Add DebugBuildIdentifier to the live worklist during initialization#6626
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jkwak-work wants to merge 2 commits intoKhronosGroup:mainfrom
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Add DebugBuildIdentifier to the live worklist during initialization#6626jkwak-work wants to merge 2 commits intoKhronosGroup:mainfrom
jkwak-work wants to merge 2 commits intoKhronosGroup:mainfrom
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DebugBuildIdentifier was missing from the set of NonSemantic debug instructions added to the worklist in InitializeModuleScopeLiveInstructions. Instead it was handled in ProcessGlobalValues (after the worklist is exhausted) using live_insts_.Set() on its direct operands. live_insts_.Set() marks an instruction live but does not enqueue it, so transitive operand dependencies are never visited. In shaders where the only use of a type (e.g. OpTypeInt) is through a constant that is itself only referenced by DebugBuildIdentifier's flags argument, the type instruction is not marked live and is incorrectly killed by ADCE. The surviving constant then references a deleted type, producing invalid SPIR-V. Any subsequent pass that rebuilds the DefUseManager (e.g. CCP) will fail with "Definition is not registered." Fix: include NonSemanticShaderDebugInfo100DebugBuildIdentifier in the worklist loop alongside the other always-live debug instructions. The worklist's transitive closure correctly marks all operand dependencies live before global-value cleanup runs. The existing special-case code in ProcessGlobalValues becomes unreachable for this opcode (IsLive returns true, so the early continue fires) and is now dead; it is left in place for safety.
Adds AggressiveDCETest.KeepDebugBuildIdentifier to verify that DebugBuildIdentifier and its transitive operands (OpTypeInt, OpConstant) are preserved and the output remains valid after ADCE runs. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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@SteveUrquhart , can you re-review this PR? |
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Fixes #6619 |
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This PR includes the latest SPIRV-Tools and the matching SPIRV-Headers. This PR also includes a spirv-opt fix that is currently in a review process: KhronosGroup/SPIRV-Tools#6626
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This PR includes the latest SPIRV-Tools and the matching SPIRV-Headers. This PR also includes a spirv-opt fix that is currently in a review process: KhronosGroup/SPIRV-Tools#6626
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This PR includes the latest SPIRV-Tools and the matching SPIRV-Headers. This PR also includes a spirv-opt fix that is currently in a review process: KhronosGroup/SPIRV-Tools#6626
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DebugBuildIdentifier was missing from the set of NonSemantic debug instructions added to the worklist in InitializeModuleScopeLiveInstructions. Instead it was handled in ProcessGlobalValues (after the worklist is exhausted) using live_insts_.Set() on its direct operands.
live_insts_.Set() marks an instruction live but does not enqueue it, so transitive operand dependencies are never visited. In shaders where the only use of a type (e.g. OpTypeInt) is through a constant that is itself only referenced by DebugBuildIdentifier's flags argument, the type instruction is not marked live and is incorrectly killed by ADCE.
The surviving constant then references a deleted type, producing invalid SPIR-V. Any subsequent pass that rebuilds the DefUseManager (e.g. CCP) will fail with "Definition is not registered."
Fix: include NonSemanticShaderDebugInfo100DebugBuildIdentifier in the worklist loop alongside the other always-live debug instructions. The worklist's transitive closure correctly marks all operand dependencies live before global-value cleanup runs. The existing special-case code in ProcessGlobalValues becomes unreachable for this opcode (IsLive returns true, so the early continue fires) and is now dead; it is left in placefor safety.