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* Replace assert() with llvm_unreachable because it's obviously a typo.Rui Ueyama2018-10-121-1/+1
| | | | llvm-svn: 344395
* [codeview] Emit S_BUILDINFO and LF_BUILDINFO with cwd and source fileReid Kleckner2018-10-122-0/+50
| | | | | | | | | | | | Summary: We can fill in the command line and compiler path later if we want. Reviewers: zturner Subscribers: hiraditya, llvm-commits Differential Revision: https://reviews.llvm.org/D53179 llvm-svn: 344393
* [BPF] Use cstdint {,u}int*_t instead of linux/types.h __u32 __u16 ...Fangrui Song2018-10-122-9/+9
| | | | llvm-svn: 344387
* Disambiguate: s/make_unique/llvm::make_unique/. NFCEric Liu2018-10-121-13/+13
| | | | llvm-svn: 344385
* [BPF] Don't include linux/types.h and fix styleFangrui Song2018-10-123-153/+147
| | | | llvm-svn: 344381
* Better support for POSIX paths in PDBs.Zachary Turner2018-10-121-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This a resubmission of a patch which was previously reverted due to breaking several lld tests. The issues causing those failures have been fixed, so the patch is now resubmitted. ---Original Commit Message--- While it doesn't make a *ton* of sense for POSIX paths to be in PDBs, it's possible to occur in real scenarios involving cross compilation. The tools need to be able to handle this, because certain types of debugging scenarios are possible without a running process and so don't necessarily require you to be on a Windows system. These include post-mortem debugging and binary forensics (e.g. using a debugger to disassemble functions and examine symbols without running the process). There's changes in clang, LLD, and lldb in this patch. After this the cross-platform disassembly and source-list tests pass on Linux. Furthermore, the behavior of LLD can now be summarized by a much simpler rule than before: Unless you specify /pdbsourcepath and /pdbaltpath, the PDB ends up with paths that are valid within the context of the machine that the link is performed on. Differential Revision: https://reviews.llvm.org/D53149 llvm-svn: 344377
* [BPF] Some fixes after rL344366Fangrui Song2018-10-122-0/+3
| | | | | | | | | | * Move #include outside of namespaces * Add missing #include * Add out-of-line virtual destructor to BTFTypeEntry designated initializers should also be fixed llvm-svn: 344376
* [BPF] Add BTF generation for BPF targetYonghong Song2018-10-127-0/+662
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BTF is the debug format for BPF, a kernel virtual machine and widely used for tracing, networking and security, etc ([1]). Currently only instruction streams are passed to kernel, the kernel verifier verifies them before execution. In order to provide better visibility of bpf programs to user space tools, some debug information, e.g., function names and debug line information are desirable for kernel so tools can get such information with better annotation for jited instructions for performance or other reasons. The dwarf is too complicated in kernel and for BPF. Hence, BTF is designed to be the debug format for BPF ([2]). Right now, pahole supports BTF for types, which are generated based on dwarf sections in the ELF file. In order to annotate performance metrics for jited bpf insns, it is necessary to pass debug line info to the kernel. Furthermore, we want to pass the actual code to the kernel because of the following reasons: . bpf program typically is small so storage overhead should be small. . in bpf land, it is totally possible that an application loads the bpf program into the kernel and then that application quits, so holding debug info by the user space application is not practical. . having source codes directly kept by kernel would ease deployment since the original source code does not need ship on every hosts and kernel-devel package does not need to be deployed even if kernel headers are used. The only reliable time to get the source code is during compilation time. This will result in both more accurate information and easier deployment as stated in the above. Another consideration is for JIT. The project like bcc use MCJIT to compile a C program into bpf insns and load them to the kernel ([3]). The generated BTF sections will be readily available for such cases as well. This patch implemented generation of BTF info in llvm compiler. The BTF related sections will be generated when both -target bpf and -g are specified. Two sections are generated: .BTF contains all the type and string information, and .BTF.ext contains the func_info and line_info. The separation is related to how two sections are used differently in bpf loader, e.g., linux libbpf ([4]). The .BTF section can be loaded into the kernel directly while .BTF.ext needs loader manipulation before loading to the kernel. The format of the each section is roughly defined in llvm:include/llvm/MC/MCBTFContext.h and from the implementation in llvm:lib/MC/MCBTFContext.cpp. A later example also shows the contents in each section. The type and func_info are gathered during CodeGen/AsmPrinter by traversing dwarf debug_info. The line_info is gathered in MCObjectStreamer before writing to the object file. After all the information is gathered, the two sections are emitted in MCObjectStreamer::finishImpl. With cmake CMAKE_BUILD_TYPE=Debug, the compiler can dump out all the tables except insn offset, which will be resolved later as relocation records. The debug type "btf" is used for BTFContext dump. Dwarf tests the debug info generation with llvm-dwarfdump to decode the binary sections and check whether the result is expected. Currently we do not have such a tool yet. We will implement btf dump functionality in bpftool ([5]) as the bpftool is considered the recommended tool for bpf introspection. The implementation for type and func_info is tested with linux kernel test cases. The line_info is visually checked with dump from linux kernel libbpf ([4]) and checked with readelf dumping section raw data. Note that the .BTF and .BTF.ext information will not be emitted to assembly code and there is no assembler support for BTF either. In the below, with a clang/llvm built with CMAKE_BUILD_TYPE=Debug, Each table contents are shown for a simple C program. -bash-4.2$ cat -n test.c 1 struct A { 2 int a; 3 char b; 4 }; 5 6 int test(struct A *t) { 7 return t->a; 8 } -bash-4.2$ clang -O2 -target bpf -g -mllvm -debug-only=btf -c test.c Type Table: [1] FUNC name_off=1 info=0x0c000001 size/type=2 param_type=3 [2] INT name_off=12 info=0x01000000 size/type=4 desc=0x01000020 [3] PTR name_off=0 info=0x02000000 size/type=4 [4] STRUCT name_off=16 info=0x04000002 size/type=8 name_off=18 type=2 bit_offset=0 name_off=20 type=5 bit_offset=32 [5] INT name_off=22 info=0x01000000 size/type=1 desc=0x02000008 String Table: 0 : 1 : test 6 : .text 12 : int 16 : A 18 : a 20 : b 22 : char 27 : test.c 34 : int test(struct A *t) { 58 : return t->a; FuncInfo Table: sec_name_off=6 insn_offset=<Omitted> type_id=1 LineInfo Table: sec_name_off=6 insn_offset=<Omitted> file_name_off=27 line_off=34 line_num=6 column_num=0 insn_offset=<Omitted> file_name_off=27 line_off=58 line_num=7 column_num=3 -bash-4.2$ readelf -S test.o ...... [12] .BTF PROGBITS 0000000000000000 0000028d 00000000000000c1 0000000000000000 0 0 1 [13] .BTF.ext PROGBITS 0000000000000000 0000034e 0000000000000050 0000000000000000 0 0 1 [14] .rel.BTF.ext REL 0000000000000000 00000648 0000000000000030 0000000000000010 16 13 8 ...... -bash-4.2$ The latest linux kernel ([6]) can already support .BTF with type information. The [7] has the reference implementation in linux kernel side to support .BTF.ext func_info. The .BTF.ext line_info support is not implemented yet. If you have difficulty accessing [6], you can manually do the following to access the code: git clone https://github.com/yonghong-song/bpf-next-linux.git cd bpf-next-linux git checkout btf The change will push to linux kernel soon once this patch is landed. References: [1]. https://www.kernel.org/doc/Documentation/networking/filter.txt [2]. https://lwn.net/Articles/750695/ [3]. https://github.com/iovisor/bcc [4]. https://github.com/torvalds/linux/tree/master/tools/lib/bpf [5]. https://github.com/torvalds/linux/tree/master/tools/bpf/bpftool [6]. https://github.com/torvalds/linux [7]. https://github.com/yonghong-song/bpf-next-linux/tree/btf Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Differential Revision: https://reviews.llvm.org/D52950 llvm-svn: 344366
* [MC][ELF] fix newly added testNick Desaulniers2018-10-121-25/+25
| | | | | | | | | | | | | | | | | | | | | | | | | Summary: Reland of - r344197 "[MC][ELF] compute entity size for explicit sections" - r344206 "[MC][ELF] Fix section_mergeable_size.ll" after being reverted in r344278 due to build breakages from not specifying a target triple. Move test from test/CodeGen/Generic/ to test/MC/ELF/. Add explicit target triple so we don't try to run this test on non ELF targets. Reported: https://reviews.llvm.org/D53056#1261707 Reviewers: fhahn, rnk, espindola, NoQ Reviewed By: fhahn, rnk Subscribers: NoQ, MaskRay, rengolin, emaste, arichardson, llvm-commits, pirama, srhines Differential Revision: https://reviews.llvm.org/D53146 llvm-svn: 344360
* Pull out repeated value types. NFCI.Simon Pilgrim2018-10-121-6/+5
| | | | llvm-svn: 344355
* Pull out repeated value types. NFCI.Simon Pilgrim2018-10-121-3/+5
| | | | llvm-svn: 344354
* [SelectionDAG] Move VectorLegalizer::ExpandCTLZ codegen into ↵Simon Pilgrim2018-10-122-24/+5
| | | | | | | | SelectionDAGLegalize Generalize SelectionDAGLegalize's CTLZ expansion to handle vectors - lets VectorLegalizer::ExpandCTLZ to just pass the expansion on instead of repeating the same codegen. llvm-svn: 344349
* [DAGCombiner] rearrange extract_element+bitcast fold; NFCSanjay Patel2018-10-111-6/+8
| | | | | | | | | | I want to add another pattern here that includes scalar_to_vector, so this makes that patch smaller. I was hoping to remove the hasOneUse() check because it shouldn't be necessary for common codegen, but an AMDGPU test has a comment suggesting that the extra check makes things better on one of those targets. llvm-svn: 344320
* Revert "DwarfDebug: Pick next location in case of missing location at block ↵Matthias Braun2018-10-112-74/+41
| | | | | | | | | | | | | | | begin" It originally triggered a stepping problem in the debugger, which could be fixed by adjusting CodeGen/LexicalScopes.cpp however it seems we prefer the previous behavior anyway. See the discussion for details: http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20181008/593833.html This reverts commit r343880. This reverts commit r343874. llvm-svn: 344318
* [Pipeliner] Use the Index from Topo instead of relying on NodeNum. (NFC)Sumanth Gundapaneni2018-10-111-4/+14
| | | | | | | | | | In future, if we may add any new DAG mutations other than artificial dependencies, the NodeNum may not be valid. Instead the index from topological schedule DAG can be used as long as we update it with the DAG change. Differential Revision: https://reviews.llvm.org/D53104 llvm-svn: 344283
* [Pipeliner] Fix the Schedule DAG topoligical order.Sumanth Gundapaneni2018-10-111-0/+1
| | | | | | | | | This patch updates the DAG change to reflect in the topological ordering of the nodes. Differential Revision: https://reviews.llvm.org/D53105 llvm-svn: 344282
* Revert SymbolFileNativePDB plugin.Zachary Turner2018-10-111-4/+1
| | | | | | | | | This was originally causing some test failures on non-Windows platforms, which required fixes in the compiler and linker. After those fixes, however, other tests started failing. Reverting temporarily until I can address everything. llvm-svn: 344279
* Revert r344197 "[MC][ELF] compute entity size for explicit sections"Artem Dergachev2018-10-111-25/+25
| | | | | | | | | Revert r344206 "[MC][ELF] Fix section_mergeable_size.ll" They were causing failures on too many important buildbots for too long. Please revert eagerly if your fix takes more than a couple of hours to land! llvm-svn: 344278
* [DAG] Fix Big Endian in Load-Store forwardingNirav Dave2018-10-111-0/+5
| | | | | | | | | | | | | | Summary: Correct offset calculation in load-store forwarding for big-endian targets. Reviewers: rnk, RKSimon, waltl Subscribers: sdardis, nemanjai, hiraditya, jrtc27, atanasyan, jsji, llvm-commits Differential Revision: https://reviews.llvm.org/D53147 llvm-svn: 344272
* Better support for POSIX paths in PDBs.Zachary Turner2018-10-111-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | While it doesn't make a *ton* of sense for POSIX paths to be in PDBs, it's possible to occur in real scenarios involving cross compilation. The tools need to be able to handle this, because certain types of debugging scenarios are possible without a running process and so don't necessarily require you to be on a Windows system. These include post-mortem debugging and binary forensics (e.g. using a debugger to disassemble functions and examine symbols without running the process). There's changes in clang, LLD, and lldb in this patch. After this the cross-platform disassembly and source-list tests pass on Linux. Furthermore, the behavior of LLD can now be summarized by a much simpler rule than before: Unless you specify /pdbsourcepath and /pdbaltpath, the PDB ends up with paths that are valid within the context of the machine that the link is performed on. Differential Revision: https://reviews.llvm.org/D53149 llvm-svn: 344269
* [DAGCombiner] move comment closer to the corresponding code; NFC Sanjay Patel2018-10-111-2/+1
| | | | llvm-svn: 344255
* [MC][ELF] compute entity size for explicit sectionsNick Desaulniers2018-10-101-25/+25
| | | | | | | | | | | | | | | | | | | | Summary: Global variables might declare themselves to be in explicit sections. Calculate the entity size always to prevent assembler warnings "entity size for SHF_MERGE not specified" when sections are to be marked merge-able. Fixes PR31828. Reviewers: rnk, echristo Reviewed By: rnk Subscribers: llvm-commits, pirama, srhines Differential Revision: https://reviews.llvm.org/D53056 llvm-svn: 344197
* Replace most users of UnknownSize with LocationSize::unknown(); NFCGeorge Burgess IV2018-10-102-7/+7
| | | | | | | | | | | | Moving away from UnknownSize is part of the effort to migrate us to LocationSizes (e.g. the cleanup promised in D44748). This doesn't entirely remove all of the uses of UnknownSize; some uses require tweaks to assume that UnknownSize isn't just some kind of int. This patch is intended to just be a trivial replacement for all places where LocationSize::unknown() will Just Work. llvm-svn: 344186
* [DAGCombine] Improve Load-Store ForwardingNirav Dave2018-10-101-11/+134
| | | | | | | | | | | | | | | | | | Summary: Extend analysis forwarding loads from preceeding stores to work with extended loads and truncated stores to the same address so long as the load is fully subsumed by the store. Hexagon's swp-epilog-phis.ll and swp-memrefs-epilog1.ll test are deleted as they've no longer seem to be relevant. Reviewers: RKSimon, rnk, kparzysz, javed.absar Subscribers: sdardis, nemanjai, hiraditya, atanasyan, llvm-commits Differential Revision: https://reviews.llvm.org/D49200 llvm-svn: 344142
* [TargetLowering] SimplifyDemandedBits - rename demanded mask args. NFCI.Simon Pilgrim2018-10-101-80/+89
| | | | | | Help stop bugs like rL343935 by making the 'original' DemandedBits arg more obviously not the mask that is actually used. llvm-svn: 344138
* [TargetLowering] SimplifyDemandedBits - pull out repeated getOperands. NFCI.Simon Pilgrim2018-10-101-119/+119
| | | | | | Part of a minor cleanup to make all the switch statements more consistent prior to improving vector support. llvm-svn: 344136
* [TargetLowering] Add root node back to work list after successful ↵Simon Pilgrim2018-10-101-2/+6
| | | | | | | | | | SimplifyDemandedBits/SimplifyDemandedVectorElts Similar to what already happens in the DAGCombiner wrappers, this patch adds the root nodes back onto the worklist if the DCI wrappers' SimplifyDemandedBits/SimplifyDemandedVectorElts were successful. Differential Revision: https://reviews.llvm.org/D53026 llvm-svn: 344132
* [DAGCombiner] Expand combining of FP logical ops to sign-setting FP opsNemanja Ivanovic2018-10-091-3/+14
| | | | | | | | | | | | | | | | | We already do the following combines: (bitcast int (and (bitcast fp X to int), 0x7fff...) to fp) -> fabs X (bitcast int (xor (bitcast fp X to int), 0x8000...) to fp) -> fneg X When the target has "bit preserving fp logic". This patch just extends it to also combine: (bitcast int (or (bitcast fp X to int), 0x8000...) to fp) -> fneg (fabs X) As some targets have fnabs and even those that don't can efficiently lower both the fabs and the fneg. Differential revision: https://reviews.llvm.org/D44548 llvm-svn: 344093
* [SelectionDAG] Add SIGN_EXTEND_VECTOR_INREG and CONCAT_VECTORS support to ↵Simon Pilgrim2018-10-091-0/+30
| | | | | | | | SimplifyDemandedBits Fix for AVX1 masked load/store regression on D52964 llvm-svn: 344043
* ExpandPostRAPseudos: Fix alldefsAreDead() not removing operandsMatthias Braun2018-10-091-0/+2
| | | | | | | | One case left around nonsensical operands for the KILL instruction which the machine verifier checks for nowadays. While this should not hurt in release builds we should fix the machine verifier errors anyway. llvm-svn: 344008
* TwoAddressInstructionPass: Modernize/fix some comments; NFCMatthias Braun2018-10-081-5/+5
| | | | llvm-svn: 344006
* PHIElimination: Remove wrong comment; NFCMatthias Braun2018-10-081-2/+1
| | | | | | | | The comment was contradicting the code. Looking at history the feature was implemented a day after the comment was written without dropping the comment. llvm-svn: 344005
* MachineFunctionPrinterPass: Declare SlotIndexes as used if available; NFCMatthias Braun2018-10-081-0/+1
| | | | | | | This makes print-machineinstrs print the slot indexes in more situations. NFC for normal compilation. llvm-svn: 344004
* [DAGCombiner] simplify code for fmul with constant fold; NFCISanjay Patel2018-10-081-18/+8
| | | | llvm-svn: 343997
* [SelectionDAGBuilder][NFC] Pass LHSTy to getShiftAmountTy rather than RHSTyAlex Bradbury2018-10-081-1/+1
| | | | | | | | | | r126518 introduced a a type parameter to the getShiftAmountTy target hook. It produces the type of the shift (RHSTy), parameterised by the type of the value being shifted (LHSTy). SelectionDAGBuilder::visitShift passed RHSTy rather than LHSTy and this patch corrects this. The change is a no-op because in LLVM IR the LHS and RHS types for a shift must be equal anyway. llvm-svn: 343955
* Revert r343948 "[LegalizeDAG] Make one of the ReplaceNode signatures take an ↵Craig Topper2018-10-081-8/+6
| | | | | | | | ArrayRef instead a pointer to an array. Add assert on size of array. NFC" The assert is failing some asan tests on the bots. llvm-svn: 343950
* [LegalizeDAG] Make one of the ReplaceNode signatures take an ArrayRef ↵Craig Topper2018-10-081-6/+8
| | | | | | instead a pointer to an array. Add assert on size of array. NFC llvm-svn: 343948
* [LegalizeDAG] Move legalization of scatter and masked store from ↵Craig Topper2018-10-082-11/+10
| | | | | | | | | | LegalizeVectorOps to LegalizeDAG. This is where we legalize gather and masked load so this is consistent. Since these ops are always on vectors I've chosen to go with LegalizeDAG since that's what we do for other vector only ops like BUILD_VECTOR, VECTOR_SHUFFLE, etc. The ScalarizeMaskedMemIntrinsic pass should take care of scalarizing these before SelectionDAG so hopefully we don't need to worry about illegally typed scalar ops being emitted in the legalizing. If we did we would need to do this in LegalizeVectorOps so we could get the second type legalization that runs between LegalizeVectorOps and LegalizeDAG. llvm-svn: 343947
* [DAGCombiner] allow undef elts in vector fadd matchingSanjay Patel2018-10-071-1/+1
| | | | llvm-svn: 343945
* [DAGCombiner] allow undefs when matching vector splats for fmul foldsSanjay Patel2018-10-071-2/+2
| | | | llvm-svn: 343942
* [DAGCombiner] allow undef elts in vector fabs/fneg matchingSanjay Patel2018-10-071-1/+1
| | | | | | | | This change is proposed as a part of D44548, but we need this independently to avoid regressions from improved undef propagation in SimplifyDemandedVectorElts(). llvm-svn: 343940
* [DAGCombiner] shorten code for bitcast+fabs fold; NFCSanjay Patel2018-10-071-5/+2
| | | | llvm-svn: 343939
* [SelectionDAG] Respect multiple uses in SimplifyDemandedBits to ↵Simon Pilgrim2018-10-071-1/+1
| | | | | | | | | | | | SimplifyDemandedVectorElts simplification rL343913 was using SimplifyDemandedBits's original demanded mask instead of the adjusted 'NewMask' that accounts for multiple uses of the op (those variable names really need improving....). Annoyingly many of the test changes (back to pre-rL343913 state) are actually safe - but only because their multiple uses are all by PMULDQ/PMULUDQ. Thanks to Jan Vesely (@jvesely) for bisecting the bug. llvm-svn: 343935
* [LegalizeVectorOps] Make ExpandStrictFPOp return the result corresponding to ↵Craig Topper2018-10-071-1/+1
| | | | | | | | the result number of the SDValue passed in. It was always returning the chain which seems to be the result number of the SDValue in the lit tests we have. But I don't know if that's guaranteed. llvm-svn: 343933
* [SelectionDAG] Add SimplifyDemandedBits to SimplifyDemandedVectorElts ↵Simon Pilgrim2018-10-061-10/+46
| | | | | | | | | | | | | | | | simplification This patch enables SimplifyDemandedBits to call SimplifyDemandedVectorElts in cases where the demanded bits mask covers entire elements of a bitcasted source vector. There are a couple of cases here where simplification at a deeper level (such as through bitcasts) prevents further simplification - CommitTargetLoweringOpt only adds immediate uses/users back to the worklist when we might want to combine the original caller again to see what else it can simplify. As well as that I had to disable handling of bool vector until SimplifyDemandedVectorElts better supports some of their opcodes (SETCC, shifts etc.). Fixes PR39178 Differential Revision: https://reviews.llvm.org/D52935 llvm-svn: 343913
* [LiveDebugValues] Extend var ranges through artificial blocksVedant Kumar2018-10-051-12/+32
| | | | | | | | | | | | | | | | | | | | | | | | | ASan often introduces basic blocks consisting exclusively of instructions without debug locations, or with line 0 debug locations. LiveDebugValues needs to extend variable ranges through these artificial blocks. Otherwise, a lot of variables disappear -- even at -O0. Typically, LiveDebugValues does not extend a variable's range into a block unless the block is essentially "part of" the variable's scope (for a precise definition, see LexicalScopes::dominates). This patch relaxes the lexical dominance check for artificial blocks. This makes the following Swift program debuggable at -O0: ``` 1| var x = 100 2| print("x = \(x)") ``` rdar://39127144 Differential Revision: https://reviews.llvm.org/D52921 llvm-svn: 343890
* Clarify debug output in LiveDebugValuesVedant Kumar2018-10-051-7/+27
| | | | | | | MachineBasicBlocks often do not have names, so it helps to refer to them by block number when printing debug messages. llvm-svn: 343889
* [GlobalIsel] Add llvm.invariant.start and llvm.invariant.endJessica Paquette2018-10-051-0/+8
| | | | | | | | | | | | Port over the implementation in SelectionDAGBuilder.cpp into the IRTranslator and update the arm64-irtranslator test. These were causing fallbacks in CTMark/Bullet (-Rpass-missed=gisel-select), and this patch fixes that. https://reviews.llvm.org/D52945 llvm-svn: 343885
* [DebugInfo] Add support for DWARF5 call site-related attributesVedant Kumar2018-10-054-3/+110
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DWARF v5 introduces DW_AT_call_all_calls, a subprogram attribute which indicates that all calls (both regular and tail) within the subprogram have call site entries. The information within these call site entries can be used by a debugger to populate backtraces with synthetic tail call frames. Tail calling frames go missing in backtraces because the frame of the caller is reused by the callee. Call site entries allow a debugger to reconstruct a sequence of (tail) calls which led from one function to another. This improves backtrace quality. There are limitations: tail recursion isn't handled, variables within synthetic frames may not survive to be inspected, etc. This approach is not novel, see: https://gcc.gnu.org/wiki/summit2010?action=AttachFile&do=get&target=jelinek.pdf This patch adds an IR-level flag (DIFlagAllCallsDescribed) which lowers to DW_AT_call_all_calls. It adds the minimal amount of DWARF generation support needed to emit standards-compliant call site entries. For easier deployment, when the debugger tuning is LLDB, the DWARF requirement is adjusted to v4. Testing: Apart from check-{llvm, clang}, I built a stage2 RelWithDebInfo clang binary. Its dSYM passed verification and grew by 1.4% compared to the baseline. 151,879 call site entries were added. rdar://42001377 Differential Revision: https://reviews.llvm.org/D49887 llvm-svn: 343883
* DwarfDebug: Pick next location in case of missing location at block beginMatthias Braun2018-10-052-41/+74
| | | | | | | | | | | | | | | | | Context: Compiler generated instructions do not have a debug location assigned to them. However emitting 0-line records for all of them bloats the line tables for very little benefit so we usually avoid doing that. Not emitting anything will lead to the previous debug location getting applied to the locationless instructions. This is not desirable for block begin and after labels. Previously we would emit simply emit line-0 records in this case, this patch changes the behavior to do a forward search for a debug location in these cases before emitting a line-0 record to further reduce line table bloat. Inspired by the discussion in https://reviews.llvm.org/D52862 llvm-svn: 343874
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