sub-register indices and outputs a single super register which is formed from
a consecutive sequence of registers.
This is used as register allocation / coalescing aid and it is useful to
represent instructions that output register pairs / quads. For example,
v1024, v1025 = vload <address>
where v1024 and v1025 forms a register pair.
This really should be modelled as
v1024<3>, v1025<4> = vload <address>
but it would violate SSA property before register allocation is done.
Currently we use insert_subreg to form the super register:
v1026 = implicit_def
v1027 - insert_subreg v1026, v1024, 3
v1028 = insert_subreg v1027, v1025, 4
...
= use v1024
= use v1028
But this adds pseudo live interval overlap between v1024 and v1025.
We can now modeled it as
v1024, v1025 = vload <address>
v1026 = REG_SEQUENCE v1024, 3, v1025, 4
...
= use v1024
= use v1026
After coalescing, it will be
v1026<3>, v1025<4> = vload <address>
...
= use v1026<3>
= use v1026
llvm-svn: 102815
code. It used to #include the enhanced disassembly
information for the targets it supported straight
out of lib/Target/{X86,ARM,...} but now it uses a
new interface provided by MCDisassembler, and (so
far) implemented by X86 and ARM.
Also removed hacky #define-controlled initialization
of targets in edis. If clients only want edis to
initialize a limited set of targets, they can set
--enable-targets on the configure command line.
llvm-svn: 101179
We are bound to fail! For proper disassembly, the well-known encoding bits
of the instruction must be fully specified.
This also removes pseudo instructions from considerations of disassembly,
which is a better design and less fragile than the name matchings.
llvm-svn: 100899
such that the non-VFP versions have no implicit defs of VFP registers.
If any callee-saved VFP registers are marked as having been defined, the
prologue/epilogue code will try to save and restore them.
Radar 7770432.
llvm-svn: 100892
I also added a rule to the ARM target's Makefile to
build the ARM-specific instruction information table
for the enhanced disassembler.
I will add the test harness for all this stuff in
a separate commit.
llvm-svn: 100735
argument that had to be between 0 and 7 to have any value,
firing an assert later in the AsmPrinter. Now, the
disassembler rejects instructions with out-of-range values
for that immediate.
llvm-svn: 100694
When a target instruction wants to set target-specific flags, it should simply
set bits in the TSFlags bit vector defined in the Instruction TableGen class.
This works well because TableGen resolves member references late:
class I : Instruction {
AddrMode AM = AddrModeNone;
let TSFlags{3-0} = AM.Value;
}
let AM = AddrMode4 in
def ADD : I;
TSFlags gets the expected bits from AddrMode4 in this example.
llvm-svn: 100384
backend (ARMDecoderEmitter) which emits the decoder functions for ARM and Thumb,
and the disassembler core which invokes the decoder function and builds up the
MCInst based on the decoded Opcode.
Reviewed by Chris Latter and Bob Wilson.
llvm-svn: 100233
doesn't need to be stable because the patterns are fully ordered.
Add a first level sort predicate that orders patterns in this
order: 1) scalar integer operations 2) scalar floating point
3) vector int 4) vector float. This is a trivial sort on their
top level pattern type so it is nice and transitive. The
benefit of doing this is that simple integer operations are
much more common than insane vector things and isel was trying
to match the big complex vector patterns before the simple
ones because the complexity of the vector operations was much
higher. Since they can't both match, it is best (for compile
time) to try the simple integer ones first.
This cuts down the # failed match attempts on real code by
quite a bit, for example, this reduces backtracks on crafty
(as a random example) from 228285 -> 188369.
llvm-svn: 99797
patterns within the generated matcher. This works great except
that the sort fails because the relation defined isn't
transitive. I have a much simpler solution coming next, but want
to archive the code.
llvm-svn: 99795
and those derived from them. These are obnoxious because
they were written as: PatLeaf<(bitconvert). Not having an
argument was foiling adding better type checking for operand
count matching up with what was required (in this case,
bitconvert always requires an operand!)
llvm-svn: 99759
transforming it into (add (i32 GPR), 4). This allows us to write type
generic multi patterns and have tblgen automatically drop the bitconvert
in the case when the types align. This allows us to fold an extra load
in the changed testcase.
llvm-svn: 99756
