| Issue |
125429
|
| Summary |
[maybe missed optimizaton] Suboptimal assembly with constexpr non-static VS static variable
|
| Labels |
new issue
|
| Assignees |
|
| Reporter |
chrooti
|
Looking at the following example on Godbolt: https://www.godbolt.org/z/cMoojqsd3
the assembly generated is optimal: to call writev one lea and three movs are emitted. If the static specifier is removed from the definition of `vecs` the assembly degenerates into a bunch of `movaps` that copy the `.data` section entries into the stack before passing a pointer to it.
Given that string literal are supposed to live in static storage and the the Iovecs are just pointers to them whether they are `static` or not probably should not make any difference to the generated asm output.
Notably in the IR output `@__const.main.vecs` switches from `internal` linkage in the optimal "static" case to `private unnamed_addr` in the "non-static" one, which seems both correct _and_ the eventual source of the possibly missed optimization.
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