Merge pull request #17602 from hvitved/rust/cfg-prune-bool-literal

Rust: Prune CFG for obviously impossible `true/false` edges

rust/ql/lib/codeql/rust/controlflow/internal/Completion.qll

@@ -67,14 +67,21 @@ abstract class ConditionalCompletion extends NormalCompletion {
   abstract ConditionalCompletion getDual();
 }
 
+/** Holds if node `n` has the Boolean constant value `value`. */
+private predicate isBooleanConstant(AstNode n, Boolean value) {
+  n.(LiteralExpr).getTextValue() = value.toString()
+  or
+  isBooleanConstant(n.(ParenExpr).getExpr(), value)
+}
+
 /**
  * A completion that represents evaluation of an expression
  * with a Boolean value.
  */
 class BooleanCompletion extends ConditionalCompletion, TBooleanCompletion {
   BooleanCompletion() { this = TBooleanCompletion(value) }
 
-  override predicate isValidForSpecific(AstNode e) {
+  private predicate isValidForSpecific0(AstNode e) {
     e = any(IfExpr c).getCondition()
     or
     any(MatchArm arm).getGuard() = e
@@ -84,7 +91,7 @@ class BooleanCompletion extends ConditionalCompletion, TBooleanCompletion {
       e = expr.getLhs()
     )
     or
-    exists(Expr parent | this.isValidForSpecific(parent) |
+    exists(Expr parent | this.isValidForSpecific0(parent) |
       parent =
         any(PrefixExpr expr |
           expr.getOperatorName() = "!" and
@@ -103,6 +110,15 @@ class BooleanCompletion extends ConditionalCompletion, TBooleanCompletion {
     )
   }
 
+  override predicate isValidForSpecific(AstNode e) {
+    this.isValidForSpecific0(e) and
+    (
+      isBooleanConstant(e, value)
+      or
+      not isBooleanConstant(e, _)
+    )
+  }
+
   /** Gets the dual Boolean completion. */
   override BooleanCompletion getDual() { result = TBooleanCompletion(value.booleanNot()) }
 

rust/ql/lib/codeql/rust/elements/internal/LiteralExprImpl.qll

@@ -1,4 +1,3 @@
-// generated by codegen, remove this comment if you wish to edit this file
 /**
  * This module provides a hand-modifiable wrapper around the generated class `LiteralExpr`.
  *
@@ -12,6 +11,7 @@ private import codeql.rust.elements.internal.generated.LiteralExpr
  * be referenced directly.
  */
 module Impl {
+  // the following QLdoc is generated: if you need to edit it, do it in the schema file
   /**
    * A literal expression. For example:
    * ```rust
@@ -25,5 +25,7 @@ module Impl {
    * true;
    * ```
    */
-  class LiteralExpr extends Generated::LiteralExpr { }
+  class LiteralExpr extends Generated::LiteralExpr {
+    override string toString() { result = this.getTextValue() }
+  }
 }

rust/ql/test/extractor-tests/generated/ArrayExpr/ArrayExpr_getExpr.expected

@@ -1,5 +1,5 @@
-| gen_array_expr.rs:5:5:5:13 | ArrayExpr | 0 | gen_array_expr.rs:5:6:5:6 | LiteralExpr |
-| gen_array_expr.rs:5:5:5:13 | ArrayExpr | 1 | gen_array_expr.rs:5:9:5:9 | LiteralExpr |
-| gen_array_expr.rs:5:5:5:13 | ArrayExpr | 2 | gen_array_expr.rs:5:12:5:12 | LiteralExpr |
-| gen_array_expr.rs:6:5:6:11 | ArrayExpr | 0 | gen_array_expr.rs:6:6:6:6 | LiteralExpr |
-| gen_array_expr.rs:6:5:6:11 | ArrayExpr | 1 | gen_array_expr.rs:6:9:6:10 | LiteralExpr |
+| gen_array_expr.rs:5:5:5:13 | ArrayExpr | 0 | gen_array_expr.rs:5:6:5:6 | 1 |
+| gen_array_expr.rs:5:5:5:13 | ArrayExpr | 1 | gen_array_expr.rs:5:9:5:9 | 2 |
+| gen_array_expr.rs:5:5:5:13 | ArrayExpr | 2 | gen_array_expr.rs:5:12:5:12 | 3 |
+| gen_array_expr.rs:6:5:6:11 | ArrayExpr | 0 | gen_array_expr.rs:6:6:6:6 | 1 |
+| gen_array_expr.rs:6:5:6:11 | ArrayExpr | 1 | gen_array_expr.rs:6:9:6:10 | 10 |

rust/ql/test/extractor-tests/generated/BreakExpr/BreakExpr_getExpr.expected

@@ -1 +1 @@
-| gen_break_expr.rs:12:13:12:27 | BreakExpr | gen_break_expr.rs:12:26:12:27 | LiteralExpr |
+| gen_break_expr.rs:12:13:12:27 | BreakExpr | gen_break_expr.rs:12:26:12:27 | 42 |

rust/ql/test/extractor-tests/generated/IndexExpr/IndexExpr_getIndex.expected

@@ -1,2 +1,2 @@
-| gen_index_expr.rs:5:5:5:12 | IndexExpr | gen_index_expr.rs:5:10:5:11 | LiteralExpr |
-| gen_index_expr.rs:6:5:6:12 | IndexExpr | gen_index_expr.rs:6:10:6:11 | LiteralExpr |
+| gen_index_expr.rs:5:5:5:12 | IndexExpr | gen_index_expr.rs:5:10:5:11 | 42 |
+| gen_index_expr.rs:6:5:6:12 | IndexExpr | gen_index_expr.rs:6:10:6:11 | 42 |

rust/ql/test/extractor-tests/generated/LetStmt/LetStmt_getInitializer.expected

@@ -1,4 +1,4 @@
-| gen_let_stmt.rs:5:5:5:15 | LetStmt | gen_let_stmt.rs:5:13:5:14 | LiteralExpr |
-| gen_let_stmt.rs:6:5:6:20 | LetStmt | gen_let_stmt.rs:6:18:6:19 | LiteralExpr |
+| gen_let_stmt.rs:5:5:5:15 | LetStmt | gen_let_stmt.rs:5:13:5:14 | 42 |
+| gen_let_stmt.rs:6:5:6:20 | LetStmt | gen_let_stmt.rs:6:18:6:19 | 42 |
 | gen_let_stmt.rs:9:5:9:24 | LetStmt | gen_let_stmt.rs:9:18:9:23 | TupleExpr |
 | gen_let_stmt.rs:10:5:12:6 | LetStmt | gen_let_stmt.rs:10:19:10:38 | CallExpr |

rust/ql/test/extractor-tests/generated/LiteralExpr/LiteralExpr.expected

@@ -1,8 +1,8 @@
-| gen_literal_expr.rs:5:5:5:6 | LiteralExpr | getNumberOfAttrs: | 0 | hasTextValue: | yes |
-| gen_literal_expr.rs:6:5:6:8 | LiteralExpr | getNumberOfAttrs: | 0 | hasTextValue: | yes |
-| gen_literal_expr.rs:7:5:7:19 | LiteralExpr | getNumberOfAttrs: | 0 | hasTextValue: | yes |
-| gen_literal_expr.rs:8:5:8:20 | LiteralExpr | getNumberOfAttrs: | 0 | hasTextValue: | yes |
-| gen_literal_expr.rs:9:5:9:7 | LiteralExpr | getNumberOfAttrs: | 0 | hasTextValue: | yes |
-| gen_literal_expr.rs:10:5:10:8 | LiteralExpr | getNumberOfAttrs: | 0 | hasTextValue: | yes |
-| gen_literal_expr.rs:11:5:11:20 | LiteralExpr | getNumberOfAttrs: | 0 | hasTextValue: | yes |
-| gen_literal_expr.rs:12:5:12:8 | LiteralExpr | getNumberOfAttrs: | 0 | hasTextValue: | yes |
+| gen_literal_expr.rs:5:5:5:6 | 42 | getNumberOfAttrs: | 0 | hasTextValue: | yes |
+| gen_literal_expr.rs:6:5:6:8 | 42.0 | getNumberOfAttrs: | 0 | hasTextValue: | yes |
+| gen_literal_expr.rs:7:5:7:19 | "Hello, world!" | getNumberOfAttrs: | 0 | hasTextValue: | yes |
+| gen_literal_expr.rs:8:5:8:20 | b"Hello, world!" | getNumberOfAttrs: | 0 | hasTextValue: | yes |
+| gen_literal_expr.rs:9:5:9:7 | 'x' | getNumberOfAttrs: | 0 | hasTextValue: | yes |
+| gen_literal_expr.rs:10:5:10:8 | b'x' | getNumberOfAttrs: | 0 | hasTextValue: | yes |
+| gen_literal_expr.rs:11:5:11:20 | r"Hello, world!" | getNumberOfAttrs: | 0 | hasTextValue: | yes |
+| gen_literal_expr.rs:12:5:12:8 | true | getNumberOfAttrs: | 0 | hasTextValue: | yes |

rust/ql/test/extractor-tests/generated/LiteralExpr/LiteralExpr_getTextValue.expected

@@ -1,8 +1,8 @@
-| gen_literal_expr.rs:5:5:5:6 | LiteralExpr | 42 |
-| gen_literal_expr.rs:6:5:6:8 | LiteralExpr | 42.0 |
-| gen_literal_expr.rs:7:5:7:19 | LiteralExpr | "Hello, world!" |
-| gen_literal_expr.rs:8:5:8:20 | LiteralExpr | b"Hello, world!" |
-| gen_literal_expr.rs:9:5:9:7 | LiteralExpr | 'x' |
-| gen_literal_expr.rs:10:5:10:8 | LiteralExpr | b'x' |
-| gen_literal_expr.rs:11:5:11:20 | LiteralExpr | r"Hello, world!" |
-| gen_literal_expr.rs:12:5:12:8 | LiteralExpr | true |
+| gen_literal_expr.rs:5:5:5:6 | 42 | 42 |
+| gen_literal_expr.rs:6:5:6:8 | 42.0 | 42.0 |
+| gen_literal_expr.rs:7:5:7:19 | "Hello, world!" | "Hello, world!" |
+| gen_literal_expr.rs:8:5:8:20 | b"Hello, world!" | b"Hello, world!" |
+| gen_literal_expr.rs:9:5:9:7 | 'x' | 'x' |
+| gen_literal_expr.rs:10:5:10:8 | b'x' | b'x' |
+| gen_literal_expr.rs:11:5:11:20 | r"Hello, world!" | r"Hello, world!" |
+| gen_literal_expr.rs:12:5:12:8 | true | true |

rust/ql/test/extractor-tests/generated/LiteralPat/LiteralPat_getLiteral.expected

@@ -1 +1 @@
-| gen_literal_pat.rs:6:9:6:10 | LiteralPat | gen_literal_pat.rs:6:9:6:10 | LiteralExpr |
+| gen_literal_pat.rs:6:9:6:10 | LiteralPat | gen_literal_pat.rs:6:9:6:10 | 42 |

rust/ql/test/extractor-tests/generated/MatchArm/MatchArm_getExpr.expected

@@ -1,4 +1,4 @@
 | gen_match_arm.rs:6:9:6:29 | MatchArm | gen_match_arm.rs:6:28:6:28 | PathExpr |
-| gen_match_arm.rs:7:9:7:26 | MatchArm | gen_match_arm.rs:7:25:7:25 | LiteralExpr |
+| gen_match_arm.rs:7:9:7:26 | MatchArm | gen_match_arm.rs:7:25:7:25 | 0 |
 | gen_match_arm.rs:10:9:10:35 | MatchArm | gen_match_arm.rs:10:30:10:34 | ... / ... |
-| gen_match_arm.rs:11:9:11:15 | MatchArm | gen_match_arm.rs:11:14:11:14 | LiteralExpr |
+| gen_match_arm.rs:11:9:11:15 | MatchArm | gen_match_arm.rs:11:14:11:14 | 0 |

rust/ql/test/extractor-tests/generated/PrefixExpr/PrefixExpr_getExpr.expected

@@ -1,3 +1,3 @@
-| gen_prefix_expr.rs:5:13:5:15 | - ... | gen_prefix_expr.rs:5:14:5:15 | LiteralExpr |
-| gen_prefix_expr.rs:6:13:6:17 | ! ... | gen_prefix_expr.rs:6:14:6:17 | LiteralExpr |
+| gen_prefix_expr.rs:5:13:5:15 | - ... | gen_prefix_expr.rs:5:14:5:15 | 42 |
+| gen_prefix_expr.rs:6:13:6:17 | ! ... | gen_prefix_expr.rs:6:14:6:17 | true |
 | gen_prefix_expr.rs:7:13:7:16 | * ... | gen_prefix_expr.rs:7:14:7:16 | PathExpr |

rust/ql/test/extractor-tests/generated/RangeExpr/RangeExpr_getEnd.expected

@@ -1,4 +1,4 @@
-| gen_range_expr.rs:5:13:5:18 | RangeExpr | gen_range_expr.rs:5:17:5:18 | LiteralExpr |
-| gen_range_expr.rs:6:13:6:17 | RangeExpr | gen_range_expr.rs:6:16:6:17 | LiteralExpr |
-| gen_range_expr.rs:8:13:8:16 | RangeExpr | gen_range_expr.rs:8:15:8:16 | LiteralExpr |
-| gen_range_expr.rs:9:13:9:17 | RangeExpr | gen_range_expr.rs:9:16:9:17 | LiteralExpr |
+| gen_range_expr.rs:5:13:5:18 | RangeExpr | gen_range_expr.rs:5:17:5:18 | 10 |
+| gen_range_expr.rs:6:13:6:17 | RangeExpr | gen_range_expr.rs:6:16:6:17 | 10 |
+| gen_range_expr.rs:8:13:8:16 | RangeExpr | gen_range_expr.rs:8:15:8:16 | 10 |
+| gen_range_expr.rs:9:13:9:17 | RangeExpr | gen_range_expr.rs:9:16:9:17 | 10 |

rust/ql/test/extractor-tests/generated/RangeExpr/RangeExpr_getStart.expected

@@ -1,3 +1,3 @@
-| gen_range_expr.rs:5:13:5:18 | RangeExpr | gen_range_expr.rs:5:13:5:13 | LiteralExpr |
-| gen_range_expr.rs:6:13:6:17 | RangeExpr | gen_range_expr.rs:6:13:6:13 | LiteralExpr |
-| gen_range_expr.rs:7:13:7:16 | RangeExpr | gen_range_expr.rs:7:13:7:14 | LiteralExpr |
+| gen_range_expr.rs:5:13:5:18 | RangeExpr | gen_range_expr.rs:5:13:5:13 | 1 |
+| gen_range_expr.rs:6:13:6:17 | RangeExpr | gen_range_expr.rs:6:13:6:13 | 1 |
+| gen_range_expr.rs:7:13:7:16 | RangeExpr | gen_range_expr.rs:7:13:7:14 | 10 |

rust/ql/test/extractor-tests/generated/RecordExprField/RecordExprField_getExpr.expected

@@ -1,2 +1,2 @@
-| gen_record_expr_field.rs:5:11:5:14 | RecordExprField | gen_record_expr_field.rs:5:14:5:14 | LiteralExpr |
-| gen_record_expr_field.rs:5:17:5:20 | RecordExprField | gen_record_expr_field.rs:5:20:5:20 | LiteralExpr |
+| gen_record_expr_field.rs:5:11:5:14 | RecordExprField | gen_record_expr_field.rs:5:14:5:14 | 1 |
+| gen_record_expr_field.rs:5:17:5:20 | RecordExprField | gen_record_expr_field.rs:5:20:5:20 | 2 |

rust/ql/test/extractor-tests/generated/ReturnExpr/ReturnExpr_getExpr.expected

@@ -1 +1 @@
-| gen_return_expr.rs:5:5:5:13 | ReturnExpr | gen_return_expr.rs:5:12:5:13 | LiteralExpr |
+| gen_return_expr.rs:5:5:5:13 | ReturnExpr | gen_return_expr.rs:5:12:5:13 | 42 |

rust/ql/test/extractor-tests/generated/TupleExpr/TupleExpr_getField.expected

@@ -1,4 +1,4 @@
-| gen_tuple_expr.rs:5:5:5:14 | TupleExpr | 0 | gen_tuple_expr.rs:5:6:5:6 | LiteralExpr |
-| gen_tuple_expr.rs:5:5:5:14 | TupleExpr | 1 | gen_tuple_expr.rs:5:9:5:13 | LiteralExpr |
-| gen_tuple_expr.rs:6:5:6:14 | TupleExpr | 0 | gen_tuple_expr.rs:6:6:6:6 | LiteralExpr |
-| gen_tuple_expr.rs:6:5:6:14 | TupleExpr | 1 | gen_tuple_expr.rs:6:9:6:13 | LiteralExpr |
+| gen_tuple_expr.rs:5:5:5:14 | TupleExpr | 0 | gen_tuple_expr.rs:5:6:5:6 | 1 |
+| gen_tuple_expr.rs:5:5:5:14 | TupleExpr | 1 | gen_tuple_expr.rs:5:9:5:13 | "one" |
+| gen_tuple_expr.rs:6:5:6:14 | TupleExpr | 0 | gen_tuple_expr.rs:6:6:6:6 | 2 |
+| gen_tuple_expr.rs:6:5:6:14 | TupleExpr | 1 | gen_tuple_expr.rs:6:9:6:13 | "two" |

rust/ql/test/extractor-tests/generated/YeetExpr/YeetExpr_getExpr.expected

@@ -1 +1 @@
-| gen_yeet_expr.rs:6:8:6:36 | YeetExpr | gen_yeet_expr.rs:6:16:6:36 | LiteralExpr |
+| gen_yeet_expr.rs:6:8:6:36 | YeetExpr | gen_yeet_expr.rs:6:16:6:36 | "index out of bounds" |

rust/ql/test/extractor-tests/generated/YieldExpr/YieldExpr_getExpr.expected

@@ -1 +1 @@
-| gen_yield_expr.rs:7:13:7:19 | YieldExpr | gen_yield_expr.rs:7:19:7:19 | LiteralExpr |
+| gen_yield_expr.rs:7:13:7:19 | YieldExpr | gen_yield_expr.rs:7:19:7:19 | 1 |

rust/ql/test/extractor-tests/utf8/ast.expected

@@ -36,4 +36,4 @@
 | utf8-identifiers.rs:11:5:11:24 | LetStmt |
 | utf8-identifiers.rs:11:9:11:9 | IdentPat |
 | utf8-identifiers.rs:11:9:11:9 | Name |
-| utf8-identifiers.rs:11:14:11:23 | LiteralExpr |
+| utf8-identifiers.rs:11:14:11:23 | 0.00001f64 |