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* [CallSite removal] Migrate all Alias Analysis APIs to use the newlyChandler Carruth2019-01-071-14/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | minted `CallBase` class instead of the `CallSite` wrapper. This moves the largest interwoven collection of APIs that traffic in `CallSite`s. While a handful of these could have been migrated with a minorly more shallow migration by converting from a `CallSite` to a `CallBase`, it hardly seemed worth it. Most of the APIs needed to migrate together because of the complex interplay of AA APIs and the fact that converting from a `CallBase` to a `CallSite` isn't free in its current implementation. Out of tree users of these APIs can fairly reliably migrate with some combination of `.getInstruction()` on the `CallSite` instance and casting the resulting pointer. The most generic form will look like `CS` -> `cast_or_null<CallBase>(CS.getInstruction())` but in most cases there is a more elegant migration. Hopefully, this migrates enough APIs for users to fully move from `CallSite` to the base class. All of the in-tree users were easily migrated in that fashion. Thanks for the review from Saleem! Differential Revision: https://reviews.llvm.org/D55641 llvm-svn: 350503
* [ValueTracking] Fix a misuse of APInt in GetPointerBaseWithConstantOffsetFlorian Hahn2019-01-041-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GetPointerBaseWithConstantOffset include this code, where ByteOffset and GEPOffset are both of type llvm::APInt : ByteOffset += GEPOffset.getSExtValue(); The problem with this line is that getSExtValue() returns an int64_t, but the += matches an overload for uint64_t. The problem is that the resulting APInt is no longer considered to be signed. That in turn causes assertion failures later on if the relevant pointer type is > 64 bits in width and the GEPOffset was negative. Changing it to ByteOffset += GEPOffset.sextOrTrunc(ByteOffset.getBitWidth()); resolves the issue and explicitly performs the sign-extending or truncation. Additionally, instead of asserting later if the result is > 64 bits, it breaks out of the loop in that case. See also https://reviews.llvm.org/D24729 https://reviews.llvm.org/D24772 This commit must be merged after D38662 in order for the test to pass. Patch by Michael Ferguson <mpfergu@gmail.com>. Reviewers: reames, sanjoy, hfinkel Reviewed By: hfinkel Differential Revision: https://reviews.llvm.org/D38501 llvm-svn: 350395
* [IR] Add Instruction::isLifetimeStartOrEnd, NFCVedant Kumar2018-12-211-2/+1
| | | | | | | | | | | Instruction::isLifetimeStartOrEnd() checks whether an Instruction is an llvm.lifetime.start or an llvm.lifetime.end intrinsic. This was suggested as a cleanup in D55967. Differential Revision: https://reviews.llvm.org/D56019 llvm-svn: 349964
* [ValueTracking] remove unused parameters from helper functions; NFCSanjay Patel2018-12-191-23/+16
| | | | llvm-svn: 349641
* [ValueTracking] Support funnel shifts in computeKnownBits()Nikita Popov2018-12-021-0/+21
| | | | | | | | | | | | If the shift amount is known, we can determine the known bits of the output based on the known bits of two inputs. This is essentially the same functionality as implemented in D54869, but for ValueTracking rather than InstCombine SimplifyDemandedBits. Differential Revision: https://reviews.llvm.org/D55140 llvm-svn: 348091
* [ValueTracking] add helper function for testing implied condition; NFCISanjay Patel2018-12-021-0/+32
| | | | | | | | We were duplicating code around the existing isImpliedCondition() that checks for a predecessor block/dominating condition, so make that a wrapper call. llvm-svn: 348088
* [ValueTracking] Determine always-overflow condition for unsigned subNikita Popov2018-11-281-6/+11
| | | | | | | | | | | | Always-overflow was already determined for unsigned addition, but not subtraction. This patch establishes parity. This allows us to perform some additional simplifications for signed saturating subtractions. This change is part of https://reviews.llvm.org/D54534. llvm-svn: 347771
* [ValueTracking] determine sign of 0.0 from select when matching min/max FPSanjay Patel2018-11-041-0/+21
| | | | | | | | | | | | | | | | | | | In PR39475: https://bugs.llvm.org/show_bug.cgi?id=39475 ..we may fail to recognize/simplify fabs() in some cases because we do not canonicalize fcmp with a -0.0 operand. Adding that canonicalization can cause regressions on min/max FP tests, so that's this patch: for the purpose of determining whether something is min/max, let the value returned by the select determine how we treat a 0.0 operand in the fcmp. This patch doesn't actually change the -0.0 to +0.0. It just changes the analysis, so we don't fail to recognize equivalent min/max patterns that only differ in the signbit of 0.0. Differential Revision: https://reviews.llvm.org/D54001 llvm-svn: 346097
* [ValueTracking] peek through 2-input shuffles in ComputeNumSignBitsSanjay Patel2018-11-031-19/+34
| | | | | | | | | | | This patch gives the IR ComputeNumSignBits the same functionality as the DAG version (the code is derived from the existing code). This an extension of the single input shuffle analysis added with D53659. Differential Revision: https://reviews.llvm.org/D53987 llvm-svn: 346071
* [ValueTracking] allow non-canonical shuffles when computing signbitsSanjay Patel2018-11-021-8/+10
| | | | | | | This possibility is noted in D53987 for a different case, so we need to adjust the existing code. llvm-svn: 345988
* [ValueTracking] peek through shuffles in ComputeNumSignBits (PR37549)Sanjay Patel2018-10-261-0/+21
| | | | | | | | | | | | | | | | | The motivating case is from PR37549: https://bugs.llvm.org/show_bug.cgi?id=37549 The analysis improvement allows us to form a vector 'select' out of bitwise logic (the use of ComputeNumSignBits was added at rL345149). The smaller test shows another InstCombine improvement - we use ComputeNumSignBits to add 'nsw' to shift-left. But the negative test shows an example where we must not add 'nsw' - when the shuffle mask contains undef elements. Differential Revision: https://reviews.llvm.org/D53659 llvm-svn: 345429
* [InstCombine] InstCombine and InstSimplify for minimum and maximumThomas Lively2018-10-191-0/+6
| | | | | | | | | | | | Summary: Depends on D52765 Reviewers: aheejin, dschuff Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D52766 llvm-svn: 344799
* [ValueTracking] Allow select patterns to work on FP vectorsThomas Lively2018-09-281-0/+22
| | | | | | | | | | | | | | | | | | | | Summary: This CL allows constant vectors of floats to be recognized as non-NaN and non-zero in select patterns. This change makes `matchSelectPattern` more powerful generally, but was motivated specifically because I wanted fminnan and fmaxnan to be created for vector versions of the scalar patterns they are created for. Tested with check-all on all targets. A testcase in the WebAssembly backend that tests the non-nan codepath is in an upcoming CL. Reviewers: aheejin, dschuff Subscribers: sunfish, llvm-commits Differential Revision: https://reviews.llvm.org/D52324 llvm-svn: 343364
* Merge clang's isRepeatedBytePattern with LLVM's isBytewiseValueJF Bastien2018-09-211-32/+62
| | | | | | | | | | | | | Summary: his code was in CGDecl.cpp and really belongs in LLVM's isBytewiseValue. Teach isBytewiseValue the tricks clang's isRepeatedBytePattern had, including merging undef properly, and recursing on more types. clang part of this patch: D51752 Subscribers: dexonsmith, llvm-commits Differential Revision: https://reviews.llvm.org/D51751 llvm-svn: 342709
* Re-enable "[NFC] Unify guards detection"Max Kazantsev2018-08-301-2/+2
| | | | | | | | | | rL340921 has been reverted by rL340923 due to linkage dependency from Transform/Utils to Analysis which is not allowed. In this patch this has been fixed, a new utility function moved to Analysis. Differential Revision: https://reviews.llvm.org/D51152 llvm-svn: 341014
* Revert r340921 "[NFC] Unify guards detection"Hans Wennborg2018-08-291-2/+2
| | | | | | | | | | | | | | | | | | This broke the build, see e.g. http://lab.llvm.org:8011/builders/clang-cmake-armv8-lnt/builds/4626/ http://lab.llvm.org:8011/builders/clang-ppc64be-linux-lnt/builds/18647/ http://lab.llvm.org:8011/builders/clang-cmake-x86_64-avx2-linux/builds/5856/ http://lab.llvm.org:8011/builders/lld-x86_64-freebsd/builds/22800/ > We have multiple places in code where we try to identify whether or not > some instruction is a guard. This patch factors out this logic into a separate > utility function which works uniformly in all places. > > Differential Revision: https://reviews.llvm.org/D51152 > Reviewed By: fedor.sergeev llvm-svn: 340923
* [NFC] Unify guards detectionMax Kazantsev2018-08-291-2/+2
| | | | | | | | | | | We have multiple places in code where we try to identify whether or not some instruction is a guard. This patch factors out this logic into a separate utility function which works uniformly in all places. Differential Revision: https://reviews.llvm.org/D51152 Reviewed By: fedor.sergeev llvm-svn: 340921
* [ValueTracking] Fix assert message and add test case for r340546 and PR38677.Craig Topper2018-08-231-1/+1
| | | | | | The bug was already fixed. This just adds a test case for it. llvm-svn: 340556
* [ValueTracking] Fix an assert from r340480.Craig Topper2018-08-231-1/+3
| | | | | | | | | | We need to allow ConstantExpr Selects in addition to SelectInst. I'll try to put together a test case, but I wanted to fix the issues being reported. Fixes PR38677 llvm-svn: 340546
* [ValueTracking] Teach computeNumSignBits to understand min/max clamp ↵Craig Topper2018-08-221-1/+37
| | | | | | | | | | patterns with constant/splat values If we have a min/max pair we can do a better job of counting sign bits if we look at them together. This is similar to what is done in the SelectionDAG version of computeNumSignBits for ISD::SMAX/SMIN. Differential Revision: https://reviews.llvm.org/D51112 llvm-svn: 340480
* ValueTracking: Handle more instructions in isKnownNeverNaNMatt Arsenault2018-08-201-3/+33
| | | | llvm-svn: 340187
* [InstrSimplify,NewGVN] Add option to ignore additional instr info when ↵Florian Hahn2018-08-171-81/+94
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | simplifying. NewGVN uses InstructionSimplify for simplifications of leaders of congruence classes. It is not guaranteed that the metadata or other flags/keywords (like nsw or exact) of the leader is available for all members in a congruence class, so we cannot use it for simplification. This patch adds a InstrInfoQuery struct with a boolean field UseInstrInfo (which defaults to true to keep the current behavior as default) and a set of helper methods to get metadata/keywords for a given instruction, if UseInstrInfo is true. The whole thing might need a better name, to avoid confusion with TargetInstrInfo but I am not sure what a better name would be. The current patch threads through InstrInfoQuery to the required places, which is messier then it would need to be, if InstructionSimplify and ValueTracking would share the same Query struct. The reason I added it as a separate struct is that it can be shared between InstructionSimplify and ValueTracking's query objects. Also, some places do not need a full query object, just the InstrInfoQuery. It also updates some interfaces that do not take a Query object, but a set of optional parameters to take an additional boolean UseInstrInfo. See https://bugs.llvm.org/show_bug.cgi?id=37540. Reviewers: dberlin, davide, efriedma, sebpop, hiraditya Reviewed By: hiraditya Differential Revision: https://reviews.llvm.org/D47143 llvm-svn: 340031
* ValueTracking: Start enhancing isKnownNeverNaNMatt Arsenault2018-08-091-3/+21
| | | | llvm-svn: 339399
* ValueTracking: Handle canonicalize in CannotBeNegativeZeroMatt Arsenault2018-08-061-0/+1
| | | | | | | Also fix apparently missing test coverage for any of the handling here. llvm-svn: 339023
* Re-enable "[ValueTracking] Teach isKnownNonNullFromDominatingCondition about ↵Max Kazantsev2018-08-061-10/+33
| | | | | | | | | | | AND" The patch was reverted because of bug detected by sanitizer. The bug is fixed, respective tests added. Differential Revision: https://reviews.llvm.org/D50172 llvm-svn: 339005
* Revert rL338990 to see if it causes sanitizer failuresMax Kazantsev2018-08-061-28/+10
| | | | | | | | | Multiple failues reported by sanitizer-x86_64-linux, seem to be caused by this patch. Reverting to see if they sustain without it. Differential Revision: https://reviews.llvm.org/D50172 llvm-svn: 338994
* [ValueTracking] Teach isKnownNonNullFromDominatingCondition about ANDMax Kazantsev2018-08-061-10/+28
| | | | | | | | | | | `isKnownNonNullFromDominatingCondition` is able to prove non-null basing on `br` or `guard` by `%p != null` condition, but is unable to do so basing on `(%p != null) && %other_cond`. This patch allows it to do so. Differential Revision: https://reviews.llvm.org/D50172 Reviewed By: reames llvm-svn: 338990
* [ValueTracking] fix maxnum miscompile for cannotBeOrderedLessThanZero (PR37776)Sanjay Patel2018-08-021-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds the NAN checks suggested in PR37776: https://bugs.llvm.org/show_bug.cgi?id=37776 If both operands to maxnum are NAN, that should get constant folded, so we don't have to handle that case. This is the same assumption as other FP ops in this function. Returning 'false' is always conservatively correct. Copying from the bug report: Currently, we have this for "when is cannotBeOrderedLessThanZero (mustBePositiveOrNaN) true for maxnum": L ------------------- | Pos | Neg | NaN | ------------------------ |Pos | x | x | x | ------------------------ R |Neg | x | | x | ------------------------ |NaN | x | x | x | ------------------------ The cases with (Neg & NaN) are wrong. We should have: L ------------------- | Pos | Neg | NaN | ------------------------ |Pos | x | x | x | ------------------------ R |Neg | x | | | ------------------------ |NaN | x | | x | ------------------------ Differential Revision: https://reviews.llvm.org/D50081 llvm-svn: 338716
* Remove trailing spaceFangrui Song2018-07-301-6/+6
| | | | | | sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h} llvm-svn: 338293
* Fix llvm::ComputeNumSignBits with some operations and llvm.assumeStanislav Mekhanoshin2018-07-251-7/+7
| | | | | | | | | | Currently ComputeNumSignBits does early exit while processing some of the operations (add, sub, mul, and select). This prevents the function from using AssumptionCacheTracker if passed. Differential Revision: https://reviews.llvm.org/D49759 llvm-svn: 337936
* [InstrSimplify] fold sdiv if two operands are negated and non-overflowChen Zheng2018-07-211-8/+12
| | | | | | Differential Revision: https://reviews.llvm.org/D49382 llvm-svn: 337642
* [InstCombine] add more SPFofSPF foldingChen Zheng2018-07-161-24/+39
| | | | | | Differential Revision: https://reviews.llvm.org/D49238 llvm-svn: 337143
* [InstCombine] Simplify isKnownNegationFangrui Song2018-07-121-5/+2
| | | | llvm-svn: 336957
* [InstSimplify] simplify add instruction if two operands are negativeChen Zheng2018-07-121-0/+20
| | | | | | Differential Revision: https://reviews.llvm.org/D49216 llvm-svn: 336881
* llvm: Add support for "-fno-delete-null-pointer-checks"Manoj Gupta2018-07-091-1/+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
* Use Type::isIntOrPtrTy where possible, NFCVedant Kumar2018-07-061-1/+1
| | | | | | | | | | | It's a bit neater to write T.isIntOrPtrTy() over `T.isIntegerTy() || T.isPointerTy()`. I used Python's re.sub with this regex to update users: r'([\w.\->()]+)isIntegerTy\(\)\s*\|\|\s*\1isPointerTy\(\)' llvm-svn: 336462
* [ValueTracking] allow undef elements when matching vector absSanjay Patel2018-07-021-32/+27
| | | | llvm-svn: 336111
* Implement strip.invariant.groupPiotr Padlewski2018-07-021-9/+12
| | | | | | | | | | | | | | | | Summary: This patch introduce new intrinsic - strip.invariant.group that was described in the RFC: Devirtualization v2 Reviewers: rsmith, hfinkel, nlopes, sanjoy, amharc, kuhar Subscribers: arsenm, nhaehnle, JDevlieghere, hiraditya, xbolva00, llvm-commits Differential Revision: https://reviews.llvm.org/D47103 Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com> llvm-svn: 336073
* [ValueTracking] Match select abs pattern when there's an sext involvedJohn Brawn2018-06-041-6/+18
| | | | | | | | | | | | | | When checking a select to see if it matches an abs, allow the true/false values to be a sign-extension of the comparison value instead of requiring that they're directly the comparison value, as all the comparison cares about is the sign of the value. This fixes a regression due to r333702, where we were no longer generating ctlz due to isKnownNonNegative failing to match such a pattern. Differential Revision: https://reviews.llvm.org/D47631 llvm-svn: 333927
* [ValueTracking] Fix endless recursion in isKnownNonZero()Karl-Johan Karlsson2018-05-301-4/+5
| | | | | | | | | | | | | | | | | | | | | Summary: The isKnownNonZero() function have checks that abort the recursion when it reaches the specified max depth. However one of the recursive calls was placed before the max depth check was done, resulting in a endless recursion that eventually triggered a segmentation fault. Fixed the problem by moving the max depth check above the first recursive call. Reviewers: Prazek, nlopes, spatel, craig.topper, hfinkel Reviewed By: hfinkel Subscribers: hfinkel, bjope, llvm-commits Differential Revision: https://reviews.llvm.org/D47531 llvm-svn: 333557
* Recommit r333226 "[ValueTracking] Teach computeKnownBits that the result of ↵Craig Topper2018-05-251-0/+6
| | | | | | | | | | | | | | | | an absolute value pattern that uses nsw flag is always positive." Libfuzzer tests have been fixed to prevent being optimized. Original commit message: If the nsw flag is used in the absolute value then it is undefined for INT_MIN. For all other value it will produce a positive number. So we can assume the result is positive. This breaks some InstCombine abs/nabs combining tests because we simplify the second compare from known bits rather than as the whole pattern. Looks like we can probably fix it by adding a neg+abs/nabs combine to just swap the select operands. N Differential Revision: https://reviews.llvm.org/D47041 llvm-svn: 333300
* Revert r333226 "[ValueTracking] Teach computeKnownBits that the result of an ↵Craig Topper2018-05-251-6/+0
| | | | | | | | | | absolute value pattern that uses nsw flag is always positive." This breaks some libFuzzer tests. http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fuzzer/builds/15589/steps/check-fuzzer/logs/stdio Reverting to investigate llvm-svn: 333253
* [ValueTracking] Teach computeKnownBits that the result of an absolute value ↵Craig Topper2018-05-241-0/+6
| | | | | | | | | | | | pattern that uses nsw flag is always positive. If the nsw flag is used in the absolute value then it is undefined for INT_MIN. For all other value it will produce a positive number. So we can assume the result is positive. This breaks some InstCombine abs/nabs combining tests because we simplify the second compare from known bits rather than as the whole pattern. Looks like we can probably fix it by adding a neg+abs/nabs combine to just swap the select operands. Need to check alive to make sure there are no corner cases. Differential Revision: https://reviews.llvm.org/D47041 llvm-svn: 333226
* Fix aliasing of launder.invariant.groupPiotr Padlewski2018-05-231-5/+29
| | | | | | | | | | | | | | | | | | | Summary: Patch for capture tracking broke bootstrap of clang with -fstict-vtable-pointers which resulted in debbugging nightmare. It was fixed https://reviews.llvm.org/D46900 but as it turned out, there were other parts like inliner (computing of noalias metadata) that I found after bootstraping with enabled assertions. Reviewers: hfinkel, rsmith, chandlerc, amharc, kuhar Subscribers: JDevlieghere, eraman, llvm-commits, hiraditya Differential Revision: https://reviews.llvm.org/D47088 llvm-svn: 333070
* [InstCombine] Remove calloc transformationsDavid Bolvansky2018-05-221-29/+1
| | | | | | | | | | | | | | Summary: Previous patch does not care if a value is changed between calloc and strlen. This needs to be removed from InstCombine and maybe moved to DSE later after some rework. Reviewers: efriedma Reviewed By: efriedma Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D47218 llvm-svn: 333022
* [InstCombine] Calloc-ed strings optimizationsDavid Bolvansky2018-05-221-2/+31
| | | | | | | | | | | | | | | | Summary: Example cases: strlen(calloc(...)) -> 0 Reviewers: efriedma, bkramer Reviewed By: bkramer Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D47059 llvm-svn: 332990
* [EarlyCSE] Improve EarlyCSE of some absolute value cases.Craig Topper2018-05-211-0/+2
| | | | | | | | | | Change matchSelectPattern to return X and -X for ABS/NABS in a well defined order. Adjust EarlyCSE to account for this. Ensure the SPF result is some kind of min/max and not abs/nabs in one place in InstCombine that made me nervous. Prevously we returned the two operands of the compare part of the abs pattern. The RHS is always going to be a 0i, 1 or -1 constant. This isn't a very meaningful thing to return for any one. There's also some freedom in the abs pattern as to what happens when the value is equal to 0. This freedom led to early cse failing to match when different constants were used in otherwise equivalent operations. By returning the input and its negation in a defined order we can ensure an exact match. This also makes sure both patterns use the exact same subtract instruction for the negation. I believe CSE should evebntually make this happen and properly merge the nsw/nuw flags. But I'm not familiar with CSE and what order it does things in so it seemed like it might be good to really enforce that they were the same. Differential Revision: https://reviews.llvm.org/D47037 llvm-svn: 332865
* Propagate nonnull and dereferenceable throught launderPiotr Padlewski2018-05-181-1/+4
| | | | | | | | | | | | | | | Summary: invariant.group.launder should not stop propagation of nonnull and dereferenceable, because e.g. we would not be able to hoist loads speculatively. Reviewers: rsmith, amharc, kuhar, xbolva00, hfinkel Subscribers: hiraditya, llvm-commits Differential Revision: https://reviews.llvm.org/D46972 llvm-svn: 332788
* [InstCombine] Moving overflow computation logic from InstCombine to ↵Omer Paparo Bivas2018-05-101-0/+83
| | | | | | | | | ValueTracking; NFC Differential Revision: https://reviews.llvm.org/D46704 Change-Id: Ifabcbe431a2169743b3cc310f2a34fd706f13f02 llvm-svn: 332026
* [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.Shiva Chen2018-05-091-0/+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
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