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path: root/llvm/lib/Transforms/Scalar/CallSiteSplitting.cpp
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* [CallSiteSplitting] Do not crash when BB's terminator changes.Florian Hahn2018-03-061-1/+7
| | | | | | | | | | | | | | | Change doCallSiteSplitting to iterate until we reach the terminator instruction. tryToSplitCallSite can replace BB's terminator in case BB is a successor of itself. Then IE will be invalidated and we also have to check the current terminator. Reviewers: junbuml, davidxl, davide, fhahn Reviewed By: fhahn, junbuml Differential Revision: https://reviews.llvm.org/D43824 llvm-svn: 326793
* [CallSiteSplitting] fix use after-freeFedor Indutny2018-03-031-2/+7
| | | | | | | | Iterating through predecessors of `TailBB` while removing their terminators leads to use after-free, because the predecessor list is changing on each removal. llvm-svn: 326668
* [CallSiteSplitting] properly split musttail callsFedor Indutny2018-03-031-4/+72
| | | | | | | | | | | | | | | | | | | | Summary: `musttail` calls can't be naively splitted. The split blocks must include not only the call instruction itself, but also (optional) `bitcast` and `return` instructions that follow it. Clone `bitcast` and `ret`, place them into the split blocks, and remove the tail block when done. Reviewers: junbuml, mcrosier, davidxl, davide, fhahn Reviewed By: fhahn Subscribers: JDevlieghere, llvm-commits Differential Revision: https://reviews.llvm.org/D43729 llvm-svn: 326666
* Recommit r325001: [CallSiteSplitting] Support splitting of blocks with ↵Florian Hahn2018-02-141-22/+77
| | | | | | | | | | | | | | | | | | | | instrs before call. For basic blocks with instructions between the beginning of the block and a call we have to duplicate the instructions before the call in all split blocks and add PHI nodes for uses of the duplicated instructions after the call. Currently, the threshold for the number of instructions before a call is quite low, to keep the impact on binary size low. Reviewers: junbuml, mcrosier, davidxl, davide Reviewed By: junbuml Differential Revision: https://reviews.llvm.org/D41860 llvm-svn: 325126
* Revert r325001: [CallSiteSplitting] Support splitting of blocks with instrs ↵Florian Hahn2018-02-131-81/+22
| | | | | | | | before call. Due to memsan not being happy with the array of ValueToValue maps. llvm-svn: 325009
* [CallSiteSplitting] Clear ValueToValue maps.Florian Hahn2018-02-131-0/+4
| | | | llvm-svn: 325006
* [CallSiteSplitting] Dereference pointer earlier.Florian Hahn2018-02-131-3/+3
| | | | | | This should make the sanitizers happy. llvm-svn: 325004
* [CallSiteSplitting] Support splitting of blocks with instrs before call.Florian Hahn2018-02-131-22/+77
| | | | | | | | | | | | | | | | | | For basic blocks with instructions between the beginning of the block and a call we have to duplicate the instructions before the call in all split blocks and add PHI nodes for uses of the duplicated instructions after the call. Currently, the threshold for the number of instructions before a call is quite low, to keep the impact on binary size low. Reviewers: junbuml, mcrosier, davidxl, davide Reviewed By: junbuml Differential Revision: https://reviews.llvm.org/D41860 llvm-svn: 325001
* [CallSiteSplitting] Fix infinite loop when recording conditions.Florian Hahn2018-01-261-1/+2
| | | | | | | | | Fix infinite loop when recording conditions by correctly marking basic blocks as visited. Fixes https://bugs.llvm.org/show_bug.cgi?id=36105 llvm-svn: 323515
* [CallSiteSplitting] Pass list of (BB, Conditions) pairs to splitCallSite.Florian Hahn2018-01-161-76/+71
| | | | | | | | | | | | | | | This removes some duplication from splitCallSite and makes it easier to add additional code dealing with each predecessor. It also allows us to split for more than 2 predecessors, although that is not enabled for now. Reviewers: junbuml, mcrosier, davidxl, davide Reviewed By: junbuml Differential Revision: https://reviews.llvm.org/D41858 llvm-svn: 322599
* Use phi ranges to simplify code. No functionality change intended.Benjamin Kramer2017-12-301-7/+4
| | | | llvm-svn: 321585
* [CallSiteSplitting] Remove isOrHeader restriction.Florian Hahn2017-12-231-27/+19
| | | | | | | | | | | By following the single predecessors of the predecessors of the call site, we do not need to restrict the control flow. Reviewed By: junbuml, davide Differential Revision: https://reviews.llvm.org/D40729 llvm-svn: 321413
* [CallSiteSplitting] Refactor creating callsites.Florian Hahn2017-12-131-115/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This change makes the call site creation more general if any of the arguments is predicated on a condition in the call site's predecessors. If we find a callsite, that potentially can be split, we collect the set of conditions for the call site's predecessors (currently only 2 predecessors are allowed). To do that, we traverse each predecessor's predecessors as long as it only has single predecessors and record the condition, if it is relevant to the call site. For each condition, we also check if the condition is taken or not. In case it is not taken, we record the inverse predicate. We use the recorded conditions to create the new call sites and split the basic block. This has 2 benefits: (1) it is slightly easier to see what is going on (IMO) and (2) we can easily extend it to handle more complex control flow. Reviewers: davidxl, junbuml Reviewed By: junbuml Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D40728 llvm-svn: 320547
* [CallSiteSplitting] Don't let debug intrinsics affect optimizationsMikael Holmen2017-12-121-4/+5
| | | | | | | | | | | | | | | | | Summary: This solves PR35616. We don't want the compiler to generate different code when we compile with/without -g, so we now ignore debug intrinsics when determining if the optimization can trigger or not. Reviewers: junbuml Subscribers: davide, JDevlieghere, llvm-commits Differential Revision: https://reviews.llvm.org/D41068 llvm-svn: 320460
* [CallSiteSplitting] Remove some indirection (NFC).Florian Hahn2017-11-181-103/+85
| | | | | | | | | | | | | | | | Summary: With this patch I tried to reduce the complexity of the code sightly, by removing some indirection. Please let me know what you think. Reviewers: junbuml, mcrosier, davidxl Reviewed By: junbuml Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D40037 llvm-svn: 318593
* [CallSiteSplitting] clang-format my last commit. NFCI.Davide Italiano2017-11-041-3/+2
| | | | | | Thanks to Rui for pointing out. llvm-svn: 317393
* [CallSiteSplitting] Silence GCC's -Wparentheses. NFCI.Davide Italiano2017-11-031-2/+2
| | | | llvm-svn: 317385
* Recommit r317351 : Add CallSiteSplitting passJun Bum Lim2017-11-031-0/+493
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This recommit r317351 after fixing a buildbot failure. Original commit message: Summary: This change add a pass which tries to split a call-site to pass more constrained arguments if its argument is predicated in the control flow so that we can expose better context to the later passes (e.g, inliner, jump threading, or IPA-CP based function cloning, etc.). As of now we support two cases : 1) If a call site is dominated by an OR condition and if any of its arguments are predicated on this OR condition, try to split the condition with more constrained arguments. For example, in the code below, we try to split the call site since we can predicate the argument (ptr) based on the OR condition. Split from : if (!ptr || c) callee(ptr); to : if (!ptr) callee(null ptr) // set the known constant value else if (c) callee(nonnull ptr) // set non-null attribute in the argument 2) We can also split a call-site based on constant incoming values of a PHI For example, from : BB0: %c = icmp eq i32 %i1, %i2 br i1 %c, label %BB2, label %BB1 BB1: br label %BB2 BB2: %p = phi i32 [ 0, %BB0 ], [ 1, %BB1 ] call void @bar(i32 %p) to BB0: %c = icmp eq i32 %i1, %i2 br i1 %c, label %BB2-split0, label %BB1 BB1: br label %BB2-split1 BB2-split0: call void @bar(i32 0) br label %BB2 BB2-split1: call void @bar(i32 1) br label %BB2 BB2: %p = phi i32 [ 0, %BB2-split0 ], [ 1, %BB2-split1 ] llvm-svn: 317362
* Revert "Add CallSiteSplitting pass"Jun Bum Lim2017-11-031-492/+0
| | | | | | | | Revert due to Buildbot failure. This reverts commit r317351. llvm-svn: 317353
* Add CallSiteSplitting passJun Bum Lim2017-11-031-0/+492
Summary: This change add a pass which tries to split a call-site to pass more constrained arguments if its argument is predicated in the control flow so that we can expose better context to the later passes (e.g, inliner, jump threading, or IPA-CP based function cloning, etc.). As of now we support two cases : 1) If a call site is dominated by an OR condition and if any of its arguments are predicated on this OR condition, try to split the condition with more constrained arguments. For example, in the code below, we try to split the call site since we can predicate the argument (ptr) based on the OR condition. Split from : if (!ptr || c) callee(ptr); to : if (!ptr) callee(null ptr) // set the known constant value else if (c) callee(nonnull ptr) // set non-null attribute in the argument 2) We can also split a call-site based on constant incoming values of a PHI For example, from : BB0: %c = icmp eq i32 %i1, %i2 br i1 %c, label %BB2, label %BB1 BB1: br label %BB2 BB2: %p = phi i32 [ 0, %BB0 ], [ 1, %BB1 ] call void @bar(i32 %p) to BB0: %c = icmp eq i32 %i1, %i2 br i1 %c, label %BB2-split0, label %BB1 BB1: br label %BB2-split1 BB2-split0: call void @bar(i32 0) br label %BB2 BB2-split1: call void @bar(i32 1) br label %BB2 BB2: %p = phi i32 [ 0, %BB2-split0 ], [ 1, %BB2-split1 ] Reviewers: davidxl, huntergr, chandlerc, mcrosier, eraman, davide Reviewed By: davidxl Subscribers: sdesmalen, ashutosh.nema, fhahn, mssimpso, aemerson, mgorny, mehdi_amini, kristof.beyls, llvm-commits Differential Revision: https://reviews.llvm.org/D39137 llvm-svn: 317351
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