diff options
| -rw-r--r-- | tvix/eval/src/opcode.rs | 39 |
1 files changed, 37 insertions, 2 deletions
diff --git a/tvix/eval/src/opcode.rs b/tvix/eval/src/opcode.rs index 04f9ca25556c..a6c59278d286 100644 --- a/tvix/eval/src/opcode.rs +++ b/tvix/eval/src/opcode.rs @@ -54,30 +54,65 @@ pub struct Count(pub usize); /// All variants of this enum carry a bounded amount of data to /// ensure that no heap allocations are needed for an Opcode. +/// +/// In documentation comments, stack positions are referred to by +/// indices written in `{}` as such, where required: +/// +/// ```notrust +/// --- top of the stack +/// / +/// v +/// [ ... | 3 | 2 | 1 | 0 ] +/// ^ +/// / +/// 2 values deep --- +/// ``` +/// +/// Unless otherwise specified, operations leave their result at the +/// top of the stack. #[warn(variant_size_differences)] #[derive(Clone, Copy, Debug, PartialEq, Eq)] pub enum OpCode { /// Push a constant onto the stack. OpConstant(ConstantIdx), + // Unary operators /// Discard a value from the stack. OpPop, - // Unary operators + /// Invert the boolean at the top of the stack. OpInvert, + + // Binary operators + /// Invert the sign of the number at the top of the stack. OpNegate, - // Arithmetic binary operators + /// Sum up the two numbers at the top of the stack. OpAdd, + + /// Subtract the number at {1} from the number at {2}. OpSub, + + /// Multiply the two numbers at the top of the stack. OpMul, + + /// Divide the two numbers at the top of the stack. OpDiv, // Comparison operators + /// Check the two values at the top of the stack for Nix-equality. OpEqual, + + /// Check whether the value at {2} is less than {1}. OpLess, + + /// Check whether the value at {2} is less than or equal to {1}. OpLessOrEq, + + /// Check whether the value at {2} is greater than {1}. OpMore, + + /// Check whether the value at {2} is greater than or equal to {1}. OpMoreOrEq, // Logical operators & generic jumps |