Before this patch every Swift function would contain a top-level
DW_TAG_lexical_scope that didn't provide any useful information, used extra
space in the debug info and prevented local variables from showing up in virtual
async backtraces.
This is a follow-up to e9d557ae28. The
debug_value for the guard let binding is introduced by SGF.emitStmtCondition(),
so we also need to enter the debug scope before running that function.
rdar://74538257
* rename -sil-print-only-function to -sil-print-function and -sil-print-only-functions to -sil-print-functions
* to print single functions, don't require -Xllvm -sil-print-all. It's now sufficient to use e.g. -Xllvm -sil-print-function=<f>
But it's still possible to select functions with -sil-print-function(s) for other print options, -sil-print-after.
A GuardStmt can shadow bindings from outer scopes, so make sure
we actually create a new debug scope here.
Note that we push the scope, but pop it when the next innermost
debug scope ends. To keep track of this I added a new bit of state
to the debug scope stack, indicating that this scope originated
from a GuardStmt.
Ideally, debug info would rely on ASTScope which is the canonical
source of truth for this information. For now, this is a spot fix.
I filed <rdar://problem/72954242> to track implementing the longer
term solution.
Fixes <rdar://problem/72900354>.
I am doing this so I can start writing DI tests without this lowering occuring.
There never was a real reason for this code to be in DI beyond convenience. Now
it just makes writing tests more difficult. To prevent any test delta, I changed
all current DI tests to run this pass after DI.
