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* YJIT: Extract SHAPE_ID_NUM_BITS into a constant (#6863)Jemma Issroff2022-12-051-1/+1
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* Remove unused rb_shape_flag_shift and rb_shape_flag_maskJemma Issroff2022-12-021-2/+0
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* Extracted rb_shape_id_offsetJemma Issroff2022-12-021-0/+1
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* bail on compilation if the comptime receiver is frozenAaron Patterson2022-12-021-0/+1
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* implement IV writesAaron Patterson2022-12-021-0/+7
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* YJIT: Make case-when optimization respect === redefinition (#6846)Alan Wu2022-12-021-0/+4
| | | | | | | | | | | | | | | | | | * YJIT: Make case-when optimization respect === redefinition Even when a fixnum key is in the dispatch hash, if there is a case such that its basic operations for === is redefined, we need to fall back to checking each case like the interpreter. Semantically we're always checking each case by calling === in order, it's just that this is not observable when basic operations are intact. When all the keys are fixnums, though, we can do the optimization we're doing right now. Check for this condition. * Update yjit/src/cruby_bindings.inc.rs Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com> Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
* YJIT: Reorder branches for Fixnum opt_case_dispatch (#6841)Takashi Kokubun2022-12-011-0/+1
| | | | | | | | | | | * YJIT: Reorder branches for Fixnum opt_case_dispatch Co-authored-by: Maxime Chevalier-Boisvert <maxime.chevalierboisvert@shopify.com> Co-authored-by: Alan Wu <alansi.xingwu@shopify.com> * YJIT: Don't support too large values Co-authored-by: Maxime Chevalier-Boisvert <maxime.chevalierboisvert@shopify.com> Co-authored-by: Alan Wu <alansi.xingwu@shopify.com>
* 32 bit comparison on shape idAaron Patterson2022-11-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit changes the shape id comparisons to use a 32 bit comparison rather than 64 bit. That means we don't need to load the shape id to a register on x86 machines. Given the following program: ```ruby class Foo def initialize @foo = 1 @bar = 1 end def read [@foo, @bar] end end foo = Foo.new foo.read foo.read foo.read foo.read foo.read puts RubyVM::YJIT.disasm(Foo.instance_method(:read)) ``` The machine code we generated _before_ this change is like this: ``` == BLOCK 1/4, ISEQ RANGE [0,3), 65 bytes ====================== # getinstancevariable 0x559a18623023: mov rax, qword ptr [r13 + 0x18] # guard object is heap 0x559a18623027: test al, 7 0x559a1862302a: jne 0x559a1862502d 0x559a18623030: cmp rax, 4 0x559a18623034: jbe 0x559a1862502d # guard shape, embedded, and T_OBJECT 0x559a1862303a: mov rcx, qword ptr [rax] 0x559a1862303d: movabs r11, 0xffff00000000201f 0x559a18623047: and rcx, r11 0x559a1862304a: movabs r11, 0xb000000002001 0x559a18623054: cmp rcx, r11 0x559a18623057: jne 0x559a18625046 0x559a1862305d: mov rax, qword ptr [rax + 0x18] 0x559a18623061: mov qword ptr [rbx], rax == BLOCK 2/4, ISEQ RANGE [3,6), 0 bytes ======================= == BLOCK 3/4, ISEQ RANGE [3,6), 47 bytes ====================== # gen_direct_jmp: fallthrough # getinstancevariable # regenerate_branch # getinstancevariable # regenerate_branch 0x559a18623064: mov rax, qword ptr [r13 + 0x18] # guard shape, embedded, and T_OBJECT 0x559a18623068: mov rcx, qword ptr [rax] 0x559a1862306b: movabs r11, 0xffff00000000201f 0x559a18623075: and rcx, r11 0x559a18623078: movabs r11, 0xb000000002001 0x559a18623082: cmp rcx, r11 0x559a18623085: jne 0x559a18625099 0x559a1862308b: mov rax, qword ptr [rax + 0x20] 0x559a1862308f: mov qword ptr [rbx + 8], rax ``` After this change, it's like this: ``` == BLOCK 1/4, ISEQ RANGE [0,3), 41 bytes ====================== # getinstancevariable 0x5560c986d023: mov rax, qword ptr [r13 + 0x18] # guard object is heap 0x5560c986d027: test al, 7 0x5560c986d02a: jne 0x5560c986f02d 0x5560c986d030: cmp rax, 4 0x5560c986d034: jbe 0x5560c986f02d # guard shape 0x5560c986d03a: cmp word ptr [rax + 6], 0x19 0x5560c986d03f: jne 0x5560c986f046 0x5560c986d045: mov rax, qword ptr [rax + 0x10] 0x5560c986d049: mov qword ptr [rbx], rax == BLOCK 2/4, ISEQ RANGE [3,6), 0 bytes ======================= == BLOCK 3/4, ISEQ RANGE [3,6), 23 bytes ====================== # gen_direct_jmp: fallthrough # getinstancevariable # regenerate_branch # getinstancevariable # regenerate_branch 0x5560c986d04c: mov rax, qword ptr [r13 + 0x18] # guard shape 0x5560c986d050: cmp word ptr [rax + 6], 0x19 0x5560c986d055: jne 0x5560c986f099 0x5560c986d05b: mov rax, qword ptr [rax + 0x18] 0x5560c986d05f: mov qword ptr [rbx + 8], rax ``` The first ivar read is a bit more complex, but the second ivar read is much simpler. I think eventually we could teach the context about the shape, then emit only one shape guard.
* Remove USE_RVARGC codeAaron Patterson2022-11-141-3/+0
| | | | We don't need this constant to be exposed anymore, so remove it
* Implement optimize call (#6691)Jimmy Miller2022-11-081-1/+1
| | | This dispatches to a c func for doing the dynamic lookup. I experimented with chain on the proc but wasn't able to detect which call sites would be monomorphic vs polymorphic. There is definitely room for optimization here, but it does reduce exits.
* YJIT: Support invokeblock (#6640)Takashi Kokubun2022-11-021-1/+4
| | | | | | | | | * YJIT: Support invokeblock * Update yjit/src/backend/arm64/mod.rs * Update yjit/src/codegen.rs Co-authored-by: Maxime Chevalier-Boisvert <maximechevalierb@gmail.com>
* YJIT: Support nil and blockparamproxy as blockarg in send (#6492)Matthew Draper2022-10-261-0/+1
| | | | | Co-authored-by: John Hawthorn <john@hawthorn.email> Co-authored-by: John Hawthorn <john@hawthorn.email>
* YJIT: GC and recompile all code pages (#6406)Takashi Kokubun2022-10-251-0/+4
| | | | | when it fails to allocate a new page. Co-authored-by: Alan Wu <alansi.xingwu@shopify.com>
* YJIT: incorporate ruby_special_constsNobuyoshi Nakada2022-10-201-0/+3
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* YJIT doesn't need rb_obj_ensure_iv_index_mappingAaron Patterson2022-10-141-1/+0
| | | | We should make this function static and remove it from YJIT bindings.
* Implement optimize send in yjit (#6488)Jimmy Miller2022-10-111-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * Implement optimize send in yjit This successfully makes all our benchmarks exit way less for optimize send reasons. It makes some benchmarks faster, but not by as much as I'd like. I think this implementation works, but there are definitely more optimial arrangements. For example, what if we compiled send to a jump table? That seems like perhaps the most optimal we could do, but not obvious (to me) how to implement give our current setup. Co-authored-by: Alan Wu <XrXr@users.noreply.github.com> * Attempt at fixing the issues raised by @XrXr * fix allowlist * returns 0 instead of nil when not found * remove comment about encoding exception * Fix up c changes * Update assert Co-authored-by: Alan Wu <XrXr@users.noreply.github.com> * get rid of unneeded code and fix the flags * Apply suggestions from code review Co-authored-by: Alan Wu <XrXr@users.noreply.github.com> * rename and fix typo Co-authored-by: Alan Wu <XrXr@users.noreply.github.com>
* Revert "Revert "This commit implements the Object Shapes technique in CRuby.""Jemma Issroff2022-10-111-0/+7
| | | | This reverts commit 9a6803c90b817f70389cae10d60b50ad752da48f.
* YJIT: add support for calling bmethods (#6489)Alan Wu2022-10-041-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | * YJIT: fix a parameter name * YJIT: add support for calling bmethods This commit adds support for the VM_METHOD_TYPE_BMETHOD method type in YJIT. You can get these type of methods from facilities like Kernel#define_singleton_method and Module#define_method. Even though the body of these methods are blocks, the parameter setup for them is exactly the same as VM_METHOD_TYPE_ISEQ, so we can reuse the same logic in gen_send_iseq(). You can see this from how vm_call_bmethod() eventually calls setup_parameters_complex() with arg_setup_method. Bmethods do need their frame environment to be setup differently. We handle this by allowing callers of gen_send_iseq() to control the iseq, the frame flag, and the prev_ep. The `prev_ep` goes into the same location as the block handler would go into in an iseq method frame. Co-authored-by: John Hawthorn <john@hawthorn.email> Co-authored-by: John Hawthorn <john@hawthorn.email>
* Revert "This commit implements the Object Shapes technique in CRuby."Aaron Patterson2022-09-301-7/+0
| | | | This reverts commit 68bc9e2e97d12f80df0d113e284864e225f771c2.
* This commit implements the Object Shapes technique in CRuby.Jemma Issroff2022-09-281-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Object Shapes is used for accessing instance variables and representing the "frozenness" of objects. Object instances have a "shape" and the shape represents some attributes of the object (currently which instance variables are set and the "frozenness"). Shapes form a tree data structure, and when a new instance variable is set on an object, that object "transitions" to a new shape in the shape tree. Each shape has an ID that is used for caching. The shape structure is independent of class, so objects of different types can have the same shape. For example: ```ruby class Foo def initialize # Starts with shape id 0 @a = 1 # transitions to shape id 1 @b = 1 # transitions to shape id 2 end end class Bar def initialize # Starts with shape id 0 @a = 1 # transitions to shape id 1 @b = 1 # transitions to shape id 2 end end foo = Foo.new # `foo` has shape id 2 bar = Bar.new # `bar` has shape id 2 ``` Both `foo` and `bar` instances have the same shape because they both set instance variables of the same name in the same order. This technique can help to improve inline cache hits as well as generate more efficient machine code in JIT compilers. This commit also adds some methods for debugging shapes on objects. See `RubyVM::Shape` for more details. For more context on Object Shapes, see [Feature: #18776] Co-Authored-By: Aaron Patterson <tenderlove@ruby-lang.org> Co-Authored-By: Eileen M. Uchitelle <eileencodes@gmail.com> Co-Authored-By: John Hawthorn <john@hawthorn.email>
* Revert this until we can figure out WB issues or remove shapes from GCAaron Patterson2022-09-261-7/+0
| | | | | | | | | | Revert "* expand tabs. [ci skip]" This reverts commit 830b5b5c351c5c6efa5ad461ae4ec5085e5f0275. Revert "This commit implements the Object Shapes technique in CRuby." This reverts commit 9ddfd2ca004d1952be79cf1b84c52c79a55978f4.
* This commit implements the Object Shapes technique in CRuby.Jemma Issroff2022-09-261-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Object Shapes is used for accessing instance variables and representing the "frozenness" of objects. Object instances have a "shape" and the shape represents some attributes of the object (currently which instance variables are set and the "frozenness"). Shapes form a tree data structure, and when a new instance variable is set on an object, that object "transitions" to a new shape in the shape tree. Each shape has an ID that is used for caching. The shape structure is independent of class, so objects of different types can have the same shape. For example: ```ruby class Foo def initialize # Starts with shape id 0 @a = 1 # transitions to shape id 1 @b = 1 # transitions to shape id 2 end end class Bar def initialize # Starts with shape id 0 @a = 1 # transitions to shape id 1 @b = 1 # transitions to shape id 2 end end foo = Foo.new # `foo` has shape id 2 bar = Bar.new # `bar` has shape id 2 ``` Both `foo` and `bar` instances have the same shape because they both set instance variables of the same name in the same order. This technique can help to improve inline cache hits as well as generate more efficient machine code in JIT compilers. This commit also adds some methods for debugging shapes on objects. See `RubyVM::Shape` for more details. For more context on Object Shapes, see [Feature: #18776] Co-Authored-By: Aaron Patterson <tenderlove@ruby-lang.org> Co-Authored-By: Eileen M. Uchitelle <eileencodes@gmail.com> Co-Authored-By: John Hawthorn <john@hawthorn.email>
* Update bindgen crate (#6397)Takashi Kokubun2022-09-182-36/+49
| | | to get rid of deprecated indirect dependency, ansi_term
* YJIT: Implement specialized respond_to? (#6363)John Hawthorn2022-09-141-0/+2
| | | | | | | | | | | * Add rb_callable_method_entry_or_negative * YJIT: Implement specialized respond_to? This implements a specialized respond_to? in YJIT. * Update yjit/src/codegen.rs Co-authored-by: Maxime Chevalier-Boisvert <maximechevalierb@gmail.com>
* Initial support for VM_CALL_ARGS_SPLAT (#6341)Jimmy Miller2022-09-141-0/+1
| | | | | | | | | | | | | | | | | | | * Initial support for VM_CALL_ARGS_SPLAT This implements support for calls with splat (*) for some methods. In benchmarks this made very little difference for most benchmarks, but a large difference for binarytrees. Looking at side exits, many benchmarks now don't exit for splat, but exit for some other reason. Binarytrees however had a number of calls that used splat args that are now much faster. In my non-scientific benchmarking this made splat args performance on par with not using splat args at all. * Fix wording and whitespace Co-authored-by: Maxime Chevalier-Boisvert <maximechevalierb@gmail.com> * Get rid of side_effect reassignment Co-authored-by: Maxime Chevalier-Boisvert <maximechevalierb@gmail.com>
* Remove rb_iseq_eachJohn Hawthorn2022-09-011-1/+0
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* A64: Only clear icache when writing out new code ↵Alan Wu2022-08-291-0/+1
| | | | | | | | | | | | (https://github.com/Shopify/ruby/pull/442) Previously we cleared the cache for all the code in the system when we flip memory protection, which was prohibitively expensive since the operation is not constant time. Instead, only clear the cache for the memory region of newly written code when we write out new code. This brings the runtime for the 30k_if_else test down to about 6 seconds from the previous 45 seconds on my laptop.
* Use bindgen for old manual extern declarations ↵Alan Wu2022-08-291-0/+56
| | | | | | | | | | | (https://github.com/Shopify/ruby/pull/404) We have a large extern block in cruby.rs leftover from the port. We can use bindgen for it now and reserve the manual declaration for just a handful of vm_insnhelper.c functions. Fixup a few minor discrepencies bindgen found between the C declaration and the manual declaration. Mostly missing `const` on the C side.
* add --yjit-dump-iseqs param (https://github.com/Shopify/ruby/pull/332)Noah Gibbs2022-08-241-0/+7
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* Implement Objects on VWAPeter Zhu2022-07-151-1/+5
| | | | | | This commit implements Objects on Variable Width Allocation. This allows Objects with more ivars to be embedded (i.e. contents directly follow the object header) which improves performance through better cache locality.
* Switch YJIT to using rb_str_buf_append rather than rb_str_append when ↵Noah Gibbs (and/or Benchmark CI)2022-07-061-1/+1
| | | | encodings don't match, as discussed with byroot
* Add a check-yjit-bindgen-unused target. Add to CI. (#6066)Noah Gibbs2022-06-293-2/+6
| | | | | | | | | | | This fails if there are any unused rust-bindgen "allow" entries. For that target we turn on Rust warnings (there are a lot) and grep for the ones that correspond to unused allow entries. I've added check-yjit-bindgen-unused as a dependency of check-yjit-bindings, so unused allow entries will now fail CI. This change also removes our single unused allow entry (VM_CALL.*) which was known to be bad.
* YJIT: On-demand executable memory allocation; faster boot (#5944)Alan Wu2022-06-141-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit makes YJIT allocate memory for generated code gradually as needed. Previously, YJIT allocates all the memory it needs on boot in one go, leading to higher than necessary resident set size (RSS) and time spent on boot initializing the memory with a large memset(). Users should no longer need to search for a magic number to pass to `--yjit-exec-mem` since physical memory consumption should now more accurately reflect the requirement of the workload. YJIT now reserves a range of addresses on boot. This region start out with no access permission at all so buggy attempts to jump to the region crashes like before this change. To get this hardening at finer granularity than the page size, we fill each page with trapping instructions when we first allocate physical memory for the page. Most of the time applications don't need 256 MiB of executable code, so allocating on-demand ends up doing less total work than before. Case in point, a simple `ruby --yjit-call-threshold=1 -eitself` takes about half as long after this change. In terms of memory consumption, here is a table to give a rough summary of the impact: | Peak RSS in MiB | -eitself example | railsbench once | | :-------------: | ---------------: | --------------: | | before | 265 | 377 | | after | 11 | 143 | | no YJIT | 10 | 101 | A new module is introduced to handle allocation bookkeeping. `CodePtr` is moved into the module since it has a close relationship with the new `VirtualMemory` struct. This new interface has a slightly smaller surface than before in that marking a region as writable is no longer a public operation.
* Add ability to trace exit locations in yjit (#5970)Eileen M. Uchitelle2022-06-091-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When running with `--yjit-stats` turned on, yjit can inform the user what the most common exits are. While this is useful information it doesn't tell you the source location of the code that exited or what the code that exited looks like. This change intends to fix that. To use the feature, run yjit with the `--yjit-trace-exits` option, which will record the backtrace for every exit that occurs. This functionality requires the stats feature to be turned on. Calling `--yjit-trace-exits` will automatically set the `--yjit-stats` option. Users must call `RubyVM::YJIT.dump_exit_locations(filename)` which will Marshal dump the contents of `RubyVM::YJIT.exit_locations` into a file based on the passed filename. *Example usage:* Given the following script, we write to a file called `concat_array.dump` the results of `RubyVM::YJIT.exit_locations`. ```ruby def concat_array ["t", "r", *x = "u", "e"].join end 1000.times do concat_array end RubyVM::YJIT.dump_exit_locations("concat_array.dump") ``` When we run the file with this branch and the appropriate flags the stacktrace will be recorded. Note Stackprof needs to be installed or you need to point to the library directly. ``` ./ruby --yjit --yjit-call-threshold=1 --yjit-trace-exits -I/Users/eileencodes/open_source/stackprof/lib test.rb ``` We can then read the dump file with Stackprof: ``` ./ruby -I/Users/eileencodes/open_source/stackprof/lib/ /Users/eileencodes/open_source/stackprof/bin/stackprof --text concat_array.dump ``` Results will look similar to the following: ``` ================================== Mode: () Samples: 1817 (0.00% miss rate) GC: 0 (0.00%) ================================== TOTAL (pct) SAMPLES (pct) FRAME 1001 (55.1%) 1001 (55.1%) concatarray 335 (18.4%) 335 (18.4%) invokeblock 178 (9.8%) 178 (9.8%) send 140 (7.7%) 140 (7.7%) opt_getinlinecache ...etc... ``` Simply inspecting the `concatarray` method will give `SOURCE UNAVAILABLE` because the source is insns.def. ``` ./ruby -I/Users/eileencodes/open_source/stackprof/lib/ /Users/eileencodes/open_source/stackprof/bin/stackprof --text concat_array.dump --method concatarray ``` Result: ``` concatarray (nonexistent.def:1) samples: 1001 self (55.1%) / 1001 total (55.1%) callers: 1000 ( 99.9%) Object#concat_array 1 ( 0.1%) Gem.suffixes callees (0 total): code: SOURCE UNAVAILABLE ``` However if we go deeper to the callee we can see the exact source of the `concatarray` exit. ``` ./ruby -I/Users/eileencodes/open_source/stackprof/lib/ /Users/eileencodes/open_source/stackprof/bin/stackprof --text concat_array.dump --method Object#concat_array ``` ``` Object#concat_array (/Users/eileencodes/open_source/rust_ruby/test.rb:1) samples: 0 self (0.0%) / 1000 total (55.0%) callers: 1000 ( 100.0%) block in <main> callees (1000 total): 1000 ( 100.0%) concatarray code: | 1 | def concat_array 1000 (55.0%) | 2 | ["t", "r", *x = "u", "e"].join | 3 | end ``` The `--walk` option is recommended for this feature as it make it easier to traverse the tree of exits. *Goals of this feature:* This feature is meant to give more information when working on YJIT. The idea is that if we know what code is exiting we can decide what areas to prioritize when fixing exits. In some cases this means adding prioritizing avoiding certain exits in yjit. In more complex cases it might mean changing the Ruby code to be more performant when run with yjit. Ultimately the more information we have about what code is exiting AND why, the better we can make yjit. *Known limitations:* * Due to tracing exits, running this on large codebases like Rails can be quite slow. * On complex methods it can still be difficult to pinpoint the exact cause of an exit. * Stackprof is a requirement to to view the backtrace information from the dump file. Co-authored-by: Aaron Patterson <tenderlove@ruby-lang.org> Co-authored-by: Aaron Patterson <tenderlove@ruby-lang.org>
* Add special-case code for the String unary plus operator (#5982)Noah Gibbs2022-06-071-0/+1
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* Use bindgen to import Ruby constants wherever possible. (#5943)Noah Gibbs2022-06-061-0/+19
| | | | Constants that can't be imported via bindgen should have a comment saying why not.
* Use bindgen to import CRuby constants for YARV instruction bytecodesNoah Gibbs (and/or Benchmark CI)2022-05-261-0/+3
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* YJIT: Implement getblockparamAaron Patterson2022-05-121-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | This implements the getblockparam instruction. There are two cases we need to handle depending on whether or not VM_FRAME_FLAG_MODIFIED_BLOCK_PARAM is set in the environment flag. When the modified flag is unset, we need to call rb_vm_bh_to_procval to get a proc from our passed block, save the proc in the environment, and set the modified flag. In the case that the modified flag is set we are able to just use the existing proc in the environment. One quirk of this is that we need to call jit_prepare_routine_call early and ensure we update PC and SP regardless of the branch taken, so that we have a consistent SP offset at the start of the next instruction. We considered using a chain guard to generate these two paths separately, but decided against it because it's very common to see both and the modified case is basically a subset of the instructions in the unmodified case. This includes tests for both getblockparam and getblockparamproxy which was previously missing a test.
* Ruby shovel operator (<<) speedup. (#5896)Noah Gibbs2022-05-111-0/+7
| | | | | For string concat, see if compile-time encoding of strings matches. If so, use simple buffer string concat at runtime. Otherwise, use encoding-checking string concat.
* YJIT: Remove unnecessary `extern crate` declarationAlan Wu2022-04-271-1/+0
| | | | | | Thanks to suggestion from bjorn3 on GitHub. Co-authored-by: bjorn3 <bjorn3@users.noreply.github.com>
* Rust YJITAlan Wu2022-04-273-0/+640
In December 2021, we opened an [issue] to solicit feedback regarding the porting of the YJIT codebase from C99 to Rust. There were some reservations, but this project was given the go ahead by Ruby core developers and Matz. Since then, we have successfully completed the port of YJIT to Rust. The new Rust version of YJIT has reached parity with the C version, in that it passes all the CRuby tests, is able to run all of the YJIT benchmarks, and performs similarly to the C version (because it works the same way and largely generates the same machine code). We've even incorporated some design improvements, such as a more fine-grained constant invalidation mechanism which we expect will make a big difference in Ruby on Rails applications. Because we want to be careful, YJIT is guarded behind a configure option: ```shell ./configure --enable-yjit # Build YJIT in release mode ./configure --enable-yjit=dev # Build YJIT in dev/debug mode ``` By default, YJIT does not get compiled and cargo/rustc is not required. If YJIT is built in dev mode, then `cargo` is used to fetch development dependencies, but when building in release, `cargo` is not required, only `rustc`. At the moment YJIT requires Rust 1.60.0 or newer. The YJIT command-line options remain mostly unchanged, and more details about the build process are documented in `doc/yjit/yjit.md`. The CI tests have been updated and do not take any more resources than before. The development history of the Rust port is available at the following commit for interested parties: https://github.com/Shopify/ruby/commit/1fd9573d8b4b65219f1c2407f30a0a60e537f8be Our hope is that Rust YJIT will be compiled and included as a part of system packages and compiled binaries of the Ruby 3.2 release. We do not anticipate any major problems as Rust is well supported on every platform which YJIT supports, but to make sure that this process works smoothly, we would like to reach out to those who take care of building systems packages before the 3.2 release is shipped and resolve any issues that may come up. [issue]: https://bugs.ruby-lang.org/issues/18481 Co-authored-by: Maxime Chevalier-Boisvert <maximechevalierb@gmail.com> Co-authored-by: Noah Gibbs <the.codefolio.guy@gmail.com> Co-authored-by: Kevin Newton <kddnewton@gmail.com>