Since we have distinct types for pointers and scalars, G_INTTOPTRs can sometimes
obstruct attempts to find constant source values. These usually come about when
try to do some kind of null pointer check. Teaching getConstantVRegValWithLookThrough
about this operation allows the CBZ/CBNZ optimization to catch more cases.
This change also improves the case where we can't find a constant source at all.
Previously we would emit a cmp, cset and tbnz for that. Now we try to just emit
a cmp and conditional branch, saving an instruction.
The cumulative code size improvement of this change plus D64354 is 5.5% geomean
on arm64 CTMark -O0.
Differential Revision: https://reviews.llvm.org/D64377
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365690 91177308-0d34-0410-b5e6-96231b3b80d8
When constrainRegClass is called if the constraining happens on a use the COPY
needs to be inserted before the instruction that contains the MachineOperand,
but if we are constraining a definition it actually needs to be added
after the instruction. In addition, the COPY needs to have its operands
flipped (in the use case we are copying from the old unconstrained register
to the new constrained register, while in the definition case we are copying
from the new constrained register that the instruction defines to the old
unconstrained register).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@359282 91177308-0d34-0410-b5e6-96231b3b80d8
getConstantVRegVal used to only look for G_CONSTANT when looking at
unboxing the value of a vreg. However, constants are sometimes not
directly used and are hidden behind trunc, s|zext or copy chain of
computation.
In particular this may be introduced by the legalization process that
doesn't want to simplify these patterns because it can lead to infine
loop when legalizing a constant.
To circumvent that problem, add a new variant of getConstantVRegVal,
named getConstantVRegValWithLookThrough, that allow to look through
extensions.
Differential Revision: https://reviews.llvm.org/D59227
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356116 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351636 91177308-0d34-0410-b5e6-96231b3b80d8
This re-applies r336929 with a fix to accomodate for the Mips target
scheduling multiple SelectionDAG instances into the pass pipeline.
PrologEpilogInserter and StackColoring depend on the StackProtector analysis
being alive from the point it is run until PEI, which requires that they are all
scheduled in the same FunctionPassManager. Inserting a (machine) ModulePass
between StackProtector and PEI results in these passes being in separate
FunctionPassManagers and the StackProtector is not available for PEI.
PEI and StackColoring don't use much information from the StackProtector pass,
so transfering the required information to MachineFrameInfo is cleaner than
keeping the StackProtector pass around. This commit moves the SSP layout
information to MFI instead of keeping it in the pass.
This patch set (D37580, D37581, D37582, D37583, D37584, D37585, D37586, D37587)
is a first draft of the pagerando implementation described in
http://lists.llvm.org/pipermail/llvm-dev/2017-June/113794.html.
Patch by Stephen Crane <sjc@immunant.com>
Differential Revision: https://reviews.llvm.org/D49256
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@336964 91177308-0d34-0410-b5e6-96231b3b80d8
PrologEpilogInserter and StackColoring depend on the StackProtector analysis
being alive from the point it is run until PEI, which requires that they are all
scheduled in the same FunctionPassManager. Inserting a (machine) ModulePass
between StackProtector and PEI results in these passes being in separate
FunctionPassManagers and the StackProtector is not available for PEI.
PEI and StackColoring don't use much information from the StackProtector pass,
so transfering the required information to MachineFrameInfo is cleaner than
keeping the StackProtector pass around. This commit moves the SSP layout
information to MFI instead of keeping it in the pass.
This patch set (D37580, D37581, D37582, D37583, D37584, D37585, D37586, D37587)
is a first draft of the pagerando implementation described in
http://lists.llvm.org/pipermail/llvm-dev/2017-June/113794.html.
Patch by Stephen Crane <sjc@immunant.com>
Differential Revision: https://reviews.llvm.org/D49256
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@336929 91177308-0d34-0410-b5e6-96231b3b80d8
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.
In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.
Differential Revision: https://reviews.llvm.org/D43624
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332240 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
constrainOperandRegClass() currently fails if it tries to constrain the
register class of an operand that is defeined with an unallocatable register
class. This patch resolves this by adding a target callback to compute
register constriants in this case.
This is required by the AMDGPU because many of its instructions have source opreands
defined with the unallocatable register classe VS_32 which is a union of two allocatable
register classes VGPR_32 and SReg_32.
Reviewers: dsanders, aditya_nandakumar
Reviewed By: aditya_nandakumar
Subscribers: rovka, kristof.beyls, tpr, llvm-commits
Differential Revision: https://reviews.llvm.org/D45991
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331485 91177308-0d34-0410-b5e6-96231b3b80d8
Added helpers to build G_FCONSTANT, along with matching ConstantFP and
unit tests for the same.
Sample usage.
auto MIB = Builder.buildFConstant(s32, 0.5); // Build IEEESingle
For Matching the above
const ConstantFP* Tmp;
mi_match(DstReg, MRI, m_GFCst(Tmp));
https://reviews.llvm.org/D44128
reviewed by: volkan
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@327152 91177308-0d34-0410-b5e6-96231b3b80d8
Currently when abort is enabled, we get a diagnostic saying "Fallback
path used .... " and the program terminates. To actually figure out what
the reason is, we need to run again with another verbose argument
"-pass-remarks-missed=gisel". Instead, when we are going to abort,
we might as well print expensive remarks.
https://reviews.llvm.org/D43796
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326215 91177308-0d34-0410-b5e6-96231b3b80d8
Currently we assert that only non target specific opcodes can have
missing RegisterClass constraints in the MCDesc. The backend can have
instructions with register operands but don't have RegisterClass
constraints (say using unknown_class) in which case the instruction
defining the register will constrain it.
Change the assert to only fire if a def has no regclass.
https://reviews.llvm.org/D43409
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326142 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Apparently, we missed on constraining register classes of VReg-operands of all the instructions
built from a destination pattern but the root (top-level) one. The issue exposed itself
while selecting G_FPTOSI for armv7: the corresponding pattern generates VTOSIZS wrapped
into COPY_TO_REGCLASS, so top-level COPY_TO_REGCLASS gets properly constrained,
while nested VTOSIZS (or rather its destination virtual register to be exact) does not.
Fixing this by issuing GIR_ConstrainSelectedInstOperands for every nested GIR_BuildMI.
https://bugs.llvm.org/show_bug.cgi?id=35965
rdar://problem/36886530
Patch by Roman Tereshin
Reviewers: dsanders, qcolombet, rovka, bogner, aditya_nandakumar, volkan
Reviewed By: dsanders, qcolombet, rovka
Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D42565
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@323692 91177308-0d34-0410-b5e6-96231b3b80d8
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318490 91177308-0d34-0410-b5e6-96231b3b80d8
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317647 91177308-0d34-0410-b5e6-96231b3b80d8
r313390 taught 'allowExtraAnalysis' to check whether remarks are
enabled at all. Use that to only do the expensive instruction printing
if they are.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@313552 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
As part of this
* Emitted instructions now have named MachineInstr variables associated
with them. This isn't particularly important yet but it's a small step
towards multiple-insn emission.
* constrainSelectedInstRegOperands() is no longer hardcoded. It's now added
as the ConstrainOperandsToDefinitionAction() action. COPY_TO_REGCLASS uses
an alternate constraint mechanism ConstrainOperandToRegClassAction() which
supports arbitrary constraints such as that defined by COPY_TO_REGCLASS.
Reviewers: ab, qcolombet, t.p.northover, rovka, kristof.beyls, aditya_nandakumar
Reviewed By: ab
Subscribers: javed.absar, igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D33590
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305791 91177308-0d34-0410-b5e6-96231b3b80d8
Quentin points out that r298358 would cause us to emit different code
with debug info. That's a big no-no; also erase the instructions that
only live thanks to DBG_VALUE users.
Adrian explained how this is an existing problem and an OK thing to do:
clang has allocas for all variables so shouldn't be affected at -O0, but
swift uses a bit of inlineasm to explicitly keep values live for the
purpose of debug info quality. I'm not sure there is a better scheme.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298460 91177308-0d34-0410-b5e6-96231b3b80d8
Having more fine-grained information on the specific construct that
caused us to fallback is valuable for large-scale data collection.
We still have the fallback warning, that's also used for FastISel.
We still need to remove the fallback warning, and teach FastISel to also
emit remarks (it currently has a combination of the warning, stats, and
debug prints: the remarks could unify all three).
The abort-on-fallback path could also be better handled using remarks:
one could imagine a "-Rpass-error", analoguous to "-Werror", which would
promote missed/failed remarks to errors. It's not clear whether that
would be useful for other remarks though, so we're not there yet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296013 91177308-0d34-0410-b5e6-96231b3b80d8
Move the logic to constraint register from InstructionSelector to a
utility function. It will be required by other passes in the GlobalISel
pipeline.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290374 91177308-0d34-0410-b5e6-96231b3b80d8
