Enable multiple COPY hints to eliminate more COPYs during register allocation.
Note that this is something all targets should do, see
https://reviews.llvm.org/D38128.
Review: James Y Knight
llvm-svn: 326028
V_SUBBREV_U32 is a commute opcode for V_SUBB_U32. However, when
we try to commute V_SUBB_U32 in order to shrink it we do not then
process V_SUBBREV_U32 and it stay VOP3. This is fixed.
Differential Revision: https://reviews.llvm.org/D43699
llvm-svn: 326011
This portion can be matched by other patterns. We don't need it to make the larger pattern valid. It's sufficient to have a v1i1 mask input without caring where it came from.
llvm-svn: 325999
This pass performs peephole optimizations to cleanup ugly code sequences at
MachineInstruction layer.
Currently, the only optimization in this pass is to eliminate type
promotion
sequences for zero extending 32-bit subregisters to 64-bit registers.
If the compiler could prove the zero extended source come from 32-bit
subregistere then it is safe to erase those promotion sequece, because the
upper half of the underlying 64-bit registers were zeroed implicitly
already.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325991
When -mattr=+alu32 passed to the disassembler, use decoder namespace for
32-bit subregister.
This is to disassemble load and store instructions in preferred B format
as described in previous commit:
w = *(u8 *) (r + off) // BPF_LDX | BPF_B
w = *(u16 *)(r + off) // BPF_LDX | BPF_H
w = *(u32 *)(r + off) // BPF_LDX | BPF_W
*(u8 *) (r + off) = w // BPF_STX | BPF_B
*(u16 *)(r + off) = w // BPF_STX | BPF_H
*(u32 *)(r + off) = w // BPF_STX | BPF_W
NOTE: all other instructions should still use the default decoder
namespace.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325990
After all those preparation patches, now we could enable 32-bit subregister
support once -mattr=+alu32 specified.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325989
This patch support 32-bit subregister in three InstrInfo hooks, i.e.
copyPhysReg, loadRegFromStackSlot and storeRegToStackSlot,
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325988
The instruction mapping between eBPF/arm64/x86_64 are:
eBPF arm64 x86_64
LD1 BPF_LDX | BPF_B ldrb movzbl
LD2 BPF_LDX | BPF_H ldrh movzwl
LD4 BPF_LDX | BPF_W ldr movl
movzbl/movzwl/movl on x86_64 accept 32-bit sub-register, for example %eax,
the same for ldrb/ldrh on arm64 which accept 32-bit "w" register. And
actually these instructions only accept sub-registers. There is no point
to have LD1/2/4 (unsigned) for 64-bit register, because on these arches,
upper 32-bits are guaranteed to be zeroed by hardware or VM, so load into
the smallest available register class is the best choice for maintaining
type information.
For eBPF we should adopt the same philosophy, to change current
format (A):
r = *(u8 *) (r + off) // BPF_LDX | BPF_B
r = *(u16 *)(r + off) // BPF_LDX | BPF_H
r = *(u32 *)(r + off) // BPF_LDX | BPF_W
*(u8 *) (r + off) = r // BPF_STX | BPF_B
*(u16 *)(r + off) = r // BPF_STX | BPF_H
*(u32 *)(r + off) = r // BPF_STX | BPF_W
into B:
w = *(u8 *) (r + off) // BPF_LDX | BPF_B
w = *(u16 *)(r + off) // BPF_LDX | BPF_H
w = *(u32 *)(r + off) // BPF_LDX | BPF_W
*(u8 *) (r + off) = w // BPF_STX | BPF_B
*(u16 *)(r + off) = w // BPF_STX | BPF_H
*(u32 *)(r + off) = w // BPF_STX | BPF_W
There is no change on encoding nor how should they be interpreted,
everything is as it is, load the specified length, write into low bits of
the register then zeroing all remaining high bits.
The only change is their associated register class and how compiler view
them.
Format A still need to be kept, because eBPF LLVM backend doesn't support
sub-registers at default, but once 32-bit subregister is enabled, it should
use format B.
This patch implemented this together with all those necessary extended load
and truncated store patterns.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325987
getScalarShiftAmount method should be implemented for eBPF backend to make
sure shift amount could still get correct type once 32-bit subregisters
support are enabled.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325986
We need to support condition comparison on i32. All these comparisons are
supposed to be combined into BPF_J* instructions which only support i64.
For ISD::BR_CC we need to promote it to i64 first, then do custom lowering.
For ISD::SET_CC, just expand to SELECT_CC like what's been done for i64.
For ISD::SELECT_CC, we also want to do custom lower for i32. However, after
32-bit subregister support enabled, it is possible the comparison operands
are i32 while the selected value are i64, or the comparison operands are
i64 while the selected value are i32. We need to define extra instruction
pattern and support them in custom instruction inserter.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325985
There is no eBPF ISA support for BSWAP, ROTR, ROTL, SREM, SDIVREM, MULHU,
ADDC, ADDE etc on i32.
They could be emulated by other basic BPF_ALU operations, we'd set their
lowering action the same as i64.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325984
This patch add new calling conventions to allow GPR32RegClass as valid
register class for arguments and return types.
New calling convention will only be choosen when -mattr=+alu32 specified.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325983
This new attribute aims to control the enablement of 32-bit subregister
support on eBPF backend.
Name the interface as "alu32" is because we in particular want to enable
the generation of BPF_ALU32 instructions by enable subregister support.
This attribute could be used in the following format with llc:
llc -mtriple=bpf -mattr=[+|-]alu32
It is disabled at default.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325982
For transformations between i32 and i64, if it is explicit signed extension:
- first cast the operand to i64
- then use SLL + SRA to finish the extension.
if it is explicit zero extension:
- first cast the operand to i64
- then use SLL + SRL to finish the extension.
if it is explicit any extension:
- just refer to 64-bit register.
if it is explicit truncation:
- just refer to 32-bit subregister.
NOTE: Some of the zero extension sequences might be unnecessary, they will be
removed by an peephole pass on MachineInstruction layer.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325981
These 32-bit ALU insn patterns which takes immediate as one operand were
initially added to enable AsmParser support, and the AsmMatcher uses "ins"
and "outs" fields to deduct the operand constraint.
However, the instruction selector doesn't work the same as AsmMatcher. The
selector will use the "pattern" field for which we are not setting the
predication for immediate operands correctly.
Without this patch, i32 would eventually means all i32 operands are valid,
both imm and gpr, while these patterns should allow imm only.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325980
markSuperRegs is the canonical helper function used to mark reserved
registers. It could mark any overlapping sub-registers automatically.
Reviewed-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
llvm-svn: 325979
The instruction sequence used to get the address of the PC into a GPR requires
that we clobber the link register. Doing so without having first saved it in
the prologue leaves the function unable to return. Currently, this sequence is
emitted into the entry block. To ensure the prologue is inserted before this
sequence, disable shrink-wrapping.
This fixes PR33547.
Differential Revision: https://reviews.llvm.org/D43677
llvm-svn: 325972
This has the advantage of making release only builds more warning
free and there's no need to make this routine a class function if
it isn't using class members anyhow.
llvm-svn: 325967
This is the first in a series of patches that will define more
instructions using InstRW so that we can move away from ItinRW
and ultimately have a complete Power 9 scheduler.
Differential Revision: https://reviews.llvm.org/D43635
llvm-svn: 325956
These can be created by type legalization promoting the inputs to select to match scalar boolean contents.
We were trying to pattern match them away during isel, but its better to just remove them from the DAG.
I've cleaned up some patterns to not check for this 'and' anymore. But I suspect this has also opened up opportunities for pattern removal.
llvm-svn: 325949
This feature enables the fusion of the comparison and the conditional select
instructions together.
Differential revision: https://reviews.llvm.org/D42392
llvm-svn: 325939
The test changes you can see are related to the changes in ReplaceNodeResults. Though shuffle-vs-trunc-512.ll does have a test that exercises the code in LowerBITCAST. Looks like the test output didn't change because DAG combining is able to clean up the resulting type legalization. Adding the custom hook just makes type legalization work less hard.
Differential Revision: https://reviews.llvm.org/D43447
llvm-svn: 325933
Summary:
Add a target option AllowRegisterRenaming that is used to opt in to
post-register-allocation renaming of registers. This is set to 0 by
default, which causes the hasExtraSrcRegAllocReq/hasExtraDstRegAllocReq
fields of all opcodes to be set to 1, causing
MachineOperand::isRenamable to always return false.
Set the AllowRegisterRenaming flag to 1 for all in-tree targets that
have lit tests that were effected by enabling COPY forwarding in
MachineCopyPropagation (AArch64, AMDGPU, ARM, Hexagon, Mips, PowerPC,
RISCV, Sparc, SystemZ and X86).
Add some more comments describing the semantics of the
MachineOperand::isRenamable function and how it is set and maintained.
Change isRenamable to check the operand's opcode
hasExtraSrcRegAllocReq/hasExtraDstRegAllocReq bit directly instead of
relying on it being consistently reflected in the IsRenamable bit
setting.
Clear the IsRenamable bit when changing an operand's register value.
Remove target code that was clearing the IsRenamable bit when changing
registers/opcodes now that this is done conservatively by default.
Change setting of hasExtraSrcRegAllocReq in AMDGPU target to be done in
one place covering all opcodes that have constant pipe read limit
restrictions.
Reviewers: qcolombet, MatzeB
Subscribers: aemerson, arsenm, jyknight, mcrosier, sdardis, nhaehnle, javed.absar, tpr, arichardson, kristof.beyls, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, niosHD, escha, nemanjai, llvm-commits
Differential Revision: https://reviews.llvm.org/D43042
llvm-svn: 325931
The following set of instructions was originally planned to be added for Power 9
and so code was added to support them. However, a decision was made later on to
withdraw support for these instructions in the hardware.
xscmpnedp
xvcmpnesp
xvcmpnedp
This patch removes support for the instructions that were not added.
Differential Revision: https://reviews.llvm.org/D43641
llvm-svn: 325918
Summary:
There are transformation that change setcc into other constructs, and transform that try to reconstruct a setcc from the brcond condition. Depending on what order these transform are done, the end result differs.
Most of the time, it is preferable to get a setcc as a brcond argument (and this is why brcond try to recreate the setcc in the first place) so we ensure this is done every time by also doing it at the setcc level when the only user is a brcond.
Reviewers: spatel, hfinkel, niravd, craig.topper
Subscribers: nhaehnle, llvm-commits
Differential Revision: https://reviews.llvm.org/D41235
llvm-svn: 325892
Add GlobalISel infrastructure up to the point where we can select a ret
void.
Patch by Petar Avramovic.
Differential Revision: https://reviews.llvm.org/D43583
llvm-svn: 325888
Summary:
This handles def-after-use of physregs, and allows us to merge loads and
stores even across some physreg defs (typically M0 defs).
Change-Id: I076484b2bda27c2cf46013c845a0380c5b89b67b
Reviewers: arsenm, mareko, rampitec
Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D42647
llvm-svn: 325882
Enable multiple COPY hints to eliminate more COPYs during register allocation.
Note that this is something all targets should do, see
https://reviews.llvm.org/D38128.
Review: Simon Dardis
llvm-svn: 325870
This is combination of two patches by Nicholas Wilson:
1. https://reviews.llvm.org/D41954
2. https://reviews.llvm.org/D42495
Along with a few local modifications:
- One change I made was to add the UNDEFINED bit to the binary format
to avoid the extra byte used when writing data symbols. Although this
bit is redundant for other symbols types (i.e. undefined can be
implied if a function or global is a wasm import)
- I prefer to be explicit and consistent and not have derived flags.
- Some field renaming.
- Some reverting of unrelated minor changes.
- No test output differences.
Differential Revision: https://reviews.llvm.org/D43147
llvm-svn: 325860
We won't be able to fold the constant pool load, but its still better than materialing ones and xoring for the invert if we used PCMPEQ.
This will fix another regression from D42948.
llvm-svn: 325845
Move checks for each fusion case into separate functions for better
legibility and maintainability.
Differential revision: https://reviews.llvm.org/D43649
llvm-svn: 325844
Previously this code overrode the flags and opcode used by the later code in LowerVSETCC. This makes the code difficult to read and follow.
This patch moves all the SUBUS code into its own function and makes it responsible for creating its own SDNodes on success.
Differential Revision: https://reviews.llvm.org/D43530
llvm-svn: 325827
