Use 'neg' operation in SubToAdd

fkie-cad · Sep 20, 2023 · b62a423 · b62a423
1 parent 97ed807
commit b62a423
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Showing 2 changed files with 6 additions and 6 deletions.
diff --git a/decompiler/pipeline/controlflowanalysis/expression_simplification/rules/sub_to_add.py b/decompiler/pipeline/controlflowanalysis/expression_simplification/rules/sub_to_add.py
@@ -1,12 +1,12 @@
 from decompiler.pipeline.controlflowanalysis.expression_simplification.rules.rule import SimplificationRule
-from decompiler.structures.pseudo import BinaryOperation, Constant, Expression, Operation, OperationType
+from decompiler.structures.pseudo import BinaryOperation, Expression, Operation, OperationType, UnaryOperation
 
 
 class SubToAdd(SimplificationRule):
     """
     Replace subtractions with additions.
 
-    `e0 - e1 -> e0 + (e1 * -1)`
+    `e0 - e1 -> e0 + (-e1)`
     """
 
     def apply(self, operation: Operation) -> list[tuple[Expression, Expression]]:
@@ -15,13 +15,13 @@ def apply(self, operation: Operation) -> list[tuple[Expression, Expression]]:
         if not isinstance(operation, BinaryOperation):
             raise TypeError(f"Expected BinaryOperation, got {type(operation)}")
 
-        mul_op = BinaryOperation(OperationType.multiply, [operation.right, Constant(-1, operation.type)])
+        neg_op = UnaryOperation(OperationType.negate, [operation.right])
 
         return [(
             operation,
             BinaryOperation(
                 OperationType.plus,
-                [operation.left, mul_op],
+                [operation.left, neg_op],
                 operation.type
             )
         )]
diff --git a/tests/pipeline/controlflowanalysis/expression_simplification/rules/test_sub_to_add.py b/tests/pipeline/controlflowanalysis/expression_simplification/rules/test_sub_to_add.py
@@ -1,6 +1,6 @@
 import pytest
 from decompiler.pipeline.controlflowanalysis.expression_simplification.rules.sub_to_add import SubToAdd
-from decompiler.structures.pseudo import BinaryOperation, Constant, Expression, Integer, Operation, OperationType, Variable
+from decompiler.structures.pseudo import BinaryOperation, Constant, Expression, Integer, Operation, OperationType, UnaryOperation, Variable
 
 var_x = Variable("x", Integer.int32_t())
 var_y = Variable("y", Integer.int32_t())
@@ -12,7 +12,7 @@
     [
         (
             BinaryOperation(OperationType.minus, [var_x, var_y]),
-            [BinaryOperation(OperationType.plus, [var_x, BinaryOperation(OperationType.multiply, [var_y, con_neg1])])],
+            [BinaryOperation(OperationType.plus, [var_x, UnaryOperation(OperationType.negate, [var_y])])],
         ),
     ],
 )