In Vulkan, the signedness of the accesses to images has to match the
signedness of the backing image.
See
https://docs.vulkan.org/spec/latest/chapters/textures.html#textures-input,
where it says the behaviour is undefined if
> the signedness of any read or sample operation does not match the
signedness of the image’s format.
Users who define say an `RWBuffer<int>` will create a Vulkan image with
a signed integer format. So the HLSL that is generated must match that
expecation.
The solution we use is to generate a `spirv.SignedImage` target type for
signed integer instead of `spirv.Image`. The two types are otherwise the
same.
The backend will add the `signExtend` image operand to access to the
image to ensure the image is access as a signed image.
Fixes#144580
The SPIR-V backend does not have access to the original name of a
resource in the source, so it tries to create a name. This leads to some
problems with reflection.
That is why start to pass the name of the resource from Clang to the
SPIR-V backend.
Fixes#138533
The asan failure was fixed by #138695, but another failure was
introduced in the meantime. The cause for the other failure has been
fixed. I will reapply the two PRs.
Reapply "[SPIRV] Add explicit layout (#135789)"
This reverts commit 0fb5720b4bf461d4d51ee85a8a6f4ea4f6fb4966.
Reapply "[SPIRV] Fix asan failure (#138695)"
This reverts commit df90ab96fb5a10df88fcfe6b0e8e63781ca24eca.
Adds code to add offset decorations when needed. This could cause a
type mismatch for memory instructions. We add code to fix up OpLoad
instructions, so that we could get some tests. Other memory operations
will be handled in another PR.
Part of https://github.com/llvm/llvm-project/issues/134119.
Adds code to expand the `llvm.spv.resource.handlefrombinding` and
`llvm.spv.resource.getpointer` when the resource type is
`spirv.VulkanBuffer`.
It gets expanded as a storage buffer or uniform buffer denpending on the
storage class used.
This is implementing part of
https://github.com/llvm/wg-hlsl/blob/main/proposals/0018-spirv-resource-representation.md.
This PR is to thoroughly rework duplicate tracker implementation and
tracking of IR entities and types. These are legacy parts of the project
resulting in an extremely bloated intermediate representation and
computational delays due to inefficient data flow and structure choices.
Main results of the rework:
1) Improved compile-time performance. The reference binary LLVM IR used
to measure speed gains in
https://github.com/llvm/llvm-project/pull/120415 shows ~x5 speed up also
after this PR. The timing before this PR is ~42s and after this PR it's
~7.5s. In total this PR and the previous overhaul of the module analysis
in https://github.com/llvm/llvm-project/pull/120415 results in ~x25
speed improvement.
```
$ time llc -O0 -mtriple=spirv64v1.6-unknown-unknown _group_barrier_phi.bc -o 1 --filetype=obj
real 0m7.545s
user 0m6.685s
sys 0m0.859s
```
2) Less bloated intermediate representation of internal translation
steps. Elimination of `spv_track_constant` intrinsic usage for scalar
constants, rework of `spv_assign_name`, removal of the gMIR `GET_XXX`
pseudo code and a smaller number of generated `ASSIGN_TYPE` pseudo codes
substantially decrease volume of data generated during translation.
3) Simpler code and easier maintenance. The duplicate tracker
implementation is simplified, as well as other features.
4) Numerous fixes of issues and logical flaws in different passes. The
main achievement is rework of the duplicate tracker itself that had
never guaranteed a correct caching of LLVM IR entities, rarely and
randomly returning stale/incorrect records (like, remove an instruction
from gMIR but still refer to it). Other fixes comprise consistent
generation of OpConstantNull, assigning types to newly created
registers, creation of integer/bool types, and other minor fixes.
5) Numerous fixes of LIT tests: mainly CHECK-DAG to properly reflect
SPIR-V spec guarantees, `{{$}}` at the end of constants to avoid
matching of substrings, and XFAILS for `SPV_INTEL_long_composites` test
cases, because the feature is not completed in full yet and doesn't
generate a requested by the extension sequence of instructions.
6) New test cases are added.
Spec can be found here https://github.com/intel/llvm/pull/15225
TODO for future patches:
- During spec review need to decide whether only FunctionCall or Atomic
instructions can be decorated and if not - move the code around adding
handling for other instructions;
- Handle optional string metadata;
- Handle LLVM atomic instructions;
- Handle SPIR-V friendly atomic calls returning via sret argument.
Signed-off-by: Sidorov, Dmitry <dmitry.sidorov@intel.com>
OpenCL is allowed to cast pointers, meaning they can resolve some type
mismatches this way. In logical SPIR-V, those are restricted. This new
pass legalizes such pointer cast when targeting logical SPIR-V.
For now, this pass supports 3 cases we witnessed:
- loading a vec3 from a vec4*.
- loading a scalar from a vec*.
- loading the 1st element of an array.
---------
Co-authored-by: Steven Perron <stevenperron@google.com>
The SPIR-V Backend uses the same set of utility functions, mostly though
not entirely from SPIRVGlobalRegistry, to generate gMIR and SPIR-V
opcodes, depending on the current stage of translation. This is
controlled by an explicit EmitIR flag rather than the current
translation pass, and there are legacy pieces of code where the EmitIR
flag is declared so that it has a default true value, allowing using
utility functions without explicitly declaring their intent to work
either in gMIR or in SPIR-V part of the lowering process.
While it may be ok to leave this default EmitIR flag as is in generation
of scalar integer/float types, as we don't expect to see any dependent
opcodes derived from such OpTypeXXX instructions, using of EmitIR by
default in aggregation types is a source of hidden logical flaws and
actual issues.
This PR provides a partial fix to the problem by removing default status
of EmitIR, requiring a user call site to explicitly announce its intent
to generate gMIR or SPIR-V code, fixes several cases of misuse of
EmitIR, and, the most important, fixes a nasty logical error that breaks
passing of actually asked EmitIR value by the default value in the
middle of the chain of calls, in the `findSPIRVType` call. The latter
error was a source of issues in the post-instruction selection pass that
has been getting gMIR code where SPIR-V was explicitly requested due to
overloaded with default parameters internal API in SPIRVGlobalRegistry
(most notably, `findSPIRVType`).
The code pattern that clang will generate for HLSL has changed from the
original plan. This allows the SPIR-V backend to generate code for the
current code generation.
It looks for patterns of the form:
```
%1 = @llvm.spv.resource.handlefrombinding
%2 = @llvm.spv.resource.getpointer(%1, index)
load/store %2
```
These three llvm-ir instruction are treated as a single unit that will
1. Generate or find the global variable identified by the call to
`resource.handlefrombinding`.
2. Generate an OpLoad of the variable to get the handle to the image.
3. Generate an OpImageRead or OpImageWrite using that handle with the
given index.
This will generate the OpLoad in the same BB as the read/write.
Note: Now that `resource.handlefrombinding` is not processed on its own,
many existing tests had to be removed. We do not have intrinsics that
are able to use handles to sampled images, input attachments, etc., so
we cannot generate the load of the handle. These tests are removed for
now, and will be added when those resource types are fully implemented.
This PR is to address legacy issues with module analysis that currently
uses a complicated and not so efficient approach to trace dependencies
between SPIR-V id's via a duplicate tracker data structures and an
explicitly built dependency graph. Even a quick performance check
without any specialized benchmarks points to this part of the
implementation as a biggest bottleneck.
This PR specifically:
* eliminates a need to build a dependency graph as a data structure,
* updates the test suite (mainly, by fixing incorrect CHECK's referring
to a hardcoded order of definitions, contradicting the spec requirement
to allow certain definitions to go "in any order", see
https://registry.khronos.org/SPIR-V/specs/unified1/SPIRV.html#_logical_layout_of_a_module),
* improves function pointers implementation so that it now passes
EXPENSIVE_CHECKS (thus removing 3 XFAIL's in the test suite).
As a quick sanity check of whether goals of the PR are achieved, we can
measure time of translation for any big LLVM IR. While testing the PR in
the local development environment, improvements of the x5 order have
been observed.
For example, the SYCL test case "group barrier" that is a ~1Mb binary IR
input shows the following values of the naive performance metric that we
can nevertheless apply here to roughly estimate effects of the PR.
before the PR:
```
$ time llc -O0 -mtriple=spirv64v1.6-unknown-unknown _group_barrier_phi.bc -o 1 --filetype=obj
real 3m33.241s
user 3m14.688s
sys 0m18.530s
```
after the PR
```
$ time llc -O0 -mtriple=spirv64v1.6-unknown-unknown _group_barrier_phi.bc -o 1 --filetype=obj
real 0m42.031s
user 0m38.834s
sys 0m3.193s
```
Next work should probably address Duplicate Tracker further, as it needs
analysis now from the perspective of what parts of it are not necessary
now, after changing the approach to implementation of the module
analysis step.
This PR fixes https://github.com/llvm/llvm-project/issues/120078 and
improves/simplifies parsing of demangled function name that aims to
detect a tip for floating point decorations. The latter improvement
fixes also a complaint from `LLVM_USE_SANITIZER=Address`.
Goals of the PR are:
* to ensure that correct types are applied to virtual registers which
were used as return values in call lowering. A reproducer is attached as
a new test case, before the PR it fails because spirv-val considers
output invalid due to wrong result/operand types in OpPhi's;
* improve type inference by speeding up postprocessing of types: by
limiting iterations by checking what remains to process, and processing
each instruction just once for any number of operands with uncomplete
types;
* improve type inference by more accurate work with uncomplete types
(pass uncomplete property to dependent operands, ensure consistency of
uncomplete-types data structure);
* change processing order and add traversing of PHI nodes when type
inference apply instructions results to specify/update/cast operands
type (fixes an issue with OpPhi's result type mismatch with operand
types).
This PR is to solve several intertwined issues with type inference while
adding support for builtins for OpIAddCarry and OpISubBorrow:
* OpIAddCarry and OpISubBorrow generation in a way of supporting SPIR-V
friendly builtins `__spirv_...` -- introduces a new element to account
for, namely, `ptr sret (%struct) %0` argument that is a place to put a
result of the instruction;
* fix early definition of SPIR-V types during call lowering -- namely,
the goal of the PR is to ensure that correct types are applied to
virtual registers which were used as arguments in call lowering and so
caused early definition of SPIR-V types; reproducers are attached as a
new test cases;
* improve parsing of builtin names (e.g., understand a name of a kind
`"anon<int, int> __spirv_IAddCarry<int, int>(int, int)"` that was
incorrectly parsed as `anon` before the PR);
* improve type inference and fix access to erased from parent after
visit instructions -- before the PR visiting of instructions in
emitintrinsics pass replaced old alloca's, bitcast's, etc. instructions
with a newly generated internal SPIR-V intrinsics and after erasing old
instructions there were still references to them in a postprocessing
working list, while records for newly deduced pointee types were lost;
this PR fixes the issue by adding as consistent wrt. internal data
structures action `SPIRVEmitIntrinsics::replaceAllUsesWith()` that fixes
above mentioned problems;
* LLVM IR add/sub instructions result in logical SPIR-V instructions
when applied to bool type;
* fix validation of pointer types for frexp and lgamma_r,
* fix hardcoded reference to AS0 as a Function storage class in
lib/Target/SPIRV/SPIRVBuiltins.cpp -- now it's
`storageClassToAddressSpace(SPIRV::StorageClass::Function)`,
* re-use the same OpTypeStruct for two identical references to struct's
in arithmetic with overflow instructions.
This commit adds an intrinsic that will read from an image buffer. We
chose to match the name of the DXIL intrinsic for simplicity in clang.
We cannot reuse the existing openCL readimage function because that is
not a reserved name in HLSL.
I considered trying to refactor generateReadImageInst, so that we could
share code between the two implementations. However, most of the code in
generateReadImageInst is concerned with trying to figure out which type
of image read is being done. Once we factor out the code that will be
common, then we end up with just a single call to the MIRBuilder being
common.
Implement the intrinsic `llvm.spv.handle.fromBinding`, which returns the
handle for a global resource. This involves creating a global variable
that matches the return-type, set, and binding in the call, and
returning the handle to that resource.
This commit implements the scalar version. It does not handle arrays of
resources yet. It also does not handle storage buffers yet. We do not
have the type for the storage buffers designed yet.
Part of #81036
This PR introduces changes into processing of internal/service data in
SPIRV Backend so that Duplicates Tracker accounts for possible changes
in Constant usage after optimization, namely this PR fixes the case when
a Constant register stored in Duplicates Tracker after all passes is
represented by a non-constant expression. In this case we may be sure
that it neither is able to create a duplicate nor is in need of a
special placement as a Constant instruction.
This PR doesn't introduce a new feature, and in this case we rely on
existing set of test cases in the SPIRV Backend test suite to ensure
that this PR doesn't break existing assumptions without introducing new
test cases. There is a reproducer of the issue available as part of SYCL
CTS test suite, however it's a binary of several MB's size. Given the
subtlety of the issue, reduction of the reproducer to a reasonable site
for inclusion into the SPIRV Backend test suite doesn't seem realistic.
This PR reworks implementation of OpSpecConstantOp with ptr-cast
operation (PtrCastToGeneric, GenericCastToPtr). Previous implementation
didn't take into account a lot of use cases, including multiple
inclusion of pointers, reference to a pointer from OpName, etc. A
reproducer is attached as a new test case.
This PR also fixes wrong type inference for IR patterns which generate
new virtual registers without SPIRV type. Previous implementation
assumed always that result has the same address space as a source that
is not the fact, and, for example, led to impossibility to emit a
ptr-cast operation in the reproducer, because wrong type inference
rendered source and destination with the same address space, eliminating
translation of G_ADDRSPACE_CAST.
Two main goals of this PR are:
* to support "Arithmetic with Overflow" intrinsics, including the
special case when those intrinsics are being generated by the
CodeGenPrepare pass during translations with optimization;
* to redirect intrinsics with aggregate return type to be lowered via
GlobalISel operations instead of SPIRV-specific unfolding/lowering (see
https://github.com/llvm/llvm-project/pull/95012).
There is a new test case
`llvm/test/CodeGen/SPIRV/passes/translate-aggregate-uaddo.ll` that
describes and checks the general logics of the translation.
This PR continues a series of PRs aimed to identify and fix flaws in
code emission, to improve pass rates for the mode with expensive checks
set on (see https://github.com/llvm/llvm-project/pull/101732,
https://github.com/llvm/llvm-project/pull/104104,
https://github.com/llvm/llvm-project/pull/106966), having in mind the
ultimate goal of proceeding towards the non-experimental status of
SPIR-V Backend.
The reproducers are:
1) consider `llc -O3 -mtriple=spirv64-unknown-unknown ...` with:
```
define spir_func i32 @foo(i32 %a, ptr addrspace(4) %p) {
entry:
br label %l1
l1:
%e = phi i32 [ %a, %entry ], [ %i, %body ]
%i = add nsw i32 %e, 1
%fl = icmp eq i32 %i, 0
br i1 %fl, label %exit, label %body
body:
store i8 42, ptr addrspace(4) %p
br label %l1
exit:
ret i32 %i
}
```
2) consider `llc -O0 -mtriple=spirv64-unknown-unknown ...` with:
```
define spir_func i32 @foo(i32 %a, ptr addrspace(4) %p) {
entry:
br label %l1
l1: ; preds = %body, %entry
%e = phi i32 [ %a, %entry ], [ %math, %body ]
%0 = call { i32, i1 } @llvm.uadd.with.overflow.i32(i32 %e, i32 1)
%math = extractvalue { i32, i1 } %0, 0
%ov = extractvalue { i32, i1 } %0, 1
br i1 %ov, label %exit, label %body
body: ; preds = %l1
store i8 42, ptr addrspace(4) %p, align 1
br label %l1
exit: ; preds = %l1
ret i32 %math
}
```
Those instructions were inserted either after the instruction using it,
or in the middle of the module.
The first directly causes an issue. The second causes a more subtle
issue: the first type the type is inserted, the emission is fine, but
the second times, the first instruction is reused, without checking its
position in the function. This can lead to the second usage dominating
the definition.
In SPIR-V, types are usually in the header, above all code definition,
but at this stage I don't think we can, so what I do instead is to emit
it in the first basic block.
This commit reduces the failed tests with expensive checks from 107 to
71.
Signed-off-by: Nathan Gauër <brioche@google.com>
This PR continues https://github.com/llvm/llvm-project/pull/101732
changes in virtual register processing aimed to improve correctness of
emitted MIR between passes from the perspective of MachineVerifier.
Namely, the following changes are introduced:
* register classes (lib/Target/SPIRV/SPIRVRegisterInfo.td) and
instruction patterns (lib/Target/SPIRV/SPIRVInstrInfo.td) are corrected
and simplified (by removing unnecessary sophisticated options) -- e.g.,
this PR gets rid of duplicating 32/64 bits patterns, removes ANYID
register class and simplifies definition of the rest of register
classes,
* hardcoded LLT scalar types in passes before instruction selection are
corrected -- the goal is to have correct bit width before instruction
selection, and use 64 bits registers for pattern matching in the
instruction selection pass; 32-bit registers remain where they are
described in such terms by SPIR-V specification (like, for example,
creation of virtual registers for scope/mem semantics operands),
* rework virtual register type/class assignment for calls/builtins
lowering,
* a series of minor changes to fix validity of emitted code between
passes:
- ensure that that bitcast changes the type,
- fix the pattern for instruction selection for OpExtInst,
- simplify inline asm operands usage,
- account for arbitrary integer sizes / update legalizer rules;
* add '-verify-machineinstrs' to existed test cases.
See also https://github.com/llvm/llvm-project/issues/88129 that this PR
may resolve.
This PR fixes a great number of issues reported by MachineVerifier and,
as a result, reduces a number of failed test cases for the mode with
expensive checks set on from ~200 to ~57.
This PR contains changes in virtual register processing aimed to improve
correctness of emitted MIR between passes from the perspective of
MachineVerifier. This potentially helps to detect previously missed
flaws in code emission and harden the test suite. As a measure of
correctness and usefulness of this PR we may use a mode with expensive
checks set on, and MachineVerifier reports problems in the test suite.
In order to satisfy Machine Verifier requirements to MIR correctness not
only a rework of usage of virtual registers' types and classes is
required, but also corrections into pre-legalizer and instruction
selection logics. Namely, the following changes are introduced:
* scalar virtual registers have proper bit width,
* detect register class by SPIR-V type,
* add a superclass for id virtual register classes,
* fix Tablegen rules used for instruction selection,
* fixes of minor existed issues (missed flag for proper representation
of a null constant for OpenCL vs. HLSL, wrong usage of integer virtual
registers as a synonym of any non-type virtual register).
This PR improves type inference of operand presented by opaque pointers
and aggregate types:
* tries to restore original function return type for aggregate types so
that it's possible to deduce a correct type during emit-intrinsics step
(see llvm/test/CodeGen/SPIRV/SpecConstants/restore-spec-type.ll for the
reproducer of the previously existed issue when spirv-val found a
mismatch between object and ptr types in OpStore due to the incorrect
aggregate types tracing),
* explores untyped pointer operands of store to deduce correct pointee
types,
* creates an extension type to track pointee types from emit-intrinsics
step and further instead of direct and naive usage of TypePointerType
that led previously to crashes due to ban of creation of Value of
TypePointerType type,
* tracks instructions with uncomplete type information and tries to
improve their type info after pass calculated types for all machine
functions (it doesn't traverse a code but rather checks only those
instructions which were tracked as uncompleted),
* address more cases of removing unnecessary bitcasts (see, for example,
changes in test/CodeGen/SPIRV/transcoding/OpGenericCastToPtr.ll where
`CHECK-SPIRV-NEXT` in LIT checks show absence of unneeded bitcasts and
unmangled/mangled versions have proper typing now with equivalent type
info),
* address more cases of well known types or relations between types
within instructions (see, for example, atomic*.ll test cases and
Event-related test cases for improved SPIR-V code generated by the
Backend),
* fix the issue of removing unneeded ptrcast instructions in
pre-legalizer pass that led to creation of new assign-type instructions
with the same argument as source in ptrcast and caused errors in type
inference (the reproducer `complex.ll` test case is added to the PR).
This PR fixes https://github.com/llvm/llvm-project/issues/96513.
The way of creation of array type constant was incorrect: instead of
creating [1, 1, 1] or [1, 1, 1, 1, 1, ....] constants, the same [1]
constant was always created, substituting original composite constants.
This in its turn led to a situation when only one of constants might
exist in the code without emitting invalid code, the second constant
would be eventually rewritten to the first constant, because a key to
address both was an array of a single element (like [1]).
This PR fixes the issue and purges from the code unneeded copy/pasted
clone of the function that creates an array constant.
This PR is to add validation to the test case with
get_image_array_size/get_image_dim calls
(transcoding/check_ro_qualifier.ll). This test case didn't pass
validation because of invalid emission of OpCompositeExtract instruction
(Result Type must be the same type as Composite.).
In order to fix the problem this PR improves type inference in general
and partially addresses issues:
* https://github.com/llvm/llvm-project/issues/91998
* https://github.com/llvm/llvm-project/issues/91997
A reproducer from the description of the latter issue is added as a new
test case as a part of this PR.
Only with SPV_INTEL_arbitrary_precision_integers SPIR-V Backend creates
arbitrary sized integer types (<= 64 bits). Without such extension and
according to the SPIR-V specification
`SPIRVGlobalRegistry::getOpTypeInt()` rounds integer sizes other than
8,16,32,64 up, to one of defined by the specification sizes. For the
`DuplicateTracker` class this means that several original LLVM types
(e.g., i2, i4) map to the same "OpTypeInt 8" instruction. This breaks
`DuplicateTracker`'s logic and leads to generation of invalid SPIR-V
code eventually.
For example,
```
define spir_func void @foo(i2 %a, i4 %b) {
entry:
%res2 = tail call i2 @llvm.bitreverse.i2(i2 %a)
%res4 = tail call i4 @llvm.bitreverse.i4(i4 %b)
ret void
}
declare i2 @llvm.bitreverse.i2(i2)
declare i4 @llvm.bitreverse.i4(i4)
```
after translation to SPIR-V would fail during validation (`spirv-val`)
due to two `OpTypeInt 8 0` instructions.
This PR fixes the issue by changing source LLVM type according to the
SPIR-V type that will be used in the emitted code.
This PR contains a series of fixes which are to improve type inference
and instruction selection.
Namely, it includes:
* fix OpSelect to support operands of a pointer type, according to the
SPIR-V specification (previously only integer/float/vectors of integer
or float were supported) -- a new test case is added and existing test
case is updated;
* fix TableGen typo's in definition of register classes and introduce a
new reg class that is a vector of pointers;
* fix usage of a machine function context when there is a need to switch
between different machine functions to infer/validate correct types;
* add usage of TypedPointerType instead of PointerType so that later
stages of type inference are able to distinguish pointer types by their
element types, effectively supporting hierarchy of pointer/pointee types
and avoiding more complicated recursive type matching on level of
machine instructions in favor of direct pointer comparison using LLVM's
`Type *` values;
* extracting detailed information about operand types using known type
rules for some llvm instructions (for instance, by deducing PHI's
operand pointee types if PHI's results type was deducted on previous
stages of type inference), and adding correspondent
`Intrinsic::spv_assign_ptr_type` to keep type info along consequent
passes,
* ensure that OpConstantComposite reuses a constant when it's already
created and available in the same machine function -- otherwise there is
a crash while building a dependency graph, the corresponding test case
is attached,
* implement deduction of function's return type for opaque pointers, a
new test case is attached,
* make 'emit intrinsics' a module pass to resolve function return types
over the module -- first types for all functions of the module must be
calculated, and only after that it's feasible to deduct function return
types on this earlier stage of translation.
The main point of this change was to add support for HLSL's all
intrinsic.
In the process of doing that I found a few issues around creating an
`OpConstantComposite` via `buildZerosVal`.
First the current code didn't support floats so the process of adding
`buildZerosValF` meant I needed a
float version of `getOrCreateIntConstVector`. After doing so I renamed
both versions to `getOrCreateConstVector`. That meant I needed to create
a float type version of `getOrCreateIntCompositeOrNull`. Luckily the
type information was low for this function so was able to split it out
into a helpwe and rename `getOrCreateIntCompositeOrNull` to
`getOrCreateCompositeOrNull` With the exception of type handling
differences of the code and Null vs 0 Constant Op codes these functions
should be identical.
To handle scalar floats I could not use `buildConstantFP` like this PR
did:
https://github.com/llvm/llvm-project/commit/0a2aaab5aba46#diff-733a189c5a8c3211f3a04fd6e719952a3fa231eadd8a7f11e6ecf1e584d57411R1603
because that would create too many superfluous registers (that causes
problems in the validator), I had to create a float version of
`getOrCreateConstInt` which I called `getOrCreateConstFP`.
similar problems with doing it like this:
https://github.com/llvm/llvm-project/blob/main/llvm/lib/Target/SPIRV/SPIRVBuiltins.cpp#L1540.
`buildZerosValF` also has a use of a function `getZeroFP`. This is
because half, float, and double scalar values of 0 would collide in
`SPIRVDuplicatesTracker<Constant> CT` if you use `APFloat(0.0f)`.
`getORCreateConstFP` needed its own version of `getOrCreateConstIntReg`
which I called `getOrCreateConstFloatReg` The one difference in this
function is `getOrCreateConstFloatReg` returns a bit width so we don't
have to call `getScalarOrVectorBitWidth` twice ie when it is used again
in `getOrCreateConstFP` for `OpConstantF` `addNumImm`.
`getOrCreateConstFloatReg` needed an `assignFloatTypeToVReg` helper
which called a `getOrCreateSPIRVFloatType` helper. There was no
equivalent IntegerType::get for floats so I handled this with a switch
statement on bit widths to get the right LLVM float type.
Finally, there is the use of `bool ZeroAsNull = STI.isOpenCLEnv();` This
is partly a cosmetic change. When Zeros are treated as nulls, we don't
create `OpConstantComposite` vectors which is something we do in the
DXCs SPIRV backend. The DXC SPIRV backend also does not use
`OpConstantNull`. Finally, I needed a means to test the behavior of the
OpConstantNull and `OpConstantComposite` changes and this was one way I
could do that via the same tests.
This PR fixes issue https://github.com/llvm/llvm-project/issues/87763
and preserves valid CFG in cases when previous scheme failed to generate
valid code for a switch statement. The PR hardens one existing test case
and adds one more test case as a validation of a new switch generation.
Tests are passing spirv-val now.
This PR also improves validation of forward calls.
This PR:
* fixes OpVariable instructions place in a function (see
https://github.com/llvm/llvm-project/issues/66261),
* improves type inference,
* helps avoiding unneeded bitcasts when validating function call's
This allows to improve existing and add new test cases with more strict
checks. OpVariable fix refers to "All OpVariable instructions in a
function must be the first instructions in the first block" requirement
from SPIR-V spec.
This PR improves type inference in general and deduces types of
composite data structures in particular. Also added a way to insert a
bitcast to make a fun call valid in case of arguments types mismatch due
to opaque pointers type inference.
The attached test `pointers/nested-struct-opaque-pointers.ll`
demonstrates new capabilities: the SPIRV code emitted for this test is
now (1) valid in a sense of data field types and (2) accepted by
`spirv-val`.
More strict LIT checks, support of more composite data structures and
improvement of fun calls from the perspective of type correctness are
main todo's at the moment.
This PR fixes illegal use of OpConstantComposite with non-constant
constituents. The test attached to the PR is able now to satisfy
`spirv-val` check. Before the fix SPIR-V Backend produced for the
attached test case a pattern like
```
%a = OpVariable %_ptr_CrossWorkgroup_uint CrossWorkgroup %uint_123
%11 = OpConstantComposite %_struct_6 %a %a
```
so that `spirv-val` complained with
```
error: line 25: OpConstantComposite Constituent <id> '10[%a]' is not a constant or undef.
%11 = OpConstantComposite %_struct_6 %a %a
```
This PR:
* adds Lifetime intrinsics/instructions
* fixes how the binary header is emitted (correct version and better
approximation of Bound)
* add validation into more test cases
This PR:
* adds support for G_SPLAT_VECTOR generic opcode that may be legally
generated instead of G_BUILD_VECTOR by previous passes of the translator
(see https://github.com/llvm/llvm-project/pull/80378 for the source of
breaking changes);
* improves deduction of types for opaque pointers.
This PR also fixes the following issues:
* if a function has ptr argument(s), two functions that have different
SPIR-V type definitions may get identical LLVM function types and break
agreements of global register and duplicate checker;
* checks for pointer types do not account for TypedPointerType.
Update of tests:
* A test case is added to cover the issue with function ptr parameters.
* The first case, that is support for G_SPLAT_VECTOR generic opcode, is
covered by existing test cases.
* Multiple additional checks by `spirv-val` is added to cover more
possibilities of generation of invalid code.
This PR introduces a step after instruction selection where instructions
can be traversed from the perspective of their validity from the
specification point of view. The PR adds also a way to correct
load/store when there is a type mismatch contradicting the specification
-- an additional bitcast is inserted to keep types consistent.
Correspondent test cases are added and existing test cases are
corrected.
This PR helps to successfully validate with the `spirv-val` tool
(https://github.com/KhronosGroup/SPIRV-Tools) some output that
previously led to validation errors and crashes of back translation from
SPIRV to LLVM IR from the side of SPIRV Translator project
(https://github.com/KhronosGroup/SPIRV-LLVM-Translator).
The added step of bringing instructions to required by the specification
type correspondence can be (should be and will be) extended beyond
load/store instructions to ensure validity rules of other SPIRV
instructions related to type inference.
This PR is to fix a way how SPIR-V Backend describes legality of
OpBitcast instruction and how it is validated on a step of instruction
selection. Instead of checking a size of virtual registers (that makes
no sense due to lack of guarantee of direct relations between size of
virtual register and bit width associated with the type size), this PR
allows to legalize OpBitcast without size check and postpones validation
to the instruction selection step.
As an example, let's consider the next example that was copied as is
from a bigger test suite:
```
%355:id(s16) = G_BITCAST %301:id(s32)
%303:id(s16) = ASSIGN_TYPE %355:id(s16), %349:type(s32)
%644:fid(s32) = G_FMUL %645:fid, %646:fid
%301:id(s32) = ASSIGN_TYPE %644:fid(s32), %40:type(s32)
```
Without the PR this leads to a crash with complains to an illegal
bitcast, because %355 is s16 and %301 is s32. However, we must check not
virtual registers in this case, but types of %355 and %301, i.e.,
%349:type(s32) and %40:type(s32), which are perfectly well compatible in
a sense of OpBitcast in this case.
In a test case that is a part of this PR OpBitcast is legal, being
applied for `OpTypeInt 16` and `OpTypeFloat 16`, but would not be
legalized without this PR due to virtual registers defined as having
size 16 and 32.
The goal of this PR is to tolerate differences between description of
formal arguments by function metadata (represented by "kernel_arg_type")
and LLVM actual parameter types. A compiler may use "kernel_arg_type" of
function metadata fields to encode detailed type information, whereas
LLVM IR may utilize for an actual parameter a more general type, in
particular, opaque pointer type. This PR proposes to resolve this by a
fallback to LLVM actual parameter types during the lowering of formal
function arguments in cases when the type can't be created by string
content of "kernel_arg_type", i.e., when "kernel_arg_type" contains a
type unknown for the SPIR-V Backend.
An example of the issue manifestation is
https://github.com/KhronosGroup/SPIRV-LLVM-Translator/blob/main/test/transcoding/KernelArgTypeInOpString.ll,
where a compiler generates for the following kernel function detailed
`kernel_arg_type` info in a form of `!{!"image_kernel_data*", !"myInt",
!"struct struct_name*"}`, and in LLVM IR same arguments are referred to
as `@foo(ptr addrspace(1) %in, i32 %out, ptr addrspace(1) %outData)`.
Both definitions are correct, and the resulting LLVM IR is correct, but
lowering stage of SPIR-V Backend fails to generate SPIR-V type.
```
typedef int myInt;
typedef struct {
int width;
int height;
} image_kernel_data;
struct struct_name {
int i;
int y;
};
void kernel foo(__global image_kernel_data* in,
__global struct struct_name *outData,
myInt out) {}
```
```
define spir_kernel void @foo(ptr addrspace(1) %in, i32 %out, ptr addrspace(1) %outData) ... !kernel_arg_type !7 ... {
entry:
ret void
}
...
!7 = !{!"image_kernel_data*", !"myInt", !"struct struct_name*"}
```
The PR changes a contract of `SPIRVType *getArgSPIRVType(...)` in a way
that it may return `nullptr` to signal that the metadata string content
is not recognized, so corresponding comments are added and a couple of
checks for `nullptr` are inserted where appropriate.
The patch adds support of the enqueue_kernel builtin function.
It is implemented in the same way as in the SPIRV translator.
2 LIT tests are added to show the improvement.
Differential Revision: https://reviews.llvm.org/D137018
The patch adds the support of OpenCL and SPIR-V built-in types. It also
implements ExtInst selection and adds spv_unreachable and spv_alloca
intrinsics which improve the generation of the corresponding SPIR-V code.
Five LIT tests are included to demonstrate the improvement.
Differential Revision: https://reviews.llvm.org/D132648
Co-authored-by: Aleksandr Bezzubikov <zuban32s@gmail.com>
Co-authored-by: Michal Paszkowski <michal.paszkowski@outlook.com>
Co-authored-by: Andrey Tretyakov <andrey1.tretyakov@intel.com>
Co-authored-by: Konrad Trifunovic <konrad.trifunovic@intel.com>
