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			31 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
Date: Wed, 20 Jun 2001 12:32:22 -0500
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From: Vikram Adve <vadve@cs.uiuc.edu>
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To: Chris Lattner <lattner@cs.uiuc.edu>
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Subject: .NET vs. our VM
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One significant difference between .NET CLR and our VM is that the CLR
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includes full information about classes and inheritance.  In fact, I just
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sat through the paper on adding templates to .NET CLR, and the speaker
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indicated that the goal seems to be to do simple static compilation (very
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little lowering or optimization).  Also, the templates implementation in CLR
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"relies on dynamic class loading and JIT compilation".
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This is an important difference because I think there are some significant
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advantages to have a much lower level VM layer, and do significant static
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analysis and optimization.
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I also talked to the lead guy for KAI's C++ compiler (Arch Robison) and he
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said that SGI and other commercial compilers have included options to export
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their *IR* next to the object code (i.e., .il files) and use them for
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link-time code generation.  In fact, he said that the .o file was nearly
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empty and was entirely generated from the .il at link-time.  But he agreed
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that this limited the link-time interprocedural optimization to modules
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compiled by the same compiler, whereas our approach allows us to link and
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optimize modules from multiple different compilers.  (Also, of course, they
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don't do anything for runtime optimization).
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All issues to bring up in Related Work.
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--Vikram
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