From 5bf7352ce4bb384dcb32f478743708914794773a Mon Sep 17 00:00:00 2001 From: Michael J Klein Date: Mon, 23 Sep 2024 11:24:23 -0400 Subject: [PATCH] chore: remove bubble_up_constrains (#6127) # Description ## Problem\* This SSA pass is unused ## Summary\* ## Additional Context ## Documentation\* Check one: - [x] No documentation needed. - [ ] Documentation included in this PR. - [ ] **[For Experimental Features]** Documentation to be submitted in a separate PR. # PR Checklist\* - [x] I have tested the changes locally. - [x] I have formatted the changes with [Prettier](https://prettier.io/) and/or `cargo fmt` on default settings. --- .../src/ssa/opt/bubble_up_constrains.rs | 152 ------------------ compiler/noirc_evaluator/src/ssa/opt/mod.rs | 1 - 2 files changed, 153 deletions(-) delete mode 100644 compiler/noirc_evaluator/src/ssa/opt/bubble_up_constrains.rs diff --git a/compiler/noirc_evaluator/src/ssa/opt/bubble_up_constrains.rs b/compiler/noirc_evaluator/src/ssa/opt/bubble_up_constrains.rs deleted file mode 100644 index 0409f0e6a49..00000000000 --- a/compiler/noirc_evaluator/src/ssa/opt/bubble_up_constrains.rs +++ /dev/null @@ -1,152 +0,0 @@ -use std::collections::HashMap; - -use crate::ssa::{ - ir::instruction::{Instruction, InstructionId}, - ssa_gen::Ssa, -}; - -impl Ssa { - /// A simple SSA pass to go through each instruction and move every `Instruction::Constrain` to immediately - /// after when all of its inputs are available. - #[tracing::instrument(level = "trace", skip(self))] - pub(crate) fn bubble_up_constrains(mut self) -> Ssa { - for function in self.functions.values_mut() { - for block in function.reachable_blocks() { - let instructions = function.dfg[block].take_instructions(); - let mut filtered_instructions = Vec::with_capacity(instructions.len()); - - // Multiple constrains can bubble up to sit under a single instruction. We want to maintain the ordering of these constraints, - // so we need to keep track of how many constraints are attached to a given instruction. - // Some assertions don't operate on instruction results, so we use Option so we also track the None case - let mut inserted_at_instruction: HashMap, usize> = - HashMap::with_capacity(instructions.len()); - - let dfg = &function.dfg; - for instruction in instructions { - let (lhs, rhs) = match dfg[instruction] { - Instruction::Constrain(lhs, rhs, ..) => (lhs, rhs), - _ => { - filtered_instructions.push(instruction); - continue; - } - }; - - let last_instruction_that_creates_inputs = filtered_instructions - .iter() - .rev() - .position(|&instruction_id| { - let results = dfg.instruction_results(instruction_id).to_vec(); - results.contains(&lhs) || results.contains(&rhs) - }) - // We iterate through the previous instructions in reverse order so the index is from the - // back of the vector - .map(|reversed_index| filtered_instructions.len() - reversed_index - 1); - - let insertion_index = last_instruction_that_creates_inputs - .map(|index| { - // We want to insert just after the last instruction that creates the inputs - index + 1 - }) - // If it doesn't depend from the previous instructions, then we insert at the start - .unwrap_or_default(); - - let already_inserted_for_this_instruction = inserted_at_instruction - .entry( - last_instruction_that_creates_inputs - .map(|index| filtered_instructions[index]), - ) - .or_default(); - - filtered_instructions.insert( - insertion_index + *already_inserted_for_this_instruction, - instruction, - ); - - *already_inserted_for_this_instruction += 1; - } - - *function.dfg[block].instructions_mut() = filtered_instructions; - } - } - self - } -} - -#[cfg(test)] -mod test { - use crate::ssa::{ - function_builder::FunctionBuilder, - ir::{ - instruction::{Binary, BinaryOp, Instruction}, - map::Id, - types::Type, - }, - }; - - #[test] - fn check_bubble_up_constrains() { - // fn main f0 { - // b0(v0: Field): - // v1 = add v0, Field 1 - // v2 = add v1, Field 1 - // constrain v0 == Field 1 'With message' - // constrain v2 == Field 3 - // constrain v0 == Field 1 - // constrain v1 == Field 2 - // constrain v1 == Field 2 'With message' - // } - // - let main_id = Id::test_new(0); - - // Compiling main - let mut builder = FunctionBuilder::new("main".into(), main_id); - let v0 = builder.add_parameter(Type::field()); - - let one = builder.field_constant(1u128); - let two = builder.field_constant(2u128); - let three = builder.field_constant(3u128); - - let v1 = builder.insert_binary(v0, BinaryOp::Add, one); - let v2 = builder.insert_binary(v1, BinaryOp::Add, one); - builder.insert_constrain(v0, one, Some("With message".to_string().into())); - builder.insert_constrain(v2, three, None); - builder.insert_constrain(v0, one, None); - builder.insert_constrain(v1, two, None); - builder.insert_constrain(v1, two, Some("With message".to_string().into())); - builder.terminate_with_return(vec![]); - - let ssa = builder.finish(); - - // Expected output: - // - // fn main f0 { - // b0(v0: Field): - // constrain v0 == Field 1 'With message' - // constrain v0 == Field 1 - // v1 = add v0, Field 1 - // constrain v1 == Field 2 - // constrain v1 == Field 2 'With message' - // v2 = add v1, Field 1 - // constrain v2 == Field 3 - // } - // - let ssa = ssa.bubble_up_constrains(); - let main = ssa.main(); - let block = &main.dfg[main.entry_block()]; - assert_eq!(block.instructions().len(), 7); - - let expected_instructions = vec![ - Instruction::Constrain(v0, one, Some("With message".to_string().into())), - Instruction::Constrain(v0, one, None), - Instruction::Binary(Binary { lhs: v0, rhs: one, operator: BinaryOp::Add }), - Instruction::Constrain(v1, two, None), - Instruction::Constrain(v1, two, Some("With message".to_string().into())), - Instruction::Binary(Binary { lhs: v1, rhs: one, operator: BinaryOp::Add }), - Instruction::Constrain(v2, three, None), - ]; - - for (index, instruction) in block.instructions().iter().enumerate() { - assert_eq!(&main.dfg[*instruction], &expected_instructions[index]); - } - } -} diff --git a/compiler/noirc_evaluator/src/ssa/opt/mod.rs b/compiler/noirc_evaluator/src/ssa/opt/mod.rs index bd9d0baff97..f3dbd58fa69 100644 --- a/compiler/noirc_evaluator/src/ssa/opt/mod.rs +++ b/compiler/noirc_evaluator/src/ssa/opt/mod.rs @@ -6,7 +6,6 @@ mod array_set; mod as_slice_length; mod assert_constant; -mod bubble_up_constrains; mod constant_folding; mod defunctionalize; mod die;