Type annotations for instruction operands are omitted, e.g.
```
%3 = struct $S(%1, %2)
```
Operand types are redundant anyway and were only used for sanity checking in the SIL parser.
But: operand types _are_ printed if the definition of the operand value was not printed yet.
This happens:
* if the block with the definition appears after the block where the operand's instruction is located
* if a block or instruction is printed in isolation, e.g. in a debugger
The old behavior can be restored with `-Xllvm -sil-print-types`.
This option is added to many existing test files which check for operand types in their check-lines.
Optimize code like:
puts("\(String.self)")
Optimizing string interpolation and optimizing C-strings are both done in StringOptimization.
A second run of the StringOptimization is needed in the pipeline to optimize such code, because the result of the interpolation-optimization must be cleaned up so that the C-String optimization can kick in.
Also, StringOptimization must handle struct_extract(struct(literal)), where the struct_extract may be in a called function.
To solve a phase ordering problem with inlining String semantics and inlining the `String(stringInterpolation: DefaultStringInterpolation)` constructor, we do a simple analysis of the callee. Doing this simple "interprocedural" analysis avoids relying on inlining that String constructor.
rdar://74941849
Replace a String initializer followed by String.utf8CString with a (UTF8 encoded) string literal.
This code pattern is generated when calling C functions with string literals, e.g.
puts("hello!")
rdar://74941849
