Several integer multiply/divide instructions require use of a
register pair as input and output. This patch moves setting
up the input register pair from C++ code to TableGen, simplifying
the whole process and making it more easily extensible.
No functional change.
llvm-svn: 307155
Csmith discovered that this function can be called with a zero argument,
in which case an assert for this triggered.
This patch also adds a guard before the other call to this function since
it was missing, although the test only covers the case where it was
discovered.
Reduced test case attached as CodeGen/SystemZ/int-cmp-54.ll.
Review: Ulrich Weigand
llvm-svn: 306287
This reverts the use of TargetLowering::prepareVolatileOrAtomicLoad
introduced by r196905. Nothing in the semantics of the "volatile"
keyword or the definition of the z/Architecture actually requires
that volatile loads are preceded by a serialization operation, and
no other compiler on the platform actually implements this.
Since we've now seen a use case where this additional serialization
causes noticable performance degradation, this patch removes it.
The patch still leaves in the serialization before atomic loads,
which is now implemented directly in lowerATOMIC_LOAD. (This also
seems overkill, but that can be addressed separately.)
llvm-svn: 306117
Use VLREP when inserting one or more loads into a vector. This is more
efficient than to first load and then use a VLVGP.
Review: Ulrich Weigand
llvm-svn: 304152
This method must return a valid register class, or the list-ilp isel
scheduler will crash. For MVT::Untyped nullptr was previously returned, but
now ADDR128BitRegClass is returned instead. This is needed just as long as
list-ilp (and probably also list-hybrid) is still there.
Review: Ulrich Weigand, A Trick
https://reviews.llvm.org/D32802
llvm-svn: 302649
Using arguments with attribute inalloca creates problems for verification
of machine representation. This attribute instructs the backend that the
argument is prepared in stack prior to CALLSEQ_START..CALLSEQ_END
sequence (see http://llvm.org/docs/InAlloca.htm for details). Frame size
stored in CALLSEQ_START in this case does not count the size of this
argument. However CALLSEQ_END still keeps total frame size, as caller can
be responsible for cleanup of entire frame. So CALLSEQ_START and
CALLSEQ_END keep different frame size and the difference is treated by
MachineVerifier as stack error. Currently there is no way to distinguish
this case from actual errors.
This patch adds additional argument to CALLSEQ_START and its
target-specific counterparts to keep size of stack that is set up prior to
the call frame sequence. This argument allows MachineVerifier to calculate
actual frame size associated with frame setup instruction and correctly
process the case of inalloca arguments.
The changes made by the patch are:
- Frame setup instructions get the second mandatory argument. It
affects all targets that use frame pseudo instructions and touched many
files although the changes are uniform.
- Access to frame properties are implemented using special instructions
rather than calls getOperand(N).getImm(). For X86 and ARM such
replacement was made previously.
- Changes that reflect appearance of additional argument of frame setup
instruction. These involve proper instruction initialization and
methods that access instruction arguments.
- MachineVerifier retrieves frame size using method, which reports sum of
frame parts initialized inside frame instruction pair and outside it.
The patch implements approach proposed by Quentin Colombet in
https://bugs.llvm.org/show_bug.cgi?id=27481#c1.
It fixes 9 tests failed with machine verifier enabled and listed
in PR27481.
Differential Revision: https://reviews.llvm.org/D32394
llvm-svn: 302527
This patch replaces the separate APInts for KnownZero/KnownOne with a single KnownBits struct. This is similar to what was done to ValueTracking's version recently.
This is largely a mechanical transformation from KnownZero to Known.Zero.
Differential Revision: https://reviews.llvm.org/D32569
llvm-svn: 301620
getArithmeticInstrCost(), getShuffleCost(), getCastInstrCost(),
getCmpSelInstrCost(), getVectorInstrCost(), getMemoryOpCost(),
getInterleavedMemoryOpCost() implemented.
Interleaved access vectorization enabled.
BasicTTIImpl::getCastInstrCost() improved to check for legal extending loads,
in which case the cost of the z/sext instruction becomes 0.
Review: Ulrich Weigand, Renato Golin.
https://reviews.llvm.org/D29631
llvm-svn: 300052
A test case was found with llvm-stress that caused DAGCombiner to crash
when compiling for an older subtarget without vector support.
SystemZTargetLowering::combineTruncateExtract() should do nothing for older
subtargets.
This check was placed in canTreatAsByteVector(), which also helps in a few
other places.
Review: Ulrich Weigand
llvm-svn: 299763
Even on older subtargets that lack vector support, there may be vector values
with just one element in the input program. These are converted during DAG
legalization to scalar values.
The pre-legalize SystemZ DAGCombiner methods should in this circumstance not
touch these nodes. This patch adds a check for this in
SystemZTargetLowering::combineEXTRACT_VECTOR_ELT().
Review: Ulrich Weigand
llvm-svn: 299213
The GeneralShuffle::add() method used to have an assert that made sure that
source elements were at least as big as the destination elements. This was
wrong, since it is actually expected that an EXTRACT_VECTOR_ELT node with a
smaller source element type than the return type gets extended.
Therefore, instead of asserting this, it is just checked and if this is the
case 'false' is returned from the GeneralShuffle::add() method. This case
should be very rare and is not handled further by the backend.
Review: Ulrich Weigand.
llvm-svn: 292888
Rename from addOperand to just add, to match the other method that has been
added to MachineInstrBuilder for adding more than just 1 operand.
See https://reviews.llvm.org/D28057 for the whole discussion.
Differential Revision: https://reviews.llvm.org/D28556
llvm-svn: 291891
A store of an extracted element or a load which gets inserted into a vector,
will be combined into a vector load/store element instruction.
Therefore, isFoldableMemAccessOffset(), which is called by LSR, should
return false in these cases.
Reviewer: Ulrich Weigand
llvm-svn: 291673
This patch moves formation of LOC-type instructions from (late)
IfConversion to the early if-conversion pass, and in some cases
additionally creates them directly from select instructions
during DAG instruction selection.
To make early if-conversion work, the patch implements the
canInsertSelect / insertSelect callbacks. It also implements
the commuteInstructionImpl and FoldImmediate callbacks to
enable generation of the full range of LOC instructions.
Finally, the patch adds support for all instructions of the
load-store-on-condition-2 facility, which allows using LOC
instructions also for high registers.
Due to the use of the GRX32 register class to enable high registers,
we now also have to handle the cases where there are still no single
hardware instructions (conditional move from a low register to a high
register or vice versa). These are converted back to a branch sequence
after register allocation. Since the expandRAPseudos callback is not
allowed to create new basic blocks, this requires a simple new pass,
modelled after the ARM/AArch64 ExpandPseudos pass.
Overall, this patch causes significantly more LOC-type instructions
to be used, and results in a measurable performance improvement.
llvm-svn: 288028
Add the 16 access registers as LLVM registers. This allows removing
a lot of special cases in the assembler and disassembler where we
were handling access registers; this can all just use the generic
register code now.
Also add a bunch of instructions to operate on access registers,
for assembler/disassembler use only. No change in code generation
intended.
llvm-svn: 286283
The change in r279105 causes an infinite loop in some cases, as it sets the upper bits of an AND mask constant, which DAGCombiner::SimplifyDemandedBits then unsets.
This patch reverts that part of the behaviour, instead relying on .td peepholes to perform the transformation to NILL. I reapplied my original fix for the problem addressed by r279105 (unsetting the upper bits, which prevents a compiler abort for a different reason).
Differential Revision: https://reviews.llvm.org/D23781
llvm-svn: 279515
The names of the tablegen defs now match the names of the ISD nodes.
This makes the world a slightly saner place, as previously "fround" matched
ISD::FP_ROUND and not ISD::FROUND.
Differential Revision: https://reviews.llvm.org/D23597
llvm-svn: 279129
Normally, when an AND with a constant is lowered to NILL, the constant value is truncated to 16 bits. However, since r274066, ANDs whose results are used in a shift are caught by a different pattern that does not truncate. The instruction printer expects a 16-bit unsigned immediate operand for NILL, so this results in an abort.
This patch adds code to manually truncate the constant in this situation. The rest of the bits are then set, so we will detect a case for NILL "naturally" rather than using peephole optimizations.
Differential Revision: http://reviews.llvm.org/D21854
llvm-svn: 279105
Refactored so that a LSRUse owns its fixups, as oppsed to letting the
LSRInstance own them. This makes it easier to rate formulas for
LSRUses, since the fixups are available directly. The Offsets vector
has been removed since it was no longer necessary.
New target hook isFoldableMemAccessOffset(), which is used during formula
rating.
For SystemZ, this is useful to express that loads and stores with
float or vector types with a big/negative offset should be avoided in
loops. Without this, LSR will generate a lot of negative offsets that
would require extra instructions for loading the address.
Updated tests:
test/CodeGen/SystemZ/loop-01.ll
Reviewed by: Quentin Colombet and Ulrich Weigand.
https://reviews.llvm.org/D19152
llvm-svn: 278927
Summary:
Instead, we take a single flags arg (a bitset).
Also add a default 0 alignment, and change the order of arguments so the
alignment comes before the flags.
This greatly simplifies many callsites, and fixes a bug in
AMDGPUISelLowering, wherein the order of the args to getLoad was
inverted. It also greatly simplifies the process of adding another flag
to getLoad.
Reviewers: chandlerc, tstellarAMD
Subscribers: jholewinski, arsenm, jyknight, dsanders, nemanjai, llvm-commits
Differential Revision: http://reviews.llvm.org/D22249
llvm-svn: 275592
This adds a new SystemZ-specific intrinsic, llvm.s390.tdc.f(32|64|128),
which maps straight to the test data class instructions. A new IR pass
is added to recognize instructions that can be converted to TDC and
perform the necessary replacements.
Differential Revision: http://reviews.llvm.org/D21949
llvm-svn: 275016
On SystemZ, shift and rotate instructions only use the bottom 6 bits of the shift/rotate amount.
Therefore, if the amount is ANDed with an immediate mask that has all of the bottom 6 bits set, we
can remove the AND operation entirely.
Differential Revision: http://reviews.llvm.org/D21854
llvm-svn: 274650
This is a mechanical change to make TargetLowering API take MachineInstr&
(instead of MachineInstr*), since the argument is expected to be a valid
MachineInstr. In one case, changed a parameter from MachineInstr* to
MachineBasicBlock::iterator, since it was used as an insertion point.
As a side effect, this removes a bunch of MachineInstr* to
MachineBasicBlock::iterator implicit conversions, a necessary step
toward fixing PR26753.
llvm-svn: 274287
This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.
llvm-svn: 272512
Support and generate Compare and Traps like CRT, CIT, etc.
Support Trap as legal DAG opcodes and generate "j .+2" for them by default.
Add support for Conditional Traps and use the If Converter to convert them into
the corresponding compare and trap opcodes.
Differential Revision: http://reviews.llvm.org/D21155
llvm-svn: 272419
Summary: On Linux, /usr/include/bits/byteswap-16.h defines __byteswap_16(x) as an inlined LRVH (Load Reversed Half-word) instruction. The SystemZ back-end did not support this opcode and the inlined assembly would cause a fatal error.
Reviewers: bryanpkc, uweigand
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D18732
llvm-svn: 269688
This introduces a SystemZ-specific "backchain" attribute on function, which
enables writing the frame backchain link as specified by the ABI. This will
be used to implement -mbackchain option in clang.
Differential Revision: http://reviews.llvm.org/D19889
Fixed in this version: added RegState::Define and RegState::Kill on R1D
in prologue.
llvm-svn: 268581
This introduces a SystemZ-specific "backchain" attribute on function, which
enables writing the frame backchain link as specified by the ABI. This will
be used to implement -mbackchain option in clang.
Differential Revision: http://reviews.llvm.org/D19889
llvm-svn: 268571
Summary:
Port rL265480, rL264754, rL265997 and rL266252 to SystemZ, in order to enable the Swift port on the architecture. SwiftSelf and SwiftError are assigned to R10 and R9, respectively, which are normally callee-saved registers. For more information, see:
RFC: Implementing the Swift calling convention in LLVM and Clang
https://groups.google.com/forum/#!topic/llvm-dev/epDd2w93kZ0
Reviewers: kbarton, manmanren, rjmccall, uweigand
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D19414
llvm-svn: 267823
Summary:
In the context of http://wg21.link/lwg2445 C++ uses the concept of
'stronger' ordering but doesn't define it properly. This should be fixed
in C++17 barring a small question that's still open.
The code currently plays fast and loose with the AtomicOrdering
enum. Using an enum class is one step towards tightening things. I later
also want to tighten related enums, such as clang's
AtomicOrderingKind (which should be shared with LLVM as a 'C++ ABI'
enum).
This change touches a few lines of code which can be improved later, I'd
like to keep it as NFC for now as it's already quite complex. I have
related changes for clang.
As a follow-up I'll add:
bool operator<(AtomicOrdering, AtomicOrdering) = delete;
bool operator>(AtomicOrdering, AtomicOrdering) = delete;
bool operator<=(AtomicOrdering, AtomicOrdering) = delete;
bool operator>=(AtomicOrdering, AtomicOrdering) = delete;
This is separate so that clang and LLVM changes don't need to be in sync.
Reviewers: jyknight, reames
Subscribers: jyknight, llvm-commits
Differential Revision: http://reviews.llvm.org/D18775
llvm-svn: 265602
Ulrich Weigand