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Fix a grammaro and clarify a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72668 91177308-0d34-0410-b5e6-96231b3b80d8
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@ -1588,11 +1588,11 @@ def : Pat<(i8 (trunc GR16:$src)),
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Requires<[In64BitMode]>;
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// h-register tricks.
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// For now, be conservative and only the extract if the value is immediately
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// zero-extended or stored, which are somewhat common cases. This uses a bunch
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// of code to prevent a register requiring a REX prefix from being allocated in
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// the same instruction as the h register, as there's currently no way to
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// describe this requirement to the register allocator.
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// For now, be conservative on x86-64 and use an h-register extract only if the
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// value is immediately zero-extended or stored, which are somewhat common
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// cases. This uses a bunch of code to prevent a register requiring a REX prefix
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// from being allocated in the same instruction as the h register, as there's
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// currently no way to describe this requirement to the register allocator.
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// h-register extract and zero-extend.
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def : Pat<(and (srl_su GR64:$src, (i8 8)), (i64 255)),
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