From b8abbfd02fc4b7c372e68f06c92da80688b5a4a8 Mon Sep 17 00:00:00 2001
From: zxq5 <zxq5@zxq5.dev>
Date: Thu, 5 Feb 2026 01:11:38 +0000
Subject: [PATCH] added a brainf&&k module to the compiler (specialised module
 so no frontend/backend distinction or use of standard model)

---
 compiler/src/specialised/brainf.rs | 135 +++++++++++++++++++++++++++++
 compiler/src/specialised/mod.rs    |  13 +++
 2 files changed, 148 insertions(+)
 create mode 100644 compiler/src/specialised/brainf.rs
 create mode 100644 compiler/src/specialised/mod.rs

diff --git a/compiler/src/specialised/brainf.rs b/compiler/src/specialised/brainf.rs
new file mode 100644
index 0000000..fe7a2a9
--- /dev/null
+++ b/compiler/src/specialised/brainf.rs
@@ -0,0 +1,135 @@
+#[must_use]
+pub fn build(src: &str) -> String {
+    parse(src).join("\n")
+}
+
+#[must_use]
+#[expect(clippy::too_many_lines)]
+pub fn parse(src: &str) -> Vec<String> {
+    let stack = "0x10000";
+    let acc = "acc";
+    let rga = "rga";
+
+    let bpr = "bpr";
+    let spr = "spr";
+    let mut instrs = Vec::<String>::new();
+
+    // Define symbols
+    let print_start = "print";
+
+    let tokens = lex(src);
+
+    let mut idstack = Vec::<u32>::new();
+
+    // set up a stack
+    instrs.push(format!("\tlwi {}, {}", stack, bpr));
+    instrs.push(format!("\tmov {}, {}", bpr, spr));
+    // set up the data pointer
+    instrs.push(format!("{}: \t lwi 0x30000, {}", "main", rga));
+
+    for (id, tok) in tokens.iter().enumerate() {
+        match tok {
+            BfToken::Inc => {
+                instrs.push(format!("\tinc {}", acc));
+            }
+            BfToken::Dec => {
+                instrs.push(format!("\tdec {}", acc));
+            }
+            BfToken::IncPtr => {
+                instrs.push(format!("\tstw {}, {}, 0", acc, rga));
+                instrs.push(format!("\taddi {}, 4, {}", rga, rga));
+                instrs.push(format!("\tlwd {}, {}, 0", rga, acc));
+            }
+            BfToken::DecPtr => {
+                instrs.push(format!("\tstw {}, {}, 0", acc, rga));
+                instrs.push(format!("\tsubi {}, 4, {}", rga, rga));
+                instrs.push(format!("\tlwd {}, {}, 0", rga, acc));
+            }
+            BfToken::Out => {
+                instrs.push(format!("\tpush {}", acc));
+                instrs.push(format!("\tcall {}", print_start));
+                instrs.push(format!("\tpop zero"));
+            }
+            BfToken::In => {
+                instrs.push(format!("\tlwd 0x40000, {}, 0", acc));
+            }
+            BfToken::Forward => {
+                let loop_start = format!("loop_start_{}", id);
+                let loop_end = format!("loop_end_{}", id);
+                idstack.push(id as u32);
+                instrs.push(format!("\tcmp {}, zero", acc));
+                instrs.push(format!("\tjeq {}, zero", loop_end));
+                instrs.push(format!("{}: \tnop", loop_start));
+            }
+            BfToken::Back => {
+                if let Some(start_id) = idstack.pop() {
+                    let loop_start = format!("loop_start_{}", start_id);
+                    let loop_end = format!("loop_end_{}", start_id);
+                    instrs.push(format!("\tcmp {}, zero", acc));
+                    instrs.push(format!("\tjne {}, zero", loop_start));
+                    instrs.push(format!("{}: \tnop", loop_end));
+                } else {
+                    eprintln!("Warning: Unmatched ']' at position {}", id);
+                }
+            }
+        }
+    }
+
+    instrs.push("\thlt".to_string());
+
+    insert_lib(&mut instrs);
+
+    instrs
+}
+
+fn insert_lib(instrs: &mut Vec<String>) {
+    let bpr = "bpr";
+    let spr = "spr";
+    let rg0 = "rg0";
+    let rg1 = "rg1";
+
+    let print_start = "print";
+    let current = "current";
+    instrs.push(format!("\tdw {}, 0x20000", current));
+    instrs.push(format!("{}: \tpush {}", print_start, bpr));
+    instrs.push(format!("\tmov {}, {}", spr, bpr));
+    instrs.push(format!("\tlwd {}, {}, 8", bpr, rg0));
+    instrs.push(format!("\tlwd {}, {}, 0", current, rg1));
+    instrs.push(format!("\tstb {}, {}, 0", rg0, rg1));
+    instrs.push(format!("\taddi {}, 1, {}", rg1, rg1));
+    instrs.push(format!("\tstw {}, {}, 0", rg1, current));
+    instrs.push(format!("\tmov {}, {}", bpr, spr));
+    instrs.push(format!("\tpop {}", bpr));
+    instrs.push("\treturn".to_string());
+}
+
+enum BfToken {
+    Inc,
+    Dec,
+    IncPtr,
+    DecPtr,
+    Out,
+    In,
+    Forward,
+    Back,
+}
+
+fn lex(src: &str) -> Vec<BfToken> {
+    src.chars()
+        .filter_map(|c| match c {
+            '+' => Some(BfToken::Inc),
+            '-' => Some(BfToken::Dec),
+            '>' => Some(BfToken::IncPtr),
+            '<' => Some(BfToken::DecPtr),
+            '.' => Some(BfToken::Out),
+            ',' => Some(BfToken::In),
+            '[' => Some(BfToken::Forward),
+            ']' => Some(BfToken::Back),
+            _ => None,
+        })
+        .collect()
+}
+
+fn _create_symbol(id: u32) -> String {
+    format!("label_{}", id)
+}
diff --git a/compiler/src/specialised/mod.rs b/compiler/src/specialised/mod.rs
new file mode 100644
index 0000000..2ff89ed
--- /dev/null
+++ b/compiler/src/specialised/mod.rs
@@ -0,0 +1,13 @@
+use crate::model::CompilerError;
+
+pub mod brainf;
+
+pub fn build_specialised(ext: &str, data: &str) -> Option<Result<String, CompilerError>> {
+    match ext {
+        "bf" => {
+            let res = brainf::build(data);
+            Some(Ok(res))
+        }
+        _ => None,
+    }
+}