snarkvm_synthesizer_program/function/
bytes.rs

1// Copyright (c) 2019-2025 Provable Inc.
2// This file is part of the snarkVM library.
3
4// Licensed under the Apache License, Version 2.0 (the "License");
5// you may not use this file except in compliance with the License.
6// You may obtain a copy of the License at:
7
8// http://www.apache.org/licenses/LICENSE-2.0
9
10// Unless required by applicable law or agreed to in writing, software
11// distributed under the License is distributed on an "AS IS" BASIS,
12// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13// See the License for the specific language governing permissions and
14// limitations under the License.
15
16use super::*;
17
18impl<N: Network> FromBytes for FunctionCore<N> {
19    /// Reads the function from a buffer.
20    #[inline]
21    fn read_le<R: Read>(mut reader: R) -> IoResult<Self> {
22        // Read the function name.
23        let name = Identifier::<N>::read_le(&mut reader)?;
24
25        // Read the inputs.
26        let num_inputs = u16::read_le(&mut reader)?;
27        if num_inputs > u16::try_from(N::MAX_INPUTS).map_err(error)? {
28            return Err(error(format!("Failed to deserialize a function: too many inputs ({num_inputs})")));
29        }
30        let mut inputs = Vec::with_capacity(num_inputs as usize);
31        for _ in 0..num_inputs {
32            inputs.push(Input::read_le(&mut reader)?);
33        }
34
35        // Read the instructions.
36        let num_instructions = u32::read_le(&mut reader)?;
37        if num_instructions > u32::try_from(N::MAX_INSTRUCTIONS).map_err(error)? {
38            return Err(error(format!("Failed to deserialize a function: too many instructions ({num_instructions})")));
39        }
40        let mut instructions = Vec::with_capacity(num_instructions as usize);
41        for _ in 0..num_instructions {
42            instructions.push(Instruction::read_le(&mut reader)?);
43        }
44
45        // Read the outputs.
46        let num_outputs = u16::read_le(&mut reader)?;
47        if num_outputs > u16::try_from(N::MAX_OUTPUTS).map_err(error)? {
48            return Err(error(format!("Failed to deserialize a function: too many outputs ({num_outputs})")));
49        }
50        let mut outputs = Vec::with_capacity(num_outputs as usize);
51        for _ in 0..num_outputs {
52            outputs.push(Output::read_le(&mut reader)?);
53        }
54
55        // Determine if there is a finalize scope.
56        let variant = u8::read_le(&mut reader)?;
57        let finalize = match variant {
58            0 => None,
59            1 => Some(FinalizeCore::read_le(&mut reader)?),
60            _ => return Err(error(format!("Failed to deserialize a function: invalid finalize variant ({variant})"))),
61        };
62
63        // Initialize a new function.
64        let mut function = Self::new(name);
65        inputs.into_iter().try_for_each(|input| function.add_input(input)).map_err(error)?;
66        instructions.into_iter().try_for_each(|instruction| function.add_instruction(instruction)).map_err(error)?;
67        outputs.into_iter().try_for_each(|output| function.add_output(output)).map_err(error)?;
68        finalize.map(|finalize| function.add_finalize(finalize));
69
70        Ok(function)
71    }
72}
73
74impl<N: Network> ToBytes for FunctionCore<N> {
75    /// Writes the function to a buffer.
76    #[inline]
77    fn write_le<W: Write>(&self, mut writer: W) -> IoResult<()> {
78        // Write the function name.
79        self.name.write_le(&mut writer)?;
80
81        // Write the number of inputs for the function.
82        let num_inputs = self.inputs.len();
83        match num_inputs <= N::MAX_INPUTS {
84            true => u16::try_from(num_inputs).map_err(error)?.write_le(&mut writer)?,
85            false => return Err(error(format!("Failed to write {num_inputs} inputs as bytes"))),
86        }
87
88        // Write the inputs.
89        for input in self.inputs.iter() {
90            input.write_le(&mut writer)?;
91        }
92
93        // Write the number of instructions for the function.
94        let num_instructions = self.instructions.len();
95        match num_instructions <= N::MAX_INSTRUCTIONS {
96            true => u32::try_from(num_instructions).map_err(error)?.write_le(&mut writer)?,
97            false => return Err(error(format!("Failed to write {num_instructions} instructions as bytes"))),
98        }
99
100        // Write the instructions.
101        for instruction in self.instructions.iter() {
102            instruction.write_le(&mut writer)?;
103        }
104
105        // Write the number of outputs for the function.
106        let num_outputs = self.outputs.len();
107        match num_outputs <= N::MAX_OUTPUTS {
108            true => u16::try_from(num_outputs).map_err(error)?.write_le(&mut writer)?,
109            false => return Err(error(format!("Failed to write {num_outputs} outputs as bytes"))),
110        }
111
112        // Write the outputs.
113        for output in self.outputs.iter() {
114            output.write_le(&mut writer)?;
115        }
116
117        // If the finalize scope exists, write it.
118        match &self.finalize_logic {
119            None => 0u8.write_le(&mut writer)?,
120            Some(logic) => {
121                1u8.write_le(&mut writer)?;
122                // Write the finalize scope logic.
123                logic.write_le(&mut writer)?;
124            }
125        }
126
127        Ok(())
128    }
129}
130
131#[cfg(test)]
132mod tests {
133    use super::*;
134    use crate::Function;
135    use console::network::MainnetV0;
136
137    type CurrentNetwork = MainnetV0;
138
139    #[test]
140    fn test_function_bytes() -> Result<()> {
141        let function_string = r"
142function main:
143    input r0 as field.public;
144    input r1 as field.private;
145    add r0 r1 into r2;
146    add r0 r1 into r3;
147    add r0 r1 into r4;
148    add r0 r1 into r5;
149    add r0 r1 into r6;
150    add r0 r1 into r7;
151    add r0 r1 into r8;
152    add r0 r1 into r9;
153    add r0 r1 into r10;
154    add r0 r1 into r11;
155    output r11 as field.private;";
156
157        let expected = Function::<CurrentNetwork>::from_str(function_string)?;
158        let expected_bytes = expected.to_bytes_le()?;
159        println!("String size: {:?}, Bytecode size: {:?}", function_string.len(), expected_bytes.len());
160
161        let candidate = Function::<CurrentNetwork>::from_bytes_le(&expected_bytes)?;
162        assert_eq!(expected.to_string(), candidate.to_string());
163        assert_eq!(expected_bytes, candidate.to_bytes_le()?);
164        Ok(())
165    }
166}
snarkvm_synthesizer_program/function/bytes.rs

snarkvm_synthesizer_program/function/
bytes.rs
