useAA significantly improves the handling of vector code that has TBAA
information attached. It also helps other cases, as shown by the testsuite
changes here. The only real downside I've seen is that it interferes with
MergeConsecutiveStores. The problem is that that optimization works top
down, starting at the first store in the chain, and looks for cases where
the chain result is only used by a single related store. These related
stores don't alias, so useAA will have rewritten all the later stores to
use a different chain input (typically the same one as the first store).
I think the advantages outweigh the disadvantages though, so for now I've
just disabled alias analysis for the unaligned-01.ll test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193521 91177308-0d34-0410-b5e6-96231b3b80d8
The input to an RxSBG operation can be narrower as long as the upper bits
are don't care. This fixes a FIXME added in r192783.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192790 91177308-0d34-0410-b5e6-96231b3b80d8
We previously used the default expansion to SELECT_CC, which in turn would
expand to "LHI; BRC; LHI". In most cases it's better to use an IPM-based
sequence instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192784 91177308-0d34-0410-b5e6-96231b3b80d8
This patch fixes an old FIXME by creating a MCTargetStreamer interface
and moving the target specific functions for ARM, Mips and PPC to it.
The ARM streamer is still declared in a common place because it is
used from lib/CodeGen/ARMException.cpp, but the Mips and PPC are
completely hidden in the corresponding Target directories.
I will send an email to llvmdev with instructions on how to use this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192181 91177308-0d34-0410-b5e6-96231b3b80d8
There are no corresponding patterns for small immediates because they would
prevent the use of fused compare-and-branch instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191775 91177308-0d34-0410-b5e6-96231b3b80d8
Floats are stored in the high 32 bits of an FPR, and the only GPR<->FPR
transfers are full-register transfers. This patch optimizes GPR<->FPR
float transfers when the high word of a GPR is directly accessible.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191764 91177308-0d34-0410-b5e6-96231b3b80d8
Similar to low words, we can use the shorter LLIHL and LLIHH if it turns
out that the other half of the GR64 isn't live.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191750 91177308-0d34-0410-b5e6-96231b3b80d8
This just adds the basics necessary for allocating the upper words to
virtual registers (move, load and store). The move support is parameterised
in a way that makes it easy to handle zero extensions, but the associated
zero-extend patterns are added by a later patch.
The easiest way of testing this seemed to be add a new "h" register
constraint for high words. I don't expect the constraint to be useful
in real inline asms, but it should work, so I didn't try to hide it
behind an option.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191739 91177308-0d34-0410-b5e6-96231b3b80d8
Originally committed as r191661, but reverted because it changed the matching
order of comparisons on some hosts. That should have been fixed by r191735.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191738 91177308-0d34-0410-b5e6-96231b3b80d8
For some reason, adding definitions for these load and store
instructions changed whether some of the build bots matched
comparisons as signed or unsigned.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191663 91177308-0d34-0410-b5e6-96231b3b80d8
The only thing this does on its own is make the definitions of RISB[HL]G
a bit more precise. Those instructions are only used by the MC layer at
the moment, so no behavioral change is intended. The class is needed by
later patches though.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191660 91177308-0d34-0410-b5e6-96231b3b80d8
Use subreg_hNN and subreg_lNN for the high and low NN bits of a register.
List the low registers first, so that subreg_l32 also means the low 32
bits of a 128-bit register.
Floats are stored in the upper 32 bits of a 64-bit register, so they
should use subreg_h32 rather than subreg_l32.
No behavioral change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191659 91177308-0d34-0410-b5e6-96231b3b80d8
I'm about to add support for high-word operations, so it seemed better
for the low-word registers to have names like R0L rather than R0W.
No behavioral change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191655 91177308-0d34-0410-b5e6-96231b3b80d8
The backend tries to use block operations like MVC, NC, OC and XC for
simple scalar operations. For correctness reasons, it rejects any case
in which the regions might partially overlap. However, for performance
reasons, it should also reject cases where the regions might be equal,
since the instruction might then not use the fast path.
This fixes a performance regression seen in bzip2. We may want to limit
the optimisation even more in future, or even remove it entirely, but I'll
try with this for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191525 91177308-0d34-0410-b5e6-96231b3b80d8
The backend previously folded offsets into PC-relative addresses
whereever possible. That's the right thing to do when the address
can be used directly in a PC-relative memory reference (using things
like LRL). But if we have a register-based memory reference and need
to load the PC-relative address separately, it's better to use an anchor
point that could be shared with other accesses to the same area of the
variable.
Fixes a FIXME.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191524 91177308-0d34-0410-b5e6-96231b3b80d8
Another patch to avoid duplication of encoding information. Things like
NILF, NILL and NILH are used as both 32-bit and 64-bit instructions.
Here the 64-bit versions are defined as aliases of the 32-bit ones.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191369 91177308-0d34-0410-b5e6-96231b3b80d8
Similar to r191364, but for calls. This patch also removes the shortening
of BRASL to BRAS within a TU. Doing that was a bit controversial internally,
since there's a strong expectation with the z assembler that WYWIWYG.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191366 91177308-0d34-0410-b5e6-96231b3b80d8
Another patch to reduce the duplication of encoding information.
Rather than define separate patterns for truncating 64-bit stores,
use the 32-bit stores with a subreg. No behavioral changed intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191365 91177308-0d34-0410-b5e6-96231b3b80d8
This is the first of a few patches to reduce the dupliation of encoding
information. The return instruction is a normal BR in which one of the
registers is fixed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191364 91177308-0d34-0410-b5e6-96231b3b80d8
When loading immediates into a GR32, the port prefered LHI, followed by
LLILH or LLILL, followed by IILF. LHI and IILF are natural 32-bit
operations, but LLILH and LLILL also clear the upper 32 bits of the register.
This was represented as taking a 32-bit subreg of a 64-bit assignment.
Using subregs for something as simple as a move immediate was probably
a bad idea. Also, I have patches to add support for the high-word facility,
and we don't want something like LLILH and LLILL to stop the high word of
the same GPR from being used.
This patch therefore uses LHI and IILF to begin with and adds a late
machine-specific pass to use LLILH and LLILL if the other half of the
register is not live. The high-word patches extend this behavior to
IIHF, LLIHL and LLIHH.
No behavioral change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191363 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, the DAGISel function WalkChainUsers was spotting that it
had entered already-selected territory by whether a node was a
MachineNode (amongst other things). Since it's fairly common practice
to insert MachineNodes during ISelLowering, this was not the correct
check.
Looking around, it seems that other nodes get their NodeId set to -1
upon selection, so this makes sure the same thing happens to all
MachineNodes and uses that characteristic to determine whether we
should stop looking for a loop during selection.
This should fix PR15840.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191165 91177308-0d34-0410-b5e6-96231b3b80d8
For some reason I never got around to adding these at the same time as
the signed versions. No idea why.
I'm not sure whether this SystemZII::BranchC* stuff is useful, or whether
it should just be replaced with an "is normal" flag. I'll leave that
for later though.
There are some boundary conditions that can be tweaked, such as preferring
unsigned comparisons for equality with [128, 256), and "<= 255" over "< 256",
but again I'll leave those for a separate patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190930 91177308-0d34-0410-b5e6-96231b3b80d8
The port originally had special patterns for extload, mapping them to the
same instructions as sextload. It seemed neater to have patterns that
match "an extension that is allowed to be signed" and "an extension that
is allowed to be unsigned".
This was originally meant to be a clean-up, but it does improve the handling
of promoted integers a little, as shown by args-06.ll.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190777 91177308-0d34-0410-b5e6-96231b3b80d8
The 'Deprecated' class allows you to specify a SubtargetFeature that the
instruction is deprecated on.
The 'ComplexDeprecationPredicate' class allows you to define a custom
predicate that is called to check for deprecation.
For example:
ComplexDeprecationPredicate<"MCR">
would mean you would have to define the following function:
bool getMCRDeprecationInfo(MCInst &MI, MCSubtargetInfo &STI,
std::string &Info)
Which returns 'false' for not deprecated, and 'true' for deprecated
and store the warning message in 'Info'.
The MCTargetAsmParser constructor was chaned to take an extra argument of
the MCInstrInfo class, so out-of-tree targets will need to be changed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190598 91177308-0d34-0410-b5e6-96231b3b80d8
