Inserts an unreachable after an unconditional fail:
```
%0 = integer_literal 1
cond_fail %0, "message"
// following instructions
```
->
```
%0 = integer_literal 1
cond_fail %0, "message"
unreachable
deadblock:
// following instructions
```
Remove the old SILCombine implementation because it's not working well with OSSA lifetime completion.
This also required to move the `shouldRemoveCondFail` utility function from SILCombine to InstOptUtils.
This can cause several problems, e.g. false performance errors or even mis-compiles.
Instead, just ignore dead-end destroys as we don't want to "move" them away from `unreachable` instructions, anyway.
rdar://167553623
* remove borrow scopes which are borrowing an already guaranteed value
* allow optimizing lexical `begin_borrows` outside the mandatory pipeline
* fix: don't remove `begin_borrow [lexical]` of a `thin_to_thick_function` in the mandatory pipeline
When trying to remove a borrow scope by replacing all guaranteed uses with owned uses, don't bail for values which have debug_value uses.
Also make sure that the debug_value instructions are located within the owned value's lifetime.
Attempt to optimize by forwarding the destroy to operands of forwarding instructions.
```
%3 = struct $S (%1, %2)
destroy_value %3 // the only use of %3
```
->
```
destroy_value %1
destroy_value %2
```
The benefit of this transformation is that the forwarding instruction can be removed.
Also, handle `destroy_value` for phi arguments.
This is a more complex case where the destroyed value comes from different predecessors via a phi argument.
The optimization moves the `destroy_value` to each predecessor block.
```
bb1:
br bb3(%0)
bb2:
br bb3(%1)
bb3(%3 : @owned T):
... // no deinit-barriers
destroy_value %3 // the only use of %3
```
->
```
bb1:
destroy_value %0
br bb3
bb2:
destroy_value %1
br bb3
bb3:
...
```
This showed up on and off again on the source-compatibility testsuite project hummingbird.
The gist of the problem is that transformations may not rewrite the
type of an inlined instance of a variable without also createing a
deep copy of the inlined function with a different name (and e.g., a
specialization suffix). Otherwise the modified inlined variable will
cause an inconsistency when later compiler passes try to create the
abstract declaration of that inlined function as there would be
conflicting declarations for that variable.
Since SILDebugScope isn't yet available in the SwiftCompilerSources
this fix just drop these variables, but it would be absolutely
possible to preserve them by using the same mechanism that SILCloner
uses to create a deep copy of the inlined function scopes.
rdar://163167975
* remove `filterUsers(ofType:)`, because it's a duplication of `users(ofType:)`
* rename `filterUses(ofType:)` -> `filter(usersOfType:)`
* rename `ignoreUses(ofType:)` -> `ignore(usersOfType:)`
* rename `getSingleUser` -> `singleUser`
* implement `singleUse` with `Sequence.singleElement`
* implement `ignoreDebugUses` with `ignore(usersOfType:)`
This is a follow-up of eb1d5f484c.
This is done by splitting the `begin_borrow` of the whole struct into individual borrows of the fields (for trivial fields no borrow is needed).
And then sinking the `struct` to it's consuming use(s).
```
%3 = struct $S(%nonTrivialField, %trivialField) // owned
...
%4 = begin_borrow %3
%5 = struct_extract %4, #S.nonTrivialField
%6 = struct_extract %4, #S.trivialField
use %5, %6
end_borrow %4
...
end_of_lifetime %3
```
->
```
...
%5 = begin_borrow %nonTrivialField
use %5, %trivialField
end_borrow %5
...
%3 = struct $S(%nonTrivialField, %trivialField)
end_of_lifetime %3
```
This optimization is important for Array code where the Array buffer is constantly wrapped into structs and then extracted again to access the buffer.
ac619010e3 backfired when building the
stdlib on rebranch. This time the problem is reversed: we should be
interpreting an integer as unsigned where we no longer do, here:
8f7af45115/SwiftCompilerSources/Sources/Optimizer/InstructionSimplification/SimplifyLoad.swift (L78).
Rather than treating integers as signed by default, make
`Builder.createIntegerLiteral` accept a generic `FixedWidthInteger`, and
manipulate the value based on the generic type argument's signedness.
This doesn't entirely define away unintentional sign extensions, but
makes this mistake of humouring the parameter type less likely.
The assertion is hit through `TypeValueInst.simplify` when constructing
an integer literal instruction with a negative 64-bit `Swift.Int` and a
bit width of 32 (the target pointer bit width for arm64_32 watchOS).
This happens because we tell the `llvm::APInt` constructor to treat the
input integer as unsigned by default in `getAPInt`, and a negative
64-bit signed integer does not fit into 32 bits when interpreted as
unsigned.
Fix this by flipping the default signedness assumption for the Swift API
and introducing a convenience method for constructing a 1-bit integer
literal instruction, where the correct signedness assumption depends on
whether you want to use 1 or -1 for 'true'.
In the context of using an integer to construct an `llvm::APInt`, there
are 2 other cases where signedness matters that come to mind:
1. A non-decimal integer literal narrower than 64 bits, such as
`0xABCD`, is used.
2. The desired bit width is >64, since `llvm::APInt` can either
zero-extend or sign-extend the 64-bit integer it accepts.
Neither of these appear to be exercised in SwiftCompilerSources, and
if we ever do, the caller should be responsible for either (1)
appropriately extending the literal manually, e.g.
`Int(Int16(bitPattern: 0xABCD))`, or (2) passing along the appropriate
signedness.
The `explicit_copy_value` and `explicit_copy_addr` instructions are only used for non-copyable diagnostics in the mandatory pipeline.
After that we can replace them by their non-explicit counterparts so that optimizations (which only know of `copy_value` and `copy_addr`) can do their work.
rdar://159039552
When replacing an opened existential type with the concrete type, we didn't consider that the existential archetype can also be a "dependent" type of the root archetype.
For now, just bail in this case. In future we can support dependent archetypes as well.
Fixes a compiler crash.
rdar://158594365
We insert end_cow_mutation_addr for lifetime dependent values dependent on mutable addresses.
end_cow_mutation_addr can be simplified to end_cow_mutation after other optimizations like inlining, specialization etc
This PR adds an instruction simplification to transform end_cow_mutation_addr to end_cow_mutation.
This can enable array optimizations which look for end_cow_mutation.
Do not eliminate a mark_dependence on a begin_apply scope even though the token
has a trivial type.
Ideally, token would have a non-trivial Builtin type to avoid special cases.
This is a safer API than using
```
let argIdx = applySite.calleeArgumentIndex(of: op)
let arg = callee.arguments[argIdx]
```
because there is no potential misuse of the index.
We are going to need to add more flags to the various checked cast
instructions. Generalize the CastingIsolatedConformances bit in all of
these SIL instructions to an "options" struct that's easier to extend.
Precursor to rdar://152335805.
Optimize (the very inefficient) RawRepresentable comparison function call to a simple compare of enum tags.
For example,
```
enum E: String {
case a, b, c
}
```
is compared by getting the raw values of both operands and doing a string compare.
This peephole optimizations replaces the call to such a comparison function with a direct compare of the enum tags, which boils down to a single integer comparison instruction.
rdar://151788987
Reimplement the simplification in swift and add a new transformation:
```
%1 = unchecked_addr_cast %0 : $*Builtin.FixedArray<N, Element> to $*Element
```
->
```
%1 = vector_base_addr %0 : $*Builtin.FixedArray<N, Element>
```
If the block is passed to another function - either as closure argument or as closure capture - it's "converted" to a swift closure with the help of a thunk. The thunk just calls the block.
If this is done with a non-escaping partial_apply, the block does not escape.
rdar://149095630
