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* [BPF] turn on -mattr=+alu32 for cpu version v3 and laterYonghong Song2019-11-071-0/+1
| | | | | | | | | | | -mattr=+alu32 has shown good performance vs. without this attribute. Based on discussion at https://lore.kernel.org/bpf/1ec37838-966f-ec0b-5223-ca9b6eb0860d@fb.com/T/#t cpu version v3 should support -mattr=+alu32. This patch enabled alu32 if cpu version is v3, either specified by user or probed by the llvm. Differential Revision: https://reviews.llvm.org/D69957
* [BPF] add code-gen support for JMP32 instructionsJiong Wang2019-02-071-0/+6
| | | | | | | | | | | | | | | | | | | | | | | JMP32 instructions has been added to eBPF ISA. They are 32-bit variants of existing BPF conditional jump instructions, but the comparison happens on low 32-bit sub-register only, therefore some unnecessary extensions could be saved. JMP32 instructions will only be available for -mcpu=v3. Host probe hook has been updated accordingly. JMP32 instructions will only be enabled in code-gen when -mattr=+alu32 enabled, meaning compiling the program using sub-register mode. For JMP32 encoding, it is a new instruction class, and is using the reserved eBPF class number 0x6. This patch has been tested by compiling and running kernel bpf selftests with JMP32 enabled. Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> llvm-svn: 353384
* Update the file headers across all of the LLVM projects in the monorepoChandler Carruth2019-01-191-4/+3
| | | | | | | | | | | | | | | | | to reflect the new license. We understand that people may be surprised that we're moving the header entirely to discuss the new license. We checked this carefully with the Foundation's lawyer and we believe this is the correct approach. Essentially, all code in the project is now made available by the LLVM project under our new license, so you will see that the license headers include that license only. Some of our contributors have contributed code under our old license, and accordingly, we have retained a copy of our old license notice in the top-level files in each project and repository. llvm-svn: 351636
* bpf: introduce -mattr=dwarfris to disable DwarfUsesRelocationsAcrossSectionsYonghong Song2018-03-011-0/+1
| | | | | | | | | | | | | | | | | | | | | Commit e4507fb8c94b ("bpf: disable DwarfUsesRelocationsAcrossSections") disables MCAsmInfo DwarfUsesRelocationsAcrossSections unconditionally so that dwarf will not use cross section (between dwarf and symbol table) relocations. This new debug format enables pahole to dump structures correctly as libdwarves.so does not have BPF backend support yet. This new debug format, however, breaks bcc (https://github.com/iovisor/bcc) source debug output as llvm in-memory Dwarf support has some issues to handle it. More specifically, with DwarfUsesRelocationsAcrossSections disabled, JIT compiler does not generate .debug_abbrev and Dwarf DIE (debug info entry) processing is not happy about this. This patch introduces a new flag -mattr=dwarfris (dwarf relocation in section) to disable DwarfUsesRelocationsAcrossSections. DwarfUsesRelocationsAcrossSections is true by default. Signed-off-by: Yonghong Song <yhs@fb.com> llvm-svn: 326505
* bpf: New target attribute "alu32" for 32-bit subregister supportYonghong Song2018-02-231-0/+2
| | | | | | | | | | | | | | | | | | This new attribute aims to control the enablement of 32-bit subregister support on eBPF backend. Name the interface as "alu32" is because we in particular want to enable the generation of BPF_ALU32 instructions by enable subregister support. This attribute could be used in the following format with llc: llc -mtriple=bpf -mattr=[+|-]alu32 It is disabled at default. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Yonghong Song <yhs@fb.com> llvm-svn: 325982
* bpf: add variants of -mcpu=# and support for additional jmp insnsYonghong Song2017-08-231-1/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | -mcpu=# will support: . generic: the default insn set . v1: insn set version 1, the same as generic . v2: insn set version 2, version 1 + additional jmp insns . probe: the compiler will probe the underlying kernel to decide proper version of insn set. We did not not use -mcpu=native since llc/llvm will interpret -mcpu=native as the underlying hardware architecture regardless of -march value. Currently, only x86_64 supports -mcpu=probe. Other architecture will silently revert to "generic". Also added -mcpu=help to print available cpu parameters. llvm will print out the information only if there are at least one cpu and at least one feature. Add an unused dummy feature to enable the printout. Examples for usage: $ llc -march=bpf -mcpu=v1 -filetype=asm t.ll $ llc -march=bpf -mcpu=v2 -filetype=asm t.ll $ llc -march=bpf -mcpu=generic -filetype=asm t.ll $ llc -march=bpf -mcpu=probe -filetype=asm t.ll $ llc -march=bpf -mcpu=v3 -filetype=asm t.ll 'v3' is not a recognized processor for this target (ignoring processor) ... $ llc -march=bpf -mcpu=help -filetype=asm t.ll Available CPUs for this target: generic - Select the generic processor. probe - Select the probe processor. v1 - Select the v1 processor. v2 - Select the v2 processor. Available features for this target: dummy - unused feature. Use +feature to enable a feature, or -feature to disable it. For example, llc -mcpu=mycpu -mattr=+feature1,-feature2 ... Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> llvm-svn: 311522
* Revert r247692: Replace Triple with a new TargetTuple in MCTargetDesc/* and ↵Daniel Sanders2015-09-151-2/+2
| | | | | | | | related. NFC. Eric has replied and has demanded the patch be reverted. llvm-svn: 247702
* Re-commit r247683: Replace Triple with a new TargetTuple in MCTargetDesc/* ↵Daniel Sanders2015-09-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | and related. NFC. Summary: This is the first patch in the series to migrate Triple's (which are ambiguous) to TargetTuple's (which aren't). For the moment, TargetTuple simply passes all requests to the Triple object it holds. Once it has replaced Triple, it will start to implement the interface in a more suitable way. This change makes some changes to the public C++ API. In particular, InitMCSubtargetInfo(), createMCRelocationInfo(), and createMCSymbolizer() now take TargetTuples instead of Triples. The other public C++ API's have been left as-is for the moment to reduce patch size. This commit also contains a trivial patch to clang to account for the C++ API change. Thanks go to Pavel Labath for fixing LLDB for me. Reviewers: rengolin Subscribers: jyknight, dschuff, arsenm, rampitec, danalbert, srhines, javed.absar, dsanders, echristo, emaste, jholewinski, tberghammer, ted, jfb, llvm-commits, rengolin Differential Revision: http://reviews.llvm.org/D10969 llvm-svn: 247692
* Revert r247684 - Replace Triple with a new TargetTuple ...Daniel Sanders2015-09-151-2/+2
| | | | | | LLDB needs to be updated in the same commit. llvm-svn: 247686
* Replace Triple with a new TargetTuple in MCTargetDesc/* and related. NFC.Daniel Sanders2015-09-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This is the first patch in the series to migrate Triple's (which are ambiguous) to TargetTuple's (which aren't). For the moment, TargetTuple simply passes all requests to the Triple object it holds. Once it has replaced Triple, it will start to implement the interface in a more suitable way. This change makes some changes to the public C++ API. In particular, InitMCSubtargetInfo(), createMCRelocationInfo(), and createMCSymbolizer() now take TargetTuples instead of Triples. The other public C++ API's have been left as-is for the moment to reduce patch size. This commit also contains a trivial patch to clang to account for the C++ API change. Reviewers: rengolin Subscribers: jyknight, dschuff, arsenm, rampitec, danalbert, srhines, javed.absar, dsanders, echristo, emaste, jholewinski, tberghammer, ted, jfb, llvm-commits, rengolin Differential Revision: http://reviews.llvm.org/D10969 llvm-svn: 247683
* Remove getDataLayout() from TargetSelectionDAGInfo (had no users)Mehdi Amini2015-07-091-1/+1
| | | | | | | | | | | | | | | | | | Summary: Remove empty subclass in the process. This change is part of a series of commits dedicated to have a single DataLayout during compilation by using always the one owned by the module. Reviewers: echristo Subscribers: jholewinski, llvm-commits, rafael, yaron.keren, ted Differential Revision: http://reviews.llvm.org/D11045 From: Mehdi Amini <mehdi.amini@apple.com> llvm-svn: 241780
* Replace string GNU Triples with llvm::Triple in MCSubtargetInfo and ↵Daniel Sanders2015-06-101-1/+1
| | | | | | | | | | | | | | | | | | create*MCSubtargetInfo(). NFC. Summary: This continues the patch series to eliminate StringRef forms of GNU triples from the internals of LLVM that began in r239036. Reviewers: rafael Reviewed By: rafael Subscribers: rafael, ted, jfb, llvm-commits, rengolin, jholewinski Differential Revision: http://reviews.llvm.org/D10311 llvm-svn: 239467
* Remove an argument-less call to getSubtargetImpl from TargetLoweringBase.Eric Christopher2015-02-261-1/+1
| | | | | | | | | This required plumbing a TargetRegisterInfo through computeRegisterProperties and into findRepresentativeClass which uses it for register class iteration. This required passing a subtarget into a few target specific initializations of TargetLowering. llvm-svn: 230583
* bpf: fix build due to 'Move DataLayout back to the TargetMachine'Alexei Starovoitov2015-01-261-2/+2
| | | | | | commit r227113 moved DataLayout llvm-svn: 227133
* BPF backendAlexei Starovoitov2015-01-241-0/+31
Summary: V8->V9: - cleanup tests V7->V8: - addressed feedback from David: - switched to range-based 'for' loops - fixed formatting of tests V6->V7: - rebased and adjusted AsmPrinter args - CamelCased .td, fixed formatting, cleaned up names, removed unused patterns - diffstat: 3 files changed, 203 insertions(+), 227 deletions(-) V5->V6: - addressed feedback from Chandler: - reinstated full verbose standard banner in all files - fixed variables that were not in CamelCase - fixed names of #ifdef in header files - removed redundant braces in if/else chains with single statements - fixed comments - removed trailing empty line - dropped debug annotations from tests - diffstat of these changes: 46 files changed, 456 insertions(+), 469 deletions(-) V4->V5: - fix setLoadExtAction() interface - clang-formated all where it made sense V3->V4: - added CODE_OWNERS entry for BPF backend V2->V3: - fix metadata in tests V1->V2: - addressed feedback from Tom and Matt - removed top level change to configure (now everything via 'experimental-backend') - reworked error reporting via DiagnosticInfo (similar to R600) - added few more tests - added cmake build - added Triple::bpf - tested on linux and darwin V1 cover letter: --------------------- recently linux gained "universal in-kernel virtual machine" which is called eBPF or extended BPF. The name comes from "Berkeley Packet Filter", since new instruction set is based on it. This patch adds a new backend that emits extended BPF instruction set. The concept and development are covered by the following articles: http://lwn.net/Articles/599755/ http://lwn.net/Articles/575531/ http://lwn.net/Articles/603983/ http://lwn.net/Articles/606089/ http://lwn.net/Articles/612878/ One of use cases: dtrace/systemtap alternative. bpf syscall manpage: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b4fc1a460f3017e958e6a8ea560ea0afd91bf6fe instruction set description and differences vs classic BPF: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/networking/filter.txt Short summary of instruction set: - 64-bit registers R0 - return value from in-kernel function, and exit value for BPF program R1 - R5 - arguments from BPF program to in-kernel function R6 - R9 - callee saved registers that in-kernel function will preserve R10 - read-only frame pointer to access stack - two-operand instructions like +, -, *, mov, load/store - implicit prologue/epilogue (invisible stack pointer) - no floating point, no simd Short history of extended BPF in kernel: interpreter in 3.15, x64 JIT in 3.16, arm64 JIT, verifier, bpf syscall in 3.18, more to come in the future. It's a very small and simple backend. There is no support for global variables, arbitrary function calls, floating point, varargs, exceptions, indirect jumps, arbitrary pointer arithmetic, alloca, etc. From C front-end point of view it's very restricted. It's done on purpose, since kernel rejects all programs that it cannot prove safe. It rejects programs with loops and with memory accesses via arbitrary pointers. When kernel accepts the program it is guaranteed that program will terminate and will not crash the kernel. This patch implements all 'must have' bits. There are several things on TODO list, so this is not the end of development. Most of the code is a boiler plate code, copy-pasted from other backends. Only odd things are lack or < and <= instructions, specialized load_byte intrinsics and 'compare and goto' as single instruction. Current instruction set is fixed, but more instructions can be added in the future. Signed-off-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Subscribers: majnemer, chandlerc, echristo, joerg, pete, rengolin, kristof.beyls, arsenm, t.p.northover, tstellarAMD, aemerson, llvm-commits Differential Revision: http://reviews.llvm.org/D6494 llvm-svn: 227008
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