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 is a small improvement of parsing of base type name in builtins,
allowing to understand `unsigned ...` types. The test case that fails
without the fix is attached.
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.
SPIR-V intsruction selection was mapping the LLVM float min/max
intrinsics to FMin and FMax respectively for GL/Vulkan environments,
which does not match the intrinsics' documented treatment of NaN
operands. This patch switches the mapping to the correctly matched NMin
and NMax operations.
Fixes#87072
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.
Add support to generate valid SPIR-V for the WaveGetLaneIndex() HLSL
builtin.
To implement this, I had to fix a few small issues in the backend, like
the i8* pointer type being emitted, even if we have the type information
elsewhere.
Signed-off-by: Nathan Gauër <brioche@google.com>
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 improves type inference in SPIR-V Backend for opaque pointers,
accounting or a case when there is a chain of function calls that allows
to deduce formal parameter types from actual arguments. The attached
test demonstrates the case.
SPIRV-LLVM-Translator project
(https://github.com/KhronosGroup/SPIRV-LLVM-Translator) from Khronos
Group is a tool and a library for bi-directional translation between
SPIR-V and LLVM IR. In its backward translation from SPIR-V to LLVM IR
SPIRV-LLVM-Translator isn't necessarily able to cover the same SPIR-V
patterns/instructions set that SPIRV Backend produces, even if we target
the same SPIR-V version in both SPIRV-LLVM-Translator and SPIRV Backend
projects.
To improve interoperability and ability to apply SPIRV Backend output in
different products this PR introduces a notion of a mode of SPIR-V
output that is compatible with a subset of SPIR-V supported by
SPIRV-LLVM-Translator. This includes a new command line option that
doesn't influence default behavior of SPIRV Backend and one test case
that demonstrates how this command line option may be used to get a
practical benefit of producing that one of two possible and similar
output options that can be understood by SPIRV-LLVM-Translator.
This PR:
* adds __spirv_ builtins for existing instructions;
* fixes parsing of "syncscope" values in atomic instructions;
* fix a special case of binary header emision.
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.
Add SPIR-V backend support for the HLSL SV_DispatchThreadID semantic
attribute, which is lowered to a @llvm.dx.thread.id intrinsic in LLVM
IR. In the SPIR-V backend, this is now correctly translated to a
`GlobalInvocationId` builtin variable.
Fixes#82534
This PR is to add explicit support for SPV_KHR_float_controls
(https://github.com/KhronosGroup/SPIRV-Registry/blob/main/extensions/KHR/SPV_KHR_float_controls.asciidoc).
This extension is included into SPIR-V after version 1.4, but in case of
lower versions it is to be included explicitly and OpExtension must be
present in the module with `OpExtension "SPV_KHR_float_controls"`.
This PR fixes this issue and fixes the test case
test/CodeGen/SPIRV/exec_mode_float_control_khr.ll to account for a
version lower than 1.4.
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.
This PR is to add vector reduction instructions according to
https://llvm.org/docs/GlobalISel/GenericOpcode.html#vector-reduction-operations
and widen in such a way a range of successful supported conversions,
covering new cases of vector reduction instructions which IRTranslator
is unable to resolve.
By legalizing vector reduction instructions we introduce a new
instruction patterns that should be addressed, including patterns that
are delegated to pre-legalize step. To address this problem, a new pass
is added that is to bring newly generated instructions after
legalization to an aspect required by instruction selection.
Expected overheads for existing cases is minimal, because a new pass is
working only with newly introduced instructions, otherwise it's just a
additional code traverse without any actions.
This pull request aims to remove any dependency on OpenCL/SPIR-V type
information in LLVM IR metadata. While, using metadata might simplify
and prettify the resulting SPIR-V output (and restore some of the
information missed in the transformation to opaque pointers), the
overall methodology for resolving kernel parameter types is highly
inefficient.
The high-level strategy is to assign kernel parameter types in this order:
1. Resolving the types using builtin function calls as mangled names
must contain type information or by looking up builtin definition in
SPIRVBuiltins.td. Then:
- Assigning the type temporarily using an intrinsic and later setting
the right SPIR-V type in SPIRVGlobalRegistry after IRTranslation
- Inserting a bitcast
2. Defaulting to LLVM IR types (in case of pointers the generic i8*
type or types from byval/byref attributes)
In case of type incompatibility (e.g. parameter defined initially as
sampler_t and later used as image_t) the error will be found early on
before IRTranslation (in the SPIRVEmitIntrinsics pass).
This PR adds SPIR-V extension SPV_INTEL_variable_length_array that
allows to allocate local arrays whose number of elements is unknown at
compile time:
* add a new SPIR-V internal intrinsic:int_spv_alloca_array
* legalize G_STACKSAVE and G_STACKRESTORE
* implement allocation of arrays (previously getArraySize() of
AllocaInst was not used)
* add tests
This PR is to add support for the 'freeze' instruction:
https://llvm.org/docs/LangRef.html#freeze-instruction
There is no way to implement `freeze` correctly without support on
SPIR-V standard side, but we may at least address a simple (static) case
when undef/poison value presence is obvious. The main benefit of even
incomplete `freeze` support is preventing of translation from crashing
due to lack of support on legalization and instruction selection steps.
This PR is to prevent creation of jump tables from switch. The reason is
that SPIR-V doesn't know how to lower jump tables, and a sequence of
commands that IRTranslator generates for switch via jump tables breaks
SPIR-V Backend code generation with complains to G_BRJT. The next
example is the shortest code to break SPIR-V Backend code generation in
this way:
```
target datalayout = "e-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024-n8:16:32:64"
target triple = "spir64-unknown-unknown"
define spir_func void @foo(i32 noundef %val) {
entry:
switch i32 %val, label %sw.epilog [
i32 0, label %sw.bb
i32 1, label %sw.bb2
i32 2, label %sw.bb3
i32 3, label %sw.bb4
]
sw.bb:
br label %sw.epilog
sw.bb2:
br label %sw.epilog
sw.bb3:
br label %sw.epilog
sw.bb4:
br label %sw.epilog
sw.epilog:
ret void
}
```
To resolve the issue we set a high lower limit for number of blocks in a
jump table via getMinimumJumpTableEntries() and prevent undesirable (or
rather unsupported at the moment) path of code generation.
This pull request fixes an issue with missing vector element count
immediate in OpExtInst calls and adds a case for generating bitcasts
before GEPs for kernel arguments of non-matching pointer type. The new
LITs are based on basic/vload_local and basic/vload_global OpenCL CTS
tests. The tests after this change pass SPIR-V validation.
This PR is to add support for the SPIR-V extension
SPV_KHR_uniform_group_instructions that adds new instructions to SPIR-V
to support additional group operations within uniform control flow.
SPIRV-V Backend generates unnecessary OpExecutionMode records, putting
into the id's which are not the Entry Point operands of an OpEntryPoint
(ref: https://github.com/llvm/llvm-project/issues/81753). This PR is to
fix the issue.
This PR adds support for atomic instruction on floating-point numbers:
* SPV_EXT_shader_atomic_float_add
* SPV_EXT_shader_atomic_float_min_max
* SPV_EXT_shader_atomic_float16_add
and fixes asm printer output for half floating-type.
This PR adds support for the SPV_KHR_linkonce_odr extension and modifies
existing negative test with a positive check for the extension and
proper linkage type in case when the extension is enabled.
SPV_KHR_linkonce_odr adds a "LinkOnceODR" linkage type, allowing proper
translation of, for example, C++ templates classes merging during
linking from different modules and supporting any other cases when a
global variable/function must be merged with equivalent global
variable(s)/function(s) from other modules during the linking process.
By SPIR-V specification: "If an instruction, enumerant, or other feature
specifies multiple enabling capabilities, only one such
capability needs to be declared to use the feature."
However, one capability may be preferred over another. One important
case is Shader capability that may not be supported by a backend, but
always is inserted if "OpDecorate SpecId" is found, because Enabling
Capabilities for the latter is the list of Shader and Kernel, where
Shader is coming first and thus always selected as the first available
option.
In this PR we address the problem by keeping current behaviour of
selecting the first option among enabling capabilities as is, but giving
a user a way to filter capabilities during the selection process via a
newly introduced "--avoid-spirv-capabilities" command line option. This
option is to avoid selection of certain capabilities if there are other
available enabling capabilities.
This PR is changing also existing pruneCapabilities() function. It
doesn't remove capability from module requirement anymore, but only adds
implicitly required capabilities recursively, so its name is changed
accordingly. This change fixes the present bug in collecting required by
a module capabilities. Before the change, introduced by this PR,
pruneCapabilities() function has been removing, for example, Kernel
capability from required by a module, because Kernel is initially
required and the second time it was needed pruneCapabilities() removed
it by mistake.
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.
This PR fixes https://github.com/llvm/llvm-project/issues/79057 and
improves code generation for opaque pointers by replacing the culprit
SPIRVGlobalRegistry::getOpTypePointer() call with a more appropriate
SPIRVGlobalRegistry::getOrCreateSPIRVPointerType() call. The latter
function works together with the `DuplicatesTracker`
(`SPIRVGeneralDuplicatesTracker DT;` from `class SPIRVGlobalRegistry`)
to trace existence of previous definitions of opaque pointers. This
allows to produce just one `OpTypePointer` command for all identical
opaque pointers definitions and to return the very same type record for
subsequent `SPIRVGlobalRegistry::createSPIRVType()` invocations.
This PR alone improves code generation by producing a single needed
definition per all opaque pointers to i8 of the same address space
instead of multiple identical definitions produced before the patch.
From the root cause analysis of
https://github.com/llvm/llvm-project/issues/79057 we see also that this
PR resolves the problem of inconsistency between keeping multiple
instruction for identical opaque pointer types and just a single record
for all such instructions in the `DuplicatesTracker`, and so it also
resolves the issue with crashes on creation of a struct with opaque
pointer fields due to the fact that now such struct fields refer to the
same operand `<id>` having a required record in the data structure used
for dependencies analysis (see
https://github.com/llvm/llvm-project/issues/79057).
The goal of this PR is to fix the issue when use of token type in LLVM
intrinsic causes undefined behavior of SPIR-V Backend code generator
when assertions are disabled:
https://github.com/llvm/llvm-project/issues/78434
Among possible fix options, discussed in the
https://github.com/llvm/llvm-project/issues/78434 issue description, the
option to generate a meaningful error before execution arrives at the
`llvm_unreachable` call looks like a better solution for now, because
SPIR-V doesn't support token type anyway without additional extensions.
The PR is to generate a user-friendly error message and exit without
generating a stack dump when such a usage of token type was detected
that would lead to undefined behavior of SPIR-V Backend code generator.
The goal of this PR is to fix the issue of global unnamed variables
causing SPIR-V Backend code generation to crash:
https://github.com/llvm/llvm-project/issues/78278
The reason for the crash is that GlobalValue's getGlobalIdentifier()
would fail for unnamed global variable when trying to access the first
character of the name (see lib/IR/Globals.cpp:150). This leads to assert
in Debug and undefined behaviour in Release builds.
The proposed fix generates a name of an unnamed global variable as
__unnamed_<unsigned number>, in a style of similar existing LLVM
implementation (see lib/IR/Mangler.cpp:131). A new class member variable
is added into `SPIRVInstructionSelector` class to keep track of the
number we give to anonymous global values to generate the same name
every time when this is needed.
The patch adds a new LIT test with the smallest implementation of
reproducer ll code.
Handle a special case when StoreInst's value operand is a kernel
argument of a pointer type. Since these arguments could have either a
basic element type (e.g. float*) or OpenCL builtin type (sampler_t),
bitcast the StoreInst's value operand to default pointer element type
(i8).
This pull request addresses the issue
https://github.com/llvm/llvm-project/issues/72864
Prior to this change spv_ptrcast (and OpBitcast) was never emitted for
GEP resulting pointers. While such SPIR-V was (mostly) accepted by the
NEO GPU driver, the generated SPIR-V was incorrect.
The newly added test (pointers/getelementptr-bitcast-load.ll) verifies
that a correct bitcast is added for more complex cases and passes
spirv-val. The test is based on an OpenCL CTS test (basic/prefetch).
The structurizer will require the frontend to emit convergence
intrinsics. Once uses to restructurize the control-flow, those
intrinsics shall be removed, as they cannot be converted to
SPIR-V.
This commit adds a new pass to the SPIR-V backend which strips those
intrinsics.
Those 2 new steps are not limited to Vulkan as OpenCL could
also benefit from not crashing if a convertent operation is in
the IR (even though the frontend doesn't generate such intrinsics).
Signed-off-by: Nathan Gauër <brioche@google.com>
Add Float16 to Vulkan's available capabilities, and guard Float16Buffer
(Kernel-only capability) against being added outside OpenCL
environments.
Add tests to verify half and half vector types, and validate with
spirv-val.
Fixes#66398
This is the first of the 7 steps outlined in #75801. This PR explicitely
calls the SimplifyLoops pass. Directly following this pass should follow
the 6 others required to structurize the IR.
Running this pass could generate empty basic-blocks, which are implicit
fallthrough to the successor BB.
There was a specific condition in the SPIR-V ISel which handled implicit
fallthrough, but it couldn't work on empty basic-blocks. This commits
removes the old logic, and adds this new logic, which checks all
basic-blocks for implicit fallthroughs, including empty ones.
---------
Signed-off-by: Nathan Gauër <brioche@google.com>
This patch introduces a new spv_ptrcast intrinsic for tracking expected
pointer types. The change fixes multiple OpenCL CTS regressions due the
switch to opaque pointers (e.g. basic/hiloeo).