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* [IPSCCP,PM] Preserve PDT in the new pass manager.Florian Hahn2018-11-111-4/+3
| | | | | | | | | | Reviewers: kuhar, chandlerc, NutshellySima, brzycki Reviewed By: NutshellySima, brzycki Differential Revision: https://reviews.llvm.org/D54317 llvm-svn: 346618
* [IPSCCP,PM] Preserve DT in the new pass manager.Florian Hahn2018-11-091-27/+38
| | | | | | | | | | | | | | After D45330, Dominators are required for IPSCCP and can be preserved. This patch preserves DominatorTreeAnalysis in the new pass manager. AFAIK the legacy pass manager cannot preserve function analysis required by a module analysis. Reviewers: davide, dberlin, chandlerc, efriedma, kuhar, NutshellySima Reviewed By: chandlerc, kuhar, NutshellySima Differential Revision: https://reviews.llvm.org/D47259 llvm-svn: 346486
* Add support for llvm.is.constant intrinsic (PR4898)James Y Knight2018-11-071-0/+2
| | | | | | | | | | | | | | | This adds the llvm-side support for post-inlining evaluation of the __builtin_constant_p GCC intrinsic. Also fixed SCCPSolver::visitCallSite to not blow up when seeing a call to a function where canConstantFoldTo returns true, and one of the arguments is a struct. Updated from patch initially by Janusz Sobczak. Differential Revision: https://reviews.llvm.org/D4276 llvm-svn: 346322
* [TI removal] Rework `InstVisitor` to support visiting instructions thatChandler Carruth2018-10-151-8/+8
| | | | | | | | | are terminators without relying on the specific `TerminatorInst` type. This required cleaning up two users of `InstVisitor`s usage of `TerminatorInst` as well. llvm-svn: 344503
* [TI removal] Make variables declared as `TerminatorInst` and initializedChandler Carruth2018-10-151-1/+1
| | | | | | | | | | | | | by `getTerminator()` calls instead be declared as `Instruction`. This is the biggest remaining chunk of the usage of `getTerminator()` that insists on the narrow type and so is an easy batch of updates. Several files saw more extensive updates where this would cascade to requiring API updates within the file to use `Instruction` instead of `TerminatorInst`. All of these were trivial in nature (pervasively using `Instruction` instead just worked). llvm-svn: 344502
* SCCP: avoid caching DenseMap entry that might be invalidated.Tim Northover2018-10-121-3/+5
| | | | | | | Later calls to getValueState might insert entries into the ValueState map and cause reallocation, invalidating a reference. llvm-svn: 344327
* [IPSCCP] Fix a problem with removing labels in a switch with undef conditionBjorn Pettersson2018-09-201-25/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Before removing basic blocks that ipsccp has considered as dead all uses of the basic block label must be removed. That is done by calling ConstantFoldTerminator on the users. An exception is when the branch condition is an undef value. In such scenarios ipsccp is using some internal assumptions regarding which edge in the control flow that should remain, while ConstantFoldTerminator don't know how to fold the terminator. The problem addressed here is related to ConstantFoldTerminator's ability to rewrite a 'switch' into a conditional 'br'. In such situations ConstantFoldTerminator returns true indicating that the terminator has been rewritten. However, ipsccp treated the true value as if the edge to the dead basic block had been removed. So the code for resolving an undef branch condition did not trigger, and we ended up with assertion that there were uses remaining when deleting the basic block. The solution is to resolve indeterminate branches before the call to ConstantFoldTerminator. Reviewers: efriedma, fhahn, davide Reviewed By: fhahn Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D52232 llvm-svn: 342632
* [IR] Replace `isa<TerminatorInst>` with `isTerminator()`.Chandler Carruth2018-08-261-1/+1
| | | | | | | | | | | | This is a bit awkward in a handful of places where we didn't even have an instruction and now we have to see if we can build one. But on the whole, this seems like a win and at worst a reasonable cost for removing `TerminatorInst`. All of this is part of the removal of `TerminatorInst` from the `Instruction` type hierarchy. llvm-svn: 340701
* [IR] Sink `isExceptional` predicate to `Instruction`, rename it toChandler Carruth2018-08-261-1/+1
| | | | | | | | | | | `isExceptionalTermiantor` and implement it for opcodes as well following the common pattern in `Instruction`. Part of removing `TerminatorInst` from the `Instruction` type hierarchy to make it easier to share logic and interfaces between instructions that are both terminators and not terminators. llvm-svn: 340699
* [SCCP] Remove unused variable added in r340525.Florian Hahn2018-08-231-1/+1
| | | | llvm-svn: 340526
* Recommit r333268: [IPSCCP] Use PredicateInfo to propagate facts from cmp ↵Florian Hahn2018-08-231-8/+115
| | | | | | | | | | | | | | | | | | | | | | instructions. This version of the patch fixes cleaning up ssa_copy intrinsics, so it does not crash for instructions in blocks that have been marked unreachable. This patch updates IPSCCP to use PredicateInfo to propagate facts to true branches predicated by EQ and to false branches predicated by NE. As a follow up, we should be able to extend it to also propagate additional facts about nonnull. Reviewers: davide, mssimpso, dberlin, efriedma Reviewed By: davide, dberlin Differential Revision: https://reviews.llvm.org/D45330 llvm-svn: 340525
* Revert r337904: [IPSCCP] Use PredicateInfo to propagate facts from cmp ↵Florian Hahn2018-07-251-118/+8
| | | | | | | | instructions. I suspect it is causing the clang-stage2-Rthinlto failures. llvm-svn: 337956
* Recommit r333268: [IPSCCP] Use PredicateInfo to propagate facts from cmp ↵Florian Hahn2018-07-251-8/+118
| | | | | | | | | | | | | | | | | | | | instructions. r337828 resolves a PredicateInfo issue with unnamed types. Original message: This patch updates IPSCCP to use PredicateInfo to propagate facts to true branches predicated by EQ and to false branches predicated by NE. As a follow up, we should be able to extend it to also propagate additional facts about nonnull. Reviewers: davide, mssimpso, dberlin, efriedma Reviewed By: davide, dberlin llvm-svn: 337904
* [IPSCCP] Fix for bot failure caused by r337548Florian Hahn2018-07-201-1/+1
| | | | llvm-svn: 337554
* Recommit r328307: [IPSCCP] Use constant range information for comparisons of ↵Florian Hahn2018-07-201-110/+80
| | | | | | | | | | | | | | | | | | | | | | | | | | | parameters. This version contains a fix to add values for which the state in ParamState change to the worklist if the state in ValueState did not change. To avoid adding the same value multiple times, mergeInValue returns true, if it added the value to the worklist. The value is added to the worklist depending on its state in ValueState. Original message: For comparisons with parameters, we can use the ParamState lattice elements which also provide constant range information. This improves the code for PR33253 further and gets us closer to use ValueLatticeElement for all values. Also, as we are using the range information in the solver directly, we do not need tryToReplaceWithConstantRange afterwards anymore. Reviewers: dberlin, mssimpso, davide, efriedma Reviewed By: mssimpso Differential Revision: https://reviews.llvm.org/D43762 llvm-svn: 337548
* [SCCP] Don't use markForcedConstant on branch conditions.Eli Friedman2018-07-191-73/+62
| | | | | | | | | | | | It's more aggressive than we need to be, and leads to strange workarounds in other places like call return value inference. Instead, just directly mark an edge viable. Tests by Florian Hahn. Differential Revision: https://reviews.llvm.org/D49408 llvm-svn: 337507
* [IPSCCP] Run Solve each time we resolved an undef in a function.Florian Hahn2018-07-171-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Once we resolved an undef in a function we can run Solve, which could lead to finding a constant return value for the function, which in turn could turn undefs into constants in other functions that call it, before resolving undefs there. Computationally the amount of work we are doing stays the same, just the order we process things is slightly different and potentially there are a few less undefs to resolve. We are still relying on the order of functions in the IR, which means depending on the order, we are able to resolve the optimal undef first or not. For example, if @test1 comes before @testf, we find the constant return value of @testf too late and we cannot use it while solving @test1. This on its own does not lead to more constants removed in the test-suite, probably because currently we have to be very lucky to visit applicable functions in the right order. Maybe we manage to come up with a better way of resolving undefs in more 'profitable' functions first. Reviewers: efriedma, mssimpso, davide Reviewed By: efriedma, davide Differential Revision: https://reviews.llvm.org/D49385 llvm-svn: 337283
* Temporarily revert "Recommit r328307: [IPSCCP] Use constant range ↵Eric Christopher2018-07-121-81/+111
| | | | | | | | | | information for comparisons of parameters." as it's causing miscompiles. A testcase was provided in the original review thread. This reverts commit r336098. llvm-svn: 336877
* llvm: Add support for "-fno-delete-null-pointer-checks"Manoj Gupta2018-07-091-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Support for this option is needed for building Linux kernel. This is a very frequently requested feature by kernel developers. More details : https://lkml.org/lkml/2018/4/4/601 GCC option description for -fdelete-null-pointer-checks: This Assume that programs cannot safely dereference null pointers, and that no code or data element resides at address zero. -fno-delete-null-pointer-checks is the inverse of this implying that null pointer dereferencing is not undefined. This feature is implemented in LLVM IR in this CL as the function attribute "null-pointer-is-valid"="true" in IR (Under review at D47894). The CL updates several passes that assumed null pointer dereferencing is undefined to not optimize when the "null-pointer-is-valid"="true" attribute is present. Reviewers: t.p.northover, efriedma, jyknight, chandlerc, rnk, srhines, void, george.burgess.iv Reviewed By: efriedma, george.burgess.iv Subscribers: eraman, haicheng, george.burgess.iv, drinkcat, theraven, reames, sanjoy, xbolva00, llvm-commits Differential Revision: https://reviews.llvm.org/D47895 llvm-svn: 336613
* Recommit r328307: [IPSCCP] Use constant range information for comparisons of ↵Florian Hahn2018-07-021-111/+81
| | | | | | | | | | | | | | | | | | | | | | | | | | | parameters. This version contains a fix to add values for which the state in ParamState change to the worklist if the state in ValueState did not change. To avoid adding the same value multiple times, mergeInValue returns true, if it added the value to the worklist. The value is added to the worklist depending on its state in ValueState. Original message: For comparisons with parameters, we can use the ParamState lattice elements which also provide constant range information. This improves the code for PR33253 further and gets us closer to use ValueLatticeElement for all values. Also, as we are using the range information in the solver directly, we do not need tryToReplaceWithConstantRange afterwards anymore. Reviewers: dberlin, mssimpso, davide, efriedma Reviewed By: mssimpso Differential Revision: https://reviews.llvm.org/D43762 llvm-svn: 336098
* [SCCP] Mark CFG as preserved.Florian Hahn2018-06-281-0/+2
| | | | | | | | | | | | SCCP does not change the CFG, so we can mark it as preserved. Reviewers: dberlin, efriedma, davide Reviewed By: davide Differential Revision: https://reviews.llvm.org/D47149 llvm-svn: 335820
* [IPSCCP] Change dead blocks to unreachable after visiting all executable blocks.Florian Hahn2018-06-261-3/+11
| | | | | | | | | | | | | | | | | changeToUnreachable may remove PHI nodes from executable blocks we found values for and we would fail to replace them. By changing dead blocks to unreachable after we replaced constants in all executable blocks, we ensure such PHI nodes are replaced by their known value before. Fixes PR37780. Reviewers: efriedma, davide Reviewed By: efriedma Differential Revision: https://reviews.llvm.org/D48421 llvm-svn: 335588
* Revert r335206 "Recommit r333268: [IPSCCP] Use PredicateInfo to propagate ↵Francis Visoiu Mistrih2018-06-211-112/+8
| | | | | | | | | | | facts from cmp instructions." This reverts commit r335206. As discussed here: https://reviews.llvm.org/rL333740, a fix will come tomorrow. In the meanwhile, revert this to fix some bots. llvm-svn: 335272
* Recommit r333268: [IPSCCP] Use PredicateInfo to propagate facts from cmp ↵Florian Hahn2018-06-211-8/+112
| | | | | | | | | | | | | | | | | | | | | instructions. r335150 should resolve the issues with the clang-with-thin-lto-ubuntu and clang-with-lto-ubuntu builders. Original message: This patch updates IPSCCP to use PredicateInfo to propagate facts to true branches predicated by EQ and to false branches predicated by NE. As a follow up, we should be able to extend it to also propagate additional facts about nonnull. Reviewers: davide, mssimpso, dberlin, efriedma Reviewed By: davide, dberlin llvm-svn: 335206
* Move Analysis/Utils/Local.h back to TransformsDavid Blaikie2018-06-041-1/+1
| | | | | | | | | | Review feedback from r328165. Split out just the one function from the file that's used by Analysis. (As chandlerc pointed out, the original change only moved the header and not the implementation anyway - which was fine for the one function that was used (since it's a template/inlined in the header) but not in general) llvm-svn: 333954
* Revert r333740: IPSCCP] Use PredicateInfo to propagate facts from cmp.Florian Hahn2018-06-011-112/+8
| | | | | | This is breaking the clang-with-thin-lto-ubuntu bot. llvm-svn: 333745
* Recommit r333268: [IPSCCP] Use PredicateInfo to propagate facts from cmp ↵Florian Hahn2018-06-011-8/+112
| | | | | | | | | | | | | | | | | | | instructions. This patch updates IPSCCP to use PredicateInfo to propagate facts to true branches predicated by EQ and to false branches predicated by NE. As a follow up, we should be able to extend it to also propagate additional facts about nonnull. Reviewers: davide, mssimpso, dberlin, efriedma Reviewed By: davide, dberlin Differential Revision: https://reviews.llvm.org/D45330 llvm-svn: 333740
* Revert r333268: [IPSCCP] Use PredicateInfo to propagate facts from...Florian Hahn2018-05-251-112/+8
| | | | | | | | | | | | | | | | | | | | | | Reverting this to see if this is causing the failures of the clang-with-thin-lto-ubuntu bot. [IPSCCP] Use PredicateInfo to propagate facts from cmp instructions. This patch updates IPSCCP to use PredicateInfo to propagate facts to true branches predicated by EQ and to false branches predicated by NE. As a follow up, we should be able to extend it to also propagate additional facts about nonnull. Reviewers: davide, mssimpso, dberlin, efriedma Reviewed By: davide, dberlin Differential Revision: https://reviews.llvm.org/D45330 llvm-svn: 333323
* [IPSCCP] Use PredicateInfo to propagate facts from cmp instructions.Florian Hahn2018-05-251-8/+112
| | | | | | | | | | | | | | | | | This patch updates IPSCCP to use PredicateInfo to propagate facts to true branches predicated by EQ and to false branches predicated by NE. As a follow up, we should be able to extend it to also propagate additional facts about nonnull. Reviewers: davide, mssimpso, dberlin, efriedma Reviewed By: davide, dberlin Differential Revision: https://reviews.llvm.org/D45330 llvm-svn: 333268
* Rename DEBUG macro to LLVM_DEBUG.Nicola Zaghen2018-05-141-32/+32
| | | | | | | | | | | | | | | | The DEBUG() macro is very generic so it might clash with other projects. The renaming was done as follows: - git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g' - git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM - Manual change to APInt - Manually chage DOCS as regex doesn't match it. In the transition period the DEBUG() macro is still present and aliased to the LLVM_DEBUG() one. Differential Revision: https://reviews.llvm.org/D43624 llvm-svn: 332240
* Revert r328307: [IPSCCP] Use constant range information for comparisons of ↵Florian Hahn2018-03-231-17/+50
| | | | | | | | parameters. Reverted for now, due to it causing verifier failures. llvm-svn: 328312
* [IPSCCP] Use constant range information for comparisons of parameters.Florian Hahn2018-03-231-50/+17
| | | | | | | | | | | | | | | | | | For comparisons with parameters, we can use the ParamState lattice elements which also provide constant range information. This improves the code for PR33253 further and gets us closer to use ValueLatticeElement for all values. Also, as we are using the range information in the solver directly, we do not need tryToReplaceWithConstantRange afterwards anymore. Reviewers: dberlin, mssimpso, davide, efriedma Reviewed By: mssimpso Differential Revision: https://reviews.llvm.org/D43762 llvm-svn: 328307
* Fix layering between SCCP and IPO SCCPDavid Blaikie2018-03-221-57/+3
| | | | | | | | | | Transforms/Scalar/SCCP.cpp implemented both the Scalar and IPO SCCP, but this meant Transforms/Scalar including Transfroms/IPO headers, creating a circular dependency. (IPO depends on Scalar already) - so move the IPO SCCP shims out into IPO and the basic library implementation accessible from Scalar/SCCP.h to be used from the IPO/SCCP.cpp implementation. llvm-svn: 328250
* Fix a couple of layering violations in TransformsDavid Blaikie2018-03-211-2/+2
| | | | | | | | | | | | | Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering. Transforms depends on Transforms/Utils, not the other way around. So remove the header and the "createStripGCRelocatesPass" function declaration (& definition) that is unused and motivated this dependency. Move Transforms/Utils/Local.h into Analysis because it's used by Analysis/MemoryBuiltins.cpp. llvm-svn: 328165
* [IPSCCP] Add getCompare which returns either true, false, undef or null.Florian Hahn2018-03-051-6/+1
| | | | | | | | | | | | | | | getCompare returns true, false or undef constants if the comparison can be evaluated, or nullptr if it cannot. This is in line with what ConstantExpr::getCompare returns. It also allows us to use ConstantExpr::getCompare for comparing constants. Reviewers: davide, mssimpso, dberlin, anna Reviewed By: davide Differential Revision: https://reviews.llvm.org/D43761 llvm-svn: 326720
* [SCCP] Fix unused variable warning in release builds.Benjamin Kramer2018-03-011-0/+1
| | | | llvm-svn: 326429
* [IPSCCP] do not break musttail invariant (PR36485)Reid Kleckner2018-03-011-1/+55
| | | | | | | | | | | | | | | | | Do not replace results of `musttail` calls with a constant if the call itself can't be removed. Do not zap returns of `musttail` callees, if the call site can't be removed and replaced with a constant. Do not zap returns of `musttail`-calling blocks, this breaks invariant too. Patch by Fedor Indutny Differential Revision: https://reviews.llvm.org/D43695 llvm-svn: 326404
* [IPSCCP] Remove calls without side effectsChris Bieneman2018-01-091-1/+1
| | | | | | | | | | | | | | | Summary: When performing constant propagation for call instructions we have historically replaced all uses of the return from a call, but not removed the call itself. This is required for correctness if the calls have side effects, however the compiler should be able to safely remove calls that don't have side effects. This allows the compiler to completely fold away calls to functions that have no side effects if the inputs are constant and the output can be determined at compile time. Reviewers: davide, sanjoy, bruno, dberlin Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D38856 llvm-svn: 322125
* Revert "[SCCP] Manually fold branches on undef."Davide Italiano2018-01-071-26/+3
| | | | | | | I thought this was responsible for PR35723, but I was wrong, the issue lies elsewhere. Revert while I debug. llvm-svn: 321975
* Use phi ranges to simplify code. No functionality change intended.Benjamin Kramer2017-12-301-4/+2
| | | | llvm-svn: 321585
* [SCCP] Manually fold branches on undef.Davide Italiano2017-12-231-3/+26
| | | | | | | | | | | | | | | This code was originally removed and replace with an assertion because believed unnecessary. It turns out there was simply no test coverage for this case, and the constant folder doesn't yet know about patterns like `br undef %label1, %label2`. Presumably at some point the constant folder might learn about these patterns, but it's a broader change. A testcase will be added to make sure this doesn't regress again in the future. Fixes PR35723. llvm-svn: 321402
* [SCCP] Pick the right lattice value for constants.Davide Italiano2017-11-221-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | After the dataflow algorithm proves that an argument is constant, it replaces it value with the integer constant and drops the lattice value associated to the DEF. e.g. in the example we have @f() that's called twice: call @f(undef, ...) call @f(2, ...) `undef` MEET 2 = 2 so we replace the argument and all its uses with the constant 2. Shortly after, tryToReplaceWithConstantRange() tries to get the lattice value for the argument we just replaced, causing an assertion. This function is a little peculiar as it runs when we're doing replacement and not as part of the solver but still queries the solver. The fix is that of checking whether we replaced the value already and get a temporary lattice value for the constant. Thanks to Zhendong Su for the report! Fixes PR35357. llvm-svn: 318817
* [SCCP] If we replace with a constant, we can't replace with a range.Davide Italiano2017-11-211-1/+3
| | | | | | This microoptimization is NFC. llvm-svn: 318711
* Recommit r315288: [SCCP] Propagate integer range info for parameters in IPSCCP.Florian Hahn2017-10-301-7/+95
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This version of the patch includes a fix addressing a stage2 LTO buildbot failure and addressed some additional nits. Original commit message: This updates the SCCP solver to use of the ValueElement lattice for parameters, which provides integer range information. The range information is used to remove unneeded icmp instructions. For the following function, f() can be optimized to ret i32 2 with this change source_filename = "sccp.c" target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" ; Function Attrs: norecurse nounwind readnone uwtable define i32 @main() local_unnamed_addr #0 { entry: %call = tail call fastcc i32 @f(i32 1) %call1 = tail call fastcc i32 @f(i32 47) %add3 = add nsw i32 %call, %call1 ret i32 %add3 } ; Function Attrs: noinline norecurse nounwind readnone uwtable define internal fastcc i32 @f(i32 %x) unnamed_addr #1 { entry: %c1 = icmp sle i32 %x, 100 %cmp = icmp sgt i32 %x, 300 %. = select i1 %cmp, i32 1, i32 2 ret i32 %. } attributes #1 = { noinline } Reviewers: davide, sanjoy, efriedma, dberlin Reviewed By: davide, dberlin Subscribers: mcrosier, gberry, mssimpso, dberlin, llvm-commits Differential Revision: https://reviews.llvm.org/D36656 llvm-svn: 316891
* Revert r316887 to fix buildbot failures.Florian Hahn2017-10-301-93/+7
| | | | llvm-svn: 316888
* Recommit r315288: [SCCP] Propagate integer range info for parameters in IPSCCP.Florian Hahn2017-10-301-7/+93
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This version of the patch includes a fix addressing a stage2 LTO buildbot failure and addressed some additional nits. Original commit message: This updates the SCCP solver to use of the ValueElement lattice for parameters, which provides integer range information. The range information is used to remove unneeded icmp instructions. For the following function, f() can be optimized to ret i32 2 with this change source_filename = "sccp.c" target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" ; Function Attrs: norecurse nounwind readnone uwtable define i32 @main() local_unnamed_addr #0 { entry: %call = tail call fastcc i32 @f(i32 1) %call1 = tail call fastcc i32 @f(i32 47) %add3 = add nsw i32 %call, %call1 ret i32 %add3 } ; Function Attrs: noinline norecurse nounwind readnone uwtable define internal fastcc i32 @f(i32 %x) unnamed_addr #1 { entry: %c1 = icmp sle i32 %x, 100 %cmp = icmp sgt i32 %x, 300 %. = select i1 %cmp, i32 1, i32 2 ret i32 %. } attributes #1 = { noinline } Reviewers: davide, sanjoy, efriedma, dberlin Reviewed By: davide, dberlin Subscribers: mcrosier, gberry, mssimpso, dberlin, llvm-commits Differential Revision: https://reviews.llvm.org/D36656 llvm-svn: 316887
* [Transforms] Fix some Clang-tidy modernize and Include What You Use ↵Eugene Zelenko2017-10-201-58/+59
| | | | | | warnings; other minor fixes (NFC). llvm-svn: 316241
* [IPSCCP] Move common functions to ValueLatticeUtils (NFC)Matthew Simpson2017-10-131-62/+27
| | | | | | | | | | | This patch moves some common utility functions out of IPSCCP and makes them available globally. The functions determine if interprocedural data-flow analyses can propagate information through function returns, arguments, and global variables. Differential Revision: https://reviews.llvm.org/D37638 llvm-svn: 315719
* Revert "Reintroduce "[SCCP] Propagate integer range info for parameters in ↵Bruno Cardoso Lopes2017-10-121-92/+8
| | | | | | | | | | | IPSCCP."" This reverts commit r315593: still affect two bots: http://lab.llvm.org:8011/builders/clang-with-lto-ubuntu/builds/5308 http://green.lab.llvm.org/green/job/clang-stage2-configure-Rlto/21751/ llvm-svn: 315618
* Reintroduce "[SCCP] Propagate integer range info for parameters in IPSCCP."Bruno Cardoso Lopes2017-10-121-8/+92
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is r315288 & r315294, which were reverted due to stage2 bot failures. Summary: This updates the SCCP solver to use of the ValueElement lattice for parameters, which provides integer range information. The range information is used to remove unneeded icmp instructions. For the following function, f() can be optimized to `ret i32 2` with this change source_filename = "sccp.c" target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" ; Function Attrs: norecurse nounwind readnone uwtable define i32 @main() local_unnamed_addr #0 { entry: %call = tail call fastcc i32 @f(i32 1) %call1 = tail call fastcc i32 @f(i32 47) %add3 = add nsw i32 %call, %call1 ret i32 %add3 } ; Function Attrs: noinline norecurse nounwind readnone uwtable define internal fastcc i32 @f(i32 %x) unnamed_addr #1 { entry: %c1 = icmp sle i32 %x, 100 %cmp = icmp sgt i32 %x, 300 %. = select i1 %cmp, i32 1, i32 2 ret i32 %. } attributes #1 = { noinline } Reviewers: davide, sanjoy, efriedma, dberlin Reviewed By: davide, dberlin Subscribers: mcrosier, gberry, mssimpso, dberlin, llvm-commits Differential Revision: https://reviews.llvm.org/D36656 llvm-svn: 315593
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