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path: root/src/backend/jit/llvm/llvmjit.c
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2019-02-01Renaming for new subscripting mechanismAlvaro Herrera
Over at patch https://commitfest.postgresql.org/21/1062/ Dmitry wants to introduce a more generic subscription mechanism, which allows subscripting not only arrays but also other object types such as JSONB. That functionality is introduced in a largish invasive patch, out of which this internal renaming patch was extracted. Author: Dmitry Dolgov Reviewed-by: Tom Lane, Arthur Zakirov Discussion: https://postgr.es/m/CA+q6zcUK4EqPAu7XRRO5CCjMwhz5zvg+rfWuLzVoxp_5sKS6=w@mail.gmail.com
2019-01-26Change function call information to be variable length.Andres Freund
Before this change FunctionCallInfoData, the struct arguments etc for V1 function calls are stored in, always had space for FUNC_MAX_ARGS/100 arguments, storing datums and their nullness in two arrays. For nearly every function call 100 arguments is far more than needed, therefore wasting memory. Arg and argnull being two separate arrays also guarantees that to access a single argument, two cachelines have to be touched. Change the layout so there's a single variable-length array with pairs of value / isnull. That drastically reduces memory consumption for most function calls (on x86-64 a two argument function now uses 64bytes, previously 936 bytes), and makes it very likely that argument value and its nullness are on the same cacheline. Arguments are stored in a new NullableDatum struct, which, due to padding, needs more memory per argument than before. But as usually far fewer arguments are stored, and individual arguments are cheaper to access, that's still a clear win. It's likely that there's other places where conversion to NullableDatum arrays would make sense, e.g. TupleTableSlots, but that's for another commit. Because the function call information is now variable-length allocations have to take the number of arguments into account. For heap allocations that can be done with SizeForFunctionCallInfoData(), for on-stack allocations there's a new LOCAL_FCINFO(name, nargs) macro that helps to allocate an appropriately sized and aligned variable. Some places with stack allocation function call information don't know the number of arguments at compile time, and currently variably sized stack allocations aren't allowed in postgres. Therefore allow for FUNC_MAX_ARGS space in these cases. They're not that common, so for now that seems acceptable. Because of the need to allocate FunctionCallInfo of the appropriate size, older extensions may need to update their code. To avoid subtle breakages, the FunctionCallInfoData struct has been renamed to FunctionCallInfoBaseData. Most code only references FunctionCallInfo, so that shouldn't cause much collateral damage. This change is also a prerequisite for more efficient expression JIT compilation (by allocating the function call information on the stack, allowing LLVM to optimize it away); previously the size of the call information caused problems inside LLVM's optimizer. Author: Andres Freund Reviewed-By: Tom Lane Discussion: https://postgr.es/m/20180605172952.x34m5uz6ju6enaem@alap3.anarazel.de
2019-01-14Make naming of tupdesc related structs more consistent with the rest of PG.Andres Freund
We usually don't change the name of structs between the struct name itself and the name of the typedef. Additionally, structs that are usually used via a typedef that hides being a pointer, are commonly suffixed Data. Change tupdesc code to follow those convention. This is triggered by a future patch that intends to forward declare TupleDescData in another header - keeping with the naming scheme makes that easier to understand. Author: Andres Freund Discussion: https://postgr.es/m/20190114000701.y4ttcb74jpskkcfb@alap3.anarazel.de
2019-01-02Update copyright for 2019Bruce Momjian
Backpatch-through: certain files through 9.4
2018-11-16Make TupleTableSlots extensible, finish split of existing slot type.Andres Freund
This commit completes the work prepared in 1a0586de36, splitting the old TupleTableSlot implementation (which could store buffer, heap, minimal and virtual slots) into four different slot types. As described in the aforementioned commit, this is done with the goal of making tuple table slots extensible, to allow for pluggable table access methods. To achieve runtime extensibility for TupleTableSlots, operations on slots that can differ between types of slots are performed using the TupleTableSlotOps struct provided at slot creation time. That includes information from the size of TupleTableSlot struct to be allocated, initialization, deforming etc. See the struct's definition for more detailed information about callbacks TupleTableSlotOps. I decided to rename TTSOpsBufferTuple to TTSOpsBufferHeapTuple and ExecCopySlotTuple to ExecCopySlotHeapTuple, as that seems more consistent with other naming introduced in recent patches. There's plenty optimization potential in the slot implementation, but according to benchmarking the state after this commit has similar performance characteristics to before this set of changes, which seems sufficient. There's a few changes in execReplication.c that currently need to poke through the slot abstraction, that'll be repaired once the pluggable storage patchset provides the necessary infrastructure. Author: Andres Freund and Ashutosh Bapat, with changes by Amit Khandekar Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de
2018-11-16Inline hot path of slot_getsomeattrs().Andres Freund
This yields a minor speedup, which roughly balances the loss from the upcoming introduction of callbacks to do some operations on slots. Author: Andres Freund Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de
2018-11-07Move EEOP_*_SYSVAR evaluation out of line.Andres Freund
This mainly de-duplicates code. As evaluating a system variable isn't the hottest path and the current inline implementation ends up calling out to an external function anyway, this is OK from a performance POV. The main motivation for de-duplicating is the upcoming slot abstraction work, after which there's not guaranteed to be a HeapTuple backing the slot. Author: Andres Freund, Amit Khandekar Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de
2018-11-02Fix spelling errors and typos in commentsMagnus Hagander
Author: Daniel Gustafsson <daniel@yesql.se>
2018-09-25Collect JIT instrumentation from workers.Andres Freund
Previously, when using parallel query, EXPLAIN (ANALYZE)'s JIT compilation timings did not include the overhead from doing so on the workers. Fix that. We do so by simply aggregating the cost of doing JIT compilation on workers and the leader together. Arguably that's not quite accurate, because the total time spend doing so is spent in parallel - but it's hard to do much better. For additional detail, when VERBOSE is specified, the stats for workers are displayed separately. Author: Amit Khandekar and Andres Freund Discussion: https://postgr.es/m/CAJ3gD9eLrz51RK_gTkod+71iDcjpB_N8eC6vU2AW-VicsAERpQ@mail.gmail.com Backpatch: 11-
2018-07-22LLVMJIT: Adapt to API changes in gdb and perf support.Andres Freund
During the work of upstreaming my previous patches for gdb and perf support the API changed. Adapt. Normally this wouldn't necessarily be something to backpatch, but the previous API wasn't upstream, and at least the gdb support is quite useful for debugging. Author: Andres Freund Backpatch: 11, where LLVM based JIT support was added.
2018-07-22LLVMJIT: Fix LLVM build for LLVM > 7.Andres Freund
The location of LLVMAddPromoteMemoryToRegisterPass moved. Author: Andres Freund Backpatch: 11, where LLVM based JIT support was added.
2018-06-26Remove duplicated return statement from llvmjit code.Andres Freund
The duplicated return clearly doesn't make sense / isn't reachable. Likely introduced by me (Andres), while revising the code. Author: Rushabh Lathia Discussion: https://postgr.es/m/CAGPqQf2raxWOcbuTP36M1rEF3=Rfo7oD29K3psdyHMeE5swBRg@mail.gmail.com
2018-03-28Add inlining support to LLVM JIT provider.Andres Freund
This provides infrastructure to allow JITed code to inline code implemented in C. This e.g. can be postgres internal functions or extension code. This already speeds up long running queries, by allowing the LLVM optimizer to optimize across function boundaries. The optimization potential currently doesn't reach its full potential because LLVM cannot optimize the FunctionCallInfoData argument fully away, because it's allocated on the heap rather than the stack. Fixing that is beyond what's realistic for v11. To be able to do that, use CLANG to convert C code to LLVM bitcode, and have LLVM build a summary for it. That bitcode can then be used to to inline functions at runtime. For that the bitcode needs to be installed. Postgres bitcode goes into $pkglibdir/bitcode/postgres, extensions go into equivalent directories. PGXS has been modified so that happens automatically if postgres has been compiled with LLVM support. Currently this isn't the fastest inline implementation, modules are reloaded from disk during inlining. That's to work around an apparent LLVM bug, triggering an apparently spurious error in LLVM assertion enabled builds. Once that is resolved we can remove the superfluous read from disk. Docs will follow in a later commit containing docs for the whole JIT feature. Author: Andres Freund Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de
2018-03-27Quick adaption of JIT tuple deforming to the fast default patch.Andres Freund
Instead using memset to set tts_isnull, call the new slot_getmissingattrs(). Also fix a bug (= instead of >=) in the code generation. Normally = is correct, but when repeatedly deforming fields not in a tuple (e.g. deform up to natts + 1 and then natts + 2) >= is needed. Discussion: https://postgr.es/m/20180328010053.i2qvsuuusst4lgmc@alap3.anarazel.de
2018-03-26Adapt to LLVM 7+ Orc API changes.Andres Freund
This is mostly done to be able to validate features and fixes submitted to LLVM. Given the size of these changes that seems acceptable. Author: Andres Freund
2018-03-26LLVMJIT: Free created module in LLVM < 5.Andres Freund
Due to the differing APIs between versions, I forgot to deallocate the generated module in older LLVM versions, leading to a memory leak. Author: Andres Freund
2018-03-26Correct some typos in the new JIT code.Andres Freund
Author: Thomas Munro
2018-03-26JIT tuple deforming in LLVM JIT provider.Andres Freund
Performing JIT compilation for deforming gains performance benefits over unJITed deforming from compile-time knowledge of the tuple descriptor. Fixed column widths, NOT NULLness, etc can be taken advantage of. Right now the JITed deforming is only used when deforming tuples as part of expression evaluation (and obviously only if the descriptor is known). It's likely to be beneficial in other cases, too. By default tuple deforming is JITed whenever an expression is JIT compiled. There's a separate boolean GUC controlling it, but that's expected to be primarily useful for development and benchmarking. Docs will follow in a later commit containing docs for the whole JIT feature. Author: Andres Freund Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de
2018-03-22Adapt expression JIT to stdbool.h introduction.Andres Freund
The LLVM JIT provider uses clang to synchronize types between normal C code and runtime generated code. Clang represents stdbool.h style booleans in return values & parameters differently from booleans stored in variables. Thus the expression compilation code from 2a0faed9d needs to be adapted to 9a95a77d9. Instead of hardcoding i8 as the type for booleans (which already was wrong on some edge case platforms!), use postgres' notion of a boolean as used for storage and for parameters. Per buildfarm animal xenodermus. Author: Andres Freund
2018-03-22Add expression compilation support to LLVM JIT provider.Andres Freund
In addition to the interpretation of expressions (which back evaluation of WHERE clauses, target list projection, aggregates transition values etc) support compiling expressions to native code, using the infrastructure added in earlier commits. To avoid duplicating a lot of code, only support emitting code for cases that are likely to be performance critical. For expression steps that aren't deemed that, use the existing interpreter. The generated code isn't great - some architectural changes are required to address that. But this already yields a significant speedup for some analytics queries, particularly with WHERE clauses filtering a lot, or computing multiple aggregates. Author: Andres Freund Tested-By: Thomas Munro Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de Disable JITing for VALUES() nodes. VALUES() nodes are only ever executed once. This is primarily helpful for debugging, when forcing JITing even for cheap queries. Author: Andres Freund Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de
2018-03-22Expand list of synchronized types and functions in LLVM JIT provider.Andres Freund
Author: Andres Freund Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de
2018-03-22Debugging and profiling support for LLVM JIT provider.Andres Freund
This currently requires patches to the LLVM codebase to be effective (submitted upstream), the GUCs are available without those patches however. Author: Andres Freund Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de
2018-03-22Support for optimizing and emitting code in LLVM JIT provider.Andres Freund
This commit introduces the ability to actually generate code using LLVM. In particular, this adds: - Ability to emit code both in heavily optimized and largely unoptimized fashion - Batching facility to allow functions to be defined in small increments, but optimized and emitted in executable form in larger batches (for performance and memory efficiency) - Type and function declaration synchronization between runtime generated code and normal postgres code. This is critical to be able to access struct fields etc. - Developer oriented jit_dump_bitcode GUC, for inspecting / debugging the generated code. - per JitContext statistics of number of functions, time spent generating code, optimizing, and emitting it. This will later be employed for EXPLAIN support. This commit doesn't yet contain any code actually generating functions. That'll follow in later commits. Documentation for GUCs added, and for JIT in general, will be added in later commits. Author: Andres Freund, with contributions by Pierre Ducroquet Testing-By: Thomas Munro, Peter Eisentraut Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de
2018-03-21Basic JIT provider and error handling infrastructure.Andres Freund
This commit introduces: 1) JIT provider abstraction, which allows JIT functionality to be implemented in separate shared libraries. That's desirable because it allows to install JIT support as a separate package, and because it allows experimentation with different forms of JITing. 2) JITContexts which can be, using functions introduced in follow up commits, used to emit JITed functions, and have them be cleaned up on error. 3) The outline of a LLVM JIT provider, which will be fleshed out in subsequent commits. Documentation for GUCs added, and for JIT in general, will be added in later commits. Author: Andres Freund, with architectural input from Jeff Davis Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de