Start a README.txt of possible optimizations to do in IRgen.
llvm-svn: 59130
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IRgen optimization opportunities.
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//===---------------------------------------------------------------------===//
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The common pattern of
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--
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short x; // or char, etc
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(x == 10)
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--
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generates an zext/sext of x which can easily be avoided.
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//===---------------------------------------------------------------------===//
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Bitfields accesses can be shifted to simplify masking and sign
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extension. For example, if the bitfield width is 8 and it is
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appropriately aligned then is is a lot shorter to just load the char
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directly.
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//===---------------------------------------------------------------------===//
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Bitfields should not reload the stored value just to return the
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correct result.
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//===---------------------------------------------------------------------===//
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