[Vulkan] Fix SPIR-V 1.4+ entry-point interfaces

[wilx]

What changed

This updates Vulkan code generation for targets requesting SPIR-V 1.4 or newer:

• propagate max_spirv_version into SPIRVSupport and emit that version in the SPIR-V header;
• track storage-buffer arguments, uniform buffers, push constants, and other module-scope variables;
• include those variables in the OpEntryPoint interface list for SPIR-V 1.4+;
• retain TVM's historical SPIR-V 1.0 output for older targets.

Why this is necessary

SPIR-V 1.4 changed the OpEntryPoint contract: every module-scope variable used by an entry point must be listed in its interface operands. TVM previously listed only built-in variables.

TVM also always emitted a SPIR-V 1.0 header, even when the Vulkan target advertised SPIR-V 1.5. That caused validation to use the older rules and masked the incomplete interface list. Reassembling a generated storage-buffer kernel as SPIR-V 1.5 and validating it for Vulkan 1.2 produced:

Interface variable id <4> is used by entry point 'main_kernel' id <2>,
but is not listed as an interface
%A_ptr = OpVariable ... StorageBuffer

Local validation used the smallest useful kernel, B[0] = A[0] + 1. Its generated instructions were reassembled with spirv-as --target-env spv1.5 and independently validated with spirv-val --target-env vulkan1.2. This external-tool validation is intentionally not part of the Python test suite.

After the fix, its entry point contains both storage buffers:

OpEntryPoint GLCompute ... "main_kernel" %BuiltInLocalInvocationId %A_ptr %B_ptr

Validation

• Built TVM's Vulkan and LLVM-enabled compiler successfully.

• Ran the complete repository lint suite:

  pre-commit run --all-files
  All hooks passed
  

• Ran the complete Vulkan codegen test module:

  30 passed, 24 skipped
  

• Confirmed git diff --check passes.

[gemini-code-assist]

Code Review

This pull request updates the Vulkan SPIR-V code generator to support and emit SPIR-V versions 1.4 and above, rather than hardcoding SPIR-V 1.0. Specifically, it adds support for tracking and emitting module-scope variables in the OpEntryPoint interface list, which is required starting with SPIR-V 1.4. It also introduces a max_spirv_version target attribute and adds a test to validate SPIR-V 1.5 output. The review feedback correctly points out an outdated comment in the new test file that should be updated to reflect the new behavior.

Important

The consumer version of Gemini Code Assist on GitHub is being sunset. Starting June 18, 2026, new organization installations will be blocked, and all code review activity will officially cease on July 17, 2026.
For more details on the timeline and next steps, please review the Help Documentation.

[gemini-code-assist]

The comment states that 'TVM currently emits a SPIR-V 1.0 header even when the target supports SPIR-V 1.5.' However, this PR specifically fixes this behavior so that TVM now correctly emits the requested SPIR-V version (e.g., 1.5) in the header. This comment should be updated to reflect the new correct behavior.

Suggested change

	# TVM currently emits a SPIR-V 1.0 header even when the target supports
	# SPIR-V 1.5. Reassembling the generated instructions for SPIR-V 1.5
	# makes spirv-val enforce the Vulkan 1.2 entry-point interface rules.
	# Reassembling the generated instructions for SPIR-V 1.5
	# makes spirv-val enforce the Vulkan 1.2 entry-point interface rules.

[wilx]

FYI, this is completely ChatGPT/Codex generated. I was just experimenting with it and it found this issue. HTH.

[tqchen]

given this depends on spriv tools, i would skip this test, instead rely on local validaiton that the patch works

[wilx]

Removed.