stride3d/stride · error · InvalidOperationException

Cannot determine type for emitted instruction

Error message

Cannot determine type for emitted instruction {instructionId}

What it means

ConstantExpression.GetEmittedTypeId throws InvalidOperationException when the SPIR-V buffer has no instruction matching the given instructionId, so the emitted type cannot be determined. It's used by operandTypeId/resultTypeId to resolve result-type IDs of emitted instructions.

Solutions

Ensure the instruction was emitted into the same SpirvBuffer/SpirvContext being queried (insert temporary buffers via InsertWithoutDuplicates first).
Verify the instructionId corresponds to a valid result ID in the buffer (log the ID range).
If this arises from library code, step through emission order — the instruction may need emitting before its type is queried.

Example fix

// before
var typeId = ConstantExpression.GetEmittedTypeId(context, newId); // newId from temp buffer
// after
context.GetBuffer().InsertWithoutDuplicates(tempBuffer); // make instruction visible first
var typeId = ConstantExpression.GetEmittedTypeId(context, newId);

Defensive patterns

Strategy: try-catch

Validate before calling

if (!context.GetBuffer().TryGetInstructionById(instructionId, out _))
    throw new InvalidOperationException($"Instruction {instructionId} not emitted into this context");

Try / catch

try { typeId = GetEmittedTypeId(context, id); }
catch (InvalidOperationException ex) when (ex.Message.StartsWith("Cannot determine type")) { /* insert buffer or fix emission order */ }

Prevention

Insert temporary emission buffers into the target context before resolving IDs
Never cache instruction IDs across different SpirvContexts
Emit an instruction before querying its result type

When it happens

Trigger: Querying the type of an instruction ID that was never emitted into the current SpirvContext buffer — e.g. an instruction emitted into a standalone buffer while the context queried is a different one, or a stale/incorrect ID passed in.

Common situations: SPIR-V codegen where a constant/expression was emitted into a temporary buffer (Emit-to-temp path) but its ID is resolved against the wrong buffer; internal codegen bugs after refactoring instruction emission.

Understand the failure class

Background: "This is a bug, please report it": internal invariant violations, unreachable panics, and SNH errors explained — this error's family across 47 libraries.

Related errors

AI-assisted analysis of stride3d/stride@96fad776d2 (2026-09-14). Data as JSON: /api/errors/4d158f7858dcef62. Report an issue: GitHub.

Appendix: source

Thrown at sources/shaders/Stride.Shaders.Parsers/Core/ConstantExpression.cs:42

    public abstract bool TryEvaluate(out object? value);

    /// <summary>
    /// Replace GenericParamExpr nodes matching the given declaringClass with resolved values.
    /// Returns this if no substitution occurred.
    /// </summary>
    public virtual ConstantExpression Substitute(string declaringClass, ConstantExpression[] args) => this;

    /// <summary>
    /// Look up the ResultType of an emitted instruction by its ID.
    /// </summary>
    protected static int GetEmittedTypeId(SpirvContext context, int instructionId)
    {
        if (context.GetBuffer().TryGetInstructionById(instructionId, out var inst))
        {
            if (inst.Data.IdResultType is int typeId)
                return typeId;
        }
        throw new InvalidOperationException($"Cannot determine type for emitted instruction {instructionId}");
    }

    /// <summary>
    /// Emit the expression into a temporary standalone SpirvBuffer.
    /// Used when the expression needs to be imported into another context via InsertWithoutDuplicates.
    /// </summary>
    public SpirvBuffer EmitToBuffer()
    {
        var tempContext = new SpirvContext();
        var resultId = Emit(tempContext);
        return SpirvContext.ExtractConstantFromBuffer(resultId, tempContext.GetBuffer());
    }

    /// <summary>
    /// Create a ConstantExpression from a concrete runtime value.
    /// </summary>
    public static ConstantExpression FromValue(object value) => value switch
    {

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