Evan Cheng a347f85dbe Starting to refactor Target to separate out code that's needed to fully describe
target machine from those that are only needed by codegen. The goal is to
sink the essential target description into MC layer so we can start building
MC based tools without needing to link in the entire codegen.

First step is to refactor TargetRegisterInfo. This patch added a base class
MCRegisterInfo which TargetRegisterInfo is derived from. Changed TableGen to
separate register description from the rest of the stuff.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133782 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-24 01:44:41 +00:00
..

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add gcc builtins for alpha instructions


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custom expand byteswap into nifty 
extract/insert/mask byte/word/longword/quadword low/high
sequences

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see if any of the extract/insert/mask operations can be added

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match more interesting things for cmovlbc cmovlbs (move if low bit clear/set)

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lower srem and urem

remq(i,j):  i - (j * divq(i,j)) if j != 0
remqu(i,j): i - (j * divqu(i,j)) if j != 0
reml(i,j):  i - (j * divl(i,j)) if j != 0
remlu(i,j): i - (j * divlu(i,j)) if j != 0

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add crazy vector instructions (MVI):

(MIN|MAX)(U|S)(B8|W4) min and max, signed and unsigned, byte and word
PKWB, UNPKBW pack/unpack word to byte
PKLB UNPKBL pack/unpack long to byte
PERR pixel error (sum across bytes of bytewise abs(i8v8 a - i8v8 b))

cmpbytes bytewise cmpeq of i8v8 a and i8v8 b (not part of MVI extensions)

this has some good examples for other operations that can be synthesised well 
from these rather meager vector ops (such as saturating add).
http://www.alphalinux.org/docs/MVI-full.html