[move-decompiler] Improvements to the astifier

This PR implements some major improvements to the astifier:

- Finally (I think) cracked the way how to do correct topological sorting and managing nested blocks. More complicated examples now produce more reasonable results.
- Rewrote AST transformations for if-then-else and loops.
- Fixed issues with the fixpoint analysis on the AST
- Did some minor fixes in the sourcifier

The generated source is still not correct in some cases, but much better then before.

Cargo.toml

@@ -795,6 +795,7 @@ toml_edit = "0.14.3"
 tracing = "0.1.37"
 tracing-subscriber = { version = "0.3.17", features = ["json", "env-filter"] }
 trybuild = "1.0.80"
+try_match = "0.4.2"
 tokio = { version = "1.35.1", features = ["full"] }
 tokio-io-timeout = "1.2.0"
 tokio-metrics = "0.3.1"

ecosystem/indexer-grpc/indexer-test-transactions/src/lib.rs

@@ -14,6 +14,6 @@ mod tests {
         // Check that the transaction is valid JSON
         let transaction = serde_json::from_slice::<Transaction>(json_bytes).unwrap();
 
-        assert_eq!(transaction.version, 65);
+        assert_eq!(transaction.version, 61);
     }
 }

third_party/move/move-compiler-v2/tests/checking/typing/loop_result_type.exp

@@ -81,6 +81,6 @@ module 0x2::M {
     }
     fun t4() {
         let () = loop break;
-        let () = loop if (false) break;
+        let () = while (!false) ();
     }
 }

third_party/move/move-model/bytecode/Cargo.toml

@@ -25,6 +25,7 @@ num = { workspace = true }
 paste = { workspace = true }
 petgraph = { workspace = true }
 topological-sort = { workspace = true }
+try_match = { workspace = true }
 
 [dev-dependencies]
 anyhow = { workspace = true }

third_party/move/move-model/bytecode/ast-generator-tests/tests/abort_example.exp

@@ -0,0 +1,160 @@
+
+=== Processing m::f =====================================================
+--- Source
+public fun f(length: u64): u64 {
+        assert!(length > 0, 1);
+        assert!(length < 100, 2);
+        let counter = 0;
+        while (counter < length) counter += 1;
+        counter
+    }
+
+--- Stackless Bytecode
+public fun m::f($t0|length: u64): u64 {
+     var $t1|$t3: u64
+     var $t2|$t11: u64 [unused]
+     var $t3: u64
+     var $t4: u64
+     var $t5: bool
+     var $t6: u64
+     var $t7: u64
+     var $t8: u64
+     var $t9: bool
+     var $t10: u64
+     var $t11: u64
+     var $t12: u64
+     var $t13: u64
+     var $t14: bool
+     var $t15: u64
+     var $t16: u64
+     var $t17: u64
+     var $t18: u64
+  0: $t3 := copy($t0)
+  1: $t4 := 0
+  2: $t5 := >($t3, $t4)
+  3: if ($t5) goto 4 else goto 6
+  4: label L1
+  5: goto 9
+  6: label L0
+  7: $t6 := 1
+  8: abort($t6)
+  9: label L2
+ 10: $t7 := copy($t0)
+ 11: $t8 := 100
+ 12: $t9 := <($t7, $t8)
+ 13: if ($t9) goto 14 else goto 16
+ 14: label L4
+ 15: goto 19
+ 16: label L3
+ 17: $t10 := 2
+ 18: abort($t10)
+ 19: label L5
+ 20: $t11 := 0
+ 21: $t1 := $t11
+ 22: goto 23
+ 23: label L10
+ 24: $t12 := copy($t1)
+ 25: $t13 := copy($t0)
+ 26: $t14 := <($t12, $t13)
+ 27: if ($t14) goto 28 else goto 34
+ 28: label L7
+ 29: $t15 := move($t1)
+ 30: $t16 := 1
+ 31: $t17 := +($t15, $t16)
+ 32: $t1 := $t17
+ 33: goto 36
+ 34: label L6
+ 35: goto 38
+ 36: label L8
+ 37: goto 23
+ 38: label L9
+ 39: $t18 := move($t1)
+ 40: return $t18
+}
+
+--- Raw Generated AST
+_t3: u64 = length;
+_t4: u64 = 0;
+_t5: bool = Gt(_t3, _t4);
+loop {
+  if (_t5) break;
+  _t6: u64 = 1;
+  Abort(_t6)
+};
+_t7: u64 = length;
+_t8: u64 = 100;
+_t9: bool = Lt(_t7, _t8);
+loop {
+  if (_t9) break;
+  _t10: u64 = 2;
+  Abort(_t10)
+};
+_t11: u64 = 0;
+_t1: u64 = _t11;
+loop {
+  _t12: u64 = _t1;
+  _t13: u64 = length;
+  _t14: bool = Lt(_t12, _t13);
+  if (Not(_t14)) break;
+  _t15: u64 = _t1;
+  _t16: u64 = 1;
+  _t17: u64 = Add(_t15, _t16);
+  _t1: u64 = _t17;
+  continue
+};
+_t18: u64 = _t1;
+return _t18
+
+--- Assign-Transformed Generated AST
+loop {
+  if (Gt(length, 0)) break;
+  Abort(1)
+};
+loop {
+  if (Lt(length, 100)) break;
+  Abort(2)
+};
+_t1: u64 = 0;
+loop {
+  if (Not(Lt(_t1, length))) break;
+  _t1: u64 = Add(_t1, 1);
+  continue
+};
+return _t1
+
+--- If-Transformed Generated AST
+if (Not(Gt(length, 0))) Abort(1);
+if (Not(Lt(length, 100))) Abort(2);
+_t1: u64 = 0;
+loop {
+  if (Not(Lt(_t1, length))) break;
+  _t1: u64 = Add(_t1, 1);
+  continue
+};
+return _t1
+
+--- Var-Bound Generated AST
+{
+  let _t1: u64;
+  if (Not(Gt(length, 0))) Abort(1);
+  if (Not(Lt(length, 100))) Abort(2);
+  _t1: u64 = 0;
+  loop {
+    if (Not(Lt(_t1, length))) break;
+    _t1: u64 = Add(_t1, 1);
+    continue
+  };
+  return _t1
+}
+
+=== Sourcified Output ============================================
+module 0x815::m {
+    public fun f(length: u64): u64 {
+        let _t1;
+        if (!(length > 0)) abort 1;
+        if (!(length < 100)) abort 2;
+        _t1 = 0;
+        while (_t1 < length) _t1 = _t1 + 1;
+        _t1
+    }
+}

third_party/move/move-model/bytecode/ast-generator-tests/tests/abort_example.move

@@ -0,0 +1,9 @@
+module 0x815::m {
+    public fun f(length: u64): u64 {
+        assert!(length > 0, 1);
+        assert!(length < 100, 2);
+        let counter = 0;
+        while (counter < length) counter += 1;
+        counter
+    }
+}