This patch adds the ability to specify via tablegen which processor resources
are load/store queue resources.
A new tablegen class named MemoryQueue can be optionally used to mark resources
that model load/store queues. Information about the load/store queue is
collected at 'CodeGenSchedule' stage, and analyzed by the 'SubtargetEmitter' to
initialize two new fields in struct MCExtraProcessorInfo named `LoadQueueID` and
`StoreQueueID`. Those two fields are identifiers for buffered resources used to
describe the load queue and the store queue.
Field `BufferSize` is interpreted as the number of entries in the queue, while
the number of units is a throughput indicator (i.e. number of available pickers
for loads/stores).
At construction time, LSUnit in llvm-mca checks for the presence of extra
processor information (i.e. MCExtraProcessorInfo) in the scheduling model. If
that information is available, and fields LoadQueueID and StoreQueueID are set
to a value different than zero (i.e. the invalid processor resource index), then
LSUnit initializes its LoadQueue/StoreQueue based on the BufferSize value
declared by the two processor resources.
With this patch, we more accurately track dynamic dispatch stalls caused by the
lack of LS tokens (i.e. load/store queue full). This is also shown by the
differences in two BdVer2 tests. Stalls that were previously classified as
generic SCHEDULER FULL stalls, are not correctly classified either as "load
queue full" or "store queue full".
About the differences in the -scheduler-stats view: those differences are
expected, because entries in the load/store queue are not released at
instruction issue stage. Instead, those are released at instruction executed
stage. This is the main reason why for the modified tests, the load/store
queues gets full before PdEx is full.
Differential Revision: https://reviews.llvm.org/D54957
llvm-svn: 347857
There are quite strong constraints on how you can use the TIED_TO
constraint between MC operands, many of which are currently not
checked until compiler run time.
MachineVerifier enforces that operands can only be tied together in
pairs (no three-way ties), and MachineInstr::tieOperands enforces that
one of the tied operands must be an output operand (def) and the other
must be an input operand (use).
Now we check these at TableGen time, so that if you violate any of
them in a new instruction definition, you find out immediately,
instead of having to wait until you compile something that makes code
generation hit one of those assertions.
Also in this commit, all the error reports in ParseConstraint now
include the name and source location of the def where the problem
happened, so that if you do trigger any of these errors, it's easier
to find the part of your TableGen input where you made the mistake.
The trunk sources already build successfully with this additional
error check, so I think no in-tree target has any of these problems.
Reviewers: fhahn, lhames, nhaehnle, MatzeB
Reviewed By: MatzeB
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D53815
llvm-svn: 347743
`llvm-mca` relies on the predicates to be based on `MCSchedPredicate` in order
to resolve the scheduling for variant instructions. Otherwise, it aborts
the building of the instruction model early.
However, the scheduling model emitter in `TableGen` gives up too soon, unless
all processors use only such predicates.
In order to allow more processors to be used with `llvm-mca`, this patch
emits scheduling transitions if any processor uses these predicates. The
transition emitted for the processors using legacy predicates is the one
specified with `NoSchedPred`, which is based on `MCSchedPredicate`.
Preferably, `llvm-mca` should instead assume a reasonable default when a
variant transition is not based on `MCSchedPredicate` for a given processor.
This issue should be revisited in the future.
Differential revision: https://reviews.llvm.org/D54648
llvm-svn: 347504
A call to @llvm.trap can be expected to be cold (i.e. unlikely to be
reached in a normal program execution).
Outlining paths which unconditionally trap is an important memory
saving. As the hot/cold splitting pass (imho) should not treat all
noreturn calls as cold, explicitly mark @llvm.trap cold so that it can
be outlined.
Split out of https://reviews.llvm.org/D54244.
Differential Revision: https://reviews.llvm.org/D54329
llvm-svn: 346885
Summary:
This simplifies the code and moves everything to tablegen for consistency. This
also prepares the ground for adding issue counters.
Reviewers: gchatelet, john.brawn, jsji
Subscribers: nemanjai, mgorny, javed.absar, kbarton, tschuett, llvm-commits
Differential Revision: https://reviews.llvm.org/D54297
llvm-svn: 346489
Summary:
As a bonus, this arguably improves the code by making it simpler.
gcc 8 on Ubuntu 18.10 reports the following:
==39667==ERROR: AddressSanitizer: stack-use-after-scope on address 0x7fffffff8ae0 at pc 0x555555dbfc68 bp 0x7fffffff8760 sp 0x7fffffff8750
WRITE of size 8 at 0x7fffffff8ae0 thread T0
#0 0x555555dbfc67 in std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_Alloc_hider::_Alloc_hider(char*, std::allocator<char>&&) /usr/include/c++/8/bits/basic_string.h:149
#1 0x555555dbfc67 in std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::basic_string(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&&) /usr/include/c++/8/bits/basic_string.h:542
#2 0x555555dbfc67 in std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::operator+<char, std::char_traits<char>, std::allocator<char> >(char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&&) /usr/include/c++/8/bits/basic_string.h:6009
#3 0x555555dbfc67 in searchableFieldType /home/nha/amd/build/san/llvm-src/utils/TableGen/SearchableTableEmitter.cpp:168
(...)
Address 0x7fffffff8ae0 is located in stack of thread T0 at offset 864 in frame
#0 0x555555dbef3f in searchableFieldType /home/nha/amd/build/san/llvm-src/utils/TableGen/SearchableTableEmitter.cpp:148
Reviewers: fhahn, simon_tatham, kparzysz
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D53931
llvm-svn: 345749
Before this patch, class PredicateExpander only knew how to expand simple
predicates that performed checks on instruction operands.
In particular, the new scheduling predicate syntax was not rich enough to
express checks like this one:
Foo(MI->getOperand(0).getImm()) == ExpectedVal;
Here, the immediate operand value at index zero is passed in input to function
Foo, and ExpectedVal is compared against the value returned by function Foo.
While this predicate pattern doesn't show up in any X86 model, it shows up in
other upstream targets. So, being able to support those predicates is
fundamental if we want to be able to modernize all the scheduling models
upstream.
With this patch, we allow users to specify if a register/immediate operand value
needs to be passed in input to a function as part of the predicate check. Now,
register/immediate operand checks all derive from base class CheckOperandBase.
This patch also changes where TIIPredicate definitions are expanded by the
instructon info emitter. Before, definitions were expanded in class
XXXGenInstrInfo (where XXX is a target name).
With the introduction of this new syntax, we may want to have TIIPredicates
expanded directly in XXXInstrInfo. That is because functions used by the new
operand predicates may only exist in the derived class (i.e. XXXInstrInfo).
This patch is a non functional change for the existing scheduling models.
In future, we will be able to use this richer syntax to better describe complex
scheduling predicates, and expose them to llvm-mca.
Differential Revision: https://reviews.llvm.org/D53880
llvm-svn: 345714
Summary:
The pfm counters are now in the ExegesisTarget rather than the
MCSchedModel (PR39165).
This also compresses the pfm counter tables (PR37068).
Reviewers: RKSimon, gchatelet
Subscribers: mgrang, llvm-commits
Differential Revision: https://reviews.llvm.org/D52932
llvm-svn: 345243
Summary:
Some targets have very long encodings and uint64_t isn't sufficient. uint128_t
isn't portable so such targets need to use an object instead.
There is one catch with this at the moment, no string of bits extracted
from the encoding may exceeed 64-bits. Fields are still permitted to
exceed 64-bits so long as they aren't one contiguous string of bits. If
this proves to be a problem then we can modify the generation of
fieldFromInstruction() calls to account for it but for now I've added an
assertion for this.
InsnType must either be integral or an APInt-like object that must:
* Have a static const max_size_in_bits equal to the number of bits in the encoding.
* be default-constructible and copy-constructible
* be constructible from a uint64_t (this is the key area the interface deviates
from APInt since this constructor does not take the bit width)
* be constructible from an APInt (this can be private)
* be convertible to uint64_t
* Support the ~, &,, ==, !=, and |= operators with other objects of the same type
* Support shift (<<, >>) with signed and unsigned integers on the RHS
* Support put (<<) to raw_ostream&
Reviewers: bogner, charukcs
Subscribers: nhaehnle, llvm-commits
Differential Revision: https://reviews.llvm.org/D52100
llvm-svn: 345056
Summary:
Replace its functionality with a TableGen InstrInfo relational
instruction mapping. Although arguably more complex than the TableGen
backend, the relational mapping is a smaller maintenance burden than a
TableGen backend.
Reviewers: aardappel, aheejin, dschuff
Subscribers: mgorny, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53307
llvm-svn: 344962
This patch adds the ability to identify instructions that are "move elimination
candidates". It also allows scheduling models to describe processor register
files that allow move elimination.
A move elimination candidate is an instruction that can be eliminated at
register renaming stage.
Each subtarget can specify which instructions are move elimination candidates
with the help of tablegen class "IsOptimizableRegisterMove" (see
llvm/Target/TargetInstrPredicate.td).
For example, on X86, BtVer2 allows both GPR and MMX/SSE moves to be eliminated.
The definition of 'IsOptimizableRegisterMove' for BtVer2 looks like this:
```
def : IsOptimizableRegisterMove<[
InstructionEquivalenceClass<[
// GPR variants.
MOV32rr, MOV64rr,
// MMX variants.
MMX_MOVQ64rr,
// SSE variants.
MOVAPSrr, MOVUPSrr,
MOVAPDrr, MOVUPDrr,
MOVDQArr, MOVDQUrr,
// AVX variants.
VMOVAPSrr, VMOVUPSrr,
VMOVAPDrr, VMOVUPDrr,
VMOVDQArr, VMOVDQUrr
], CheckNot<CheckSameRegOperand<0, 1>> >
]>;
```
Definitions of IsOptimizableRegisterMove from processor models of a same
Target are processed by the SubtargetEmitter to auto-generate a target-specific
override for each of the following predicate methods:
```
bool TargetSubtargetInfo::isOptimizableRegisterMove(const MachineInstr *MI)
const;
bool MCInstrAnalysis::isOptimizableRegisterMove(const MCInst &MI, unsigned
CPUID) const;
```
By default, those methods return false (i.e. conservatively assume that there
are no move elimination candidates).
Tablegen class RegisterFile has been extended with the following information:
- The set of register classes that allow move elimination.
- Maxium number of moves that can be eliminated every cycle.
- Whether move elimination is restricted to moves from registers that are
known to be zero.
This patch is structured in three part:
A first part (which is mostly boilerplate) adds the new
'isOptimizableRegisterMove' target hooks, and extends existing register file
descriptors in MC by introducing new fields to describe properties related to
move elimination.
A second part, uses the new tablegen constructs to describe move elimination in
the BtVer2 scheduling model.
A third part, teaches llm-mca how to query the new 'isOptimizableRegisterMove'
hook to mark instructions that are candidates for move elimination. It also
teaches class RegisterFile how to describe constraints on move elimination at
PRF granularity.
llvm-mca tests for btver2 show differences before/after this patch.
Differential Revision: https://reviews.llvm.org/D53134
llvm-svn: 344334
Summary:
The predicate function is added in InlinePatternFragments, no need to
do it here. As a result, all uses of addPredicateFn are located in
InlinePatternFragments.
Test confirmed that there are no changes to generated files when
building all (non-experimental) targets.
Change-Id: I720e42e045ca596eb0aa339fb61adf6fe71034d5
Reviewers: arsenm, rampitec, RKSimon, craig.topper, hfinkel, uweigand
Subscribers: wdng, llvm-commits
Differential Revision: https://reviews.llvm.org/D51993
llvm-svn: 343977
There are a few leftovers in rL343163 which span two lines. This commit
changes these llvm::sort(C.begin(), C.end, ...) to llvm::sort(C, ...)
llvm-svn: 343426
Summary:
By using the existing isCodeGenOnly bit in the tablegen defs, as
suggested by tlively in https://reviews.llvm.org/D51662
Tested: llvm-lit -v `find test -name WebAssembly`
Reviewers: tlively
Subscribers: dschuff, sbc100, jgravelle-google, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52373
llvm-svn: 342772
Summary:
This ensures we have the non-register version of the instruction.
The stack version of call_indirect now wants a type index argument,
so that has been added in the existing tests.
Tested:
llvm-lit -v `find test -name WebAssembly`
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51662
llvm-svn: 342753
The reason why build #25777 might have failed is because the SmallVector move
constructor is _not_ noexcept, and the stl implementation used by that buildbot
calls _VSTD::move_if_noexcept() (according to the backtrace).
OpcodeInfo has a default move constructor, and the copy constructor is deleted.
However, as far as I can see, SmallVector doesn't declare a noexcept move
constructor. So, what I believe it is happening here is that,
_VSTD::move_if_noexcept() returns an lvalue reference and not an rvalue
reference.
This eventually triggers a copy that fails to compile.
Hopefully, using a std::vector instead of SmallVector (as it was originally
suggested by Simon in the code review) should be enough to unbreak the buildbot.
llvm-svn: 342561
This patch adds the ability for processor models to describe dependency breaking
instructions.
Different processors may specify a different set of dependency-breaking
instructions.
That means, we cannot assume that all processors of the same target would use
the same rules to classify dependency breaking instructions.
The main goal of this patch is to provide the means to describe dependency
breaking instructions directly via tablegen, and have the following
TargetSubtargetInfo hooks redefined in overrides by tabegen'd
XXXGenSubtargetInfo classes (here, XXX is a Target name).
```
virtual bool isZeroIdiom(const MachineInstr *MI, APInt &Mask) const {
return false;
}
virtual bool isDependencyBreaking(const MachineInstr *MI, APInt &Mask) const {
return isZeroIdiom(MI);
}
```
An instruction MI is a dependency-breaking instruction if a call to method
isDependencyBreaking(MI) on the STI (TargetSubtargetInfo object) evaluates to
true. Similarly, an instruction MI is a special case of zero-idiom dependency
breaking instruction if a call to STI.isZeroIdiom(MI) returns true.
The extra APInt is used for those targets that may want to select which machine
operands have their dependency broken (see comments in code).
Note that by default, subtargets don't know about the existence of
dependency-breaking. In the absence of external information, those method calls
would always return false.
A new tablegen class named STIPredicate has been added by this patch to let
processor models classify instructions that have properties in common. The idea
is that, a MCInstrPredicate definition can be used to "generate" an instruction
equivalence class, with the idea that instructions of a same class all have a
property in common.
STIPredicate definitions are essentially a collection of instruction equivalence
classes.
Also, different processor models can specify a different variant of the same
STIPredicate with different rules (i.e. predicates) to classify instructions.
Tablegen backends (in this particular case, the SubtargetEmitter) will be able
to process STIPredicate definitions, and automatically generate functions in
XXXGenSubtargetInfo.
This patch introduces two special kind of STIPredicate classes named
IsZeroIdiomFunction and IsDepBreakingFunction in tablegen. It also adds a
definition for those in the BtVer2 scheduling model only.
This patch supersedes the one committed at r338372 (phabricator review: D49310).
The main advantages are:
- We can describe subtarget predicates via tablegen using STIPredicates.
- We can describe zero-idioms / dep-breaking instructions directly via
tablegen in the scheduling models.
In future, the STIPredicates framework can be used for solving other problems.
Examples of future developments are:
- Teach how to identify optimizable register-register moves
- Teach how to identify slow LEA instructions (each subtarget defining its own
concept of "slow" LEA).
- Teach how to identify instructions that have undocumented false dependencies
on the output registers on some processors only.
It is also (in my opinion) an elegant way to expose knowledge to both external
tools like llvm-mca, and codegen passes.
For example, machine schedulers in LLVM could reuse that information when
internally constructing the data dependency graph for a code region.
This new design feature is also an "opt-in" feature. Processor models don't have
to use the new STIPredicates. It has all been designed to be as unintrusive as
possible.
Differential Revision: https://reviews.llvm.org/D52174
llvm-svn: 342555
Further extension to D51035, this patch avoids all repeated predicates[] matching by caching as it collects the patterns that have multiple variants.
Saves around 25secs in debug builds of x86 -gen-dag-isel.
Differential Revision: https://reviews.llvm.org/D51839
llvm-svn: 342467
Summary:
Now uses the StackBased bit from the tablegen defs to identify
stack instructions (and ignore register based or non-wasm instructions).
Also changed how we store operands, since we now have up to 16 of them
per instruction. To not cause static data bloat, these are compressed
into a tiny table.
+ a few other cleanups.
Tested:
- MCTest
- llvm-lit -v `find test -name WebAssembly`
Reviewers: dschuff, jgravelle-google, sunfish, tlively
Subscribers: sbc100, aheejin, llvm-commits
Differential Revision: https://reviews.llvm.org/D51320
llvm-svn: 341081
Summary:
Add comments to help readers avoid having to read tablegen backends to
understand the code. Also remove unecessary breaks from the output.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51371
llvm-svn: 340864
CodeGenDAGPatterns::GenerateVariants is a costly function in many tblgen commands (33.87% of the total runtime of x86 -gen-dag-isel), and due to the O(N^2) nature of the function, there are a high number of repeated comparisons of the pattern's vector<Predicate>.
This initial patch at least avoids repeating these comparisons for every Variant in a pattern. I began investigating caching all the matches before entering the loop but hit issues with how best to store the data and how to update the cache as patterns were added.
Saves around 15secs in debug builds of x86 -gen-dag-isel.
Differential Revision: https://reviews.llvm.org/D51035
llvm-svn: 340837
Summary:
The new stackification backend generates the giant switch statement
used to translate instructions to their stackified forms. I did this
because it was more interesting than adding all the different vector
versions of the various SIMD instructions to the switch statment
manually.
Reviewers: aardappel, aheejin, dschuff
Subscribers: mgorny, sbc100, jgravelle-google, sunfish, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D51318
llvm-svn: 340781
Summary:
So far, `isReturn` property is used to mean both a return instruction
from a functon and the end of an EH scope, a scope that starts with a EH
scope entry BB and ends with a catchret or a cleanupret instruction.
Because WinEH uses funclets, all EH-scope-ending instructions are also
real return instruction from a function. But for wasm, they only serve
as the end marker of an EH scope but not a return instruction that
exits a function. This mismatch caused incorrect prolog and epilog
generation in wasm EH scopes. This patch fixes this.
This patch is in the same vein with rL333045, which splits
`MachineBasicBlock::isEHFuncletEntry` into `isEHFuncletEntry` and
`isEHScopeEntry`.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D50653
llvm-svn: 340325
We were just caching the MVT set of legal types, then every call creating a new TypeSetByHwMode with it and passing it back on the stack. There's no need to do this - we can create and cache the whole TypeSetByHwMode once and return a const reference to it each time.
Additionally, TypeInfer::expandOverloads wasn't making use of the fact that the cache just contains a default mode containing all the types.
Saves up to 30secs in debug builds of x86 -gen-dag-isel.
Differential Revision: https://reviews.llvm.org/D50903
llvm-svn: 340042
This operator is called a great deal, by checking for the cheap isSimple equality cases first (a common occurrence) we can improve performance as we avoid a lot of std::map find/iteration in hasDefault.
isSimple also means that a default value is present, so we can avoid some hasDefault calls.
This also avoids a rather dodgy piece of logic that was checking for isSimple() && !VTS.isSimple() but not the inverse - it now uses the general hasDefault mode comparison test instead.
Saves around 15secs in debug builds of x86 -gen-dag-isel.
Differential Revision: https://reviews.llvm.org/D50841
llvm-svn: 339890
I noticed this during profiling of tablegen (PR28222) that we were calling Child->getType(0) which creates a ValueTypeByHwMode on the fly from the requested internal TypeSetByHwMode type and returns it by value, we then treat it as a TypeSetByHwMode reference which involves constructing a new TypeSetByHwMode on the stack with a large amount of std::map iterating/copying all along the way.
I am not an expert on tablegen, but AFAICT this is all unnecessary and we should be calling Child->getExtType(0) which returns the original TypeSetByHwMode by reference.
This gives me a 90sec reduction in msvc debug builds of x86 -gen-dag-isel.
Differential Revision: https://reviews.llvm.org/D50789
llvm-svn: 339812
This patch removes redundant template argument `TargetName` from TIIPredicate.
Tablegen can always infer the target name from the context. So we don't need to
force users of TIIPredicate to always specify it.
This allows us to better modularize the tablegen class hierarchy for the
so-called "function predicates". class FunctionPredicateBase has been added; it
is currently used as a building block for TIIPredicates. However, I plan to
reuse that class to model other function predicate classes too (i.e. not just
TIIPredicates). For example, this can be a first step towards implementing
proper support for dependency breaking instructions in tablegen.
This patch also adds a verification step on TIIPredicates in tablegen.
We cannot have multiple TIIPredicates with the same name. Otherwise, this will
cause build errors later on, when tablegen'd .inc files are included by cpp
files and then compiled.
Differential Revision: https://reviews.llvm.org/D50708
llvm-svn: 339706
The behavior in 64-bit mode is different between Intel and AMD CPUs. Intel ignores the 0x66 prefix. AMD does not. objump doesn't ignore the 0x66 prefix. Since LLVM aims to match objdump behavior, we should do the same.
While I was trying to fix this I had change brtarget16/32 to use ENCODING_IW/ID instead of ENCODING_Iv to get the 0x66+REX.W case to act sort of sanely. It's still wrong, but that's a problem for another day.
The change in encoding exposed the fact that 16-bit mode disassembly of relative jumps was creating JMP_4 with a 2 byte immediate. It should have been JMP_2. From just printing you can't tell the difference, but if you dumped the encoding it wouldn't have matched what we started with.
While fixing that, it exposed that jo/jno opcodes were missing from the switch that this patch deleted and there were no test cases for them.
Fixes PR38537.
llvm-svn: 339622
This is a follow-up of r339552.
As pointed out by Craig in D50566, we don't need a formatted_raw_ostream to
indent strings. We can use instead raw_ostream::indent().
Internally, class PredicateExpander already keeps track of the current
indentation level. Also, the grammar for predicates is well parenthesized, and
therefore we don't need to use a formatted_raw_ostream to continuously track the
column number. Instead we can safely replace all the uses of
formatted_raw_ostream::PadToColumn() with uses of raw_ostream::indent().
By replacing formatted_raw_ostream with a simpler raw_ostream, we also avoid the
implicit check on the newline character on every print to stream.
No functional change intended.
llvm-svn: 339577
This patch refactors the logic that expands predicates of a variant scheduling
class.
The idea is to improve the readability of the auto-generated code by removing
redundant parentheses around predicate expressions, and by removing redundant
if(true) statements.
This patch replaces the definition of NoSchedPred in TargetSchedule.td with an
instance of MCSchedPredicate. The new definition is sematically equivalent to
the previous one. The main difference is that now SubtargetEmitter knows that it
represents predicate "true".
Before this patch, we always generated an if (true) for the default transition
of a variant scheduling class.
Example (taken from AArch64GenSubtargetInfo.inc) :
```
if (SchedModel->getProcessorID() == 3) { // CycloneModel
if ((TII->isScaledAddr(*MI)))
return 927; // (WriteIS_WriteLD)_ReadBaseRS
if ((true))
return 928; // WriteLD_ReadDefault
}
```
Extra parentheses were also generated around the predicate expressions.
With this patch, we get the following auto-generated checks:
```
if (SchedModel->getProcessorID() == 3) { // CycloneModel
if (TII->isScaledAddr(*MI))
return 927; // (WriteIS_WriteLD)_ReadBaseRS
return 928; // WriteLD_ReadDefault
}
```
The new auto-generated code behaves exactly the same as before. So, technically
this is a non functional change.
Differential revision: https://reviews.llvm.org/D50566
llvm-svn: 339552
Part of the logic has been moved to helper functions to (hopefully) improve
readability.
Added a few code comments to better describe how the algorithm works.
No functional change intended.
llvm-svn: 339421
This patch introduces tablegen class MCStatement.
Currently, an MCStatement can be either a return statement, or a switch
statement.
```
MCStatement:
MCReturnStatement
MCOpcodeSwitchStatement
```
A MCReturnStatement expands to a return statement, and the boolean expression
associated with the return statement is described by a MCInstPredicate.
An MCOpcodeSwitchStatement is a switch statement where the condition is a check
on the machine opcode. It allows the definition of multiple checks, as well as a
default case. More details on the grammar implemented by these two new
constructs can be found in the diff for TargetInstrPredicates.td.
This patch makes it easier to read the body of auto-generated TargetInstrInfo
predicates.
In future, I plan to reuse/extend the MCStatement grammar to describe more
complex target hooks. For now, this is just a first step (mostly a minor
cosmetic change to polish the new predicates framework).
Differential Revision: https://reviews.llvm.org/D50457
llvm-svn: 339352
Summary:
The interface to get size and spill size of a register
was moved from MCRegisterInfo to TargetRegisterInfo over
a year ago. Afaik the old interface has bee around
to give out-of-tree targets a chance to adapt to the
new interface.
One problem with the old MCRegisterClass::PhysRegSize was that
it represented the size of a register as "size in bits" / 8.
So a register had to be a multiple of eight bits wide for the
size to be correct (and the byte size for the target needed to
be eight bits).
Reviewers: kparzysz, qcolombet
Reviewed By: kparzysz
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D47199
llvm-svn: 339350
Summary:
This particular map is hardly ever queried and has a phased usage pattern (insert,
iterate, query, insert, iterate) so it's a good candidate for a sorted vector and
std::lower_bound.
This significantly reduces the run time of runTargetDesc() in some circumstances.
One llvm-tblgen invocation in my build improves the time spent in runTargetDesc()
from 9.86s down to 0.80s (~92%) without changing the output. The same invocation
also has 2GB less allocation churn.
Reviewers: bogner, rtereshin, aditya_nandakumar, volkan
Reviewed By: rtereshin
Subscribers: mgrang, dexonsmith, llvm-commits
Differential Revision: https://reviews.llvm.org/D50272
llvm-svn: 339208
The DAG combiner logic to simplify AND masks in shift counts is invalid.
While it is true that the SystemZ shift instructions ignore all but the
low 6 bits of the shift count, it is still invalid to simplify the AND
masks while the DAG still uses the standard shift operators (which are
*not* defined to match the SystemZ instruction behavior).
Instead, this patch performs equivalent operations during instruction
selection. For completely removing the AND, this now happens via
additional DAG match patterns implemented by a multi-alternative
PatFrags. For simplifying a 32-bit AND to a 16-bit AND, the existing DAG
patterns were already mostly OK, they just needed an output XForm to
actually truncate the immediate value.
Unfortunately, the latter change also exposed a bug in TableGen: it
seems XForms are currently only handled correctly for direct operands of
the outermost operation node. This patch also fixes that bug by simply
recurring through the whole pattern. This should be NFC for all other
targets.
Differential Revision: https://reviews.llvm.org/D50096
llvm-svn: 338521
Summary:
The VS compiler (on Windows) has a bug which results in fieldFromInstruction being optimized out in some circumstances. This only happens in *release no debug info* builds that have assertions *turned off* - in all other situations the function is not inlined, so the functionality is correct. All of the bots have assertions turned on, so this path is not regularly tested. The workaround is to not inline the function on Windows - if the bug is fixed in a later release of the VS compiler, the noinline specification can be removed.
The test that consistently reproduces this is Lanai v11.txt test.
Reviewers: asmith, labath, zturner
Subscribers: dblaikie, stella.stamenova, aprantl, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D49753
llvm-svn: 337942
Function `expandCheckImmOperand` should always check if the input machine
instruction is passed by reference before calling method `getOperand()` on it.
Found while working on a patch that relies on `expandCheckImmOperand` to expand
a scheduling predicate.
llvm-svn: 337294
Currently, any attempt to define a PatFrag involving any floating-point
only (or vector only) node causes a hard assertion failure in TableGen
if the current target does not have any floating-point (or vector)
types.
This is annoying if you want to provide convenience fragments in common
code (e.g. include/llvm/Target/TargetSelectionDAG.td) that is parsed on
all platforms, including those that miss such types.
But really, there's no reason not accept this when parsing the fragment
-- of course it would be an error for such a target to actually *use*
such a fragment anywhere, but as long as it doesn't, I think TableGen
shouldn't error out.
The immediate cause of the assertion failure is the test inside the
ValidateOnExit destructor. This patch simply disables that check while
infering types during parsing of pattern fragments (only).
Reviewed By: hfinkel, kparzysz
Differential Revision: https://reviews.llvm.org/D48887
llvm-svn: 337023
isSubsetOf() could be very slow if the hierarchy of the RegisterClasses
of the target is very complicated.
This is mainly caused by the fact that isSubset() is called
multiple times over the same SuperClass of a register class
if this ends up being the super class of a register class
from multiple paths.
Differential Revision: https://reviews.llvm.org/D49124
llvm-svn: 337020
This patch adds support for AArch64 to cfi-verify.
This required three changes to cfi-verify. First, it generalizes checking if an instruction is a trap by adding a new isTrap flag to TableGen (and defining it for x86 and AArch64). Second, the code that ensures that the operand register is not clobbered between the CFI check and the indirect call needs to allow a single dereference (in x86 this happens as part of the jump instruction). Third, we needed to ensure that return instructions are not counted as indirect branches. Technically, returns are indirect branches and can be covered by CFI, but LLVM's forward-edge CFI does not protect them, and x86 does not consider them, so we keep that behavior.
In addition, we had to improve AArch64's code to evaluate the branch target of a MCInst to handle calls where the destination is not the first operand (which it often is not).
Differential Revision: https://reviews.llvm.org/D48836
llvm-svn: 337007
A TableGen instruction record usually contains a DAG pattern that will
describe the SelectionDAG operation that can be implemented by this
instruction. However, there will be cases where several different DAG
patterns can all be implemented by the same instruction. The way to
represent this today is to write additional patterns in the Pattern
(or usually Pat) class that map those extra DAG patterns to the
instruction. This usually also works fine.
However, I've noticed cases where the current setup seems to require
quite a bit of extra (and duplicated) text in the target .td files.
For example, in the SystemZ back-end, there are quite a number of
instructions that can implement an "add-with-overflow" operation.
The same instructions also need to be used to implement just plain
addition (simply ignoring the extra overflow output). The current
solution requires creating extra Pat pattern for every instruction,
duplicating the information about which particular add operands
map best to which particular instruction.
This patch enhances TableGen to support a new PatFrags class, which
can be used to encapsulate multiple alternative patterns that may
all match to the same instruction. It operates the same way as the
existing PatFrag class, except that it accepts a list of DAG patterns
to match instead of just a single one. As an example, we can now define
a PatFrags to match either an "add-with-overflow" or a regular add
operation:
def z_sadd : PatFrags<(ops node:$src1, node:$src2),
[(z_saddo node:$src1, node:$src2),
(add node:$src1, node:$src2)]>;
and then use this in the add instruction pattern:
defm AR : BinaryRRAndK<"ar", 0x1A, 0xB9F8, z_sadd, GR32, GR32>;
These SystemZ target changes are implemented here as well.
Note that PatFrag is now defined as a subclass of PatFrags, which
means that some users of internals of PatFrag need to be updated.
(E.g. instead of using PatFrag.Fragment you now need to use
!head(PatFrag.Fragments).)
The implementation is based on the following main ideas:
- InlinePatternFragments may now replace each original pattern
with several result patterns, not just one.
- parseInstructionPattern delays calling InlinePatternFragments
and InferAllTypes. Instead, it extracts a single DAG match
pattern from the main instruction pattern.
- Processing of the DAG match pattern part of the main instruction
pattern now shares most code with processing match patterns from
the Pattern class.
- Direct use of main instruction patterns in InferFromPattern and
EmitResultInstructionAsOperand is removed; everything now operates
solely on DAG match patterns.
Reviewed by: hfinkel
Differential Revision: https://reviews.llvm.org/D48545
llvm-svn: 336999
The aim of this backend is to output everything TableGen knows about
the record set, similarly to the default -print-records backend. But
where -print-records produces output in TableGen's input syntax
(convenient for humans to read), this backend produces it as
structured JSON data, which is convenient for loading into standard
scripting languages such as Python, in order to extract information
from the data set in an automated way.
The output data contains a JSON representation of the variable
definitions in output 'def' records, and a few pieces of metadata such
as which of those definitions are tagged with the 'field' prefix and
which defs are derived from which classes. It doesn't dump out
absolutely every piece of knowledge it _could_ produce, such as type
information and complicated arithmetic operator nodes in abstract
superclasses; the main aim is to allow consumers of this JSON dump to
essentially act as new backends, and backends don't generally need to
depend on that kind of data.
The new backend is implemented as an EmitJSON() function similar to
all of llvm-tblgen's other EmitFoo functions, except that it lives in
lib/TableGen instead of utils/TableGen on the basis that I'm expecting
to add it to clang-tblgen too in a future patch.
To test it, I've written a Python script that loads the JSON output
and tests properties of it based on comments in the .td source - more
or less like FileCheck, except that the CHECK: lines have Python
expressions after them instead of textual pattern matches.
Reviewers: nhaehnle
Reviewed By: nhaehnle
Subscribers: arichardson, labath, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D46054
llvm-svn: 336771
The vast number of added instructions for SVE causes TableGen to fail with an assertion:
Assertion `Delta < 65536U && "disassembler decoding table too large!"'
This patch increases the number of supported decoder fix-ups.
Reviewers: dmgreen, stoklund, petpav01
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D48937
llvm-svn: 336334
Add registers still missing after r328016 (D43353):
- for bits 15-8 of SI, DI, BP, SP (*H), and R8-R15 (*BH),
- for bits 31-16 of R8-R15 (*WH).
Thanks to Craig Topper for pointing it out.
llvm-svn: 336134
Implements PR34259
Intrinsics.h is a very popular header. Most LLVM TUs care about things
like dbg_value, but they don't care how they are implemented. After I
split these out, IntrinsicImpl.inc is 1.7 MB, so this saves each LLVM TU
from scanning 1.7 MB of source that gets pre-processed away.
It also means we can modify intrinsic properties without triggering a
full rebuild, but that's probably less of a win.
I think the next best thing to do would be to split out the target
intrinsics into their own header. Very, very few TUs care about
target-specific intrinsics. It's very hard to split up the target
independent intrinsics like llvm.expect, assume, and dbg.value, though.
llvm-svn: 335407
Summary:
This is essentially a rewrite of the backend which introduces TableGen
base classes GenericEnum, GenericTable, and SearchIndex. They allow
generating custom enums and tables with lookup functions using
separately defined records as the underlying database.
Also added as part of this change:
- Lookup functions may use indices composed of multiple fields.
- Instruction fields are supported similar to Intrinsic fields.
- When the lookup key has contiguous numeric values, the lookup
function will directly index into the table instead of using a binary
search.
The existing SearchableTable functionality is internally mapped to the
new primitives.
Change-Id: I444f3490fa1dbfb262d7286a1660a2c4308e9932
Reviewers: arsenm, tra, t.p.northover
Subscribers: wdng, llvm-commits
Differential Revision: https://reviews.llvm.org/D48013
llvm-svn: 335225
This adds an EVEX2VEXOverride string to the X86 instruction class in X86InstrFormats.td. If this field is set it will add manual entry in the EVEX->VEX tables that doesn't check the encoding information.
Then use this mechanism to map VMOVDU/A8/16, 128-bit VALIGN, and VPSHUFF/I instructions to VEX instructions.
Finally, remove the manual table from the emitter.
This has the bonus of fully sorting the autogenerated EVEX->VEX tables by their EVEX instruction enum value. We may be able to use this to do a binary search for the conversion and get rid of the need to create a DenseMap.
llvm-svn: 335018
EVEX makes heavy use of the VEX.W bit to indicate 64-bit element vs 32-bit elements. Many of the VEX instructions were split into 2 versions with different masking granularity.
The EVEX->VEX table generate can collapse the two versions if the VEX version uses is tagged as VEX_WIG. But if the VEX version is instead marked VEX.W==0 we can't combine them because we don't know if there is also a VEX version with VEX.W==1.
This patch adds a new VEX_W1X tag that indicates the EVEX instruction encodes with VEX.W==1, but is safe to convert to a VEX instruction with VEX.W==0.
This allows us to remove a bunch of manual EVEX->VEX table entries. We may want to look into splitting up the VEX_WPrefix field which would simplify the disassembler.
llvm-svn: 335017
Rather than having an exclusion list in tablegen sources, add a flag to the X86 instruction records that can be used to suppress checking for convertibility.
llvm-svn: 334971
Allow a tied operand of a different operand class in InstAliases,
so that the operand can be printed (and added to the MC instruction)
as the appropriate register. For example, 'GPR64as32', which would
be printed/parsed as a 32bit register and should match a tied 64bit
register operand, where the former is a sub-register of the latter.
This patch also generalizes the constraint checking to an overrideable
method in MCTargetAsmParser, so that target asmparsers can specify
whether a given operand satisfies the tied register constraint.
Reviewers: olista01, rengolin, fhahn, SjoerdMeijer, samparker, dsanders, craig.topper
Reviewed By: fhahn
Differential Revision: https://reviews.llvm.org/D47714
llvm-svn: 334942
Unlike CodeGenInstruction, CodeGenInstAlias was flatting asm strings in its constructor. For instructions it was the users responsibility to flatten the string.
AsmMatcherEmitter didn't know this and treated them the same. This caused double flattening of InstAliases. This is mostly harmless unless the desired assembly string contains curly braces. The second flattening wouldn't know to ignore these and would remove the curly braces. And for variant 1 it would remove the contents of them as well.
To mitigate this, this patch makes removes the flattening from the CodeGenIntAlias constructor and modifies AsmWriterEmitter to account for the flattening not having been done.
llvm-svn: 334919
So far, we've only handled special cases of PatFrag like ImmLeaf. This patch
adds support for the remaining cases using similar mechanisms.
Like most C++ code from SelectionDAG, GISel and DAGISel expect to operate on
different types and representations and as such the code is not compatible
between the two. It's therefore necessary to add an alternative implementation
in the GISelPredicateCode field.
The target test for this feature could easily be done with IntImmLeaf and this
would save on a little boilerplate. The reason I've chosen to implement this
using PatFrag.GISelPredicateCode and not IntImmLeaf is because I was unable to
find a rule that was blocked solely by lack of support for PatFrag predicates. I
found that the ones I investigated as being likely candidates for the test
were further blocked by other things.
llvm-svn: 334871
The return value of TreePatternNode::getChild is never null. This patch also
updates various places that use return values of getChild to also use
references. Those changes were suggested post-commit for D47463.
llvm-svn: 334764
Summary:
For targets I'm not familiar with, I've automatically made the "default to 1 for each resource" behaviour explicit in the td files.
For more obvious cases, I've ventured a fix.
Some notes:
- Exynos is especially fishy.
- AArch64SchedThunderX2T99.td had some truncated entries. If I understand correctly, the person who wrote that interpreted the ResourceCycle as a range. I made the decision to use the upper/lower bound for consistency with the 'Latency' value. I'm sure there is a better choice.
- The change to X86ScheduleBtVer2.td is an NFC, it just makes values more explicit.
Also see PR37310.
Reviewers: RKSimon, craig.topper, javed.absar
Subscribers: kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D46356
llvm-svn: 334586
Previously we were whitelisting in instructions based on their SchedRW value. With the masked store instructions explicitly removed via NotMemoryFoldable, we don't seem to need this check anymore.
llvm-svn: 334563
Andrea Di Biagio