnswitch.cpp | 21 --------------------- lib/Transforms/Utils/LCSSA.cpp | 2 -- lib/Transforms/Utils/LoopSimplify.cpp | 6 ------ utils/TableGen/AsmWriterEmitter.cpp | 13 ------------- utils/TableGen/DFAPacketizerEmitter.cpp | 7 ------- utils/TableGen/IntrinsicEmitter.cpp | 2 -- 9 files changed, 71 deletions(-) llvm-svn: 206506
* [C++11] Add range based accessors for the Use-Def chain of a Value.Chandler Carruth2014-03-091-14/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* [C++11] Add 'override' keyword to virtual methods that override their base ↵Craig Topper2014-03-051-3/+3
| | | | | | class. llvm-svn: 202953
* [C++11] Replace llvm::tie with std::tie.Benjamin Kramer2014-03-021-1/+1
| | | | | | The old implementation is no longer needed in C++11. llvm-svn: 202644
* Disable most IR-level transform passes on functions marked 'optnone'.Paul Robinson2014-02-061-0/+3
| | | | | | | | | Ideally only those transform passes that run at -O0 remain enabled, in reality we get as close as we reasonably can. Passes are responsible for disabling themselves, it's not the job of the pass manager to do it for them. llvm-svn: 200892
* [PM] Split DominatorTree into a concrete analysis result object whichChandler Carruth2014-01-131-3/+5
| | | | | | | | | | | | | | | | | | | | | | | can be used by both the new pass manager and the old. This removes it from any of the virtual mess of the pass interfaces and lets it derive cleanly from the DominatorTreeBase<> template. In turn, tons of boilerplate interface can be nuked and it turns into a very straightforward extension of the base DominatorTree interface. The old analysis pass is now a simple wrapper. The names and style of this split should match the split between CallGraph and CallGraphWrapperPass. All of the users of DominatorTree have been updated to match using many of the same tricks as with CallGraph. The goal is that the common type remains the resulting DominatorTree rather than the pass. This will make subsequent work toward the new pass manager significantly easier. Also in numerous places things became cleaner because I switched from re-running the pass (!!! mid way through some other passes run!!!) to directly recomputing the domtree. llvm-svn: 199104
* [cleanup] Move the Dominators.h and Verifier.h headers into the IRChandler Carruth2014-01-131-1/+1
| | | | | | | | | | | | | | | | | | directory. These passes are already defined in the IR library, and it doesn't make any sense to have the headers in Analysis. Long term, I think there is going to be a much better way to divide these matters. The dominators code should be fully separated into the abstract graph algorithm and have that put in Support where it becomes obvious that evn Clang's CFGBlock's can use it. Then the verifier can manually construct dominance information from the Support-driven interface while the Analysis library can provide a pass which both caches, reconstructs, and supports a nice update API. But those are very long term, and so I don't want to leave the really confusing structure until that day arrives. llvm-svn: 199082
* Remove dead code from LoopUnswitchHal Finkel2013-11-081-127/+0
| | | | | | | | | | | | LoopUnswitch's code simplification routine has logic to convert conditional branches into unconditional branches, after unswitching makes the condition constant, and then remove any blocks that renders dead. Unfortunately, this code is dead, currently broken, and furthermore, has never been alive (at least as far back at 2006). No functionality change intended. llvm-svn: 194277
* Adjust file to the coding standard.Jakub Staszak2013-08-061-53/+49
| | | | llvm-svn: 187808
* Use SmallVectorImpl& instead of SmallVector to avoid repeating small vector ↵Craig Topper2013-07-141-2/+2
| | | | | | size. llvm-svn: 186274
* Switch CodeMetrics itself over to use TTI to determine if an instructionChandler Carruth2013-01-211-4/+7
| | | | | | | | | | | | is free. The whole CodeMetrics API should probably be reworked more, but this is enough to allow deleting the duplicate code there for computing whether an instruction is free. All of the passes using this have been updated to pull in TTI and hand it to the CodeMetrics stuff. Further, a dead CodeMetrics API (analyzeFunction) is nuked for lack of users. llvm-svn: 173036
* Move all of the header files which are involved in modelling the LLVM IRChandler Carruth2013-01-021-4/+4
| | | | | | | | | | | | | | | | | | | | | into their new header subdirectory: include/llvm/IR. This matches the directory structure of lib, and begins to correct a long standing point of file layout clutter in LLVM. There are still more header files to move here, but I wanted to handle them in separate commits to make tracking what files make sense at each layer easier. The only really questionable files here are the target intrinsic tablegen files. But that's a battle I'd rather not fight today. I've updated both CMake and Makefile build systems (I think, and my tests think, but I may have missed something). I've also re-sorted the includes throughout the project. I'll be committing updates to Clang, DragonEgg, and Polly momentarily. llvm-svn: 171366
* Remove the Function::getFnAttributes method in favor of using the AttributeSetBill Wendling2012-12-301-1/+2
| | | | | | | | | directly. This is in preparation for removing the use of the 'Attribute' class as a collection of attributes. That will shift to the AttributeSet class instead. llvm-svn: 171253
* Add a new attribute, 'noduplicate'. If a function contains a noduplicate ↵James Molloy2012-12-201-0/+7
| | | | | | | | call, the call cannot be duplicated - Jump threading, loop unrolling, loop unswitching, and loop rotation are inhibited if they would duplicate the call. Similarly inlining of the function is inhibited, if that would duplicate the call (in particular inlining is still allowed when there is only one callsite and the function has internal linkage). llvm-svn: 170704
* Rename the 'Attributes' class to 'Attribute'. It's going to represent a ↵Bill Wendling2012-12-191-1/+1
| | | | | | single attribute in the future. llvm-svn: 170502
* Use the new script to sort the includes of every file under lib.Chandler Carruth2012-12-031-11/+11
| | | | | | | | | | | | | | | | | Sooooo many of these had incorrect or strange main module includes. I have manually inspected all of these, and fixed the main module include to be the nearest plausible thing I could find. If you own or care about any of these source files, I encourage you to take some time and check that these edits were sensible. I can't have broken anything (I strictly added headers, and reordered them, never removed), but they may not be the headers you'd really like to identify as containing the API being implemented. Many forward declarations and missing includes were added to a header files to allow them to parse cleanly when included first. The main module rule does in fact have its merits. =] llvm-svn: 169131
* Simplify code. No functionality change.Jakub Staszak2012-10-161-7/+3
| | | | llvm-svn: 166053
* Create enums for the different attributes.Bill Wendling2012-10-091-1/+2
| | | | | | | We use the enums to query whether an Attributes object has that attribute. The opaque layer is responsible for knowing where that specific attribute is stored. llvm-svn: 165488
* Remove the `hasFnAttr' method from Function.Bill Wendling2012-09-261-1/+1
| | | | | | | The hasFnAttr method has been replaced by querying the Attributes explicitly. No intended functionality change. llvm-svn: 164725
* Do not pass an invalid domtree to SimplifyInstruction fromPeter Collingbourne2012-05-201-2/+2
| | | | | | LoopUnswitch. Fixes PR12887. llvm-svn: 157140
* Second attempt at PR12573:Bill Wendling2012-04-301-2/+2
| | | | | | | | | | | Allow the "SplitCriticalEdge" function to split the edge to a landing pad. If the pass is *sure* that it thinks it knows what it's doing, then it may go ahead and specify that the landing pad can have its critical edge split. The loop unswitch pass is one of these passes. It will split the critical edges of all edges coming from a loop to a landing pad not within the loop. Doing so will retain important loop analysis information, such as loop simplify. llvm-svn: 155817
* Remove hack from r154987. The problem persists even with it, so it's not ↵Bill Wendling2012-04-301-11/+1
| | | | | | even a good hack. llvm-svn: 155813
* Put this expensive check below the less expensive ones.Bill Wendling2012-04-191-9/+9
| | | | llvm-svn: 155166
* Use a heavy hammer to fix PR12573.Bill Wendling2012-04-181-0/+9
| | | | | | | | | | | If the loop contains invoke instructions, whose unwind edge escapes the loop, then don't try to unswitch the loop. Doing so may cause the unwind edge to be split, which not only is non-trivial but doesn't preserve loop simplify information. Fixes PR12573 llvm-svn: 154987
* Fix 12513: Loop unrolling breaks with indirect branches.Andrew Trick2012-04-101-29/+12
| | | | | | | | Take this opportunity to generalize the indirectbr bailout logic for loop transformations. CFG transformations will never get indirectbr right, and there's no point trying. llvm-svn: 154386
* whitespaceAndrew Trick2012-04-101-140/+140
| | | | llvm-svn: 154385
* Fast fix for PR12343:Stepan Dyatkovskiy2012-04-021-4/+29
| | | | | | | | | | http://llvm.org/bugs/show_bug.cgi?id=12343 We have not trivial way for splitting edges that are goes from indirect branch. We can do it with some tricks, but it should be additionally discussed. And it is still dangerous due to difficulty of indirect branches controlling. Fix forbids this case for unswitching. llvm-svn: 153879
* This pass didn't want the inline cost per-se, it just wants generic codeChandler Carruth2012-03-151-1/+1
| | | | | | metrics. llvm-svn: 152760
* llvm::SwitchInstStepan Dyatkovskiy2012-03-111-3/+3
| | | | | | | Renamed methods caseBegin, caseEnd and caseDefault with case_begin, case_end, and case_default. Added some notes relative to case iterators. llvm-svn: 152532
* Taken into account Duncan's comments for r149481 dated by 2nd Feb 2012:Stepan Dyatkovskiy2012-03-081-9/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20120130/136146.html Implemented CaseIterator and it solves almost all described issues: we don't need to mix operand/case/successor indexing anymore. Base iterator class is implemented as a template since it may be initialized either from "const SwitchInst*" or from "SwitchInst*". ConstCaseIt is just a read-only iterator. CaseIt is read-write iterator; it allows to change case successor and case value. Usage of iterator allows totally remove resolveXXXX methods. All indexing convertions done automatically inside the iterator's getters. Main way of iterator usage looks like this: SwitchInst *SI = ... // intialize it somehow for (SwitchInst::CaseIt i = SI->caseBegin(), e = SI->caseEnd(); i != e; ++i) { BasicBlock *BB = i.getCaseSuccessor(); ConstantInt *V = i.getCaseValue(); // Do something. } If you want to convert case number to TerminatorInst successor index, just use getSuccessorIndex iterator's method. If you want initialize iterator from TerminatorInst successor index, use CaseIt::fromSuccessorIndex(...) method. There are also related changes in llvm-clients: klee and clang. llvm-svn: 152297
* SwitchInst refactoring.Stepan Dyatkovskiy2012-02-011-7/+8
| | | | | | | | | | | | | | | | | The purpose of refactoring is to hide operand roles from SwitchInst user (programmer). If you want to play with operands directly, probably you will need lower level methods than SwitchInst ones (TerminatorInst or may be User). After this patch we can reorganize SwitchInst operands and successors as we want. What was done: 1. Changed semantics of index inside the getCaseValue method: getCaseValue(0) means "get first case", not a condition. Use getCondition() if you want to resolve the condition. I propose don't mix SwitchInst case indexing with low level indexing (TI successors indexing, User's operands indexing), since it may be dangerous. 2. By the same reason findCaseValue(ConstantInt*) returns actual number of case value. 0 means first case, not default. If there is no case with given value, ErrorIndex will returned. 3. Added getCaseSuccessor method. I propose to avoid usage of TerminatorInst::getSuccessor if you want to resolve case successor BB. Use getCaseSuccessor instead, since internal SwitchInst organization of operands/successors is hidden and may be changed in any moment. 4. Added resolveSuccessorIndex and resolveCaseIndex. The main purpose of these methods is to see how case successors are really mapped in TerminatorInst. 4.1 "resolveSuccessorIndex" was created if you need to level down from SwitchInst to TerminatorInst. It returns TerminatorInst's successor index for given case successor. 4.2 "resolveCaseIndex" converts low level successors index to case index that curresponds to the given successor. Note: There are also related compatability fix patches for dragonegg, klee, llvm-gcc-4.0, llvm-gcc-4.2, safecode, clang. llvm-svn: 149481
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