Fix a grammaro and clarify a comment.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72668 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2009-05-31 17:52:18 +00:00
parent 18a69c5a36
commit 2d98f0664b

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