问题
In Visual Studio C/C++ projects, it's easy to modify compiler's optimization settings in "Property Pages | C/C++ | Optimization". For example, we may give different optimization levels such as /O2 and /O3, as well as advanced optimizations like "Omit Frame Pointers".
However, I can't simply find corresponding UIs in C# project of Visual Studio. All I can find is just turning off optimizations: the "Optimize code" check box is all I've got.
Can C# users control detailed compiler's optimizations like C/C++? Do I have to give compiler options in command line?
回答1:
Much of the optimisation of C# code goes on at the JIT compiler level, rather than the C# compiler. Basically there are no such detailed settings as the ones available in C or C++.
There are a few performance-related elements of the runtime that can be tweaked, such as GC strategies, but not a great deal.
When I'm building benchmark tests etc from the command line I tend to just use something like this:
csc /o+ /debug- Test.cs
(I believe I have seen the presence of a matching pdb file make a difference to performance, possibly in terms of the cost of exceptions being thrown, hence the debug-
switch... but I could be wrong.)
EDIT: If you want to see the difference each bit of optimization makes, there's one approach which could prove interesting:
- Compile the same code with and without optimization
- Use ildasm or Reflector in IL mode to see what the differences are
- Apply the same changes one at a time manually (using ilasm) and measure how much each one has
回答2:
AFAIK C# compiler has no such detailed optimization properties. Probably optimization is either enabled or disabled.
http://msdn.microsoft.com/en-us/library/6s2x2bzy.aspx
I found just two:
/filealign
Specifies the size of sections in the output file./optimize
Enables/disables optimizations.
回答3:
A bit OT, but someone looking at this question might find this useful:
Adding this to method signature: [MethodImpl(MethodImplOptions.NoOptimization)]
turns off compiler optimizations for that method.
See here for details: https://msdn.microsoft.com/en-us/library/system.runtime.compilerservices.methodimploptions%28v=vs.110%29.aspx?f=255&MSPPError=-2147217396
来源:https://stackoverflow.com/questions/3226157/where-can-i-modify-detailed-c-sharp-compiler-optimization-settings-in-visual-stu