Sometimes you can learn a lot during reading source .NET. Let's open the source code of a Decimal constructor from .NET Reference Source (mscorlib/system/decimal.cs,158):
// Constructs a Decimal from an integer value.
//
public Decimal(int value) {
// JIT today can't inline methods that contains "starg" opcode.
// For more details, see DevDiv Bugs 81184: x86 JIT CQ: Removing the inline striction of "starg".
int value_copy = value;
if (value_copy >= 0) {
flags = 0;
}
else {
flags = SignMask;
value_copy = -value_copy;
}
lo = value_copy;
mid = 0;
hi = 0;
}
The comment states that JIT-x86 can't apply the inlining optimization for a method that contains the starg IL-opcode. Curious, is not it?
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