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JIT: Ensure correct alignment of CILJit singleton #73451

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Merged
jkotas merged 1 commit into from
Aug 5, 2022
+2 −13
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JIT: Ensure correct alignment of CILJit singleton #73451

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15 changes: 2 additions & 13 deletions src/coreclr/jit/ee_il_dll.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -152,18 +152,6 @@ void jitShutdown(bool processIsTerminating)

/*****************************************************************************/

struct CILJitSingletonAllocator
{
int x;
};
const CILJitSingletonAllocator CILJitSingleton = {0};

void* __cdecl operator new(size_t, const CILJitSingletonAllocator&)
{
static char CILJitBuff[sizeof(CILJit)];
return CILJitBuff;
}

DLLEXPORT ICorJitCompiler* getJit()
{
if (!g_jitInitialized)
Expand All @@ -173,7 +161,8 @@ DLLEXPORT ICorJitCompiler* getJit()

if (ILJitter == nullptr)
{
ILJitter = new (CILJitSingleton) CILJit();
alignas(alignof(CILJit)) static char CILJitBuff[sizeof(CILJit)];

@jkotas jkotas Aug 5, 2022

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Actually, is there a reason why we cannot just use a regular static CILJit singleton and just return its address here?

@jkotas jkotas Aug 5, 2022

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#73471

@jakobbotsch jakobbotsch Aug 5, 2022

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I was not sure if there were concerns with the potential static constructor or ordering with jitStartup (there is a check that initialization has run before we construct this).

@jkotas jkotas Aug 5, 2022

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CILJit constructor does close to nothing, it is just initializing the vtable. So the ordering is not a concern.

ILJitter = new (CILJitBuff, jitstd::placement_t()) CILJit();
}
return (ILJitter);
}
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