Implement codegen for when blocks (#501)#501
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daniellerozenblit wants to merge 6 commits intofacebook:devfrom
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Implement codegen for when blocks (#501)#501daniellerozenblit wants to merge 6 commits intofacebook:devfrom
daniellerozenblit wants to merge 6 commits intofacebook:devfrom
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Summary: Pull Request resolved: facebook#501 ## Stack The goal of this stack is to add support for conditional `when` blocks to sddl. ## Diff Implement code generation for `when` blocks, enabling conditional field consumption based on runtime expressions. This diff completes the `when` block feature by adding the code generation phase. Previous diffs in the stack added parsing, semantic analysis, optimizer support, and the `jump_if` VM opcode—this ties them all together. ### Changes - **generateWhen():** New method that generates code for `when` blocks using the `jump_if` opcode. Emits the body instruction count, evaluates the condition, negates it, and conditionally skips the body. - **generateBlock():** Extracted block generation logic from `generate()` to enable reuse for `when` block bodies and record fields. Differential Revision: D96342427
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Summary: Pull Request resolved: facebook#501 ## Stack The goal of this stack is to add support for conditional `when` blocks to sddl. ## Diff Implement code generation for `when` blocks, enabling conditional field consumption based on runtime expressions. This diff completes the `when` block feature by adding the code generation phase. Previous diffs in the stack added parsing, semantic analysis, optimizer support, and the `jump_if` VM opcode—this ties them all together. ### Changes - **generateWhen():** New method that generates code for `when` blocks using the `jump_if` opcode. Emits the body instruction count, evaluates the condition, negates it, and conditionally skips the body. - **generateBlock():** Extracted block generation logic from `generate()` to enable reuse for `when` block bodies and record fields. Differential Revision: D96342427
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Summary: Pull Request resolved: facebook#501 ## Stack The goal of this stack is to add support for conditional `when` blocks to sddl. ## Diff Implement code generation for `when` blocks, enabling conditional field consumption based on runtime expressions. This diff completes the `when` block feature by adding the code generation phase. Previous diffs in the stack added parsing, semantic analysis, optimizer support, and the `jump_if` VM opcode—this ties them all together. ### Changes - **generateWhen():** New method that generates code for `when` blocks using the `jump_if` opcode. Emits the body instruction count, evaluates the condition, negates it, and conditionally skips the body. - **generateBlock():** Extracted block generation logic from `generate()` to enable reuse for `when` block bodies and record fields. Differential Revision: D96342427
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Summary:
## Stack
The goal of this stack is to add support for conditional `when` blocks to sddl.
## Diff
This diff adds parsing and semantic analysis support for `when` blocks in sddl..
### Changes
- **ASTWhen node:** New AST node type representing a conditional `when` block. Contains a condition expression and a body of statements.
- **WhenRule grammar:** New grammar rule that parses `when <expr> { <statements> }` syntax.
- **SemanticAnalyzer:** Added `analyze(ASTWhen)` to validate the condition is numeric and recursively analyze the body statements.
Differential Revision: D96342217
Summary:
## Stack
The goal of this stack is to add support for conditional `when` blocks to sddl.
## Diff
This diff implements optimizer passes for `when` blocks in sddl., enabling constant folding and dead variable elimination for conditional constructs.
### Changes
- **ConstFoldPass:** Implemented `optimizeWhen()` that folds constant conditions—eliminates `when 0 { ... }` blocks entirely (dead code removal) and inlines the body for `when <non-zero> { ... }`.
- **DeadVarPass:** Implemented `optimizeWhen()` that tracks variable references in condition and body, applies dead variable elimination to when body.
Differential Revision: D96342234
Summary: ## Stack The goal of this stack is to add support for conditional `when` blocks to sddl. ## Diff This diff adds a new VM opcode `jump_if` that conditionally skips N instructions based on a condition. This opcode is required for implementing `when` blocks. Differential Revision: D96342363
Summary: Pull Request resolved: facebook#503 ## Stack The goal of this stack is to add support for conditional `when` blocks to sddl. ## Diff Introduce a dedicated `ASTRecordField` type to explicitly represent record fields instead of using `ASSUME` operations. Previously, record fields were represented as `ASSUME` ops (e.g., `field_name assume Type`), which made it difficult to distinguish field declarations from other operations. This change creates a proper AST node type for record fields, improving code clarity and enabling better support for conditional fields in subsequent diffs. Differential Revision: D96342377
Summary: Pull Request resolved: facebook#505 ## Stack The goal of this stack is to add support for conditional `when` blocks to sddl. ## Diff Add semantic analysis check to prevent member access (e.g., `data.optional`) on fields declared inside `when` blocks. Conditional fields may or may not exist at runtime depending on the `when` condition, so allowing direct member access would lead to undefined behavior. Differential Revision: D96347373
Summary: Pull Request resolved: facebook#501 ## Stack The goal of this stack is to add support for conditional `when` blocks to sddl. ## Diff Implement code generation for `when` blocks, enabling conditional field consumption based on runtime expressions. This diff completes the `when` block feature by adding the code generation phase. Previous diffs in the stack added parsing, semantic analysis, optimizer support, and the `jump_if` VM opcode—this ties them all together. ### Changes - **generateWhen():** New method that generates code for `when` blocks using the `jump_if` opcode. Emits the body instruction count, evaluates the condition, negates it, and conditionally skips the body. - **generateBlock():** Extracted block generation logic from `generate()` to enable reuse for `when` block bodies and record fields. Differential Revision: D96342427
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Summary: Pull Request resolved: facebook#501 ## Stack The goal of this stack is to add support for conditional `when` blocks to sddl. ## Diff Implement code generation for `when` blocks, enabling conditional field consumption based on runtime expressions. This diff completes the `when` block feature by adding the code generation phase. Previous diffs in the stack added parsing, semantic analysis, optimizer support, and the `jump_if` VM opcode—this ties them all together. ### Changes - **generateWhen():** New method that generates code for `when` blocks using the `jump_if` opcode. Emits the body instruction count, evaluates the condition, negates it, and conditionally skips the body. - **generateBlock():** Extracted block generation logic from `generate()` to enable reuse for `when` block bodies and record fields. Differential Revision: D96342427
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Summary:
Stack
The goal of this stack is to add support for conditional
whenblocks to sddl.Diff
Implement code generation for
whenblocks, enabling conditional field consumption based on runtime expressions.This diff completes the
whenblock feature by adding the code generation phase. Previous diffs in the stack added parsing, semantic analysis, optimizer support, and thejump_ifVM opcode—this ties them all together.Changes
generateWhen(): New method that generates code for
whenblocks using thejump_ifopcode. Emits the body instruction count, evaluates the condition, negates it, and conditionally skips the body.generateBlock(): Extracted block generation logic from
generate()to enable reuse forwhenblock bodies and record fields.Differential Revision: D96342427