[SR-14814] Incorrect parsing on 'forwarding' directive in SIL #57162
Description
| Previous ID | SR-14814 |
| Radar | None |
| Original Reporter | myhsu (JIRA User) |
| Type | Bug |
| Status | Resolved |
| Resolution | Done |
Environment
Swift HEAD: 544c796
Arch: x86_64
OS: Mac OSX 11.4
Xcode version: 12.5.1
Additional Detail from JIRA
| Votes | 0 |
| Component/s | Compiler |
| Labels | Bug |
| Assignee | myhsu (JIRA) |
| Priority | Medium |
md5: 1b0272376fcf532d415620f8b212588a
Issue Description:
With this input code:
struct Point {
var x: Int
var y: Int
}
func foo(p: Point) -> Int {
p.x + p.y
}If we try to attach debug info onto its corresponding SIL code using the following command:
swiftc -emit-sil -Xllvm -sil-print-debuginfo simple.swift -o simple.silAnd try to parse the generated SIL code with `sil-opt`:
sil-opt -O simple.silIt will give us the following error:
./simple.sil:21:45: error: expected 'forwarding' in SIL instruction
%3 = struct $Int32 (%2 : $Builtin.Int32), scope 1 // user: %4
^
...
./simple.sil:66:18: error: expected 'forwarding' in SIL instruction
%6 = tuple (), loc "simple.swift":2:9, scope 4 // user: %7
^
./simple.sil:81:46: error: expected 'forwarding' in SIL instruction
%2 = struct_extract %0 : $Point, #Point.y, scope 5 // user: %3
^
...
Take `struct_extract` instruction as an example: The SIL parser always expects a "forwarding" identifier if there is a comma follows after the operands. However, in this case we have debug info directive follows after the comma – which is totally legit – so the parser bails out.