This commit translates the source locations for MIParser diagnostics from
the locations in the machine instruction string to the locations in the
MIR file.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10574
llvm-svn: 240474
This commit introduces functionality that's used to serialize machine operands.
Only the physical register operands are serialized by this commit.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10525
llvm-svn: 240425
The summary is that it moves the mangling earlier and replaces a few
calls to .addExternalSymbol with addSym.
I originally wanted to replace all the uses of addExternalSymbol with
addSym, but noticed it was a lot of work and doesn't need to be done
all at once.
llvm-svn: 240395
Summary:
That way llvm-objdump can rely on it without adding an extra dependency
on CodeGen.
This change duplicates the FaultKind enum and the code that serializes
it to a string. I could not figure out a way to get around this without
adding a new dependency to Object
Reviewers: rafael, ab
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10619
llvm-svn: 240364
Currently ( D10321, http://reviews.llvm.org/rL239486 ), we can use the machine combiner pass
to reassociate the following sequence to reduce the critical path:
A = ? op ?
B = A op X
C = B op Y
-->
A = ? op ?
B = X op Y
C = A op B
'op' is currently limited to x86 AVX scalar FP adds (with fast-math on), but in theory, it could
be any associative math/logic op (see TODO in code comment).
This patch generalizes the pattern match to ignore the instruction that defines 'A'. So instead of
a sequence of 3 adds, we now only need to find 2 dependent adds and decide if it's worth
reassociating them.
This generalization has a compile-time cost because we can now match more instruction sequences
and we rely more heavily on the machine combiner to discard sequences where reassociation doesn't
improve the critical path.
For example, in the new test case:
A = M div N
B = A add X
C = B add Y
We'll match 2 reassociation patterns, but this transform doesn't reduce the critical path:
A = M div N
B = A add Y
C = B add X
We need the combiner to reject that pattern but select this:
A = M div N
B = X add Y
C = B add A
Differential Revision: http://reviews.llvm.org/D10460
llvm-svn: 240361
This commit adds a function that tokenizes the string containing
the machine instruction. This commit also adds a struct called
'MIToken' which is used to represent the lexer's tokens.
Reviewers: Sean Silva
Differential Revision: http://reviews.llvm.org/D10521
llvm-svn: 240323
I had some unnecessary `typename`s left in after addressing review.
This compiled successfully with clang++ but MSVC reported an error. Fix
the build error by removing the redundant `typename`s.
llvm-svn: 240307
Summary:
The parser is exercised by llvm-objdump using -print-fault-maps. As is
probably obvious, the code itself was "heavily inspired" by
http://reviews.llvm.org/D10434.
Reviewers: reames, atrick, JosephTremoulet
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10491
llvm-svn: 240304
Before this we were producing a TargetExternalSymbol from a MCSymbol.
That meant extracting the symbol name and fetching the symbol again
down the pipeline.
This patch adds a DAG.getMCSymbol that lets the MCSymbol pass unchanged on the
DAG.
Doing so removes the need for MO_NOPREFIX and fixes the root cause of pr23900,
allowing r240130 to be committed again.
llvm-svn: 240300
This commit implements initial machine instruction serialization. It
serializes machine instruction names. The instructions are represented
using a YAML sequence of string literals and are a part of machine
basic block YAML mapping.
This commit introduces a class called 'MIParser' which will be used to
parse the machine instructions and operands.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10481
llvm-svn: 240295
Summary: The code responsible for shl folding in the DAGCombiner was assuming incorrectly that all constants are less than 64 bits. This patch simply changes the way values are compared.
Test Plan: A regression test included.
Reviewers: andreadb
Reviewed By: andreadb
Subscribers: andreadb, test, llvm-commits
Differential Revision: http://reviews.llvm.org/D10602
llvm-svn: 240291
This will allow classes to implement the AA interface without deriving
from the class or referencing an internal enum of some other class as
their return types.
Also, to a pretty fundamental extent, concepts such as 'NoAlias',
'MayAlias', and 'MustAlias' are first class concepts in LLVM and we
aren't saving anything by scoping them heavily.
My mild preference would have been to use a scoped enum, but that
feature is essentially completely broken AFAICT. I'm extremely
disappointed. For example, we cannot through any reasonable[1] means
construct an enum class (or analog) which has scoped names but converts
to a boolean in order to test for the possibility of aliasing.
[1]: Richard Smith came up with a "solution", but it requires class
templates, and lots of boilerplate setting up the enumeration multiple
times. Something like Boost.PP could potentially bundle this up, but
even that would be quite painful and it doesn't seem realistically worth
it. The enum class solution would probably work without the need for
a bool conversion.
Differential Revision: http://reviews.llvm.org/D10495
llvm-svn: 240255
If we don't know how to represent a .debug_loc entry, skip the entry
entirely rather than emitting an empty one. Similarly, if a .debug_loc
list has no entries, don't create the list.
We still want to create the variables, just in an optimized-out form
that doesn't have a DW_AT_location.
llvm-svn: 240244
There are three types of `DbgVariable`:
- alloca variables, created based on the MMI table,
- register variables, created based on DBG_VALUE instructions, and
- optimized-out variables.
This commit reconfigures `DbgVariable` to make it easier to tell which
kind we have, and make initialization a little clearer.
For MMI/alloca variables, `FrameIndex.size()` must always equal
`Expr.size()`, and there shouldn't be an `MInsn`. For register
variables (with a `MInsn`), `FrameIndex` must be empty, and `Expr`
should have 0 or 1 element depending on whether it has a complex
expression (registers with multiple locations use `DebugLocListIndex`).
Optimized-out variables shouldn't have any of these fields.
Moreover, this separates DBG_VALUE initialization until after the
variable is created, simplifying logic in a future commit that changes
`collectVariableInfo()` to stop creating empty .debug_loc entries/lists.
llvm-svn: 240243
Sparse switches with profile info are lowered as weight-balanced BSTs. For
example, if the node weights are {1,1,1,1,1,1000}, the right-most node would
end up in a tree by itself, bringing it closer to the top.
However, a leaf in this BST can contain up to 3 cases, and having a single
case in a leaf node as in the example means the tree might become
unnecessarily high.
This patch adds a heauristic to the pivot selection algorithm that moves more
cases into leaf nodes unless that would lower their rank. It still doesn't
yield the optimal tree in every case, but I believe it's conservatibely correct.
llvm-svn: 240224
This commit implements the initial serialization of machine basic blocks in a
machine function. Only the simple, scalar MBB attributes are serialized. The
reference to LLVM IR's basic block is preserved when that basic block has a name.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10465
llvm-svn: 240145
The patch is generated using this command:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
llvm/lib/
Thanks to Eugene Kosov for the original patch!
llvm-svn: 240137
To same compile time, the analysis to find dense case-clusters in switches is
not done at -O0. However, when the whole switch is dense enough, it is easy to
turn it into a jump table, resulting in much faster code with no extra effort.
llvm-svn: 240071
- zext the value to alloc size first, then check if the value repeats
with zero padding included. If so we can still emit a .space
- Do the checking with APInt.isSplat(8), which handles non-pow2 types
- Also handle large constants (bit width > 64)
- In a ConstantArray all elements have the same type, so it's sufficient
to check the first constant recursively and then just compare if all
following constants are the same by pointer compare
llvm-svn: 239977
The personality routine currently lives in the LandingPadInst.
This isn't desirable because:
- All LandingPadInsts in the same function must have the same
personality routine. This means that each LandingPadInst beyond the
first has an operand which produces no additional information.
- There is ongoing work to introduce EH IR constructs other than
LandingPadInst. Moving the personality routine off of any one
particular Instruction and onto the parent function seems a lot better
than have N different places a personality function can sneak onto an
exceptional function.
Differential Revision: http://reviews.llvm.org/D10429
llvm-svn: 239940
It's been used before to avoid infinite loops caused by separate CGP
optimizations undoing one another. We found one more such issue
caused by r238054. To avoid it, generalize the "InsertedTruncs"
set to any inst, and use it to avoid touching those again.
llvm-svn: 239938
that it is its own entity in the form of MemoryLocation, and update all
the callers.
This is an entirely mechanical change. References to "Location" within
AA subclases become "MemoryLocation", and elsewhere
"AliasAnalysis::Location" becomes "MemoryLocation". Hope that helps
out-of-tree folks update.
llvm-svn: 239885
Different object formats represent references from dwarf in different ways.
ELF uses a relocation to the referenced point (except for .dwo) and
COFF/MachO use the offset of the referenced point inside its section.
This patch renames emitSectionOffset because
* It doesn't produce an offset on ELF.
* It changes behavior depending on how DWARF is represented, so adding
dwarf to its name is probably a good thing.
The patch also adds an option to force the use of offsets.That avoids
funny looking code like
if (!UseOffsets)
Asm->emitSectionOffset....
It was correct, but read as if the ! was inverted.
llvm-svn: 239866
While completely undefined registers are easy to catch and get their
<undef> flag early in ProcessImplicitDefs/RegisterCoalescer reading from
a partially defined register where just the subreg happens to be
undefined is harder to catch so we only add the undef flag in the
virtual register rewriting step.
No testcase as I cannot reproduce the problem on any of the in-tree targets at
the moment.
This fixes rdar://21387089
Differential Revision: http://reviews.llvm.org/D10470
llvm-svn: 239838
LaneMasks as given by getSubRegIndexLaneMask() have a limited number of
of bits, so for targets with more than 31 disjunct subregister there may
be cases where:
getSubReg(Reg,A) does not overlap getSubReg(Reg,B)
but we still have
(getSubRegIndexLaneMask(A) & getSubRegIndexLaneMask(B)) != 0.
I had hoped to keep this an implementation detail of the tablegen but as
my next commit shows we can avoid unnecessary imp-defs operands if we
know that the lane masks in use are precise.
This is in preparation to http://reviews.llvm.org/D10470.
llvm-svn: 239837
This commit reports an error when a machine function from a MIR file that contains
LLVM IR can't find a function with the same name in the loaded LLVM IR module.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10468
llvm-svn: 239831
This is an updated version of the patch that was checked in at:
http://reviews.llvm.org/rL237046
but subsequently reverted because it exposed a bug in the DAG Combiner:
http://reviews.llvm.org/D9893
This time, there's an enablement flag ("EnableFMFInDAG") around the code in
SelectionDAGBuilder where we copy the set of FP optimization flags from IR
instructions to DAG nodes. So, in theory, there should be no functional change
from this patch as-is, but it will allow testing with the added functionality
to proceed via "-enable-fmf-dag" passed to llc.
This patch adds the minimum plumbing necessary to use IR-level
fast-math-flags (FMF) in the backend without actually using
them for anything yet. This is a follow-on to:
http://reviews.llvm.org/rL235997
Differential Revision: http://reviews.llvm.org/D10403
llvm-svn: 239828
Reapply r239539. Don't assume the collected number of
stores is the same vector size. Just take the first N
stores to fill the vector.
llvm-svn: 239825
Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.
Reviewers: rengolin
Reviewed By: rengolin
Subscribers: llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D10381
llvm-svn: 239815
This commit serializes the simple, scalar attributes from the
'MachineFunction' class.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10449
llvm-svn: 239790
This commit decouples the MIR printer and the MIR printing pass so
that it will be possible to move the MIR printer into a separate
machine IR library later on.
Reviewers: Duncan P. N. Exon Smith
llvm-svn: 239788
This commit creates a dummy LLVM IR function with one basic block and an unreachable
instruction for each parsed machine function when the MIR file doesn't have LLVM IR.
This change is required as the machine function analysis pass creates machine
functions only for the functions that are defined in the current LLVM module.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10135
llvm-svn: 239778
This commit reports an error when the MIR parser encounters a machine
function with the name that is the same as the name of a different
machine function.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10130
llvm-svn: 239774
This patch adds the safe stack instrumentation pass to LLVM, which separates
the program stack into a safe stack, which stores return addresses, register
spills, and local variables that are statically verified to be accessed
in a safe way, and the unsafe stack, which stores everything else. Such
separation makes it much harder for an attacker to corrupt objects on the
safe stack, including function pointers stored in spilled registers and
return addresses. You can find more information about the safe stack, as
well as other parts of or control-flow hijack protection technique in our
OSDI paper on code-pointer integrity (http://dslab.epfl.ch/pubs/cpi.pdf)
and our project website (http://levee.epfl.ch).
The overhead of our implementation of the safe stack is very close to zero
(0.01% on the Phoronix benchmarks). This is lower than the overhead of
stack cookies, which are supported by LLVM and are commonly used today,
yet the security guarantees of the safe stack are strictly stronger than
stack cookies. In some cases, the safe stack improves performance due to
better cache locality.
Our current implementation of the safe stack is stable and robust, we
used it to recompile multiple projects on Linux including Chromium, and
we also recompiled the entire FreeBSD user-space system and more than 100
packages. We ran unit tests on the FreeBSD system and many of the packages
and observed no errors caused by the safe stack. The safe stack is also fully
binary compatible with non-instrumented code and can be applied to parts of
a program selectively.
This patch is our implementation of the safe stack on top of LLVM. The
patches make the following changes:
- Add the safestack function attribute, similar to the ssp, sspstrong and
sspreq attributes.
- Add the SafeStack instrumentation pass that applies the safe stack to all
functions that have the safestack attribute. This pass moves all unsafe local
variables to the unsafe stack with a separate stack pointer, whereas all
safe variables remain on the regular stack that is managed by LLVM as usual.
- Invoke the pass as the last stage before code generation (at the same time
the existing cookie-based stack protector pass is invoked).
- Add unit tests for the safe stack.
Original patch by Volodymyr Kuznetsov and others at the Dependable Systems
Lab at EPFL; updates and upstreaming by myself.
Differential Revision: http://reviews.llvm.org/D6094
llvm-svn: 239761
This commit connects the machine function analysis pass (which creates machine
functions) to the MIR parser, which will initialize the machine functions
with the state from the MIR file and reconstruct the machine IR.
This commit introduces a new interface called 'MachineFunctionInitializer',
which can be used to provide custom initialization for the machine functions.
This commit also introduces a new diagnostic class called
'DiagnosticInfoMIRParser' which is used for MIR parsing errors.
This commit modifies the default diagnostic handling in LLVMContext - now the
the diagnostics are printed directly into llvm::errs() so that the MIR parsing
errors can be printed with colours.
Reviewers: Justin Bogner
Differential Revision: http://reviews.llvm.org/D9928
llvm-svn: 239753
Summary:
TargetInstrInfo::getLdStBaseRegImmOfs to
TargetInstrInfo::getMemOpBaseRegImmOfs and implement for x86. The
implementation only handles a few easy cases now and will be made more
sophisticated in the future.
This is NFCI: the only user of `getLdStBaseRegImmOfs` (now
`getmemOpBaseRegImmOfs`) is `LoadClusterMotion` and `LoadClusterMotion`
is disabled for x86.
Reviewers: reames, ab, MatzeB, atrick
Reviewed By: MatzeB, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10199
llvm-svn: 239741
Summary:
This instruction encodes a loading operation that may fault, and a label
to branch to if the load page-faults. The locations of potentially
faulting loads and their "handler" destinations are recorded in a
FaultMap section, meant to be consumed by LLVM's clients.
Nothing generates FAULTING_LOAD_OP instructions yet, but they will be
used in a future change.
The documentation (FaultMaps.rst) needs improvement and I will update
this diff with a more expanded version shortly.
Depends on D10196
Reviewers: rnk, reames, AndyAyers, ab, atrick, pgavlin
Reviewed By: atrick, pgavlin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10197
llvm-svn: 239740
This patch fixes a compilation time issue, when MachineSink faces PHIs
with a huge number of operands. This can happen for example in goto table
based interpreters, where some basic blocks can have several of those PHIs,
each one with several hundreds operands. MachineSink was spending a
significant time re-building and re-sorting the list of successors of
the current MachineBasicBlock. The computing and sorting of the current
MachineBasicBlock successors is now cached.
llvm-svn: 239720
r213101 changed the behaviour of this method to not only affect the
PostMachineScheduler scheduler but also the PostRAScheduler scheduler,
renaming should make this fact clear. Also document that the preferred
way is to specify this in the scheduling model instead of overriding
this method.
Differential Revision: http://reviews.llvm.org/D10427
llvm-svn: 239659
This will use Itinieraries if available, but will also work if just a
MCSchedModel is available.
Differential Revision: http://reviews.llvm.org/D10428
llvm-svn: 239658
We were putting them in the filter field, which is correct for 64-bit
but wrong for 32-bit.
Also switch the order of scope table entry emission so outermost entries
are emitted first, and fix an obvious state assignment bug.
llvm-svn: 239574
This intrinsic is like framerecover plus a load. It recovers the EH
registration stack allocation from the parent frame and loads the
exception information field out of it, giving back a pointer to an
EXCEPTION_POINTERS struct. It's designed for clang to use in SEH filter
expressions instead of accessing the EXCEPTION_POINTERS parameter that
is available on x64.
This required a minor change to MC to allow defining a label variable to
another absolute framerecover label variable.
llvm-svn: 239567
Summary:
For the moment, TargetMachine::getTargetTriple() still returns a StringRef.
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.
Reviewers: rengolin
Reviewed By: rengolin
Subscribers: ted, llvm-commits, rengolin, jholewinski
Differential Revision: http://reviews.llvm.org/D10362
llvm-svn: 239554
This makes emitAbsoluteSymbolDiff always succeed and moves logic from the asm
printer to it.
The object one now also works on ELF. If two symbols are in the same fragment,
we will never move them apart.
llvm-svn: 239552
Now actually stores the non-zero constant instead of 0.
I somehow forgot to include this part of r238108.
The test change was just an independent instruction order swap,
so just add another check line to satisfy CHECK-NEXT.
llvm-svn: 239539
On large goto table based interpreters, where phi nodes can have (very) large
fan-ins, isLiveOut exhibited poor performances: about 40% of the full
codegen time was spent in PHIElim, sorting MachineBasicBlock addresses.
This patch improve the performances for such cases, and does not show
compile time regressions on the LNT, at bootstrap (llvm+clang+lldb) or
any other benchmarks we have in-house.
llvm-svn: 239510
It hasn't been used since r130964.
This also removes MachineModuleInfo::isUsedFunction and
MachineModuleInfo::AnalyzeModule, both of which were only
there to support UsedFunctions.
llvm-svn: 239501
During statepoint lowering we can sometimes avoid spilling of the value if we know that it was already spilled for previous statepoint.
We were doing this by checking if incoming statepoint value was lowered into load from stack slot. This was working only in boundaries of one basic block.
But instead of looking at the lowered node we can look directly at the llvm-ir value and if it was gc.relocate (or some simple modification of it) look up stack slot for it's derived pointer and reuse stack slot from it. This allows us to look across basic block boundaries.
Differential Revision: http://reviews.llvm.org/D10251
llvm-svn: 239472
Use a "safeseh" string attribute to do this. You would think we chould
just accumulate the set of personalities like we do on dwarf, but this
fails to account for the LSDA-loading thunks we use for
__CxxFrameHandler3. Each of those needs to make it into .sxdata as well.
The string attribute seemed like the most straightforward approach.
llvm-svn: 239448
Summary:
The RegisterScavenger explicitly ignores <kill> flags on operands of
predicated instructions and therefore assumes that such registers remain
live. When it then scavenges such a register, it inserts a spill of this
(killed) register. This is invalid code and gets flagged up by the
verifier.
Nowadays kill flags are set correctly on predicated instructions. This
patch makes the Scavenger respect them.
The bug has so far only been triggered by an internal pass, so I don't
have a test case unfortunately.
Fixes PR23119.
Reviewers: hfinkel, tobiasvk_caf
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9039
llvm-svn: 239439
This gets all the handler info through to the asm printer and we can
look at the .xdata tables now. I've convinced one small catch-all test
case to work, but other than that, it would be a stretch to say this is
functional.
The state numbering algorithm avoids doing any scope reconstruction as
we do for C++ to simplify the implementation.
llvm-svn: 239433
Summary: I noticed an object file with `DW_OP_reg4 DW_OP_breg4 0` as a DWARF expression,
which I traced to a missing break (and `++I`) in this code snippet.
While I was at it, I also added support for a few other corner cases
along the same lines that I could think of.
Test Plan: Hand-crafted test case to exercises these cases is included.
Reviewers: echristo, dblaikie, aprantl
Reviewed By: aprantl
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10302
llvm-svn: 239380
NAKAMURA Takumi