take multiple cycles to decode.
For the current if-converter clients (actually only ARM), the instructions that
are predicated on false are not nops. They would still take machine cycles to
decode. Micro-coded instructions such as LDM / STM can potentially take multiple
cycles to decode. If-converter should take treat them as non-micro-coded
simple instructions.
llvm-svn: 113570
they already have one.
This fixes the himenobmtxpa miscompilation on ARM.
The PostRA scheduler got confused by the double memoperand and hoisted a stack
slot load above a store to the same slot.
llvm-svn: 108219
Targets must now implement TargetInstrInfo::copyPhysReg instead. There is no
longer a default implementation forwarding to copyRegToReg.
llvm-svn: 108095
inserted in a MBB, and return an already inserted MI.
This target API change is necessary to allow foldMemoryOperand to call
storeToStackSlot and loadFromStackSlot when folding a COPY to a stack slot
reference in a target independent way.
The foldMemoryOperandImpl hook is going to change in the same way, but I'll wait
until COPY folding is actually implemented. Most targets only fold copies and
won't need to specialize this hook at all.
llvm-svn: 107991
This target hook is intended to replace copyRegToReg entirely, but for now it
calls copyRegToReg.
Any remaining calls to copyRegToReg wil be replaced by COPY instructions.
llvm-svn: 107854
- This fixed a number of bugs in if-converter, tail merging, and post-allocation
scheduler. If-converter now runs branch folding / tail merging first to
maximize if-conversion opportunities.
- Also changed the t2IT instruction slightly. It now defines the ITSTATE
register which is read by instructions in the IT block.
- Added Thumb2 specific hazard recognizer to ensure the scheduler doesn't
change the instruction ordering in the IT block (since IT mask has been
finalized). It also ensures no other instructions can be scheduled between
instructions in the IT block.
This is not yet enabled.
llvm-svn: 106344
instruction defines subregisters.
Any existing subreg indices on the original instruction are preserved or
composed with the new subreg index.
Also substitute multiple operands mentioning the original register by using the
new MachineInstr::substituteRegister() function. This is necessary because there
will soon be <imp-def> operands added to non read-modify-write partial
definitions. This instruction:
%reg1234:foo = FLAP %reg1234<imp-def>
will reMaterialize(%reg3333, bar) like this:
%reg3333:bar-foo = FLAP %reg333:bar<imp-def>
Finally, replace the TargetRegisterInfo pointer argument with a reference to
indicate that it cannot be NULL.
llvm-svn: 105358
- Eliminate TargetInstrInfo::isIdentical and replace it with produceSameValue. In the default case, produceSameValue just checks whether two machine instructions are identical (except for virtual register defs). But targets may override it to check for unusual cases (e.g. ARM pic loads from constant pools).
llvm-svn: 97628
except it doesn't care if the definitions' virtual registers differ. This is
used by machine LICM and other MI passes to perform CSE.
- Teach Thumb2InstrInfo::isIdentical() to check two t2LDRpci_pic are identical.
Since pc relative constantpool entries are always different, this requires it
it check if the values can actually the same.
llvm-svn: 86328
stack slots and giving them different PseudoSourceValue's did not fix the
problem of post-alloc scheduling miscompiling llvm itself.
- Apply Dan's conservative workaround by assuming any non fixed stack slots can
alias other memory locations. This means a load from spill slot #1 cannot
move above a store of spill slot #2.
- Enable post-alloc scheduling for x86 at optimization leverl Default and above.
llvm-svn: 84424
bootstrap of FSF-style PPC, so there is some
reason to believe the original bug (which was
never analyzed) has been fixed, probably by
82266.
llvm-svn: 83871
is trivially rematerializable and integrate it into
TargetInstrInfo::isTriviallyReMaterializable. This way, all places that
need to know whether an instruction is rematerializable will get the
same answer.
This enables the useful parts of the aggressive-remat option by
default -- using AliasAnalysis to determine whether a memory location
is invariant, and removes the questionable parts -- rematting operations
with virtual register inputs that may not be live everywhere.
llvm-svn: 83687
Evan Cheng
Chris Lattner
Jakob Stoklund Olesen
Dale Johannesen
Dan Gohman