[llvm] [X86] Treat __ehdr_start as large (PR #79884)

[Arthur Eubanks via llvm-commits]

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@@ -57,6 +57,7 @@ target triple = "x86_64--linux"
 @opaque = external dso_local global %t
 @forced_small_data = dso_local global [10 x i32] zeroinitializer, code_model "small", align 16
 @forced_large_data = dso_local global [10 x i32] zeroinitializer, code_model "large", align 16
+ at __ehdr_start = external dso_local global i8
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aeubanks wrote:

it can be declared with hidden visibility, e.g. https://github.com/llvm/llvm-project/blob/e6fdbd17769d626c66e087b0fd9bbda0ea69194d/compiler-rt/lib/profile/InstrProfilingPlatformLinux.c#L159

if the declaration type has a size, we respect the size of the type in regards to the large data threshold since we assume the definition has the same type

we have a similar issue with __start/__stop symbols declarations, will send out a patch for that soon

https://github.com/llvm/llvm-project/pull/79884