There were a number of issues to fix up here:
* The "device" argument of the llvm.memory.barrier intrinsic should be
used to distinguish the "Full System" domain from the "Inner Shareable"
domain. It has nothing to do with using DMB vs. DSB instructions.
* The compiler should never need to emit DSB instructions. Remove the
ARMISD::SYNCBARRIER node and also remove the instruction patterns for DSB.
* Merge the separate DMB/DSB instructions for options only used for the
disassembler with the default DMB/DSB instructions. Add the default
"full system" option ARM_MB::SY to the ARM_MB::MemBOpt enum.
* Add a separate ARMISD::MEMBARRIER_MCR node for subtargets that implement
a data memory barrier using the MCR instruction.
* Fix up encodings for these instructions (except MCR).
I also updated the tests and added a few new ones to check for DMB options
that were not currently being exercised.
llvm-svn: 117756
just
.type foo,@object
will produce an undefined reference to foo. On the other hand, a file with
just
.weakref bar, foo
will not. It is somewhat hard to support both in MC since both statements
should create the symbols. It should be possible if we really need to by
adding to the flags, but hopefully that is not necessary.
With this patch we do not produce a undefined reference in any of those cases.
The assembly file needs an actual use for the undefined reference to be
present.
This is in preparation for a patch implementing .weakref.
llvm-svn: 117735
This code had previously used 2*N, where N is the mask length, to represent
undef. That is not safe because the shufflevector operands may have more
than N elements -- they don't have to match the result type.
llvm-svn: 117721
Allow splats even if they don't match either of the original shuffles,
possibly due to undef entries in the shuffles masks. Radar 8597790.
Also fix some 80-column violations.
llvm-svn: 117719
needs to be guaranteed never to be run on an unreachable block. However, earlier block simplifications may have
changed the CFG to make block that were reachable when we began our iteration unreachable by the time we try to
simplify them. (Note that this also means that our depth-first iterators were potentially being invalidated).
This should not have a large impact on code quality, since later runs of instcombine should pick up these simplifications.
Fixes PR8506.
llvm-svn: 117709
operand and one of them has a single use that is a live out copy, favor the
one that is live out. Otherwise it will be difficult to eliminate the copy
if the instruction is a loop induction variable update. e.g.
BB:
sub r1, r3, #1
str r0, [r2, r3]
mov r3, r1
cmp
bne BB
=>
BB:
str r0, [r2, r3]
sub r3, r3, #1
cmp
bne BB
This fixed the recent 256.bzip2 regression.
llvm-svn: 117675
We don't want unused values forming their own equivalence classes, so we lump
them all together in one class, and then merge them with the class of the last
used value.
llvm-svn: 117670
* If we have a M or a G, reject sections without the type
* Only parse the flag specific arguments if we have M or G
* Parse the corresponding arguments for M and G
We ignore the G arguments and flag for now.
llvm-svn: 117608
in SSAUpdaterImpl.h
Verifying live intervals revealed that the old method was completely wrong, and
we need an iterative approach to calculating PHI placemant. Fortunately, we have
MachineDominators available, so we don't have to compute that over and over
like SSAUpdaterImpl.h must.
Live-out values are cached between calls to mapValue() and computed in a greedy
way, so most calls will be working with very small block sets.
Thanks to Bob for explaining how this should work.
llvm-svn: 117599
proper SSA updating.
This doesn't cause MachineDominators to be recomputed since we are already
requiring MachineLoopInfo which uses dominators as well.
llvm-svn: 117598
which contains slashes is inconsistent with the meaning of PATH on
Unix-type platforms, and pretty surprising.
If the user has given a specific path to execute and we can't
execute it, we should fail and say why. (Apparently the new
posix_spawn code doesn't always say why, but that's a separate
issue.)
llvm-svn: 117596
Original commit message:
On "Unix", if Program::FindProgramByName is given a name containing
slashes, just go with it, regardless of whether it looks like it will
be executable. This follows the behavior of sh(1) more closely.
It's better when behaviour is consistent between platforms. This change also
makes FindExecutable() behave as expected on unix-likes (before this commit, it
used to always succeed).
llvm-svn: 117582
- For now, loads of [r, r] addressing mode is the same as the
[r, r lsl/lsr/asr #] variants. ARMBaseInstrInfo::getOperandLatency() should
identify the former case and reduce the output latency by 1.
- Also identify [r, r << 2] case. This special form of shifter addressing mode
is "free".
llvm-svn: 117519
