Pointer static analysis

Cargo.toml

@@ -1,6 +1,7 @@
 [workspace]
 members = [
     "c2rust",
+    "c2rust-analyze",
     "c2rust-transpile",
     "c2rust-ast-builder",
     "c2rust-ast-exporter",

c2rust-analyze/.gitignore

@@ -0,0 +1,2 @@
+/inspect/
+*.rlib

c2rust-analyze/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "c2rust-analyze"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+polonius-engine = "0.13.0"
+rustc-hash = "1.1.0"
+bitflags = "1.3.2"
+
+[build-dependencies]
+rustc-private-link = { path = "../rustc-private-link" }
+print_bytes = "0.6"
+
+[package.metadata.rust-analyzer]
+rustc_private = true

c2rust-analyze/README.md

@@ -0,0 +1,7 @@
+```sh
+cargo run --bin c2rust-analyze -- tests/filecheck/insertion_sort.rs -L "$(rustc --print sysroot)/lib/rustlib/x86_64-unknown-linux-gnu/lib" --crate-type rlib
+```
+
+This should produce a large amount of debug output, including a table at the
+end listing the type and expression rewrites the analysis has inferred for the
+`insertion_sort` function.

c2rust-analyze/build.rs

@@ -0,0 +1,9 @@
+use rustc_private_link::SysRoot;
+
+fn main() {
+    let sysroot = SysRoot::resolve();
+    sysroot.link_rustc_private();
+
+    print!("cargo:rustc-env=C2RUST_TARGET_LIB_DIR=");
+    print_bytes::println_bytes(&sysroot.rustlib());
+}

c2rust-analyze/rename_nll_facts.py

@@ -0,0 +1,139 @@
+'''
+Usage: `python3 rename_nll_facts.py src ref dest`
+
+Renames atoms in `src/*.facts` to match the names used in `ref/*.facts`, then
+writes the renamed facts to `dest/`.
+'''
+
+import ast
+from collections import defaultdict
+import os
+import sys
+
+src_dir, ref_dir, dest_dir = sys.argv[1:]
+
+# Map `src` loan/origin/path names to `ref` loan/origin/path names.  We don't
+# break this down by type because the names for each type don't collide anyway.
+name_map = {}
+# Set of `ref` names that appear as values in `name_map`.
+ref_names_seen = set()
+
+def match_name(src_name, ref_name):
+    if src_name in name_map:
+        old_ref_name = name_map[src_name]
+        if ref_name != old_ref_name:
+            print('error: %r matches both %r and %r' % (
+                src_name, old_ref_name, ref_name))
+            return
+    else:
+        if ref_name in ref_names_seen:
+            print('error: %r matches %r, but %r is already used' % (
+                src_name, ref_name, ref_name))
+            return
+        name_map[src_name] = ref_name
+        ref_names_seen.add(ref_name)
+
+def match_loan(src_name, ref_name):
+    match_name(src_name, ref_name)
+
+def match_origin(src_name, ref_name):
+    match_name(src_name, ref_name)
+
+def match_path(src_name, ref_name):
+    match_name(src_name, ref_name)
+
+
+def load(name):
+    with open(os.path.join(src_dir, name + '.facts')) as f:
+        src_rows = [[ast.literal_eval(s) for s in line.strip().split('\t')]
+                for line in f]
+    with open(os.path.join(ref_dir, name + '.facts')) as f:
+        ref_rows = [[ast.literal_eval(s) for s in line.strip().split('\t')]
+                for line in f]
+    return src_rows, ref_rows
+
+
+# Match up paths using `path_is_var` and `path_assigned_at_base`.
+
+def match_path_is_var():
+    src, ref = load('path_is_var')
+    ref_dct = {var: path for path, var in ref}
+    for path, var in src:
+        if var not in ref_dct:
+            continue
+        match_path(path, ref_dct[var])
+
+match_path_is_var()
+
+def match_path_assigned_at_base():
+    src, ref = load('path_assigned_at_base')
+    ref_dct = {point: path for path, point in ref}
+    for path, point in src:
+        if point not in ref_dct:
+            continue
+        match_path(path, ref_dct[point])
+
+match_path_assigned_at_base()
+
+# Match up origins and loans using `loan_issued_at`
+
+def match_loan_issued_at():
+    src, ref = load('loan_issued_at')
+    ref_dct = {point: (origin, loan) for origin, loan, point in ref}
+    for origin, loan, point in src:
+        if point not in ref_dct:
+            continue
+        match_origin(origin, ref_dct[point][0])
+        match_origin(loan, ref_dct[point][1])
+
+match_loan_issued_at()
+
+# Match up origins using `use_of_var_derefs_origin`
+
+def match_use_of_var_derefs_origin():
+    src, ref = load('use_of_var_derefs_origin')
+    src_dct = defaultdict(list)
+    for var, origin in src:
+        src_dct[var].append(origin)
+    ref_dct = defaultdict(list)
+    for var, origin in ref:
+        ref_dct[var].append(origin)
+    for var in set(src_dct.keys()) & set(ref_dct.keys()):
+        src_origins = src_dct[var]
+        ref_origins = ref_dct[var]
+        if len(src_origins) != len(ref_origins):
+            print('error: var %r has %d origins in src but %d in ref' % (
+                var, len(src_origins), len(ref_origins)))
+            continue
+        for src_origin, ref_origin in zip(src_origins, ref_origins):
+            match_origin(src_origin, ref_origin)
+
+match_use_of_var_derefs_origin()
+
+
+# Rewrite `src` using the collected name mappings.
+
+os.makedirs(dest_dir, exist_ok=True)
+for name in os.listdir(src_dir):
+    if name.startswith('.') or not name.endswith('.facts'):
+        continue
+
+    with open(os.path.join(src_dir, name)) as src, \
+            open(os.path.join(dest_dir, name), 'w') as dest:
+        for line in src:
+            src_parts = [ast.literal_eval(s) for s in line.strip().split('\t')]
+            dest_parts = []
+            for part in src_parts:
+                if part.startswith('_') or part.startswith('Start') or part.startswith('Mid'):
+                    dest_parts.append(part)
+                    continue
+
+                dest_part = name_map.get(part)
+                if dest_part is None:
+                    print('error: no mapping for %r (used in %s: %r)' % (
+                        part, name, src_parts))
+                    dest_part = 'OLD:' + part
+                dest_parts.append(dest_part)
+
+            dest.write('\t'.join('"%s"' % part for part in dest_parts) + '\n')
+

c2rust-analyze/rust-toolchain

@@ -0,0 +1 @@
+../rust-toolchain