Since the LTxBRCompare instructions can't be used with vector registers, a
normal load-and-test instruction (with a modelled def operand) is used instead.
Reviewed by Ulrich Weigand.
llvm-svn: 249664
Recent mesa/llvmpipe crashes on SystemZ due to a failed assertion when
attempting to compile a routine with a return type of
{ <4 x float>, <4 x float>, <4 x float>, <4 x float> }
on a system without vector instruction support.
This is because after legalizing the vector type, we get a return value
consisting of 16 floats, which cannot all be returned in registers.
Usually, what should happen in this case is that the target's CanLowerReturn
routine rejects the return type, in which case SelectionDAG falls back to
implementing a structure return in memory via implicit reference.
However, the SystemZ target never actually implemented any CanLowerReturn
routine, and thus would accept any struct return type.
This patch fixes the crash by implementing CanLowerReturn. As a side effect,
this also handles fp128 return values, fixing a todo that was noted in
SystemZCallingConv.td.
llvm-svn: 244889
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
Reviewers: echristo
Subscribers: jholewinski, llvm-commits, rafael, yaron.keren
Differential Revision: http://reviews.llvm.org/D11040
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 241778
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
Reviewers: echristo
Subscribers: jholewinski, llvm-commits, rafael, yaron.keren
Differential Revision: http://reviews.llvm.org/D11037
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 241776
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
Reviewers: echristo
Subscribers: jholewinski, ted, yaron.keren, rafael, llvm-commits
Differential Revision: http://reviews.llvm.org/D11028
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 241775
There is some functional change here because it changes target code from
atoi(3) to StringRef::getAsInteger which has error checking. For valid
constraints there should be no difference.
llvm-svn: 241411
This is important because of different addressing modes
depending on the address space for GPU targets.
This only adds the argument, and does not update
any of the uses to provide the correct address space.
llvm-svn: 238723
This adds intrinsics to allow access to all of the z13 vector instructions.
Note that instructions whose semantics can be described by standard LLVM IR
do not get any intrinsics.
For each instructions whose semantics *cannot* (fully) be described, we
define an LLVM IR target-specific intrinsic that directly maps to this
instruction.
For instructions that also set the condition code, the LLVM IR intrinsic
returns the post-instruction CC value as a second result. Instruction
selection will attempt to detect code that compares that CC value against
constants and use the condition code directly instead.
Based on a patch by Richard Sandiford.
llvm-svn: 236527
The ABI allows sub-128 vectors to be passed and returned in registers,
with the vector occupying the upper part of a register. We therefore
want to legalize those types by widening the vector rather than promoting
the elements.
The patch includes some simple tests for sub-128 vectors and also tests
that we can recognize various pack sequences, some of which use sub-128
vectors as temporary results. One of these forms is based on the pack
sequences generated by llvmpipe when no intrinsics are used.
Signed unpacks are recognized as BUILD_VECTORs whose elements are
individually sign-extended. Unsigned unpacks can have the equivalent
form with zero extension, but they also occur as shuffles in which some
elements are zero.
Based on a patch by Richard Sandiford.
llvm-svn: 236525
The architecture doesn't really have any native v4f32 operations except
v4f32->v2f64 and v2f64->v4f32 conversions, with only half of the v4f32
elements being used. Even so, using vector registers for <4 x float>
and scalarising individual operations is much better than generating
completely scalar code, since there's much less register pressure.
It's also more efficient to do v4f32 comparisons by extending to 2
v2f64s, comparing those, then packing the result.
This particularly helps with llvmpipe.
Based on a patch by Richard Sandiford.
llvm-svn: 236523
This adds ABI and CodeGen support for the v2f64 type, which is natively
supported by z13 instructions.
Based on a patch by Richard Sandiford.
llvm-svn: 236522
This the first of a series of patches to add CodeGen support exploiting
the instructions of the z13 vector facility. This patch adds support
for the native integer vector types (v16i8, v8i16, v4i32, v2i64).
When the vector facility is present, we default to the new vector ABI.
This is characterized by two major differences:
- Vector types are passed/returned in vector registers
(except for unnamed arguments of a variable-argument list function).
- Vector types are at most 8-byte aligned.
The reason for the choice of 8-byte vector alignment is that the hardware
is able to efficiently load vectors at 8-byte alignment, and the ABI only
guarantees 8-byte alignment of the stack pointer, so requiring any higher
alignment for vectors would require dynamic stack re-alignment code.
However, for compatibility with old code that may use vector types, when
*not* using the vector facility, the old alignment rules (vector types
are naturally aligned) remain in use.
These alignment rules are not only implemented at the C language level
(implemented in clang), but also at the LLVM IR level. This is done
by selecting a different DataLayout string depending on whether the
vector ABI is in effect or not.
Based on a patch by Richard Sandiford.
llvm-svn: 236521
We already exploit a number of instructions specific to z196,
but not yet POPCNT. Add support for the population-count
facility, MC support for the POPCNT instruction, CodeGen
support for using POPCNT, and implement the getPopcntSupport
TargetTransformInfo hook.
llvm-svn: 233689
This hooks up the TargetTransformInfo machinery for SystemZ,
and provides an implementation of getIntImmCost.
In addition, the patch adds the isLegalICmpImmediate and
isLegalAddImmediate TargetLowering overrides, and updates
a couple of test cases where we now generate slightly
better code.
llvm-svn: 233688
Summary:
But still handle them the same way since I don't know how they differ on
this target.
No functional change intended.
Reviewers: uweigand
Reviewed By: uweigand
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8251
llvm-svn: 232495
Summary:
This is instead of doing this in target independent code and is the last
non-functional change before targets begin to distinguish between
different memory constraints when selecting code for the ISD::INLINEASM
node.
Next, each target will individually move away from the idea that all
memory constraints behave like 'm'.
Subscribers: jholewinski, llvm-commits
Differential Revision: http://reviews.llvm.org/D8173
llvm-svn: 232373
a lookup, pass that in rather than use a naked call to getSubtargetImpl.
This involved passing down and around either a TargetMachine or
TargetRegisterInfo. Update all callers/definitions around the targets
and SelectionDAG.
llvm-svn: 230699
The current SystemZ back-end only supports the local-exec TLS access model.
This patch adds all required CodeGen support for the other TLS models, which
means in particular:
- Expand initial-exec TLS accesses by loading TLS offsets from the GOT
using @indntpoff relocations.
- Expand general-dynamic and local-dynamic accesses by generating the
appropriate calls to __tls_get_offset. Note that this routine has
a non-standard ABI and requires loading the GOT pointer into %r12,
so the patch also adds support for the GLOBAL_OFFSET_TABLE ISD node.
- Add a new platform-specific optimization pass to remove redundant
__tls_get_offset calls in the local-dynamic model (modeled after
the corresponding X86 pass).
- Add test cases verifying all access models and optimizations.
llvm-svn: 229654
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)
Changes made by clang-tidy with minor tweaks.
llvm-svn: 215558
Rename to allowsMisalignedMemoryAccess.
On R600, 8 and 16 byte accesses are mostly OK with 4-byte alignment,
and don't need to be split into multiple accesses. Vector loads with
an alignment of the element type are not uncommon in OpenCL code.
llvm-svn: 214055
The target was marking SIGN_EXTEND as Custom because it wanted to optimize
certain sign-extended shifts. In all other respects the extension is Legal,
so it'd be better to do the optimization in PerformDAGCombine instead.
No functional change intended.
llvm-svn: 203234
...into (ashr (shl (anyext X), ...), ...), which requires one fewer
instruction. The (anyext X) can sometimes be simplified too.
I didn't do this in DAGCombiner because widening shifts isn't a win
on all targets.
llvm-svn: 199114
...namely LOAD AND ADD, LOAD AND AND, LOAD AND OR and LOAD AND EXCLUSIVE OR.
LOAD AND ADD LOGICAL isn't really separately useful for LLVM.
I'll look at adding reusing the CC results in new year.
llvm-svn: 197985
This patch makes more use of LPGFR and LNGFR. It builds on top of
the LTGFR selection from r197234. Most of the tests are motivated
by what InstCombine would produce.
llvm-svn: 197236
One unusual feature of the z architecture is that the result of a
previous load can be reused indefinitely for subsequent loads, even if
a cache-coherent store to that location is performed by another CPU.
A special serializing instruction must be used if you want to force
a load to be reattempted.
Since volatile loads are not supposed to be omitted in this way,
we should insert a serializing instruction before each such load.
The same goes for atomic loads.
The patch implements this at the IR->DAG boundary, in a similar way
to atomic fences. It is a no-op for targets other than SystemZ.
llvm-svn: 196906
One unusual feature of the z architecture is that the result of a
previous load can be reused indefinitely for subsequent loads, even if
a cache-coherent store to that location is performed by another CPU.
A special serializing instruction must be used if you want to force
a load to be reattempted.
Since volatile loads are not supposed to be omitted in this way,
we should insert a serializing instruction before each such load.
The same goes for atomic loads.
The patch implements this at the IR->DAG boundary, in a similar way
to atomic fences. It is a no-op for targets other than SystemZ.
llvm-svn: 196905
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.
llvm-svn: 192784
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.
llvm-svn: 191524
The main complication here is that TM and TMY (the memory forms) set
CC differently from the register forms. When the tested bits contain
some 0s and some 1s, the register forms set CC to 1 or 2 based on the
value the uppermost bit. The memory forms instead set CC to 1
regardless of the uppermost bit.
Until now, I've tried to make it so that a branch never tests for an
impossible CC value. E.g. NR only sets CC to 0 or 1, so branches on the
result will only test for 0 or 1. Originally I'd tried to do the same
thing for TM and TMY by using custom matching code in ISelDAGToDAG.
That ended up being very ugly though, and would have meant duplicating
some of the chain checks that the common isel code does.
I've therefore gone for the simpler alternative of adding an extra
operand to the TM DAG opcode to say whether a memory form would be OK.
This means that the inverse of a "TM;JE" is "TM;JNE" rather than the
more precise "TM;JNLE", just like the inverse of "TMLL;JE" is "TMLL;JNE".
I suppose that's arguably less confusing though...
llvm-svn: 190400
The architecture has many comparison instructions, including some that
extend one of the operands. The signed comparison instructions use sign
extensions and the unsigned comparison instructions use zero extensions.
In cases where we had a free choice between signed or unsigned comparisons,
we were trying to decide at lowering time which would best fit the available
instructions, taking things like extension type into account. The code
to do that was getting increasingly hairy and was also making some bad
decisions. E.g. when comparing the result of two LLCs, it is better to use
CR rather than CLR, since CR can be fused with a branch while CLR can't.
This patch removes the lowering code and instead adds an operand to
integer comparisons to say whether signed comparison is required,
whether unsigned comparison is required, or whether either is OK.
We can then leave the choice of instruction up to the normal isel code.
llvm-svn: 190138
For now just handles simple comparisons of an ANDed value with zero.
The CC value provides enough information to do any comparison for a
2-bit mask, and some nonzero comparisons with more populated masks,
but that's all future work.
llvm-svn: 189469
Lengths up to a certain threshold (currently 6 * 256) use a series of MVCs.
Lengths above that threshold use a loop to handle X*256 bytes followed
by a single MVC to handle the excess (if any). This loop will also be
needed in future when support for variable lengths is added.
Because the same tablegen classes are used to define MVC and CLC,
the patch also has the side-effect of defining a pseudo loop instruction
for CLC. That instruction isn't used yet (and wouldn't be handled correctly
if it were). I'm planning to use it soon though.
llvm-svn: 189331
The initial port used MLG(R) for i64 UMUL_LOHI but left the other three
combinations as not-legal-or-custom. Although 32x32->{32,32}
multiplications exist, they're not as quick as doing a normal 64-bit
multiplication, so it didn't seem like i32 SMUL_LOHI and UMUL_LOHI
would be useful. There's also no direct instruction for i64 SMUL_LOHI,
so it needs to be implemented in terms of UMUL_LOHI.
However, not defining these patterns means that we don't convert
division by a constant into multiplication, so this patch fills
in the other cases. The new i64 SMUL_LOHI sequence is simpler
than the one that we used previously for 64x64->128 multiplication,
so int-mul-08.ll now tests the full sequence.
llvm-svn: 188898
This first cut is pretty conservative. The final argument register (R6)
is call-saved, so we would need to make sure that the R6 argument to a
sibling call is the same as the R6 argument to the calling function,
which seems worth keeping as a separate patch.
Saying that integer truncations are free means that we no longer
use the extending instructions LGF and LLGF for spills in int-conv-09.ll
and int-conv-10.ll. Instead we treat the registers as 64 bits wide and
truncate them to 32-bits where necessary. I think it's unlikely we'd
use LGF and LLGF for spills in other situations for the same reason,
so I'm removing the tests rather than replacing them. The associated
code is generic and applies to many more instructions than just
LGF and LLGF, so there is no corresponding code removal.
llvm-svn: 188669
