llvm/lib/Target/Alpha
Jim Grosbach b58f498f75 Add register-reuse to frame-index register scavenging. When a target uses
a virtual register to eliminate a frame index, it can return that register
and the constant stored there to PEI to track. When scavenging to allocate
for those registers, PEI then tracks the last-used register and value, and
if it is still available and matches the value for the next index, reuses
the existing value rather and removes the re-materialization instructions.
Fancier tracking and adjustment of scavenger allocations to keep more
values live for longer is possible, but not yet implemented and would likely
be better done via a different, less special-purpose, approach to the
problem.

eliminateFrameIndex() is modified so the target implementations can return
the registers they wish to be tracked for reuse.

ARM Thumb1 implements and utilizes the new mechanism. All other targets are
simply modified to adjust for the changed eliminateFrameIndex() prototype.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83467 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-07 17:12:56 +00:00
..
AsmPrinter Instead of printing unnecessary basic block labels as labels in 2009-10-06 17:38:38 +00:00
TargetInfo Normalize makefile comments and sort cmake file lists. 2009-08-31 13:05:24 +00:00
Alpha.h
Alpha.td
AlphaBranchSelector.cpp
AlphaCallingConv.td
AlphaCodeEmitter.cpp Update processDebugLoc() so that it can be used to process debug info before and after printing an instruction. 2009-10-06 02:19:11 +00:00
AlphaInstrFormats.td
AlphaInstrInfo.cpp
AlphaInstrInfo.h
AlphaInstrInfo.td
AlphaISelDAGToDAG.cpp Rename getTargetNode to getMachineNode, for consistency with the 2009-09-25 18:54:59 +00:00
AlphaISelLowering.cpp Tabs -> spaces, and remove trailing whitespace. 2009-09-20 02:20:51 +00:00
AlphaISelLowering.h Enhance EmitInstrWithCustomInserter() so target can specify CFG changes that sdisel will use to properly complete phi nodes. 2009-09-18 21:02:19 +00:00
AlphaJITInfo.cpp
AlphaJITInfo.h
AlphaLLRP.cpp
AlphaMachineFunctionInfo.h
AlphaMCAsmInfo.cpp
AlphaMCAsmInfo.h
AlphaRegisterInfo.cpp Add register-reuse to frame-index register scavenging. When a target uses 2009-10-07 17:12:56 +00:00
AlphaRegisterInfo.h Add register-reuse to frame-index register scavenging. When a target uses 2009-10-07 17:12:56 +00:00
AlphaRegisterInfo.td
AlphaRelocations.h
AlphaSchedule.td
AlphaSubtarget.cpp
AlphaSubtarget.h
AlphaTargetMachine.cpp
AlphaTargetMachine.h
CMakeLists.txt Normalize makefile comments and sort cmake file lists. 2009-08-31 13:05:24 +00:00
Makefile
README.txt

***

add gcc builtins for alpha instructions


***

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