This updates the AVR Select8/Select16 expansion code so that, when
inserting the two basic blocks for true and false conditions, any
existing fallthrough on the previous block is preserved.
Prior to this patch, if the block before the Select pseudo fell through
to the subsequent block, two new basic blocks would be inserted at the
prior fallthrough point, changing the fallthrough destination.
The predecessor or successor lists were not updated, causing the
BranchFolding pass at -O1 and above the rearrange basic blocks, causing
an infinite loop. Not to mention the unconditional fallthrough to the
true block is incorrect in of itself.
This patch modifies the Select8/16 expansion so that, if inserting true
and false basic blocks at a fallthrough point, the implicit branch is
preserved by means of an explicit, unconditional branch to the previous
fallthrough destination.
Thanks to Carl Peto for reporting this bug.
This fixes avr-rust bug https://github.com/avr-rust/rust/issues/123.
llvm-svn: 351721
Prior to this, the code was missing AVR-specific relocation logic in
RelocVisitor.h.
This patch teaches RelocVisitor about R_AVR_16 and R_AVR_32.
Debug information is emitted in the final object file, and understood by
'avr-readelf --debug-dump' from AVR-GCC.
llvm-dwarfdump is yet to understand how to dump AVR DWARF symbols.
llvm-svn: 351720
This reverts commit r351718.
Carl pointed out that the unit test could be improved.
This patch will be recommitted once the test is made more resilient.
llvm-svn: 351719
This updates the AVR Select8/Select16 expansion code so that, when
inserting the two basic blocks for true and false conditions, any
existing fallthrough on the previous block is preserved.
Prior to this patch, if the block before the Select pseudo fell through
to the subsequent block, two new basic blocks would be inserted at the
prior fallthrough point, changing the fallthrough destination.
The predecessor or successor lists were not updated, causing the
BranchFolding pass at -O1 and above the rearrange basic blocks, causing
an infinite loop. Not to mention the unconditional fallthrough to the
true block is incorrect in of itself.
This patch modifies the Select8/16 expansion so that, if inserting true
and false basic blocks at a fallthrough point, the implicit branch is
preserved by means of an explicit, unconditional branch to the previous
fallthrough destination.
Thanks to Carl Peto for reporting this bug.
This fixes avr-rust bug https://github.com/avr-rust/rust/issues/123.
llvm-svn: 351718
These were originally introduced in a copy-paste committed in r351526.
The reference to 't2_so_imm' have been updated to 'imm_com8' so the
comment is now accurate.
Thanks to Eli Friedman for noticing this.
llvm-svn: 351674
Prior to this patch, the AVR::LDWRdPtr instruction was always lowered to
instructions of this pattern:
ld $GPR8, [PTR:XYZ]+
ld $GPR8, [PTR]+1
This has a problem; the [PTR] is incremented in-place once, but never
decremented.
Future uses of the same pointer will use the now clobbered value,
leading to the pointer being incorrect by an offset of one.
This patch modifies the expansion code of the LDWRdPtr pseudo
instruction so that the pointer variable is not silently clobbered in
future uses in the same live range.
Bug first reported by Keshav Kini.
Patch by Kaushik Phatak.
llvm-svn: 351673
This reverts commit r351544.
In that commit, I had mistakenly misattributed the issue submitter as
the patch author, Kaushik Phatak.
The patch will be recommitted immediately with the correct attribution.
llvm-svn: 351672
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
Prior to this patch, the AVR::LDWRdPtr instruction was always lowered to
instructions of this pattern:
ld $GPR8, [PTR:XYZ]+
ld $GPR8, [PTR]+1
This has a problem; the [PTR] is incremented in-place once, but never
decremented.
Future uses of the same pointer will use the now clobbered value,
leading to the pointer being incorrect by an offset of one.
This patch modifies the expansion code of the LDWRdPtr pseudo
instruction so that the pointer variable is not silently clobbered in
future uses in the same live range.
Patch by Keshav Kini.
llvm-svn: 351544
The CBR instruction is just an ANDI instruction with the immediate
complemented.
Because of this, prior to this change TableGen would warn due to a
decoding conflict.
This commit fixes the existing compilation warning:
===============
[423/492] Building AVRGenDisassemblerTables.inc...
Decoding Conflict:
0111............
01..............
................
ANDIRdK 0111____________
CBRRdK 0111____________
================
After this commit, there are no more decoding conflicts in the AVR
backend's instruction definitions.
Thanks to Eli F for pointing me torward `t2_so_imm_not` as an example of
how to perform a complement in an instruction alias.
Fixes BugZilla PR38802.
llvm-svn: 351526
This change modifies the LLVM ISel lowering settings so that
8-bit/16-bit multiplication is expanded to calls into the compiler
runtime library if the MCU being targeted does not support
multiplication in hardware.
Before this, MUL instructions would be generated on CPUs like the
ATtiny85, triggering a CPU reset due to an illegal instruction at
runtime.
First raised in https://github.com/avr-rust/rust/issues/124.
llvm-svn: 351523
Adds fatal errors for any target that does not support the Tiny or Kernel
codemodels by rejigging the getEffectiveCodeModel calls.
Differential Revision: https://reviews.llvm.org/D50141
llvm-svn: 348585
Summary:
Without this change I get the following error:
lib/Target/AVR/AVRGenAsmMatcher.inc:1135:1: error: redundant #include of module 'LLVM_Utils.Support.Format' appears within namespace 'llvm' [-Wmodules-import-nested-redundant]
Reviewers: dylanmckay
Reviewed By: dylanmckay
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D53425
llvm-svn: 346750
This patch fixes a bug in the AVR FRMIDX expansion logic.
The expansion would leave a leftover operand from the original FRMIDX,
but now attached to a MOVWRdRr instruction. The MOVWRdRr instruction
did not expect this operand and so LLVM rejected the machine
instruction.
This would trigger an assertion:
Assertion failed: ((isImpReg || Op.isRegMask() || MCID->isVariadic() ||
OpNo < MCID->getNumOperands() || isMetaDataOp) &&
"Trying to add an operand to a machine instr that is already done!"),
function addOperand, file llvm/lib/CodeGen/MachineInstr.cpp
Tim fixed this so that now the FRMIDX is expanded correctly into
a well-formed MOVWRdRr.
Patch by Tim Neumann
llvm-svn: 346117
This is an AVR-specific workaround for a limitation of the register
allocator that only exposes itself on targets with high register
contention like AVR, which only has three pointer registers.
The three pointer registers are X, Y, and Z.
In most nontrivial functions, Y is reserved for the frame pointer,
as per the calling convention. This leaves X and Z. Some instructions,
such as LPM ("load program memory"), are only defined for the Z
register. Sometimes this just leaves X.
When the backend generates a LDDWRdPtrQ instruction with Z as the
destination pointer, it usually trips up the register allocator
with this error message:
LLVM ERROR: ran out of registers during register allocation
This patch is a hacky workaround. We ban the LDDWRdPtrQ instruction
from ever using the Z register as an operand. This gives the
register allocator a bit more space to allocate, fixing the
regalloc exhaustion error.
Here is a description from the patch author Peter Nimmervoll
As far as I understand the problem occurs when LDDWRdPtrQ uses
the ptrdispregs register class as target register. This should work, but
the allocator can't deal with this for some reason. So from my testing,
it seams like (and I might be totally wrong on this) the allocator reserves
the Z register for the ICALL instruction and then the register class
ptrdispregs only has 1 register left and we can't use Y for source and
destination. Removing the Z register from DREGS fixes the problem but
removing Y register does not.
More information about the bug can be found on the avr-rust issue
tracker at https://github.com/avr-rust/rust/issues/37.
A bug has raised to track the removal of this workaround and a proper
fix; PR39553 at https://bugs.llvm.org/show_bug.cgi?id=39553.
Patch by Peter Nimmervoll
llvm-svn: 346114
The 'rol Rd' instruction is equivalent to 'adc Rd'.
This caused compile warnings from tablegen because of conflicting bits
shared between each instruction.
llvm-svn: 341275
a generically extensible collection of extra info attached to
a `MachineInstr`.
The primary change here is cleaning up the APIs used for setting and
manipulating the `MachineMemOperand` pointer arrays so chat we can
change how they are allocated.
Then we introduce an extra info object that using the trailing object
pattern to attach some number of MMOs but also other extra info. The
design of this is specifically so that this extra info has a fixed
necessary cost (the header tracking what extra info is included) and
everything else can be tail allocated. This pattern works especially
well with a `BumpPtrAllocator` which we use here.
I've also added the basic scaffolding for putting interesting pointers
into this, namely pre- and post-instruction symbols. These aren't used
anywhere yet, they're just there to ensure I've actually gotten the data
structure types correct. I'll flesh out support for these in
a subsequent patch (MIR dumping, parsing, the works).
Finally, I've included an optimization where we store any single pointer
inline in the `MachineInstr` to avoid the allocation overhead. This is
expected to be the overwhelmingly most common case and so should avoid
any memory usage growth due to slightly less clever / dense allocation
when dealing with >1 MMO. This did require several ergonomic
improvements to the `PointerSumType` to reasonably support the various
usage models.
This also has a side effect of freeing up 8 bits within the
`MachineInstr` which could be repurposed for something else.
The suggested direction here came largely from Hal Finkel. I hope it was
worth it. ;] It does hopefully clear a path for subsequent extensions
w/o nearly as much leg work. Lots of thanks to Reid and Justin for
careful reviews and ideas about how to do all of this.
Differential Revision: https://reviews.llvm.org/D50701
llvm-svn: 339940
This sets trackLivenessAfterRegAlloc on AVRRegisterInfo.
Most existing targets set this flag. Without it, specific IR inputs
cause LLVM to fail with:
Assertion failed: (getParent()->getProperties().hasProperty( MachineFunctionProperties::Property::TracksLiveness) &&
"Liveness information is accurate"), function livein_begin
file MachineBasicBlock.cpp, line 1354.
With this commit, this no longer happens.
Patch by Peter Nimmervoll.
llvm-svn: 334409
With this we gain a little flexibility in how the generic object
writer is created.
Part of PR37466.
Differential Revision: https://reviews.llvm.org/D47045
llvm-svn: 332868
To make this work I needed to add an endianness field to MCAsmBackend
so that writeNopData() implementations know which endianness to use.
Part of PR37466.
Differential Revision: https://reviews.llvm.org/D47035
llvm-svn: 332857
The idea is that a client that wants split dwarf would create a
specific kind of object writer that creates two files, and use it to
create the streamer.
Part of PR37466.
Differential Revision: https://reviews.llvm.org/D47050
llvm-svn: 332749
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
llvm-svn: 332240
Because we create a new kind of debug instruction, DBG_LABEL, we need to
check all passes which use isDebugValue() to check MachineInstr is debug
instruction or not. When expelling debug instructions, we should expel
both DBG_VALUE and DBG_LABEL. So, I create a new function,
isDebugInstr(), in MachineInstr to check whether the MachineInstr is
debug instruction or not.
This patch has no new test case. I have run regression test and there is
no difference in regression test.
Differential Revision: https://reviews.llvm.org/D45342
Patch by Hsiangkai Wang.
llvm-svn: 331844
They were added in r285274, in what looks like a merge mishap.
AVRGenMCCodeEmitter.inc is the only non-dupe tablegen invocation added in that
revision.
Also sort the tablegen lines to make this easier to spot in the future.
llvm-svn: 329178
This patch adds i128 division support by instruction LLVM to lower
128-bit divisions to the __udivmodti4 and __divmodti4 rtlib functions.
This also adds test for 64-bit division and 128-bit division.
Patch by Peter Nimmervoll.
llvm-svn: 327814
Before I started maintaining the AVR backend, this instruction
never originally used to have an earlyclobber flag.
Some time afterwards (years ago), I must've added it back in, not realising that it
was left out for a reason.
This pseudo instrction exists solely to work around a long standing bug
in the register allocator.
Before this commit, the LDDWRdYQ pseudo was not actually working around
any bug. With the earlyclobber flag removed again, the LDDWRdYQ pseudo
now correctly works around PR13375 again.
llvm-svn: 326774
This adds the program memory address space setting to the AVR data
layout.
This setting was very recently added under r325479.
At the moment, there are no uses of this setting. In the future, things
such as switch lookup tables should reside there.
llvm-svn: 325481
The parseFunctionArgs() method was directly reading the
arguments from a Function object, but is should have used the
arguments supplied by the SelectionDAGBuilder.
This was causing
the lowering code to only lower one argument, not two in some cases.
Thanks to @brainlag on GitHub for coming up with the working fix!
Patch-by: @brainlag on GitHub
llvm-svn: 325474
Previously some targets printed their own message at the start of Select to indicate what they were selecting. For the targets that didn't, it means there was no print of the root node before any custom handling in the target executed. So if the target did something custom and never called SelectNodeCommon, no print would be made. For the targets that did print a message in Select, if they didn't custom handle a node SelectNodeCommon would reprint the root node before walking the isel table.
It seems better to just print the message before the call to Select so all targets behave the same. And then remove the root node printing from SelectNodeCommon and just leave a message that says we're starting the table search.
There were also some oddities in blank line behavior. Usually due to a \n after a call to SelectionDAGNode::dump which already inserted a new line.
llvm-svn: 323551
Summary:
This relaxes an assertion inside SelectionDAGBuilder which is overly
restrictive on targets which have no concept of alignment (such as AVR).
In these architectures, all types are aligned to 8-bits.
After this, LLVM will only assert that accesses are aligned on targets
which actually require alignment.
This patch follows from a discussion on llvm-dev a few months ago
http://llvm.1065342.n5.nabble.com/llvm-dev-Unaligned-atomic-load-store-td112815.html
Reviewers: bogner, nemanjai, joerg, efriedma
Reviewed By: efriedma
Subscribers: efriedma, cactus, llvm-commits
Differential Revision: https://reviews.llvm.org/D39946
llvm-svn: 320243
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).
llvm-svn: 318490
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.
llvm-svn: 317647
This header already includes a CodeGen header and is implemented in
lib/CodeGen, so move the header there to match.
This fixes a link error with modular codegeneration builds - where a
header and its implementation are circularly dependent and so need to be
in the same library, not split between two like this.
llvm-svn: 317379