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* [Statistics] Add a method to atomically update a statistic that contains a ↵Craig Topper2017-05-181-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | maximum Summary: There are several places in the codebase that try to calculate a maximum value in a Statistic object. We currently do this in one of two ways: MaxNumFoo = std::max(MaxNumFoo, NumFoo); or MaxNumFoo = (MaxNumFoo > NumFoo) ? MaxNumFoo : NumFoo; The first version reads from MaxNumFoo one time and uncontionally rwrites to it. The second version possibly reads it twice depending on the result of the first compare. But we have no way of knowing if the value was changed by another thread between the reads and the writes. This patch adds a method to the Statistic object that can ensure that we only store if our value is the max and the previous max didn't change after we read it. If it changed we'll recheck if our value should still be the max or not and try again. This spawned from an audit I'm trying to do of all places we uses the implicit conversion to unsigned on the Statistics objects. See my previous thread on llvm-dev https://groups.google.com/forum/#!topic/llvm-dev/yfvxiorKrDQ Reviewers: dberlin, chandlerc, hfinkel, dblaikie Reviewed By: chandlerc Subscribers: llvm-commits, sanjoy Differential Revision: https://reviews.llvm.org/D33301 llvm-svn: 303318
* Elide stores which are overwritten without being observed.Nirav Dave2017-05-161-7/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: In SelectionDAG, when a store is immediately chained to another store to the same address, elide the first store as it has no observable effects. This is causes small improvements dealing with intrinsics lowered to stores. Test notes: * Many testcases overwrite store addresses multiple times and needed minor changes, mainly making stores volatile to prevent the optimization from optimizing the test away. * Many X86 test cases optimized out instructions associated with associated with va_start. * Note that test_splat in CodeGen/AArch64/misched-stp.ll no longer has dependencies to check and can probably be removed and potentially replaced with another test. Reviewers: rnk, john.brawn Subscribers: aemerson, rengolin, qcolombet, jyknight, nemanjai, nhaehnle, javed.absar, llvm-commits Differential Revision: https://reviews.llvm.org/D33206 llvm-svn: 303198
* [DAG] Prune deleted nodes in TokenFactorNirav Dave2017-05-161-8/+3
| | | | | | Fix visitTokenFactor to correctly remove deleted nodes. NFC. llvm-svn: 303181
* IR: Give function GlobalValue::getRealLinkageName() a less misleading name: ↵Peter Collingbourne2017-05-161-2/+2
| | | | | | | | | | | | dropLLVMManglingEscape(). This function gives the wrong answer on some non-ELF platforms in some cases. The function that does the right thing lives in Mangler.h. To try to discourage people from using this function, give it a different name. Differential Revision: https://reviews.llvm.org/D33162 llvm-svn: 303134
* [SelectionDAG] Added support for EXTRACT_SUBVECTOR/CONCAT_VECTORS ↵Simon Pilgrim2017-05-131-7/+29
| | | | | | demandedelts in ComputeNumSignBits llvm-svn: 302997
* [SelectionDAG] Add VECTOR_SHUFFLE support to ComputeNumSignBitsSimon Pilgrim2017-05-131-0/+34
| | | | llvm-svn: 302993
* [ValueTracking] Remove const_casts on several calls to computeKnownBits and ↵Craig Topper2017-05-131-2/+1
| | | | | | ComputeSignBit. NFC llvm-svn: 302991
* [PPC] Move the combine "a << (b % (sizeof(a) * 8)) -> (PPCshl a, b)" to the ↵Tim Shen2017-05-121-33/+0
| | | | | | | | | | | | | | | | | | | | | | backend. NFC. Summary: Eli pointed out that it's unsafe to combine the shifts to ISD::SHL etc., because those are not defined for b > sizeof(a) * 8, even after some of the combiners run. However, PPCISD::SHL defines that behavior (as the instructions themselves). Move the combination to the backend. The tests in shift_mask.ll still pass. Reviewers: echristo, hfinkel, efriedma, iteratee Subscribers: nemanjai, llvm-commits Differential Revision: https://reviews.llvm.org/D33076 llvm-svn: 302937
* [KnownBits] Add bit counting methods to KnownBits struct and use them where ↵Craig Topper2017-05-122-31/+26
| | | | | | | | | | | | possible This patch adds min/max population count, leading/trailing zero/one bit counting methods. The min methods return answers based on bits that are known without considering unknown bits. The max methods give answers taking into account the largest count that unknown bits could give. Differential Revision: https://reviews.llvm.org/D32931 llvm-svn: 302925
* [DAGCombine] Use SelectionDAG::getAnyExtOrTrunc helper. NFCI.Simon Pilgrim2017-05-121-8/+2
| | | | llvm-svn: 302907
* [DAGCombine] Use SelectionDAG::getZExtOrTrunc helper. NFCI.Simon Pilgrim2017-05-121-8/+2
| | | | llvm-svn: 302897
* Use SDValue::getOperand() helper. NFCI.Simon Pilgrim2017-05-122-22/+19
| | | | llvm-svn: 302896
* [MSP430] Generate EABI-compliant libcallsVadzim Dambrouski2017-05-111-0/+1
| | | | | | | | | | | | | Updates the MSP430 target to generate EABI-compatible libcall names. As a byproduct, adjusts the hardware multiplier options available in the MSP430 target, adds support for promotion of the ISD::MUL operation for 8-bit integers, and correctly marks R11 as used by call instructions. Patch by Andrew Wygle. Differential Revision: https://reviews.llvm.org/D32676 llvm-svn: 302820
* [DAGCombine] Use SelectionDAG::getAnyExtOrTrunc helper. NFCI.Simon Pilgrim2017-05-111-18/+4
| | | | llvm-svn: 302808
* Strip trailing whitespace. NFCI.Simon Pilgrim2017-05-111-1/+1
| | | | llvm-svn: 302784
* Revert "[SDAG] Relax conditions under stores of loaded values can be merged"David L. Jones2017-05-101-22/+10
| | | | | | | | | | | | | | | | | | | | | This reverts r302712. The change fails with ASAN enabled: ERROR: AddressSanitizer: use-after-poison on address ... at ... READ of size 2 at ... thread T0 #0 ... in llvm::SDNode::getNumValues() const <snip>/include/llvm/CodeGen/SelectionDAGNodes.h:855:42 #1 ... in llvm::SDNode::hasAnyUseOfValue(unsigned int) const <snip>/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:7270:3 #2 ... in llvm::SDValue::use_empty() const <snip> include/llvm/CodeGen/SelectionDAGNodes.h:1042:17 #3 ... in (anonymous namespace)::DAGCombiner::MergeConsecutiveStores(llvm::StoreSDNode*) <snip>/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:12944:7 Reviewers: niravd Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D33081 llvm-svn: 302746
* [SDAG] Relax conditions under stores of loaded values can be mergedNirav Dave2017-05-101-10/+22
| | | | | | | | | | | | | | | | | | | | | | | | Summary: Allow consecutive stores whose values come from consecutive loads to merged in the presense of other uses of the loads. Previously this was disallowed as in general the merged load cannot be shared with the other uses. Merging N stores into 1 may cause as many as N redundant loads. However in the context of caching this should have neglible affect on memory pressure and reduce instruction count making it almost always a win. Fixes PR32086. Reviewers: spatel, jyknight, andreadb, hfinkel, efriedma Reviewed By: efriedma Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D30471 llvm-svn: 302712
* Small refactoring in DAGCombine. NFCAmaury Sechet2017-05-101-3/+3
| | | | llvm-svn: 302699
* [DAGCombiner] Dropped explicit (sra 0, x) -> 0 and (sra -1, x) -> 0 folds.Simon Pilgrim2017-05-101-6/+2
| | | | | | These are both handled (and tested) by the earlier ComputeNumSignBits == EltSizeInBits fold. llvm-svn: 302651
* [DAGCombiner] Add vector support to fold (shl/srl 0, x) -> 0Simon Pilgrim2017-05-101-2/+2
| | | | llvm-svn: 302641
* [CodeGen] Don't require AA in SDAGISel at -O0.Ahmed Bougacha2017-05-104-27/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | Before r247167, the pass manager builder controlled which AA implementations were used, exporting them all in the AliasAnalysis analysis group. Now, AAResultsWrapperPass always uses BasicAA, but still uses other AA implementations if made available in the pass pipeline. But regardless, SDAGISel is required at O0, and really doesn't need to be doing fancy optimizations based on useful AA results. Don't require AA at CodeGenOpt::None, and only use it otherwise. This does have a functional impact (and one testcase is pessimized because we can't reuse a load). But I think that's desirable no matter what. Note that this alone doesn't result in less DT computations: TwoAddress was previously able to reuse the DT we computed for SDAG. That will be fixed separately. Differential Revision: https://reviews.llvm.org/D32766 llvm-svn: 302611
* DAGCombine: Combine shuffles of splat-shufflesZvi Rackover2017-05-091-0/+54
| | | | | | | | | | | | | | Summary: Reapply r299047, but this time handle correctly splat-masks with undef elements. Reviewers: spatel, RKSimon, eli.friedman, andreadb Reviewed By: spatel Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D31961 llvm-svn: 302583
* Re-land "Use the frame index side table for byval and inalloca arguments"Reid Kleckner2017-05-094-41/+68
| | | | | | This re-lands r302483. It was not the cause of PR32977. llvm-svn: 302544
* Re-land "Don't add DBG_VALUE instructions for static allocas in dbg.declare"Reid Kleckner2017-05-091-14/+0
| | | | | | This re-lands commit r302461. It was not the cause of PR32977. llvm-svn: 302543
* Add extra operand to CALLSEQ_START to keep frame part set up previouslySerge Pavlov2017-05-093-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using arguments with attribute inalloca creates problems for verification of machine representation. This attribute instructs the backend that the argument is prepared in stack prior to CALLSEQ_START..CALLSEQ_END sequence (see http://llvm.org/docs/InAlloca.htm for details). Frame size stored in CALLSEQ_START in this case does not count the size of this argument. However CALLSEQ_END still keeps total frame size, as caller can be responsible for cleanup of entire frame. So CALLSEQ_START and CALLSEQ_END keep different frame size and the difference is treated by MachineVerifier as stack error. Currently there is no way to distinguish this case from actual errors. This patch adds additional argument to CALLSEQ_START and its target-specific counterparts to keep size of stack that is set up prior to the call frame sequence. This argument allows MachineVerifier to calculate actual frame size associated with frame setup instruction and correctly process the case of inalloca arguments. The changes made by the patch are: - Frame setup instructions get the second mandatory argument. It affects all targets that use frame pseudo instructions and touched many files although the changes are uniform. - Access to frame properties are implemented using special instructions rather than calls getOperand(N).getImm(). For X86 and ARM such replacement was made previously. - Changes that reflect appearance of additional argument of frame setup instruction. These involve proper instruction initialization and methods that access instruction arguments. - MachineVerifier retrieves frame size using method, which reports sum of frame parts initialized inside frame instruction pair and outside it. The patch implements approach proposed by Quentin Colombet in https://bugs.llvm.org/show_bug.cgi?id=27481#c1. It fixes 9 tests failed with machine verifier enabled and listed in PR27481. Differential Revision: https://reviews.llvm.org/D32394 llvm-svn: 302527
* Introduce experimental generic intrinsics for horizontal vector reductions.Amara Emerson2017-05-096-1/+163
| | | | | | | | | | | | | | - This change allows targets to opt-in to using them instead of the log2 shufflevector algorithm. - The SLP and Loop vectorizers have the common code to do shuffle reductions factored out into LoopUtils, and now have a unified interface for generating reductions regardless of the preference of the target. LoopUtils now uses TTI to determine what kind of reductions the target wants to handle. - For CodeGen, basic legalization support is added. Differential Revision: https://reviews.llvm.org/D30086 llvm-svn: 302514
* Revert "Don't add DBG_VALUE instructions for static allocas in dbg.declare"Reid Kleckner2017-05-091-0/+14
| | | | | | | | | | This reverts commit r302461. It appears to be causing failures compiling gtest with debug info on the Linux sanitizer bot. I was unable to reproduce the failure locally, however. llvm-svn: 302504
* Revert "Use the frame index side table for byval and inalloca arguments"Reid Kleckner2017-05-094-68/+41
| | | | | | This reverts r302483 and it's follow up fix. llvm-svn: 302493
* Use the frame index side table for byval and inalloca argumentsReid Kleckner2017-05-084-41/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: For inalloca functions, this is a very common code pattern: %argpack = type <{ i32, i32, i32 }> define void @f(%argpack* inalloca %args) { entry: %a = getelementptr inbounds %argpack, %argpack* %args, i32 0, i32 0 %b = getelementptr inbounds %argpack, %argpack* %args, i32 0, i32 1 %c = getelementptr inbounds %argpack, %argpack* %args, i32 0, i32 2 tail call void @llvm.dbg.declare(metadata i32* %a, ... "a") tail call void @llvm.dbg.declare(metadata i32* %c, ... "b") tail call void @llvm.dbg.declare(metadata i32* %b, ... "c") Even though these GEPs can be simplified to a constant offset from EBP or RSP, we don't do that at -O0, and each GEP is computed into a register. Registers used to compute argument addresses are typically spilled and clobbered very quickly after the initial computation, so live debug variable tracking loses information very quickly if we use DBG_VALUE instructions. This change moves processing of dbg.declare between argument lowering and basic block isel, so that we can ask if an argument has a frame index or not. If the argument lives in a register as is the case for byval arguments on some targets, then we don't put it in the side table and during ISel we emit DBG_VALUE instructions. Reviewers: aprantl Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D32980 llvm-svn: 302483
* Don't add DBG_VALUE instructions for static allocas in dbg.declareReid Kleckner2017-05-081-14/+0
| | | | | | | | | | | | | | | | | | | | | | | Summary: An llvm.dbg.declare of a static alloca is always added to the MachineFunction dbg variable map, so these values are entirely redundant. They survive all the way through codegen to be ignored by DWARF emission. Effectively revert r113967 Two bugpoint-reduced test cases from 2012 broke as a result of this change. Despite my best efforts, I haven't been able to rewrite the test case using dbg.value. I'm not too concerned about the lost coverage because these were reduced from the test-suite, which we still run. Reviewers: aprantl, dblaikie Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D32920 llvm-svn: 302461
* [XRay] Custom event logging intrinsicDean Michael Berris2017-05-082-0/+52
| | | | | | | | | | | | | | | | | | | | This patch introduces an LLVM intrinsic and a target opcode for custom event logging in XRay. Initially, its use case will be to allow users of XRay to log some type of string ("poor man's printf"). The target opcode compiles to a noop sled large enough to enable calling through to a runtime-determined relative function call. At runtime, when X-Ray is enabled, the sled is replaced by compiler-rt with a trampoline to the logic for creating the custom log entries. Future patches will implement the compiler-rt parts and clang-side support for emitting the IR corresponding to this intrinsic. Reviewers: timshen, dberris Subscribers: igorb, pelikan, rSerge, timshen, echristo, dberris, llvm-commits Differential Revision: https://reviews.llvm.org/D27503 llvm-svn: 302405
* [DAGCombiner] If ISD::ABS is legal/custom, use it directly instead of ↵Simon Pilgrim2017-05-061-0/+3
| | | | | | | | | | canonicalizing first. Remove an extra canonicalization step if ISD::ABS is going to be used anyway. Updated x86 abs combine to check that we are lowering from both canonicalizations. llvm-svn: 302337
* Simplify dbg.value handling in SDISel with early returnsReid Kleckner2017-05-051-35/+23
| | | | | | | | | | | | | | No functional change other than improving dbgs logging accuracy on constant dbg values. Previously we would add things like "i32 42" as debug values, and then log that we were dropping the debug info, which is silly. Delete some dead code that was checking for static allocas. This remained after r207165, but served no purpose. Currently, static alloca dbg.values are always sent through the DanglingDebugInfoMap, and are usually made valid the first time the alloca is used. llvm-svn: 302267
* [KnownBits] Add wrapper methods for setting and clear all bits in the ↵Craig Topper2017-05-052-7/+4
| | | | | | | | | | underlying APInts in KnownBits. This adds routines for reseting KnownBits to unknown, making the value all zeros or all ones. It also adds methods for querying if the value is zero, all ones or unknown. Differential Revision: https://reviews.llvm.org/D32637 llvm-svn: 302262
* [DAGCombine] Transform (fadd A, (fmul B, -2.0)) -> (fsub A, (fadd B, B)).Chad Rosier2017-05-041-0/+18
| | | | | | Differential Revision: http://reviews.llvm.org/D32596 llvm-svn: 302153
* Refactoring with range-based for, NFCKrzysztof Parzyszek2017-05-043-119/+94
| | | | | | | | Patch by Wei-Ren Chen. Differential Revision: https://reviews.llvm.org/D32682 llvm-svn: 302148
* [SelectionDAG] Improve known bits support for CTPOP.Craig Topper2017-05-041-1/+4
| | | | | | This is based on the same concept from ValueTracking's version of computeKnownBits. llvm-svn: 302110
* [KnownBits] Add zext, sext, and trunc methods to KnownBitsCraig Topper2017-05-033-44/+22
| | | | | | | | This patch adds zext, sext, and trunc methods to KnownBits and uses them where possible. Differential Revision: https://reviews.llvm.org/D32784 llvm-svn: 302088
* [TargetLowering] use isSubsetOf in SimplifyDemandedBits; NFCISanjay Patel2017-05-031-18/+14
| | | | | | | | | This is the DAG equivalent of https://reviews.llvm.org/D32255 , which will hopefully be committed again. The functionality (preferring a 'not' op) is already here in the DAG, so this is just intended to be a clean-up and performance improvement. llvm-svn: 302087
* [DAGCombine] (addcarry (add|uaddo X, Y), 0, Carry) -> (addcarry X, Y, Carry)Amaury Sechet2017-05-031-0/+19
| | | | | | | | | | | | Summary: Do the transform when the carry isn't used. It's a pattern exposed when legalizing large integers. Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D32755 llvm-svn: 302047
* [PowerPC, DAGCombiner] Fold a << (b % (sizeof(a) * 8)) back to a single ↵Tim Shen2017-05-031-0/+33
| | | | | | | | | | | | | | | | instruction Summary: This is the corresponding llvm change to D28037 to ensure no performance regression. Reviewers: bogner, kbarton, hfinkel, iteratee, echristo Subscribers: nemanjai, llvm-commits Differential Revision: https://reviews.llvm.org/D28329 llvm-svn: 301990
* [DAGCombine] (uaddo X, (addcarry Y, 0, Carry)) -> (addcarry X, Y, Carry)Amaury Sechet2017-05-021-0/+21
| | | | | | | | | | | | Summary: This is a common pattern that arise when legalizing large integers operations. Only do it when Y + 1 cannot overflow as this would change the carry behavior of uaddo . Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D32687 llvm-svn: 301922
* [DAGCombine] (add X, (addcarry Y, 0, Carry)) -> (addcarry X, Y, Carry)Amaury Sechet2017-05-021-0/+5
| | | | | | | | | | Summary: Common pattern when legalizing large integers operations. Similar to D32687, when the carry isn't used. Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer Differential Revision: https://reviews.llvm.org/D32738 llvm-svn: 301919
* [SelectionDAG] Improve support for promotion of <1 x fX> floating point ↵Simon Pilgrim2017-05-023-13/+20
| | | | | | | | | | | | argument types (PR31088) PR31088 demonstrated that we were assuming that only integers require promotion from <1 x iX> types, when in fact float types may require it as well - in this case half floats. This patch adds support for extension/truncation for both integer and float types. Differential Revision: https://reviews.llvm.org/D32391 llvm-svn: 301910
* [DAGCombiner] Improve MatchBswapHword logic (PR31357)Simon Pilgrim2017-05-021-11/+16
| | | | | | | | | | | | The existing code only looks at half of the tree when matching bswap + rol patterns ending in an OR tree (as opposed to a cascade). Patch originally introduced by Jim Lewis. Submitted on the behalf of Dinar Temirbulatov. Differential Revision: https://reviews.llvm.org/D32039 llvm-svn: 301907
* [SelectionDAG] Use known ones to provide a better bound for the known zeros ↵Craig Topper2017-05-011-2/+16
| | | | | | | | | | | | | | for CTTZ/CTLZ operations. This is the SelectionDAG version of D32521. If know where at least one 1 is located in the input to these intrinsics we can place an upper bound on the number of bits needed to represent the count and thus increase the number of known zeros in the output. I think we can also refine this further for CTTZ_UNDEF/CTLZ_UNDEF by assuming that the answer will never be BitWidth. I've left this out for now because it caused other test failures across multiple targets. Usually because of turning ADD into OR based on this new information. I'll fix CTPOP in a future patch. Differential Revision: https://reviews.llvm.org/D32692 llvm-svn: 301806
* Generalize the specialized flag-carrying SDNodes by moving flags into SDNode.Amara Emerson2017-05-016-126/+93
| | | | | | | | This removes BinaryWithFlagsSDNode, and flags are now all passed by value. Differential Revision: https://reviews.llvm.org/D32527 llvm-svn: 301803
* [DAGCombiner] shrink/widen a vselect to match its condition operand size ↵Sanjay Patel2017-04-301-0/+61
| | | | | | | | | | | | | | | | | | | | | | | | | | (PR14657) We discussed shrinking/widening of selects in IR in D26556, and I'll try to get back to that patch eventually. But I'm hoping that this transform is less iffy in the DAG where we can check legality of the select that we want to produce. A few things to note: 1. We can't wait until after legalization and do this generically because (at least in the x86 tests from PR14657), we'll have PACKSS and bitcasts in the pattern. 2. This might benefit more of the SSE codegen if we lifted the legal-or-custom requirement, but that requires a closer look to make sure we don't end up worse. 3. There's a 'vblendv' opportunity that we're missing that results in andn/and/or in some cases. That should be fixed next. 4. I'm assuming that AVX1 offers the worst of all worlds wrt uneven ISA support with multiple legal vector sizes, but if there are other targets like that, we should add more tests. 5. There's a codegen miracle in the multi-BB tests from PR14657 (the gcc auto-vectorization tests): despite IR that is terrible for the target, this patch allows us to generate the optimal loop code because something post-ISEL is hoisting the splat extends above the vector loops. Differential Revision: https://reviews.llvm.org/D32620 llvm-svn: 301781
* Do not legalize large add with addc/adde, introduce addcarry and do it with ↵Amaury Sechet2017-04-305-37/+185
| | | | | | | | | | | | | | uaddo/addcarry Summary: As per discution on how to get better codegen an large int legalization, it became clear that using a glue for the carry was preventing several desirable optimizations. Passing the carry down as a value allow for more flexibility. Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer Subscribers: igorb, llvm-commits Differential Revision: https://reviews.llvm.org/D29872 llvm-svn: 301775
* [APInt] Replace calls to setBits with more specific calls to setBitsFrom and ↵Craig Topper2017-04-301-1/+1
| | | | | | setLowBits where possible. llvm-svn: 301768
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