On Power10, it's profitable to schedule some stores with adjacent target
address together. This patch implements this feature.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D86754
This patch introduces two intrinsics: llvm.ppc.setflm and
llvm.ppc.readflm. They read from or write to FPSCR register
(floating-point status & control) which contains rounding mode and
exception status.
To ensure correctness of program, we need to prevent FP operations from
being moved across these intrinsics (mffs/mtfsf instruction), so here I
set them as scheduling boundaries. We can relax such restriction if
FPSCR is modeled well in the future.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D84914
In fixupIsDeadOrKill, we assume StartMI and EndMI not exist in same
basic block, so we add an assertion in that function. This is wrong
before RA, as before RA the true definition may exist in another
block through copy like instructions.
Reviewed By: nemanjai
Differential Revision: https://reviews.llvm.org/D83365
This patch tries to reassociate two patterns related to FMA to expose
more ILP on PowerPC.
// Pattern 1:
// A = FADD X, Y (Leaf)
// B = FMA A, M21, M22 (Prev)
// C = FMA B, M31, M32 (Root)
// -->
// A = FMA X, M21, M22
// B = FMA Y, M31, M32
// C = FADD A, B
// Pattern 2:
// A = FMA X, M11, M12 (Leaf)
// B = FMA A, M21, M22 (Prev)
// C = FMA B, M31, M32 (Root)
// -->
// A = FMUL M11, M12
// B = FMA X, M21, M22
// D = FMA A, M31, M32
// C = FADD B, D
Reviewed By: jsji
Differential Revision: https://reviews.llvm.org/D80175
This is a NFC patch to make convertToImmediateForm a light wrapper
for converting xform and imm form instructions on PowerPC.
Reviewed By: Steven.zhang
Differential Revision: https://reviews.llvm.org/D80907
This patch folds redundant load immediates into a zero for instructions
which recognise this as the value zero and not the register. If the load
immediate is no longer in use it is then deleted.
This is already done in earlier passes but the ppc-mi-peephole allows for
a more general implementation.
Differential Revision: https://reviews.llvm.org/D69168
Summary:
They all match the base implementation in
TargetInstrInfo::isUnpredicatedTerminator.
Follow up to D62749.
Reviewers: echristo, MaskRay, hfinkel
Reviewed By: echristo
Subscribers: wuzish, nemanjai, hiraditya, kbarton, llvm-commits, srhines
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D78976
Currently, on PowerPC target, it uses function scope UnsafeFPMath
option to drive Machine Combiner pass.
This is not accurate in two ways:
1: the scope is not accurate. Machine Combiner pass only requires
instruction-level flags instead of the function scope.
2: the float point flag is not accurate. Machine Combiner pass
only requires float point flags reassoc and nsz.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D78183
On little endian targets prior to Power9, we spill vector registers using a
swapping store (i.e. stdxvd2x saves the vector with the two doublewords in
big endian order regardless of endianness). This is generally not a problem
since we restore them using the corresponding swapping load (lxvd2x). However
if the restore is done by the unwinder, the vector register contains data in
the incorrect order.
This patch fixes that by using Altivec loads/stores for vector saves and
restores in PEI (which keep the order correct) under those specific conditions:
- EH aware function
- Subtarget requires swaps for VSX memops (Little Endian prior to Power9)
Differential revision: https://reviews.llvm.org/D73692
A known limitation for Future CPU is that the new prefixed instructions may
not cross 64 Byte boundaries.
All instructions are already 4 byte aligned so the only situation where this
can occur is when the prefix is in one 64 byte block and the instruction that
is prefixed is at the top of the next 64 byte block. To fix this case
PPCELFStreamer was added to intercept EmitInstruction. When a prefixed
instruction is emitted we try to align it to 64 Bytes by adding a maximum of
4 bytes. If the prefixed instruction crosses the 64 Byte boundary then the
alignment would trigger and a 4 byte nop would be added to push the
instruction into the next 64 byte block.
Differential Revision: https://reviews.llvm.org/D72570
Future CPU will include support for prefixed instructions.
These prefixed instructions are formed by a 4 byte prefix
immediately followed by a 4 byte instruction effectively
making an 8 byte instruction. The new instruction paddi
is a prefixed form of addi.
This patch adds paddi and all of the support required
for that instruction. The majority of the patch deals with
supporting the new prefixed instructions. The addition of
paddi is mainly to allow for testing.
Differential Revision: https://reviews.llvm.org/D72569
In GlobalISel we may in some unfortunate circumstances generate PHIs with
operands that are on separate banks. If-conversion doesn't currently check for
that case and ends up generating a CSEL on AArch64 with incorrect register
operands.
Differential Revision: https://reviews.llvm.org/D72961
We removed UseVSXReg flag in https://reviews.llvm.org/D58685
But we did not reclain the bit 6 it was assigned,
this will become confusing and a hole later..
We should reclaim it as early as possible before new bits.
Reviewed By: sfertile
Differential Revision: https://reviews.llvm.org/D72649
PowerPC uses a dedicated method to check if the machine instr is
predicable by opcode. However, there's a bit `isPredicable` in instr
definition. This patch removes the method and set the bit only to
opcodes referenced in it.
Differential Revision: https://reviews.llvm.org/D71921
MachineInstr.h included AliasAnalysis.h, which includes a world of IR
constructs mostly unneeded in CodeGen. Prune it. Same for
DebugInfoMetadata.h.
Noticed with -ftime-trace.
llvm-svn: 375311
Neither the base implementation of findCommutedOpIndices nor any in-tree target modifies the instruction passed in and there is no reason why they would in the future.
Committed on behalf of @hvdijk (Harald van Dijk)
Differential Revision: https://reviews.llvm.org/D66138
llvm-svn: 372882
Recommit: fix asan errors.
The way MachinePipeliner uses these target hooks is stateful - we reduce trip
count by one per call to reduceLoopCount. It's a little overfit for hardware
loops, where we don't have to worry about stitching a loop induction variable
across prologs and epilogs (the induction variable is implicit).
This patch introduces a new API:
/// Analyze loop L, which must be a single-basic-block loop, and if the
/// conditions can be understood enough produce a PipelinerLoopInfo object.
virtual std::unique_ptr<PipelinerLoopInfo>
analyzeLoopForPipelining(MachineBasicBlock *LoopBB) const;
The return value is expected to be an implementation of the abstract class:
/// Object returned by analyzeLoopForPipelining. Allows software pipelining
/// implementations to query attributes of the loop being pipelined.
class PipelinerLoopInfo {
public:
virtual ~PipelinerLoopInfo();
/// Return true if the given instruction should not be pipelined and should
/// be ignored. An example could be a loop comparison, or induction variable
/// update with no users being pipelined.
virtual bool shouldIgnoreForPipelining(const MachineInstr *MI) const = 0;
/// Create a condition to determine if the trip count of the loop is greater
/// than TC.
///
/// If the trip count is statically known to be greater than TC, return
/// true. If the trip count is statically known to be not greater than TC,
/// return false. Otherwise return nullopt and fill out Cond with the test
/// condition.
virtual Optional<bool>
createTripCountGreaterCondition(int TC, MachineBasicBlock &MBB,
SmallVectorImpl<MachineOperand> &Cond) = 0;
/// Modify the loop such that the trip count is
/// OriginalTC + TripCountAdjust.
virtual void adjustTripCount(int TripCountAdjust) = 0;
/// Called when the loop's preheader has been modified to NewPreheader.
virtual void setPreheader(MachineBasicBlock *NewPreheader) = 0;
/// Called when the loop is being removed.
virtual void disposed() = 0;
};
The Pipeliner (ModuloSchedule.cpp) can use this object to modify the loop while
allowing the target to hold its own state across all calls. This API, in
particular the disjunction of creating a trip count check condition and
adjusting the loop, improves the code quality in ModuloSchedule.cpp.
llvm-svn: 372463
The way MachinePipeliner uses these target hooks is stateful - we reduce trip
count by one per call to reduceLoopCount. It's a little overfit for hardware
loops, where we don't have to worry about stitching a loop induction variable
across prologs and epilogs (the induction variable is implicit).
This patch introduces a new API:
/// Analyze loop L, which must be a single-basic-block loop, and if the
/// conditions can be understood enough produce a PipelinerLoopInfo object.
virtual std::unique_ptr<PipelinerLoopInfo>
analyzeLoopForPipelining(MachineBasicBlock *LoopBB) const;
The return value is expected to be an implementation of the abstract class:
/// Object returned by analyzeLoopForPipelining. Allows software pipelining
/// implementations to query attributes of the loop being pipelined.
class PipelinerLoopInfo {
public:
virtual ~PipelinerLoopInfo();
/// Return true if the given instruction should not be pipelined and should
/// be ignored. An example could be a loop comparison, or induction variable
/// update with no users being pipelined.
virtual bool shouldIgnoreForPipelining(const MachineInstr *MI) const = 0;
/// Create a condition to determine if the trip count of the loop is greater
/// than TC.
///
/// If the trip count is statically known to be greater than TC, return
/// true. If the trip count is statically known to be not greater than TC,
/// return false. Otherwise return nullopt and fill out Cond with the test
/// condition.
virtual Optional<bool>
createTripCountGreaterCondition(int TC, MachineBasicBlock &MBB,
SmallVectorImpl<MachineOperand> &Cond) = 0;
/// Modify the loop such that the trip count is
/// OriginalTC + TripCountAdjust.
virtual void adjustTripCount(int TripCountAdjust) = 0;
/// Called when the loop's preheader has been modified to NewPreheader.
virtual void setPreheader(MachineBasicBlock *NewPreheader) = 0;
/// Called when the loop is being removed.
virtual void disposed() = 0;
};
The Pipeliner (ModuloSchedule.cpp) can use this object to modify the loop while
allowing the target to hold its own state across all calls. This API, in
particular the disjunction of creating a trip count check condition and
adjusting the loop, improves the code quality in ModuloSchedule.cpp.
llvm-svn: 372376
Summary:
In PostRA phase, we often have to find out the most recent definition
of a register. This patch adds getDefMIPostRA so that other methods
can use it rather than implementing it repeatedly.
Differential Revision: https://reviews.llvm.org/D65131
llvm-svn: 366990
After implemented this hook, we will model the memory dependency in the scheduling dependency graph more precise,
and will have more opportunity to reorder the load/stores, as they didn't have the dependency at some condition
Differential Revision: https://reviews.llvm.org/D63804
llvm-svn: 364886
Implement necessary target hooks to enable MachinePipeliner for P9 only.
The pass is off by default, can be enabled with -ppc-enable-pipeliner for P9.
Differential Revision: https://reviews.llvm.org/D62164
llvm-svn: 363085
The UseVSXReg flag can be safely removed and the code cleaned up.
Patch By: Yi-Hong Liu
Differential Revision: https://reviews.llvm.org/D58685
llvm-svn: 357028
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
If we are changing the MI operand from Reg to Imm, we need also handle its implicit use if have.
Differential Revision: https://reviews.llvm.org/D56078
llvm-svn: 350115
The D-Form VSX loads introduced in ISA 3.0 are not direct D-Form equivalent of
the corresponding X-Forms since they only target the Altivec registers.
Namely LXSSPX can load into any of the 64 VSX registers whereas LXSSP can only
load into the upper 32 VSX registers. Similarly with the remaining affected
instructions.
There is currently no way that I can see to trigger the bug, but as we add other
ways of exploiting these instructions, there may very well be instances that do.
This is an NFC patch in practical terms since the changes it introduces can not
be triggered without an MIR test.
Differential revision: https://reviews.llvm.org/D53323
llvm-svn: 344894
There are occasionally instances where AADB rewrites registers in such a way
that a reg-reg copy becomes a self-copy. Such an instruction is obviously
redundant and can be removed. This patch does precisely that.
Note that this will not remove various nop's that we insert (which are
themselves just self-copies). The reason those are left alone is that all of
them have their own opcodes (that just encode to a self-copy).
What prompted this patch is the fact that these self-copies sometimes end up
using registers that make the instruction a priority-setting nop, thereby
having a significant effect on performance.
Differential revision: https://reviews.llvm.org/D52432
llvm-svn: 344036
We have an unfortunate situation in our back end where we have to keep pairs of
functions synchronized. Needless to say that this is not an ideal situation as
it is very difficult to enforce. Even without bugs, it's annoying to have to do
the same thing in two places.
This patch just refactors the code so that the two pairs of those functions that
pertain to printing register operands are unified:
- stripRegisterPrefix() - this just removes the letter prefixes from registers
for the InstrPrinter and AsmPrinter. This patch provides this as a static
member of PPCRegisterInfo
- Handling of PPCII::UseVSXReg - there are 3 places where we do something
special for instructions with that flag set. Each of those places does its
own checking of this flag and implements code customization. Any changes to
how we print/encode VSX/VMX registers require modifying all 3 places. This
patch unifies this into a static function in PPCInstrInfo that returns the
register number adjusted as needed.
Differential revision: https://reviews.llvm.org/D52467
llvm-svn: 343195
If the arch is P8, we will select XFLOAD to load the floating point, and then, expand it to vsx and non-vsx X-form instruction post RA. This patch is trying to convert the X-form to D-form if it meets the requirement that one operand of the x-form inst is the special Zero register, and another operand fed by add inst. i.e.
y = add imm, reg
LFDX. 0, y
-->
LFD imm(reg)
Reviewers: Nemanjai
Differential Revision: https://reviews.llvm.org/D49007
llvm-svn: 340149
A new function getOpcodeForSpill should now be the only place to get
the opcode for a given spilled register.
Differential Revision: https://reviews.llvm.org/D43086
llvm-svn: 328556
David Blaikie