summaryrefslogtreecommitdiffstats
path: root/llvm/test/Analysis/GlobalsModRef
Commit message (Collapse)AuthorAgeFilesLines
* Remove commented out CHECK-NEXT to try and appease ↵Simon Pilgrim2019-11-131-1/+0
| | | | llvm-clang-x86_64-expensive-checks-win buildbot
* [GlobalsAA] Reenable test.Alina Sbirlea2019-11-121-3/+1
|
* Temporarily disable test.Alina Sbirlea2019-11-121-0/+2
|
* [GlobalsAA] Restrict ModRef result if any internal method has its address taken.Alina Sbirlea2019-11-123-0/+147
| | | | | | | | | | | | | Summary: If there are any internal methods whose address was taken, conclude there is nothing known in relation of any other internal method and a global. Reviewers: nlopes, sanjoy.google Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D69690
* [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.Shiva Chen2018-05-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to set breakpoints on labels and list source code around labels, we need collect debug information for labels, i.e., label name, the function label belong, line number in the file, and the address label located. In order to keep these information in LLVM IR and to allow backend to generate debug information correctly. We create a new kind of metadata for labels, DILabel. The format of DILabel is !DILabel(scope: !1, name: "foo", file: !2, line: 3) We hope to keep debug information as much as possible even the code is optimized. So, we create a new kind of intrinsic for label metadata to avoid the metadata is eliminated with basic block. The intrinsic will keep existing if we keep it from optimized out. The format of the intrinsic is llvm.dbg.label(metadata !1) It has only one argument, that is the DILabel metadata. The intrinsic will follow the label immediately. Backend could get the label metadata through the intrinsic's parameter. We also create DIBuilder API for labels to be used by Frontend. Frontend could use createLabel() to allocate DILabel objects, and use insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR. Differential Revision: https://reviews.llvm.org/D45024 Patch by Hsiangkai Wang. llvm-svn: 331841
* Remove alignment argument from memcpy/memmove/memset in favour of alignment ↵Daniel Neilson2018-01-194-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | attributes (Step 1) Summary: This is a resurrection of work first proposed and discussed in Aug 2015: http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.html and initially landed (but then backed out) in Nov 2015: http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html The @llvm.memcpy/memmove/memset intrinsics currently have an explicit argument which is required to be a constant integer. It represents the alignment of the dest (and source), and so must be the minimum of the actual alignment of the two. This change is the first in a series that allows source and dest to each have their own alignments by using the alignment attribute on their arguments. In this change we: 1) Remove the alignment argument. 2) Add alignment attributes to the source & dest arguments. We, temporarily, require that the alignments for source & dest be equal. For example, code which used to read: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 100, i32 4, i1 false) will now read call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 4 %dest, i8* align 4 %src, i32 100, i1 false) Downstream users may have to update their lit tests that check for @llvm.memcpy/memmove/memset call/declaration patterns. The following extended sed script may help with updating the majority of your tests, but it does not catch all possible patterns so some manual checking and updating will be required. s~declare void @llvm\.mem(set|cpy|move)\.p([^(]*)\((.*), i32, i1\)~declare void @llvm.mem\1.p\2(\3, i1)~g s~call void @llvm\.memset\.p([^(]*)i8\(i8([^*]*)\* (.*), i8 (.*), i8 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i8(i8\2* \3, i8 \4, i8 \5, i1 \6)~g s~call void @llvm\.memset\.p([^(]*)i16\(i8([^*]*)\* (.*), i8 (.*), i16 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i16(i8\2* \3, i8 \4, i16 \5, i1 \6)~g s~call void @llvm\.memset\.p([^(]*)i32\(i8([^*]*)\* (.*), i8 (.*), i32 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i32(i8\2* \3, i8 \4, i32 \5, i1 \6)~g s~call void @llvm\.memset\.p([^(]*)i64\(i8([^*]*)\* (.*), i8 (.*), i64 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i64(i8\2* \3, i8 \4, i64 \5, i1 \6)~g s~call void @llvm\.memset\.p([^(]*)i128\(i8([^*]*)\* (.*), i8 (.*), i128 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i128(i8\2* \3, i8 \4, i128 \5, i1 \6)~g s~call void @llvm\.memset\.p([^(]*)i8\(i8([^*]*)\* (.*), i8 (.*), i8 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i8(i8\2* align \6 \3, i8 \4, i8 \5, i1 \7)~g s~call void @llvm\.memset\.p([^(]*)i16\(i8([^*]*)\* (.*), i8 (.*), i16 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i16(i8\2* align \6 \3, i8 \4, i16 \5, i1 \7)~g s~call void @llvm\.memset\.p([^(]*)i32\(i8([^*]*)\* (.*), i8 (.*), i32 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i32(i8\2* align \6 \3, i8 \4, i32 \5, i1 \7)~g s~call void @llvm\.memset\.p([^(]*)i64\(i8([^*]*)\* (.*), i8 (.*), i64 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i64(i8\2* align \6 \3, i8 \4, i64 \5, i1 \7)~g s~call void @llvm\.memset\.p([^(]*)i128\(i8([^*]*)\* (.*), i8 (.*), i128 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i128(i8\2* align \6 \3, i8 \4, i128 \5, i1 \7)~g s~call void @llvm\.mem(cpy|move)\.p([^(]*)i8\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i8 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i8(i8\3* \4, i8\5* \6, i8 \7, i1 \8)~g s~call void @llvm\.mem(cpy|move)\.p([^(]*)i16\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i16 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i16(i8\3* \4, i8\5* \6, i16 \7, i1 \8)~g s~call void @llvm\.mem(cpy|move)\.p([^(]*)i32\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i32 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i32(i8\3* \4, i8\5* \6, i32 \7, i1 \8)~g s~call void @llvm\.mem(cpy|move)\.p([^(]*)i64\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i64 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i64(i8\3* \4, i8\5* \6, i64 \7, i1 \8)~g s~call void @llvm\.mem(cpy|move)\.p([^(]*)i128\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i128 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i128(i8\3* \4, i8\5* \6, i128 \7, i1 \8)~g s~call void @llvm\.mem(cpy|move)\.p([^(]*)i8\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i8 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i8(i8\3* align \8 \4, i8\5* align \8 \6, i8 \7, i1 \9)~g s~call void @llvm\.mem(cpy|move)\.p([^(]*)i16\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i16 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i16(i8\3* align \8 \4, i8\5* align \8 \6, i16 \7, i1 \9)~g s~call void @llvm\.mem(cpy|move)\.p([^(]*)i32\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i32 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i32(i8\3* align \8 \4, i8\5* align \8 \6, i32 \7, i1 \9)~g s~call void @llvm\.mem(cpy|move)\.p([^(]*)i64\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i64 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i64(i8\3* align \8 \4, i8\5* align \8 \6, i64 \7, i1 \9)~g s~call void @llvm\.mem(cpy|move)\.p([^(]*)i128\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i128 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i128(i8\3* align \8 \4, i8\5* align \8 \6, i128 \7, i1 \9)~g The remaining changes in the series will: Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing source and dest alignments. Step 3) Update Clang to use the new IRBuilder API. Step 4) Update Polly to use the new IRBuilder API. Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API, and those that use use MemIntrinsicInst::[get|set]Alignment() to use getDestAlignment() and getSourceAlignment() instead. Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the MemIntrinsicInst::[get|set]Alignment() methods. Reviewers: pete, hfinkel, lhames, reames, bollu Reviewed By: reames Subscribers: niosHD, reames, jholewinski, qcolombet, jfb, sanjoy, arsenm, dschuff, dylanmckay, mehdi_amini, sdardis, nemanjai, david2050, nhaehnle, javed.absar, sbc100, jgravelle-google, eraman, aheejin, kbarton, JDevlieghere, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, llvm-commits Differential Revision: https://reviews.llvm.org/D41675 llvm-svn: 322965
* [GlobalsAA] Don't let dbg intrinsics affect analysis resultMikael Holmen2018-01-151-0/+57
| | | | | | | | | | | | | | | | | | Summary: This fixes PR35899. Debug info intrinsics shouldn't affect code generation so ignore them in GlobalsAA. Reviewers: hfinkel, aprantl Reviewed By: aprantl Subscribers: aprantl, llvm-commits Differential Revision: https://reviews.llvm.org/D41984 llvm-svn: 322470
* [PassManager] Retire cl::opt that have been set for a while. NFCI.Davide Italiano2017-10-023-3/+3
| | | | llvm-svn: 314740
* Move the stripping of invalid debug info from the Verifier to AutoUpgrade.Adrian Prantl2017-10-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | This came out of a recent discussion on llvm-dev (https://reviews.llvm.org/D38042). Currently the Verifier will strip the debug info metadata from a module if it finds the dbeug info to be malformed. This feature is very valuable since it allows us to improve the Verifier by making it stricter without breaking bcompatibility, but arguable the Verifier pass should not be modifying the IR. This patch moves the stripping of broken debug info into AutoUpgrade (UpgradeDebugInfo to be precise), which is a much better location for this since the stripping of malformed (i.e., produced by older, buggy versions of Clang) is a (harsh) form of AutoUpgrade. This change is mostly NFC in nature, the one big difference is the behavior when LLVM module passes are introducing malformed debug info. Prior to this patch, a NoAsserts build would have printed a warning and stripped the debug info, after this patch the Verifier will report a fatal error. I believe this behavior is actually more desirable anyway. Differential Revision: https://reviews.llvm.org/D38184 llvm-svn: 314699
* Fix regression from my recent GlobalsAA fix.Eli Friedman2016-10-241-0/+54
| | | | | | | | | | | | | There are two fixes here: one, AnalyzeUsesOfPointer can't return false until it has checked all the uses of the pointer. Two, if a global uses another global, we have to assume the address of the first global escapes. Fixes https://llvm.org/bugs/show_bug.cgi?id=30707 . Differential Revision: https://reviews.llvm.org/D25798 llvm-svn: 285034
* Make GlobalsAA ignore dead constant expressions.Eli Friedman2016-10-041-0/+54
| | | | | | | | | Slightly improves the precision of GlobalsAA in certain situations, and makes the behavior of optimization passes more predictable. Differential Revision: https://reviews.llvm.org/D24104 llvm-svn: 283165
* [DSE] Don't remove stores made live by a call which unwinds.Eli Friedman2016-08-121-12/+12
| | | | | | | | | | Issue exposed by noalias or more aggressive alias analysis. Fixes http://llvm.org/PR25422. Differential revision: https://reviews.llvm.org/D21007 llvm-svn: 278451
* GlobalsAA: Functions with the argmemonly attribute won't read arbitrary globalsTom Stellard2016-07-141-0/+31
| | | | | | | | | | | | | | | | | Summary: In preparation for changing GlobalsAA to stop assuming that intrinsics can't read arbitrary globals, we need to make sure GlobalsAA is querying function attributes rather than relying on this assumption. This patch was inspired by: http://reviews.llvm.org/D20206 Reviewers: jmolloy, hfinkel Subscribers: eli.friedman, llvm-commits Differential Revision: https://reviews.llvm.org/D21318 llvm-svn: 275433
* Don't IPO over functions that can be de-refinedSanjoy Das2016-04-081-0/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Fixes PR26774. If you're aware of the issue, feel free to skip the "Motivation" section and jump directly to "This patch". Motivation: I define "refinement" as discarding behaviors from a program that the optimizer has license to discard. So transforming: ``` void f(unsigned x) { unsigned t = 5 / x; (void)t; } ``` to ``` void f(unsigned x) { } ``` is refinement, since the behavior went from "if x == 0 then undefined else nothing" to "nothing" (the optimizer has license to discard undefined behavior). Refinement is a fundamental aspect of many mid-level optimizations done by LLVM. For instance, transforming `x == (x + 1)` to `false` also involves refinement since the expression's value went from "if x is `undef` then { `true` or `false` } else { `false` }" to "`false`" (by definition, the optimizer has license to fold `undef` to any non-`undef` value). Unfortunately, refinement implies that the optimizer cannot assume that the implementation of a function it can see has all of the behavior an unoptimized or a differently optimized version of the same function can have. This is a problem for functions with comdat linkage, where a function can be replaced by an unoptimized or a differently optimized version of the same source level function. For instance, FunctionAttrs cannot assume a comdat function is actually `readnone` even if it does not have any loads or stores in it; since there may have been loads and stores in the "original function" that were refined out in the currently visible variant, and at the link step the linker may in fact choose an implementation with a load or a store. As an example, consider a function that does two atomic loads from the same memory location, and writes to memory only if the two values are not equal. The optimizer is allowed to refine this function by first CSE'ing the two loads, and the folding the comparision to always report that the two values are equal. Such a refined variant will look like it is `readonly`. However, the unoptimized version of the function can still write to memory (since the two loads //can// result in different values), and selecting the unoptimized version at link time will retroactively invalidate transforms we may have done under the assumption that the function does not write to memory. Note: this is not just a problem with atomics or with linking differently optimized object files. See PR26774 for more realistic examples that involved neither. This patch: This change introduces a new set of linkage types, predicated as `GlobalValue::mayBeDerefined` that returns true if the linkage type allows a function to be replaced by a differently optimized variant at link time. It then changes a set of IPO passes to bail out if they see such a function. Reviewers: chandlerc, hfinkel, dexonsmith, joker.eph, rnk Subscribers: mcrosier, llvm-commits Differential Revision: http://reviews.llvm.org/D18634 llvm-svn: 265762
* [PM/AA] Teach the AAManager how to handle module analyses in addition toChandler Carruth2016-03-112-0/+2
| | | | | | | function analyses, and use it to wire up globals-aa to the new pass manager. llvm-svn: 263211
* [GlobalsAA] Relax condition in checking globals as args to functionsVaivaswatha Nagaraj2016-01-141-0/+65
| | | | | | | | | | | | | | | | | Summary: Since globals may escape as function arguments (even when they have been found to be non-escaping, because of optimizations such as memcpyoptimizer that replaces stores with memcpy), all arguments to a function are checked during query to make sure they are identifiable. At that time, also ensure we return a conservative result only if the arguments don't alias to our global. Reviewers: hfinkel, jmolloy Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D16140 llvm-svn: 257750
* [GlobalsAA] Partially back out r248576James Molloy2016-01-071-57/+0
| | | | | | | | | | | | | | | | | | | See PR25822 for a more full summary, but we were conflating the concepts of "capture" and "escape". We were proving nocapture and using that proof to infer noescape, which is not true. Escaped-ness is a function-local property - as soon as a value is used in a call argument it escapes. Capturedness is a related but distinct property. It implies a *temporally limited* escape. Consider: static int a; int b; int g(int * nocapture arg); int f() { a = 2; // Even though a escapes to g, it is not captured so can be treated as non-escaping here. g(&a); // But here it must be treated as escaping. g(&b); // Now that g(&a) has returned we know it was not captured so we can treat it as non-escaping again. } The original commit did not sufficiently understand this nuance and so caused PR25822 and PR26046. r248576 included both a performance improvement (which has been backed out) and a related conformance fix (which has been kept along with its testcase). llvm-svn: 257058
* Revert "GlobalsAA: Take advantage of ArgMemOnly, InaccessibleMemOnly and ↵Amaury Sechet2016-01-063-67/+21
| | | | | | | | | | | | | | | | | | | InaccessibleMemOrArgMemOnly attributes" Summary: This reverts commit 5a9e526f29cf8510ab5c3d566fbdcf47ac24e1e9. As per discussion in D15665 This also add a test case so that regression introduced by that diff are not reintroduced. Reviewers: vaivaswatha, jmolloy, hfinkel, reames Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D15919 llvm-svn: 256932
* [OperandBundles] Have GlobalsModRef play nice with operand bundlesDavid Majnemer2015-12-231-1/+11
| | | | | | | A call site's use of a Value might not correspond to an argument operand but to a bundle operand. llvm-svn: 256329
* GlobalsAA: Take advantage of ArgMemOnly, InaccessibleMemOnly and ↵Vaivaswatha Nagaraj2015-12-182-0/+67
| | | | | | | | | | | | | | | | | | | | | InaccessibleMemOrArgMemOnly attributes Summary: 1. Modify AnalyzeCallGraph() to retain function info for external functions if the function has [InaccessibleMemOr]ArgMemOnly flags. 2. When analyzing the use of a global is function parameter at a call site, mark the callee also as modifying the global appropriately. 3. Add additional test cases. Depends on D15499 Reviewers: hfinkel, jmolloy Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D15605 llvm-svn: 255994
* Revert "Change memcpy/memset/memmove to have dest and source alignments."Pete Cooper2015-11-192-5/+5
| | | | | | | | | | This reverts commit r253511. This likely broke the bots in http://lab.llvm.org:8011/builders/clang-ppc64-elf-linux2/builds/20202 http://bb.pgr.jp/builders/clang-3stage-i686-linux/builds/3787 llvm-svn: 253543
* Change memcpy/memset/memmove to have dest and source alignments.Pete Cooper2015-11-182-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html These intrinsics currently have an explicit alignment argument which is required to be a constant integer. It represents the alignment of the source and dest, and so must be the minimum of those. This change allows source and dest to each have their own alignments by using the alignment attribute on their arguments. The alignment argument itself is removed. There are a few places in the code for which the code needs to be checked by an expert as to whether using only src/dest alignment is safe. For those places, they currently take the minimum of src/dest alignments which matches the current behaviour. For example, code which used to read: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false) will now read: call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 8 %dest, i8* align 8 %src, i32 500, i1 false) For out of tree owners, I was able to strip alignment from calls using sed by replacing: (call.*llvm\.memset.*)i32\ [0-9]*\,\ i1 false\) with: $1i1 false) and similarly for memmove and memcpy. I then added back in alignment to test cases which needed it. A similar commit will be made to clang which actually has many differences in alignment as now IRBuilder can generate different source/dest alignments on calls. In IRBuilder itself, a new argument was added. Instead of calling: CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, /* isVolatile */ false) you now call CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, SrcAlign, /* isVolatile */ false) There is a temporary class (IntegerAlignment) which takes the source alignment and rejects implicit conversion from bool. This is to prevent isVolatile here from passing its default parameter to the source alignment. Note, changes in future can now be made to codegen. I didn't change anything here, but this change should enable better memcpy code sequences. Reviewed by Hal Finkel. llvm-svn: 253511
* Add newline to test. NFC.Chad Rosier2015-10-281-1/+1
| | | | llvm-svn: 251511
* [GlobalsAA] An indirect global that is initialized is not fair gameJames Molloy2015-10-281-0/+27
| | | | | | | | When checking if an indirect global (a global with pointer type) is only assigned by allocation functions, first check if the global is itself initialized. If it is, it's not only assigned by allocation functions. This fixes PR25309. Thanks to David Majnemer for reducing the test case! llvm-svn: 251508
* [GlobalsAA] Loosen an overly conservative bailoutJames Molloy2015-10-221-0/+17
| | | | | | | | | | Instead of bailing out when we see loads, analyze them. If we can prove that the loaded-from address must escape, then we can conclude that a load from that address must escape too and therefore cannot alias a non-addr-taken global. When checking if a Value can alias a non-addr-taken global, if the Value is a LoadInst of a non-global, recurse instead of bailing. If we can follow a trail of loads up to some base that is captured, we know by inference that all the loads we followed are also captured. llvm-svn: 251017
* [GlobalsAA] Don't assume anything about functions that may be overriddenJames Molloy2015-10-131-0/+24
| | | | | | | | Weak linkage and friends allow a symbol to be overriden outside the code generator's model, so GlobalsAA shouldn't assume that anything it can compute about such a symbol is valid. llvm-svn: 250156
* [GlobalsAA] Teach GlobalsAA about nocaptureJames Molloy2015-09-252-0/+112
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Arguments to function calls marked "nocapture" can be marked as non-escaping. However, nocapture is defined in terms of the lifetime of the callee, and if the callee can directly or indirectly recurse to the caller, the semantics of nocapture are invalid. Therefore, we eagerly discover which SCC each function belongs to, and later can check if callee and caller of a callsite belong to the same SCC, in which case there could be recursion. This means that we can't be so optimistic in getModRefInfo(ImmutableCallsite) - previously we assumed all call arguments never aliased with an escaping global. Now we need to check, because a global could now be passed as an argument but still not escape. This also solves a related conformance problem: MemCpyOptimizer can turn non-escaping stores of globals into calls to intrinsics like llvm.memcpy/llvm/memset. This confuses GlobalsAA, which knows the global can't escape and so returns NoModRef when queried, when obviously a memcpy/memset call does indeed reference and modify its arguments. This fixes PR24800, PR24801, and PR24802. llvm-svn: 248576
* [PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatibleChandler Carruth2015-09-099-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | with the new pass manager, and no longer relying on analysis groups. This builds essentially a ground-up new AA infrastructure stack for LLVM. The core ideas are the same that are used throughout the new pass manager: type erased polymorphism and direct composition. The design is as follows: - FunctionAAResults is a type-erasing alias analysis results aggregation interface to walk a single query across a range of results from different alias analyses. Currently this is function-specific as we always assume that aliasing queries are *within* a function. - AAResultBase is a CRTP utility providing stub implementations of various parts of the alias analysis result concept, notably in several cases in terms of other more general parts of the interface. This can be used to implement only a narrow part of the interface rather than the entire interface. This isn't really ideal, this logic should be hoisted into FunctionAAResults as currently it will cause a significant amount of redundant work, but it faithfully models the behavior of the prior infrastructure. - All the alias analysis passes are ported to be wrapper passes for the legacy PM and new-style analysis passes for the new PM with a shared result object. In some cases (most notably CFL), this is an extremely naive approach that we should revisit when we can specialize for the new pass manager. - BasicAA has been restructured to reflect that it is much more fundamentally a function analysis because it uses dominator trees and loop info that need to be constructed for each function. All of the references to getting alias analysis results have been updated to use the new aggregation interface. All the preservation and other pass management code has been updated accordingly. The way the FunctionAAResultsWrapperPass works is to detect the available alias analyses when run, and add them to the results object. This means that we should be able to continue to respect when various passes are added to the pipeline, for example adding CFL or adding TBAA passes should just cause their results to be available and to get folded into this. The exception to this rule is BasicAA which really needs to be a function pass due to using dominator trees and loop info. As a consequence, the FunctionAAResultsWrapperPass directly depends on BasicAA and always includes it in the aggregation. This has significant implications for preserving analyses. Generally, most passes shouldn't bother preserving FunctionAAResultsWrapperPass because rebuilding the results just updates the set of known AA passes. The exception to this rule are LoopPass instances which need to preserve all the function analyses that the loop pass manager will end up needing. This means preserving both BasicAAWrapperPass and the aggregating FunctionAAResultsWrapperPass. Now, when preserving an alias analysis, you do so by directly preserving that analysis. This is only necessary for non-immutable-pass-provided alias analyses though, and there are only three of interest: BasicAA, GlobalsAA (formerly GlobalsModRef), and SCEVAA. Usually BasicAA is preserved when needed because it (like DominatorTree and LoopInfo) is marked as a CFG-only pass. I've expanded GlobalsAA into the preserved set everywhere we previously were preserving all of AliasAnalysis, and I've added SCEVAA in the intersection of that with where we preserve SCEV itself. One significant challenge to all of this is that the CGSCC passes were actually using the alias analysis implementations by taking advantage of a pretty amazing set of loop holes in the old pass manager's analysis management code which allowed analysis groups to slide through in many cases. Moving away from analysis groups makes this problem much more obvious. To fix it, I've leveraged the flexibility the design of the new PM components provides to just directly construct the relevant alias analyses for the relevant functions in the IPO passes that need them. This is a bit hacky, but should go away with the new pass manager, and is already in many ways cleaner than the prior state. Another significant challenge is that various facilities of the old alias analysis infrastructure just don't fit any more. The most significant of these is the alias analysis 'counter' pass. That pass relied on the ability to snoop on AA queries at different points in the analysis group chain. Instead, I'm planning to build printing functionality directly into the aggregation layer. I've not included that in this patch merely to keep it smaller. Note that all of this needs a nearly complete rewrite of the AA documentation. I'm planning to do that, but I'd like to make sure the new design settles, and to flesh out a bit more of what it looks like in the new pass manager first. Differential Revision: http://reviews.llvm.org/D12080 llvm-svn: 247167
* [GMR] isNonEscapingGlobalNoAlias() should look through Bitcasts/GEPs when ↵Michael Kuperstein2015-08-171-1/+2
| | | | | | | | | | looking at loads. This fixes yet another case from PR24288. Differential Revision: http://reviews.llvm.org/D12064 llvm-svn: 245207
* [GMR] Be a bit smarter about which globals don't alias when doing recursive ↵Michael Kuperstein2015-08-111-4/+7
| | | | | | | | | | lookups Should hopefully fix the remainder of PR24288. Differential Revision: http://reviews.llvm.org/D11900 llvm-svn: 244575
* [GMR] Teach the conservative path of GMR to catch even more easy cases.Chandler Carruth2015-08-051-0/+33
| | | | | | | | | | | | | | In PR24288 it was pointed out that the easy case of a non-escaping global and something that *obviously* required an escape sometimes is hidden behind PHIs (or selects in theory). Because we have this binary test, we can easily just check that all possible input values satisfy the requirement. This is done with a (very small) recursion through PHIs and selects. With this, the specific example from the PR is correctly folded by GVN. Differential Revision: http://reviews.llvm.org/D11707 llvm-svn: 244078
* [GMR] Teach GlobalsModRef to distinguish an important and safe case ofChandler Carruth2015-07-281-0/+62
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | no-alias with non-addr-taken globals: they cannot alias a captured pointer. If the non-global underlying object would have been a capture were it to alias the global, we can firmly conclude no-alias. It isn't reasonable for a transformation to introduce a capture in a way observable by an alias analysis. Consider, even if it were to temporarily capture one globals address into another global and then restore the other global afterward, there would be no way for the load in the alias query to observe that capture event correctly. If it observes it then the temporary capturing would have changed the meaning of the program, making it an invalid transformation. Even instrumentation passes or a pass which is synthesizing stores to global variables to expose race conditions in programs could not trigger this unless it queried the alias analysis infrastructure mid-transform, in which case it seems reasonable to return results from before the transform started. See the comments in the change for a more detailed outlining of the theory here. This should address the primary performance regression found when the non-conservatively-correct path of the alias query was disabled. Differential Revision: http://reviews.llvm.org/D11410 llvm-svn: 243405
* [PM/AA] Disable the core unsafe aspect of GlobalsModRef in the face ofChandler Carruth2015-07-172-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | basic changes to the IR such as folding pointers through PHIs, Selects, integer casts, store/load pairs, or outlining. This leaves the feature available behind a flag. This flag's default could be flipped if necessary, but the real-world performance impact of this particular feature of GMR may not be sufficiently significant for many folks to want to run the risk. Currently, the risk here is somewhat mitigated by half-hearted attempts to update GlobalsModRef when the rest of the optimizer changes something. However, I am currently trying to remove that update mechanism as it makes migrating the AA infrastructure to a form that can be readily shared between new and old pass managers very challenging. Without this update mechanism, it is possible that this still unlikely failure mode will start to trip people, and so I wanted to try to proactively avoid that. There is a lengthy discussion on the mailing list about why the core approach here is flawed, and likely would need to look totally different to be both reasonably effective and resilient to basic IR changes occuring. This patch is essentially the first of two which will enact the result of that discussion. The next patch will remove the current update mechanism. Thanks to lots of folks that helped look at this from different angles. Especial thanks to Michael Zolotukhin for doing some very prelimanary benchmarking of LTO without GlobalsModRef to get a rough idea of the impact we could be facing here. So far, it looks very small, but there are some concerns lingering from other benchmarking. The default here may get flipped if performance results end up pointing at this as a more significant issue. Also thanks to Pete and Gerolf for reviewing! Differential Revision: http://reviews.llvm.org/D11213 llvm-svn: 242512
* Add a test for r242281 from an old patch of mine.Sean Silva2015-07-151-0/+37
| | | | | | This isn't thorough, but should serve as a sanity check. llvm-svn: 242356
* [opaque pointer type] Add textual IR support for explicit type parameter to ↵David Blaikie2015-04-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | the call instruction See r230786 and r230794 for similar changes to gep and load respectively. Call is a bit different because it often doesn't have a single explicit type - usually the type is deduced from the arguments, and just the return type is explicit. In those cases there's no need to change the IR. When that's not the case, the IR usually contains the pointer type of the first operand - but since typed pointers are going away, that representation is insufficient so I'm just stripping the "pointerness" of the explicit type away. This does make the IR a bit weird - it /sort of/ reads like the type of the first operand: "call void () %x(" but %x is actually of type "void ()*" and will eventually be just of type "ptr". But this seems not too bad and I don't think it would benefit from repeating the type ("void (), void () * %x(" and then eventually "void (), ptr %x(") as has been done with gep and load. This also has a side benefit: since the explicit type is no longer a pointer, there's no ambiguity between an explicit type and a function that returns a function pointer. Previously this case needed an explicit type (eg: a function returning a void() function was written as "call void () () * @x(" rather than "call void () * @x(" because of the ambiguity between a function returning a pointer to a void() function and a function returning void). No ambiguity means even function pointer return types can just be written alone, without writing the whole function's type. This leaves /only/ the varargs case where the explicit type is required. Given the special type syntax in call instructions, the regex-fu used for migration was a bit more involved in its own unique way (as every one of these is) so here it is. Use it in conjunction with the apply.sh script and associated find/xargs commands I've provided in rr230786 to migrate your out of tree tests. Do let me know if any of this doesn't cover your cases & we can iterate on a more general script/regexes to help others with out of tree tests. About 9 test cases couldn't be automatically migrated - half of those were functions returning function pointers, where I just had to manually delete the function argument types now that we didn't need an explicit function type there. The other half were typedefs of function types used in calls - just had to manually drop the * from those. import fileinput import sys import re pat = re.compile(r'((?:=|:|^|\s)call\s(?:[^@]*?))(\s*$|\s*(?:(?:\[\[[a-zA-Z0-9_]+\]\]|[@%](?:(")?[\\\?@a-zA-Z0-9_.]*?(?(3)"|)|{{.*}}))(?:\(|$)|undef|inttoptr|bitcast|null|asm).*$)') addrspace_end = re.compile(r"addrspace\(\d+\)\s*\*$") func_end = re.compile("(?:void.*|\)\s*)\*$") def conv(match, line): if not match or re.search(addrspace_end, match.group(1)) or not re.search(func_end, match.group(1)): return line return line[:match.start()] + match.group(1)[:match.group(1).rfind('*')].rstrip() + match.group(2) + line[match.end():] for line in sys.stdin: sys.stdout.write(conv(re.search(pat, line), line)) llvm-svn: 235145
* [opaque pointer type] Add textual IR support for explicit type parameter to ↵David Blaikie2015-03-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | gep operator Similar to gep (r230786) and load (r230794) changes. Similar migration script can be used to update test cases, which successfully migrated all of LLVM and Polly, but about 4 test cases needed manually changes in Clang. (this script will read the contents of stdin and massage it into stdout - wrap it in the 'apply.sh' script shown in previous commits + xargs to apply it over a large set of test cases) import fileinput import sys import re rep = re.compile(r"(getelementptr(?:\s+inbounds)?\s*\()((<\d*\s+x\s+)?([^@]*?)(|\s*addrspace\(\d+\))\s*\*(?(3)>)\s*)(?=$|%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|zeroinitializer|<|\[\[[a-zA-Z]|\{\{)", re.MULTILINE | re.DOTALL) def conv(match): line = match.group(1) line += match.group(4) line += ", " line += match.group(2) return line line = sys.stdin.read() off = 0 for match in re.finditer(rep, line): sys.stdout.write(line[off:match.start()]) sys.stdout.write(conv(match)) off = match.end() sys.stdout.write(line[off:]) llvm-svn: 232184
* [opaque pointer type] Add textual IR support for explicit type parameter to ↵David Blaikie2015-02-277-12/+12
| | | | | | | | | | | | | | | | | | | | | | | | load instruction Essentially the same as the GEP change in r230786. A similar migration script can be used to update test cases, though a few more test case improvements/changes were required this time around: (r229269-r229278) import fileinput import sys import re pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)") for line in sys.stdin: sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line)) Reviewers: rafael, dexonsmith, grosser Differential Revision: http://reviews.llvm.org/D7649 llvm-svn: 230794
* Move the complex address expression out of DIVariable and into an extraAdrian Prantl2014-10-011-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | argument of the llvm.dbg.declare/llvm.dbg.value intrinsics. Previously, DIVariable was a variable-length field that has an optional reference to a Metadata array consisting of a variable number of complex address expressions. In the case of OpPiece expressions this is wasting a lot of storage in IR, because when an aggregate type is, e.g., SROA'd into all of its n individual members, the IR will contain n copies of the DIVariable, all alike, only differing in the complex address reference at the end. By making the complex address into an extra argument of the dbg.value/dbg.declare intrinsics, all of the pieces can reference the same variable and the complex address expressions can be uniqued across the CU, too. Down the road, this will allow us to move other flags, such as "indirection" out of the DIVariable, too. The new intrinsics look like this: declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr) declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr) This patch adds a new LLVM-local tag to DIExpressions, so we can detect and pretty-print DIExpression metadata nodes. What this patch doesn't do: This patch does not touch the "Indirect" field in DIVariable; but moving that into the expression would be a natural next step. http://reviews.llvm.org/D4919 rdar://problem/17994491 Thanks to dblaikie and dexonsmith for reviewing this patch! Note: I accidentally committed a bogus older version of this patch previously. llvm-svn: 218787
* Revert r218778 while investigating buldbot breakage.Adrian Prantl2014-10-011-2/+2
| | | | | | "Move the complex address expression out of DIVariable and into an extra" llvm-svn: 218782
* Move the complex address expression out of DIVariable and into an extraAdrian Prantl2014-10-011-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | argument of the llvm.dbg.declare/llvm.dbg.value intrinsics. Previously, DIVariable was a variable-length field that has an optional reference to a Metadata array consisting of a variable number of complex address expressions. In the case of OpPiece expressions this is wasting a lot of storage in IR, because when an aggregate type is, e.g., SROA'd into all of its n individual members, the IR will contain n copies of the DIVariable, all alike, only differing in the complex address reference at the end. By making the complex address into an extra argument of the dbg.value/dbg.declare intrinsics, all of the pieces can reference the same variable and the complex address expressions can be uniqued across the CU, too. Down the road, this will allow us to move other flags, such as "indirection" out of the DIVariable, too. The new intrinsics look like this: declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr) declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr) This patch adds a new LLVM-local tag to DIExpressions, so we can detect and pretty-print DIExpression metadata nodes. What this patch doesn't do: This patch does not touch the "Indirect" field in DIVariable; but moving that into the expression would be a natural next step. http://reviews.llvm.org/D4919 rdar://problem/17994491 Thanks to dblaikie and dexonsmith for reviewing this patch! llvm-svn: 218778
* BasicAA: Use reachabilty instead of dominance for checking value equality in phiArnold Schwaighofer2014-01-031-1/+1
| | | | | | | | | | | | | | | | | | | | | cycles This allows the value equality check to work even if we don't have a dominator tree. Also add some more comments. I was worried about compile time impacts and did not implement reachability but used the dominance check in the initial patch. The trade-off was that the dominator tree was required. The llvm utility function isPotentiallyReachable cuts off the recursive search after 32 visits. Testing did not show any compile time regressions showing my worries unjustfied. No compile time or performance regressions at O3 -flto -mavx on test-suite + externals. Addresses review comments from r198290. llvm-svn: 198400
* BasicAA: Fix value equality and phi cyclesArnold Schwaighofer2014-01-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | When there are cycles in the value graph we have to be careful interpreting "Value*" identity as "value" equivalence. We interpret the value of a phi node as the value of its operands. When we check for value equivalence now we make sure that the "Value*" dominates all cycles (phis). %0 = phi [%noaliasval, %addr2] %l = load %ptr %addr1 = gep @a, 0, %l %addr2 = gep @a, 0, (%l + 1) store %ptr ... Before this patch we would return NoAlias for (%0, %addr1) which is wrong because the value of the load is from different iterations of the loop. Tested on x86_64 -mavx at O3 and O3 -flto with no performance or compile time regressions. PR18068 radar://15653794 llvm-svn: 198290
* [tests] Cleanup initialization of test suffixes.Daniel Dunbar2013-08-161-1/+0
| | | | | | | | | | | | | | | | | - Instead of setting the suffixes in a bunch of places, just set one master list in the top-level config. We now only modify the suffix list in a few suites that have one particular unique suffix (.ml, .mc, .yaml, .td, .py). - Aside from removing the need for a bunch of lit.local.cfg files, this enables 4 tests that were inadvertently being skipped (one in Transforms/BranchFolding, a .s file each in DebugInfo/AArch64 and CodeGen/PowerPC, and one in CodeGen/SI which is now failing and has been XFAILED). - This commit also fixes a bunch of config files to use config.root instead of older copy-pasted code. llvm-svn: 188513
* TBAA: remove !tbaa from testing cases if not used.Manman Ren2013-04-291-6/+2
| | | | | | | This will make it easier to turn on struct-path aware TBAA since the metadata format will change. llvm-svn: 180743
* MemoryDependenceAnalysis attempts to find the first memory dependency for ↵Nadav Rotem2012-08-131-0/+34
| | | | | | | | | | | function calls. Currently, if GetLocation reports that it did not find a valid pointer (this is the case for volatile load/stores), we ignore the result. This patch adds code to handle the cases where we did not obtain a valid pointer. rdar://11872864 PR12899 llvm-svn: 161802
* FileCheck-ize tests.Bill Wendling2012-04-246-9/+28
| | | | llvm-svn: 155434
* Handle intrinsics in GlobalsModRef. Fixes pr12351.Rafael Espindola2012-03-281-0/+33
| | | | llvm-svn: 153604
* Replace all instances of dg.exp file with lit.local.cfg, since all tests are ↵Eli Bendersky2012-02-162-3/+1
| | | | | | | | run with LIT now and now Dejagnu. dg.exp is no longer needed. Patch reviewed by Daniel Dunbar. It will be followed by additional cleanup patches. llvm-svn: 150664
* manually upgrade a bunch of tests to modern syntax, and remove some thatChris Lattner2011-06-171-1/+4
| | | | | | are either unreduced or only test old syntax. llvm-svn: 133228
* Make BasicAliasAnalysis a normal AliasAnalysis implementation whichDan Gohman2010-10-184-4/+4
| | | | | | | | | | | | does normal initialization and normal chaining. Change the default AliasAnalysis implementation to NoAlias. Update StandardCompileOpts.h and friends to explicitly request BasicAliasAnalysis. Update tests to explicitly request -basicaa. llvm-svn: 116720
OpenPOWER on IntegriCloud