Summary:
When the branch folder hoist code into a predecessor it adjust live-in's
in the blocks it hoist code from. However it fail to handle hoisted code
that contain a defed register that originally is live-in in the block
through a super register.
This is fixed by replacing the live-in handling code with calls to
utility functions in LivePhysRegs.
Reviewers: kparzysz, gberry, MatzeB, uweigand, aprantl
Reviewed By: kparzysz
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D47529
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@334163 91177308-0d34-0410-b5e6-96231b3b80d8
Remember to check if store is truncating before calling
combineTruncateExtract().
Review: Ulrich Weigand
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@333262 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, this pass would look at the (static) set returned by
getCallPreservedMask() and add those back as preserved in the case when
isSafeForNoCSROpt() returns false.
A problem is that a target may have to save some registers even when NoCSROpt
takes place. For instance, on SystemZ, the return register is needed upon
return from a function.
Furthermore, getCallPreservedMask() only includes the registers that the
target actually wishes to emit save/restore instructions for. This means that
subregs and (fully saved) superregs are missing.
This patch instead takes the (dynamic) set returned by target for the
function from determineCalleeSaves() and then adds sub/super regs to build
the set to be used when building the RegMask for the function.
Review: Quentin Colombet, Ulrich Weigand
https://reviews.llvm.org/D46315
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@333261 91177308-0d34-0410-b5e6-96231b3b80d8
MVCLoop clobbers CC (since it emits a compare/branch), but this was not
modelled.
Review: Ulrich Weigand
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331627 91177308-0d34-0410-b5e6-96231b3b80d8
Don't assume the alias of a defined reg is always already in the set.
As the test case in https://bugs.llvm.org/show_bug.cgi?id=36587 discovered,
it is wrong to assume that all the aliases of the defined register in the
*current function* is already present in the UsedPhysRegsMask.
This patch changes this so that any definition in the current function of a
phys-reg always results in all its aliases inserted into the set of defined
registers.
Review: Quentin Colombet
https://reviews.llvm.org/D45157
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331509 91177308-0d34-0410-b5e6-96231b3b80d8
This provides an optimized implementation of SADDO/SSUBO/UADDO/USUBO
as well as ADDCARRY/SUBCARRY on top of the new CC implementation.
In particular, multi-word arithmetic now uses UADDO/ADDCARRY instead
of the old ADDC/ADDE logic, which means we no longer need to use
"glue" links for those instructions. This also allows making full
use of the memory-based instructions like ALSI, which couldn't be
recognized due to limitations in the DAG matcher previously.
Also, the llvm.sadd.with.overflow et.al. intrinsincs now expand to
directly using the ADD instructions and checking for a CC 3 result.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331203 91177308-0d34-0410-b5e6-96231b3b80d8
Currently, an instruction setting the condition code is linked to
the instruction using the condition code via a "glue" link in the
SelectionDAG. This has a number of drawbacks; in particular, it
means the same CC cannot be used by multiple users. It also makes
it more difficult to efficiently implement SADDO et. al.
This patch changes the back-end to represent CC dependencies as
normal values during SelectionDAG matching, along the lines of
how this is handled in the X86 back-end already.
In addition to the core mechanics of updating all relevant patterns,
this requires a number of additional changes:
- We now need to be able to spill/restore a CC value into a GPR
if necessary. This means providing a copyPhysReg implementation
for moves involving CC, and defining getCrossCopyRegClass.
- Since we still prefer to avoid such spills, we provide an override
for IsProfitableToFold to avoid creating a merged LOAD / ICMP if
this would result in multiple users of the CC.
- combineCCMask no longer requires a single CC user, and no longer
need to be careful about preventing invalid glue/chain cycles.
- emitSelect needs to be more careful in marking CC live-in to
the basic block it generates. Also, we can now optimize the
case of multiple subsequent selects with the same condition
just like X86 does.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331202 91177308-0d34-0410-b5e6-96231b3b80d8
If we have LOCR instructions, select them directly from SelectionDAG
instead of first going through a pseudo instruction and then using
the custom inserter to emit the LOCR.
Provide Select pseudo-instructions for VR32/VR64 if we have vector
instructions, to avoid having to go through the first 16 FPRs
unnecessarily.
If we do not have LOCFHR, prefer using LOCR followed by a move
over a conditional branch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331191 91177308-0d34-0410-b5e6-96231b3b80d8
This patch fixes an issue exposed on the SystemZ build bots when committing
https://reviews.llvm.org/rL327856. The hoisting was temporarily disabled with
an option. This patch now re-enables hoisting and checks that we only hoist a
store instruction when all its operands are either constant caller preserved
registers or immediates.
Differential Revision: https://reviews.llvm.org/D45286
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@329577 91177308-0d34-0410-b5e6-96231b3b80d8
If DoneMBB becomes empty it must have CC added to its live-in list, since it
will fall-through into EndMBB. This happens when the CLC loop does the
complete range.
Review: Ulrich Weigand
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@327834 91177308-0d34-0410-b5e6-96231b3b80d8
Improve/implement these methods to improve DAG combining. This mainly
concerns intrinsics.
Some constant operands to SystemZISD nodes have been marked Opaque to avoid
transforming back and forth between generic and target nodes infinitely.
Review: Ulrich Weigand
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@327765 91177308-0d34-0410-b5e6-96231b3b80d8
The BITCAST handling in computeKnownBits() previously only worked for little
endian.
This patch reverses the iteration over elements for a big endian target which
allows this to work in this case also.
SystemZ test case.
Review: Eli Friedman
https://reviews.llvm.org/D44249
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@327764 91177308-0d34-0410-b5e6-96231b3b80d8
splitMergedValStore will split a store into two if target prefers this, or if
-force-split-store is passed.
This patch adds the missing handling for endianness in this function along
with a test case.
Review: Eli Friedman
https://reviews.llvm.org/D44396
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@327375 91177308-0d34-0410-b5e6-96231b3b80d8
This adds back-end support for the anyregcc calling convention
for use with patchpoints.
Since all registers are considered call-saved with anyregcc
(except for 0 and 1 which may still be clobbered by PLT stubs
and the like), this required adding support for saving and
restoring vector registers in prologue/epilogue code for the
first time. This is not used by any other calling convention.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326612 91177308-0d34-0410-b5e6-96231b3b80d8
This adds back-end support for the @llvm.experimental.stackmap and
@llvm.experimental.patchpoint intrinsics.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326611 91177308-0d34-0410-b5e6-96231b3b80d8
On SystemZ we need to provide a register save area of 160 bytes to
any called function. This size needs to be added when allocating
stack in the function prologue. However, it was not accounted for
as part of MachineFrameInfo::getStackSize(); instead the back-end
used a private routine getAllocatedStackSize().
This is OK for code-gen purposes, but it breaks other users of
the getStackSize() routine, in particular it breaks the recently-
added -stack-size-section feature.
Fix this by updating the main stack size tracked by common code
(in emitPrologue) instead of using the private routine.
No change in code generation intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326610 91177308-0d34-0410-b5e6-96231b3b80d8
This adds support for specifying vector registers for use with inline
asm statements, either via the 'v' constraint or by explicit register
names (v0 ... v31).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326609 91177308-0d34-0410-b5e6-96231b3b80d8
Re-enable commit r323991 now that r325931 has been committed to make
MachineOperand::isRenamable() check more conservative w.r.t. code
changes and opt-in on a per-target basis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326208 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r323991.
This commit breaks target that don't model all the register constraints
in TableGen. So far the workaround was to set the
hasExtraXXXRegAllocReq, but it proves that it doesn't cover all the
cases.
For instance, when mutating an instruction (like in the lowering of
COPYs) the isRenamable flag is not properly updated. The same problem
will happen when attaching machine operand from one instruction to
another.
Geoff Berry is working on a fix in https://reviews.llvm.org/D43042.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@325421 91177308-0d34-0410-b5e6-96231b3b80d8
When handling vectors with non byte-sized elements, reverse the order of the
elements in the built integer if the target is Big-Endian.
SystemZ tests updated.
Review: Eli Friedman, Ulrich Weigand.
https://reviews.llvm.org/D42786
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@324063 91177308-0d34-0410-b5e6-96231b3b80d8
test/CodeGen/SystemZ/vec-trunc-to-i1.ll was marked as a temporary
FAIL when it was previously updated when it needed one more COPY.
This was however wrong, since the loop body had been reduced
significantly, and it was actually an improvement.
Review: Ulrich Weigand.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@324060 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This change extends MachineCopyPropagation to do COPY source forwarding
and adds an additional run of the pass to the default pass pipeline just
after register allocation.
This version of this patch uses the newly added
MachineOperand::isRenamable bit to avoid forwarding registers is such a
way as to violate constraints that aren't captured in the
Machine IR (e.g. ABI or ISA constraints).
This change is a continuation of the work started in D30751.
Reviewers: qcolombet, javed.absar, MatzeB, jonpa, tstellar
Subscribers: tpr, mgorny, mcrosier, nhaehnle, nemanjai, jyknight, hfinkel, arsenm, inouehrs, eraman, sdardis, guyblank, fedor.sergeev, aheejin, dschuff, jfb, myatsina, llvm-commits
Differential Revision: https://reviews.llvm.org/D41835
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@323991 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
In Instruction Selection UpdateChains replaces all matched Nodes'
chain references including interior token factors and deletes them.
This may allow nodes which depend on these interior nodes but are not
part of the set of matched nodes to be left with a dangling dependence.
Avoid this by doing the replacement for matched non-TokenFactor nodes.
Fixes PR36164.
Reviewers: jonpa, RKSimon, bogner
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D42754
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@323977 91177308-0d34-0410-b5e6-96231b3b80d8
Since these methods will assert if the integer does not fit into 64 bits,
it is necessary to do this check before calling them in
supportedAddressingMode().
Review: Ulrich Weigand.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@323866 91177308-0d34-0410-b5e6-96231b3b80d8
On current machines we have load-on-condition instructions that can be
used to directly implement the SETCC semantics. If we have those, it is
always preferable to use them instead of generating the IPM sequence.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322989 91177308-0d34-0410-b5e6-96231b3b80d8
In order to implement a test whether a compare-and-swap succeeded, the
SystemZ back-end currently emits a rather inefficient sequence of first
converting the CC result into an integer, and then testing that integer
against zero. This commit changes the back-end to simply directly test
the CC value set by the compare-and-swap instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322988 91177308-0d34-0410-b5e6-96231b3b80d8
The SystemZ back-end uses a sequence of IPM followed by arithmetic
operations to implement the SETCC primitive. This is currently done
early during SelectionDAG. This patch moves generating those sequences
to much later in SelectionDAG (during PreprocessISelDAG).
This doesn't change much in generated code by itself, but it allows
further enhancements that will be checked-in as follow-on commits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322987 91177308-0d34-0410-b5e6-96231b3b80d8
BRCTH is capable of a long branch which needs to be recognized during branch
relaxation. This is done by checking for ExtraRelaxSize == 0.
Review: Ulrich Weigand
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322688 91177308-0d34-0410-b5e6-96231b3b80d8
Prefetches used to always be chained between any previous and following
memory accesses. The problem with this was that later optimizations, such as
folding of a load into the user instruction, got disrupted.
This patch relaxes the chaining of prefetches in order to remedy this.
Reveiw: Hal Finkel
https://reviews.llvm.org/D38886
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322163 91177308-0d34-0410-b5e6-96231b3b80d8
Planning to add support for named vregs. This puts is in a conundrum since
physregs are named as well. To rectify this we need to use a sigil other than
'%' for physregs in MIR. We've settled on using '$' for physregs but first we
must repurpose it from external symbols using it, which is what this commit is
all about. We think '&' will have familiar semantics for C/C++ users.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322146 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Add isRenamable() predicate to MachineOperand. This predicate can be
used by machine passes after register allocation to determine whether it
is safe to rename a given register operand. Register operands that
aren't marked as renamable may be required to be assigned their current
register to satisfy constraints that are not captured by the machine
IR (e.g. ABI or ISA constraints).
Reviewers: qcolombet, MatzeB, hfinkel
Subscribers: nemanjai, mcrosier, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D39400
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320503 91177308-0d34-0410-b5e6-96231b3b80d8
Csmith discovered a program that caused wrong code generation with -O0:
When handling a SIGN_EXTEND in expandRxSBG(), RxSBG.BitSize may be less than
the Input width (if a truncate was previously traversed), so maskMatters()
should be called with a masked based on the width of the sign extend result
instead.
Review: Ulrich Weigand
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319892 91177308-0d34-0410-b5e6-96231b3b80d8
