The old analysis pass doesn't take into account profile data, nor does
it consider post-dominance. It primarily dealt with _fastPath/_slowPath.
A block that is dominated by a cold block is itself cold. That's true
whether it's forwards or backwards dominance.
We can also consider a call to any `Never` returning function as a
cold-exit, though the block(s) leading up to that call may be executed
frequently because of concurrency. For now, I'm ignoring the concurrency
case and assuming it's cold. To make use of this "no return" prediction,
use the `-enable-noreturn-prediction` flag, which is currently off by
default.
No update is needed for the values they produce. This pass should
really be refactored not to crash on instructions that aren't explicitly
listed or at least not to compile if not every instruction is listed.
rdar://133779160
In order for availability checks in iOS apps to be evaluated correctly when
running on macOS, the application binary must call a copy of
`_stdlib_isOSVersionAtLeast_AEIC()` that was emitted into the app, instead of
calling the `_stdlib_isOSVersionAtLeast()` function provided by the standard
library. This is because the call to the underlying compiler-rt function
`__isPlatformVersionAtLeast()` must be given the correct platform identifier
argument; if the call is not emitted into the client, then the macOS platform
identifier is used and the iOS version number will be mistakenly interpreted as
a macOS version number at runtime.
The `_stdlib_isOSVersionAtLeast()` function in the standard library is marked
`@_transparent` on iOS so that its call to `_stdlib_isOSVersionAtLeast_AEIC()`
is always inlined into the client. This works for the code generated by normal
`if #available` checks, but for the `@backDeployed` function thunks, the calls
to `_stdlib_isOSVersionAtLeast()` were not being inlined and that was causing
calls to `@backDeployed` functions to crash in iOS apps running on macOS since
their availability checks were being misevaluated.
The SIL optimizer has a heuristic which inhibits mandatory inlining in
functions that are classified as thunks, in order to save code size. This
heuristic needs to be relaxed in `@backDeployed` thunks, so that mandatory
inlining of `_stdlib_isOSVersionAtLeast()` can behave as expected. The change
should be safe since the only `@_transparent` function a `@backDeployed` thunk
is ever expected to call is `_stdlib_isOSVersionAtLeast()`.
Resolves rdar://134793410.
Also, move this rule from the computation of lowered captures in SIL,
to the computation of AST captures in Sema. This allows us to
correctly handle the case where an async function nests inside a
sync function. It also removes a special case that was added recently
to cope with a generic `self` type.
Fixes rdar://129366819.
Unknown uses of raw pointers should not result in bailing out when an
address is lexical--the destroy of the address will already not be
hoisted over any instructions which may access pointers. If the address
is not lexical however (such as any address when lexical lifetimes are
disabled), that rationale does not apply, so unknown uses of raw
pointers must cause hoisting to bail.
rdar://133969821
If there is no read from an indirect argument, this argument has to be dropped.
At the call site the store to the argument's memory location could have been removed (based on the callee's memory effects).
Therefore, converting such an unused indirect argument to a direct argument, would load an uninitialized value at the call site.
This would lead to verifier errors and in worst case to a miscompile because IRGen can implicitly use dead arguments, e.g. for getting the type of a class reference.
Instead of adding a "flag" (`m` in `...Tgm5`) make it more generic to allow to drop any unused argument.
Add all dropped arguments with a `t<n-1>` (where `<n-1>` is empty for n === 0). For example `...Ttt2g5`.
Just trying to improve logging to speed up triaging further. This is useful so
that I can quickly find specific closures we process by using the closure
numbering (e.x.: closure #1 in XXXX).
The reason why I am making this change is because I want to put a merge
operation on DiagnosticBehavior. This merge operation allows for
DiagnosticBehavior to work like a lattice. When one merges, one moves
potentially from fatal, error to things like note, ignore.
