This PR addresses a TODO in
lib/Target/SPIRV/SPIRVInstructionSelector.cpp by adding implementation
of the non-const G_BUILD_VECTOR, and fix emission of the
OpGroupBroadcast instruction for the case when the `..._group_broadcast`
builtin has more than one `local_id` argument and `OpGroupBroadcast`
requires a newly constructed vector with 2 or 3 components instead of
originally passed series of `local_id` arguments.
This PR may resolve https://github.com/llvm/llvm-project/issues/97310 if
the reason for the reported fail is an incorrectly generated
OpGroupBroadcast instruction that was definitely a case.
Existing test is hardened and a new test is added to cover this special
case of the OpGroupBroadcast instruction emission.
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 adds builtin functions to insert instructions from 'Group and
Subgroup' section of the SPIR-V Specification. Corresponding tests are
updated, `spirv-val` run is added where it was missed.
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.
