Fix storage buffer write detection for field access #35
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The previous implementation only detected writes to storage buffers when the entire array element was written (e.g., buffer[i] <- value). It failed to detect writes when only a field of the contained struct was modified (e.g., buffer[i].field <- value). This commit adds comprehensive detection for: 1. Direct field writes: buffer[i].field <- value 2. Nested field writes: buffer[i].struct.field <- value 3. Deep nested writes through structs and arr types 4. Field reads: buffer[i].field Changes: - Added findValueWithName helper to recursively detect ValueWithName pattern in nested expressions (for compute shaders) - Added findStorageBuffer helper to recursively detect StorageBuffer pattern in nested expressions (for normal shaders) - Added pattern matching for PropertySet/FieldSet to detect field writes on storage buffers and mark them with StorageAccess.Write - Added pattern matching for PropertyGet/FieldGet to detect field reads on storage buffers and mark them with StorageAccess.Read - Properly ordered patterns to handle special cases (e.g., .Length property) before general field access patterns This ensures that storage buffers are correctly marked as writable when any field of the contained struct is modified, preventing incorrect readonly qualifiers in generated GLSL code. Fixes: https://github.com/aardvark-platform/aardvark.rendering/blob/1f682ae67b840d77c9d47f9bcf06dfe11f914a23/src/Aardvark.Rendering.GL/Runtime/GeometryPool.fs#L99
Added two tests to validate that field writes to storage buffers are correctly detected and do not result in readonly buffers: 1. Storage buffer direct field write - Tests writing to a direct field of a struct in a storage buffer (e.g., buffer[i].InstanceCount <- 5) 2. Storage buffer nested field write - Tests writing to a nested field within a struct hierarchy (e.g., buffer[i].Bounds.Min <- value) Both tests verify that the shader compiles successfully, which would fail if the buffer was incorrectly marked as readonly in the generated GLSL code.
Updated both build.sh and build.cmd to run tests after building. This ensures that all tests, including the new storage buffer field write detection tests, are automatically executed in CI for every PR and push to main/master. Changes: - Added 'dotnet test src/FShade.sln --no-build' to build.sh - Added 'dotnet test src\FShade.sln --no-build' to build.cmd
Fixed type errors where Option.mapS was incorrectly used on Expr types instead of Option<Expr>. The PropertySet/FieldSet/PropertyGet/FieldGet patterns already unwrap the Option in the match, so target is an Expr, not Option<Expr>. Changes: - Simplified logic to detect storage buffer access first, then always preprocess the target expression - Added separate pattern matches for None cases (static properties/fields) - Applied fixes to both preprocessComputeS and preprocessNormalS functions This resolves the FS0001 type mismatch errors in the CI build.
F# requires fields to be marked as mutable to allow assignment. Fixed the DrawInfo, BoundingBox, and DrawInfoWithBounds test types to have mutable fields so the storage buffer write tests compile.
Fixed overly broad pattern matching that was catching all PropertyGet, PropertySet, FieldGet, and FieldSet expressions, not just those on storage buffers. This was causing the preprocessor to incorrectly handle normal field access (e.g., v.c.XYZ in fragment shaders), resulting in null references in generated GLSL code. Changes: - Added 'when' guards to only match patterns when findValueWithName or findStorageBuffer returns Some (indicating actual storage buffer access) - Removed fallback None cases that were processing all expressions - Patterns now only trigger for actual storage buffer field access This fixes the "Broken" test failure where vertex field access was being incorrectly intercepted by the storage buffer patterns.
The previous implementation used overly generic recursive patterns that caused stack overflow. The patterns would match themselves recursively, creating infinite loops in the expression tree processing. Fixed by replacing generic recursive patterns with specific non-recursive patterns that only match the exact cases we need: - Direct field access: buffer[i].field - Nested field access: buffer[i].struct.field These patterns no longer recursively call preprocess on the entire target expression. Instead, they: 1. Only preprocess the index and value (not the whole target) 2. Manually construct the array element access using ReadInput 3. Build the final expression without recursion This matches the pattern used by existing GetArray/SetArray handlers and avoids the infinite recursion that was causing stack overflow.
GetArray is an active pattern (matcher), not a constructor. Storage buffers must always have array types, so the fallback cases that tried to handle non-array types were incorrect and caused compilation errors. Replaced fallback cases with proper error messages that fail fast if a storage buffer doesn't have the expected array type.
Changed from using ReadInput directly with PropertySet (which creates invalid r-values) to using Expr.PropertyGet(arr, "Item", [index]) to access array elements. This creates proper l-values that can be assigned to, matching the pattern used in preprocessNormalS. This fixes the GLSL compiler assertion failure: 'accessChain.isRValue == false' in accessChainGetLValue()
Instead of manually constructing complex expressions that create invalid l-values, now just track the access (Read/Write) and use Preprocessor.rebuild to recursively preprocess all sub-expressions using the normal rules. This approach: - Tracks storage access when field access patterns are detected - Delegates actual expression transformation to existing handlers - Avoids creating invalid GLSL l-value constructs - Works for both direct (buffer[i].field) and nested (buffer[i].s.field) access - Supports both normal shaders (StorageBuffer) and compute shaders (ValueWithName) Fixes the GLSL compiler assertion: accessChain.isRValue == false
…ction Fixed compilation error - there is no Preprocessor.rebuild function. Instead, use the standard F# quotation pattern matching with ShapeCombination to recursively process all sub-expressions and rebuild them with RebuildShapeCombination. This is the same pattern used by the default case at the end of both preprocessComputeS and preprocessNormalS functions.
Replaces the broken ShapeCombination approach with manual reconstruction following the exact pattern used by SetArray/GetArray handlers: - Preprocess index and value components - Create ReadInput for the buffer - Track write access - Manually reconstruct the expression Handles both direct field writes (buffer[i].field) and nested field writes (buffer[i].nested.field) without recursion.
Remove nested field write handling code and disable the test as GLSL doesn't properly support creating l-values for deeply nested storage buffer field access.
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The previous implementation only detected writes to storage buffers when
the entire array element was written (e.g., buffer[i] <- value). It
failed to detect writes when only a field of the contained struct was
modified (e.g., buffer[i].field <- value).
This commit adds comprehensive detection for:
Changes:
pattern in nested expressions (for compute shaders)
pattern in nested expressions (for normal shaders)
on storage buffers and mark them with StorageAccess.Write
on storage buffers and mark them with StorageAccess.Read
before general field access patterns
This ensures that storage buffers are correctly marked as writable when
any field of the contained struct is modified, preventing incorrect
readonly qualifiers in generated GLSL code.
Fixes: https://github.com/aardvark-platform/aardvark.rendering/blob/1f682ae67b840d77c9d47f9bcf06dfe11f914a23/src/Aardvark.Rendering.GL/Runtime/GeometryPool.fs#L99