The peephole causes the the formal access to the source and destination to
overlap. This results in unwanted exclusive access conflicts when assigning
from one struct stored property to another.
At John's suggestion I've added an isObviouslyNonConflicting() helper
method on LValue that tells when when it is safe to use the peephole
even when exclusivity enforcement enabled. For now, the helper is toothless. It
can be extended to claw back some of the peephole opportunities.
I am going to run it very early and use it to ensure that extra copies due to my
refactoring of SILGenPattern do not cause COW copies to be introduced.
For now, it does a very simple optimization, namely, it eliminates a copy_value,
with only a destroy_value user on a guaranteed parameter.
It is now disabled behind a flag.
- Add CompilerInvocation::getPCHHash
This will be used when creating a unique filename for a persistent
precompiled bridging header.
- Automatically generate and use a precompiled briding header
When we're given both -import-objc-header and -pch-output-dir
arguments, we will try to:
- Validate what we think the PCH filename should be for the bridging
header, based on the Swift PCH hash and the clang module hash.
- If we're successful, we'll just use it.
- If it's out of date or something else is wrong, we'll try to
emit it.
- This gives us a single filename which we can `stat` to check for the
validity of our code completion cache, which is keyed off of module
name, module filename, and module file age.
- Cache code completion results from imported modules
If we just have a single .PCH file imported, we can use that file as
part of the key used to cache declarations in a module. Because
multiple files can contribute to the __ObjC module, we've always given
it the phony filename "<imports>", which never exists, so `stat`-ing it
always fails and we never cache declarations in it.
This is extremely problematic for projects with huge bridging headers.
In the case where we have a single PCH import, this can bring warm code
completion times down to about 500ms from over 2-3s, so it can provide a
nice performance win for IDEs.
- Add a new test that performs two code-completion requests with a bridging header.
- Add some -pch-output-dir flags to existing SourceKit tests that import a bridging
header.
rdar://problem/31198982
Previously we would drop all serialized SIL from partial swiftmodule
files generated while compiling source in non-WMO mode; all that was
missing was linking it in.
This adds a frontend flag, and a test; driver change is coming up
next.
Progress on <rdar://problem/18913977>.
Add an -enforce-exclusivity=... flag to control enforcement of the law of
exclusivity. The flag takes one of four options:
"checked": Perform both static (compile-time) and dynamic (run-time) checks.
"unchecked": Perform only static enforcement. This is analogous to -Ounchecked.
"dynamic-only": Perform only dynamic checks. This is for staging purposes.
"none": Perform no checks at all. This is also for staging purposes.
The default, for now, is "none".
The intent is that in the fullness of time, "checked" and "unchecked" will
be the only legal options with "checked" the default. That is, static
enforcement will always be enabled and dynamic enforcement will be enabled
by default.
Adds the runtime implementation for copy-on-write existentials. This support is
enabled if SWIFT_RUNTIME_ENABLE_COW_EXISTENTIALS is defined. Focus is on
correctness -- not performance yet.
Don't use allocate/deallocate/projectBuffer witnesses for globals in cow
existential mode.
Use SWIFT_RUNTIME_ENABLE_COW_EXISTENTIALS configuration to set the default for
SILOptions.
This includes an IRGen fix to use the right projection in
emitMetatypeOfOpaqueExistential if SWIFT_RUNTIME_ENABLE_COW_EXISTENTIALS is set.
Use unknownRetain instead of native retain in dynamicCastToExistential.
This is preparation for a future patch adding experimental support to
treat Swift-level inout accesses as Thread Sanitizer writes. That patch will
extend the compiler so that additional TSan instrumentation is emitted
during SILGen, rather than solely during IRGen and at the LLVM level as occurs
now.
This patch adds a 'Sanitize' field to SILOptions and moves parsing of
'sanitize=...' to ParseSILArgs() from ParseIRGenArgs() where it is
now.
The sanitizer-coverage flag remains an IRGen-level option; SILGen does not
need to know about the coverage metric.
This is a hidden option. It should be used like: -assume-single-threaded
When this function is provided, the compiler assumes that the code will be executed in the single threaded mode. It then performs certain optimizations that can benefit from it, e.g. it marks as non-atomic all reference counting instructions in the user code being compiled.
This will allow for semantic arc work to remain behind a flag and not affect
other in tree developers. More importantly it enables for bots to be setup with
this flag enabled.
rdar://28685236
This change follows up on an idea from Michael (thanks!).
It enables debugging and profiling on SIL level, which is useful for compiler debugging.
There is a new frontend option -gsil which lets the compiler write a SIL file and generated debug info for it.
For details see docs/DebuggingTheCompiler.rst and the comments in SILDebugInfoGenerator.cpp.
* Replace 'Fast' with 'Unchecked' everywhere.
* Update the help text to specify DisableReplacement rather than
Replacement and to document Unchecked.
* Simplify tests slightly and add a tests for Unchecked.
This removes the -use-native-super-method flag and turns on dynamic
dispatch for native method invocations on super by default.
rdar://problem/22749732
Use the `super_method` instruction for non-final `func` and `class func`
declarations in native Swift classes. Previously, we would always emit
a static `function_ref` for these, which prevents resilient dynamic
dispatch.
This is hidden behind a -use-native-super-dispatch flag while I
survey the effects on devirtualization and stack promotion. When
that's figured out, I'll add more tests and update test cases that
still assume static dispatch.
rdar://problem/22749732
This patch implements the pre-specialization for the most popular generic types from the standard library. If there are invocations of generic functions from the standard library in the user-code and the compiler can find the specialized, optimized versions of these functions, then calls of generic functions are simply replaced by the calls of the specialized functions.
This feature is supposed to be used with -Onone to produce much faster (e.g. 5x-10x faster) executables in debug builds without impacting the compile time. In fact, the compile-time is even improved, because IRGen has less work to do. The feature can be considered a light-weight version of the -Odebug, because pre-specialization is limited in scope, but does not have a potentially negative compile-time impact compared to -Odebug. It is planned to enable it by default in the future.
This feature is disabled by default for the time being. It can be enabled by using a hidden flag: -Xllvm -use-prespecialized.
The implementation consists of two logical steps:
- When the standard library is being built, we force a creation of specializations for the most popular generic types from the stdlib, e.g. Arrays of integer and floating point types, Range<Int>, etc. The list of specializations is not fixed and can be easily altered by editing the Prespecialized.swift file, which is responsible for forcing the specialization of generic types (this is simple solution for now, until we have a proper annotation to indicate which specializations of a given generic type or function we want to generate by means of the pre-specialization). These specializations are then optimized and preserved in the stdlib dylib and in the Swift SIL module. The size increase of the stdlib due to creation of pre-specializations is currently about 3%-7%.
- When a user-code is being compiled with -Onone, the compiler would run a generic specializer over the user-code. If there are calls of generic functions from the standard library, the specializer would check if there is an existing specialization matching these invocations. If such a specialization is found, the original call is replaced by the call of this more efficient specialized version.
Swift SVN r30309
The value is set based on the -O command-line option. It is generally useful if SIL optimization passes can check the current optimization level.
A couple of subsequent commits are going to make use of this information.
Swift SVN r29653
I was always confused by the inconsistency of -sil-print-all and the other -sil-print options.
So I thought it would be a good idea to make -sil-print-all also an llvm option.
Together with some other internal options which are only used in the pass manager.
Swift SVN r29365
The only caveat is that:
1. We do not properly recognize when we have a let binding and we
perform a guaranteed dynamic call. In such a case, we add an extra
retain, release pair around the call. In order to get that case I will
need to refactor some code in Callee. I want to make this change, but
not at the expense of getting the rest of this work in.
2. Some of the protocol witness thunks generated have unnecessary
retains or releases in a similar manner.
But this is a good first step.
I am going to send a large follow up email with all of the relevant results, so
I can let the bots chew on this a little bit.
rdar://19933044
Swift SVN r27241
This adds the -profile-coverage-mapping option to swift, and teaches
SILGenProfiling to generate mappings from source ranges to counters.
Swift SVN r25266
This adds the -profile-generate flag, which enables LLVM's
instrumentation based profiling. It implements the instrumentation
for basic control flow, such as if statements, loops, and closures.
Swift SVN r25155
Main changes:
*) Instruction costs are not counted for blocks which are dead after inlining
*) Terminator instructions which get constant after inlining increase the threshold
*) Calls inside loops increase the threshold
In theory this should be a step towards making the performance not so dependent on the inlining heuristic.
But I must admit that I still did some fine tuning of all the parameters to get the best results.
Improvements in the benchmarks:
-O:
Chars: +11%
CommonMarkRender: +11%
DollarReduce: +22%
ForLoops: +22%
Forest: +10%
HeapSort: +36%
ImageProc: +14%
StrCat: +14%
StrComplexWalk: +70%
StrToInt: +11%
StringWalk: +99%
-Ounchecked:
Ary: +40%
Ary2: +30%
EditDistance: +22%
Forest: +18%
HeapSort: +50%
Histogram: +11%
StrCat: +12%
StrComplexWalk: +63%
StrSplitter: +11%
StrToInt: +17%
StringWalk: +75%
Regressions (I will file radars for them):
-Ounchecked:
PolymorphicCalls: -21%
QuickSort: -22%
Rectangles: -12%
Code size of the PerfTests_O decreased by 8%
Code size of the PerfTests_Ounchecked increased by 1%
Swift SVN r24801
If a subclass overrides methods with variance in the optionality of non-class-type members, emit a thunk to handle wrapping more optional parameters or results and force-unwrapping any IUO parameters made non-optional in the derived. For this to be useful, we need IRGen to finally pay attention to SILVTables, but this is a step on the way to fixing rdar://problem/19321484.
Swift SVN r24705
This flag enables one to specify a json file that expresses a specific
pipeline in the following format:
[
[
"$PASS_MANAGER_ID",
"run_n_times"|"run_to_fixed_point",
$NUM_ITERATIONS,
"$PASS1", "$PASS2", ...
],
...
]
This will make it easier to experiment with different pass pipelines by
allowing:
1. Automatic generation of pass pipelines without needing to recompile
the compiler itself.
2. Simple scripting of pass pipelines via the json meta language.
3. Enabling the easy expression and reproducability of a specific
pipeline ordering via radar.
In the next commit I will provide a python library for the generation of these
json files with a few types of pipeline generators already created.
Swift SVN r24055
This does not have any tests since I am going to start going through SILGen
tests and updating them for guaranteed self as the appropriate tests.
*NOTE* There is more work to be done in terms of thunks, but the basic
functionality is done.
rdar://15729033
Swift SVN r23653
This currently handles owned -> guaranteed argument conversion and dead argument
elimination.
RecursiveOwnedParameter||90.0%
ClassArrayGetter|||||||||23.3%
Life|||||||||||||||||||||16.7%
Prims||||||||||||||||||||11.2%
StringWalk|||||||||||||||5.7%
The next step is to implement SROA and address -> value optimizations.
rdar://16917049
Swift SVN r23023
