[SR-2089] SIL verifier failures with static inline stubs #44697
Description
| Previous ID | SR-2089 |
| Radar | rdar://problem/27378253 |
| Original Reporter | @stephentyrone |
| Type | Bug |
| Status | Closed |
| Resolution | Done |
Additional Detail from JIRA
| Votes | 0 |
| Component/s | |
| Labels | Bug |
| Assignee | @eeckstein |
| Priority | Medium |
md5: 8ff06a40a5b30dcb934f2e9ce141354f
Issue Description:
In order to expose an efficient square root implementation in the stdlib, I tried making the libc shims static inline in (#3454
~~~
static inline float _swift_stdlib_sqrtf(float x) { return __builtin_sqrt❌; }
~~~
This "works" and we get the codegen we want, but under certain conditions we get SIL verifier failures. I'm not sure whether this is a compiler bug or a verifier bug. There are not extant `static inline` stubs from what I can tell, so it's not surprising this hasn't come up before, but we want to handle sqrt this way to avoid an extra layer of indirection; function call overhead is quite substantial for a single-instruction operation, and we can't use `@llvm.sqrt` because it has the wrong semantics.