llvm-6502/lib/Target/Alpha
Dan Gohman e8be6c6391 Add a new function, ReplaceAllUsesOfValuesWith, which handles bulk
replacement of multiple values. This is slightly more efficient
than doing multiple ReplaceAllUsesOfValueWith calls, and theoretically
could be optimized even further. However, an important property of this
new function is that it handles the case where the source value set and
destination value set overlap. This makes it feasible for isel to use
SelectNodeTo in many very common cases, which is advantageous because
SelectNodeTo avoids a temporary node and it doesn't require CSEMap
updates for users of values that don't change position.

Revamp MorphNodeTo, which is what does all the work of SelectNodeTo, to
handle operand lists more efficiently, and to correctly handle a number
of corner cases to which its new wider use exposes it.

This commit also includes a change to the encoding of post-isel opcodes
in SDNodes; now instead of being sandwiched between the target-independent
pre-isel opcodes and the target-dependent pre-isel opcodes, post-isel
opcodes are now represented as negative values. This makes it possible
to test if an opcode is pre-isel or post-isel without having to know
the size of the current target's post-isel instruction set.

These changes speed up llc overall by 3% and reduce memory usage by 10%
on the InstructionCombining.cpp testcase with -fast and -regalloc=local.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53728 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-17 19:10:17 +00:00
..
Alpha.h SimpleInstructionSelector is here no more. 2008-06-25 16:38:59 +00:00
Alpha.td
AlphaAsmPrinter.cpp
AlphaBranchSelector.cpp
AlphaCodeEmitter.cpp
AlphaInstrFormats.td
AlphaInstrInfo.cpp Pool-allocation for MachineInstrs, MachineBasicBlocks, and 2008-07-07 23:14:23 +00:00
AlphaInstrInfo.h
AlphaInstrInfo.td Added MemOperands to Atomic operations since Atomics touches memory. 2008-06-25 08:15:39 +00:00
AlphaISelDAGToDAG.cpp Add a new function, ReplaceAllUsesOfValuesWith, which handles bulk 2008-07-17 19:10:17 +00:00
AlphaISelLowering.cpp Pool-allocation for MachineInstrs, MachineBasicBlocks, and 2008-07-07 23:14:23 +00:00
AlphaISelLowering.h Rather than having a different custom legalization 2008-07-04 11:47:58 +00:00
AlphaJITInfo.cpp
AlphaJITInfo.h
AlphaLLRP.cpp
AlphaRegisterInfo.cpp Pool-allocation for MachineInstrs, MachineBasicBlocks, and 2008-07-07 23:14:23 +00:00
AlphaRegisterInfo.h
AlphaRegisterInfo.td
AlphaRelocations.h
AlphaSchedule.td
AlphaSubtarget.cpp
AlphaSubtarget.h
AlphaTargetAsmInfo.cpp
AlphaTargetAsmInfo.h
AlphaTargetMachine.cpp
AlphaTargetMachine.h
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