Chris Lattner 968ff11967 Change SectionKind to be a property that is true of a *section*, it
should have no state that is specific to particular globals in the
section.  In this case, it means the removal of the "isWeak" and
"ExplicitSection" bits.  MCSection uses the new form of SectionKind.

To handle isWeak, I introduced a new SectionInfo class, which is
SectionKind + isWeak, and it is used by the part of the code generator
that does classification of a specific global.

The ExplicitSection disappears.  It is moved onto MCSection as a new
"IsDirective" bit.  Since the Name of a section is either a section
or directive, it makes sense to keep this bit in MCSection.  Ultimately
the creator of MCSection should canonicalize (e.g.) .text to whatever
the actual section is.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77803 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-01 21:11:14 +00:00
..
2009-06-25 18:13:04 +00:00
2009-07-19 01:33:04 +00:00
2009-07-19 01:33:04 +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

***

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

***

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

***

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

***

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 accross bytes of bytewise abs(i8v8 a - i8v8 b))

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

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