Merge pull request github#12150 from geoffw0/cfg2

Swift: control flow for #available

Author: geoffw0

swift/ql/.generated.list

@@ -371,7 +371,7 @@ ql/lib/codeql/swift/elements/type/WeakStorageTypeConstructor.qll d88b031ef44d6de
 ql/lib/codeql/swift/elements.qll 82b69a48b7afffeb97cafd9fdc57af96b672e21879580a6cfc3bae2a49bc2c40 82b69a48b7afffeb97cafd9fdc57af96b672e21879580a6cfc3bae2a49bc2c40
 ql/lib/codeql/swift/generated/AstNode.qll 02ca56d82801f942ae6265c6079d92ccafdf6b532f6bcebd98a04029ddf696e4 6216fda240e45bd4302fa0cf0f08f5f945418b144659264cdda84622b0420aa2
 ql/lib/codeql/swift/generated/AvailabilityInfo.qll 996a5cfadf7ca049122a1d1a1a9eb680d6a625ce28ede5504b172eabe7640fd2 4fe6e0325ff021a576fcd004730115ffaa60a2d9020420c7d4a1baa498067b60
-ql/lib/codeql/swift/generated/AvailabilitySpec.qll b7b1d14410927b80d11c80a507b6dfec72da01c403ee5db8ed2fe62efb821187 3aa96ba7cc7d8bf26a0c622130dcb79d24fcd346f9a3134afb08862c0fc18a64
+ql/lib/codeql/swift/generated/AvailabilitySpec.qll fb1255f91bb5e41ad4e9c675a2efbc50d0fb366ea2de68ab7eebd177b0795309 144e0c2e7d6c62ecee43325f7f26dcf437881edf0b75cc1bc898c6c4b61fdeaf
 ql/lib/codeql/swift/generated/Callable.qll 042b4f975f1e416c48b5bf26bee257549eec13fb262f11025375560f75a73582 0434788243bc54e48fec49e4cce93509b9a2333f2079dacb6ffc12c972853540
 ql/lib/codeql/swift/generated/Comment.qll f58b49f6e68c21f87c51e2ff84c8a64b09286d733e86f70d67d3a98fe6260bd6 975bbb599a2a7adc35179f6ae06d9cbc56ea8a03b972ef2ee87604834bc6deb1
 ql/lib/codeql/swift/generated/DbFile.qll a49b2a2cb2788cb49c861ebcd458b8daead7b15adb19c3a9f4db3bf39a0051fc a49b2a2cb2788cb49c861ebcd458b8daead7b15adb19c3a9f4db3bf39a0051fc

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

@@ -122,6 +122,8 @@ private predicate inBooleanContext(ControlFlowElement n) {
 private predicate astInBooleanContext(AstNode n) {
   n = any(ConditionElement condElem).getBoolean().getFullyUnresolved()
   or
+  n = any(ConditionElement condElem).getAvailability().getFullyUnresolved()
+  or
   n = any(StmtCondition stmtCond).getFullyUnresolved()
   or
   exists(RepeatWhileStmt repeat | n = repeat.getCondition().getFullyConverted())

swift/ql/lib/codeql/swift/controlflow/internal/ControlFlowGraphImpl.qll

@@ -249,15 +249,23 @@ module Stmts {
       child.asAstNode() = ast.getAnElement().getPattern().getFullyUnresolved()
       or
       child.asAstNode() = ast.getAnElement().getBoolean().getFullyConverted()
+      or
+      child.asAstNode() = ast.getAnElement().getAvailability().getFullyUnresolved()
     }
 
     predicate firstElement(int i, ControlFlowElement first) {
       // If there is an initializer in the first element, evaluate that first
       astFirst(ast.getElement(i).getInitializer().getFullyConverted(), first)
       or
-      // Otherwise, the first element is a boolean condition.
+      // Otherwise, the first element is...
       not exists(ast.getElement(i).getInitializer()) and
-      astFirst(ast.getElement(i).getBoolean().getFullyConverted(), first)
+      (
+        // ... a boolean condition.
+        astFirst(ast.getElement(i).getBoolean().getFullyConverted(), first)
+        or
+        // ... or an availability check.
+        astFirst(ast.getElement(i).getAvailability().getFullyUnresolved(), first)
+      )
     }
 
     predicate succElement(int i, ControlFlowElement pred, ControlFlowElement succ, Completion c) {
@@ -272,6 +280,9 @@ module Stmts {
         or
         // ... or the boolean ...
         astLast(ast.getElement(i).getBoolean().getFullyConverted(), pred, c)
+        or
+        // ... or the availability check ...
+        astLast(ast.getElement(i).getAvailability().getFullyUnresolved(), pred, c)
       ) and
       // We evaluate the next element
       c instanceof NormalCompletion and
@@ -287,11 +298,17 @@ module Stmts {
       astLast(ast.getAnElement().getPattern().getFullyUnresolved(), last, c) and
       not c.(MatchingCompletion).isMatch()
       or
+      // Stop if an availability check failed
+      astLast(ast.getAnElement().getAvailability().getFullyUnresolved(), last, c) and
+      c instanceof FalseCompletion
+      or
       // Stop if we successfully evaluated all the conditionals
       (
         astLast(ast.getLastElement().getBoolean().getFullyConverted(), last, c)
         or
         astLast(ast.getLastElement().getPattern().getFullyUnresolved(), last, c)
+        or
+        astLast(ast.getLastElement().getAvailability().getFullyUnresolved(), last, c)
       ) and
       c instanceof NormalCompletion
     }
@@ -1770,6 +1787,20 @@ module Exprs {
   }
 }
 
+module AvailabilityInfo {
+  private class AvailabilityInfoTree extends AstStandardPostOrderTree {
+    override AvailabilityInfo ast;
+
+    final override ControlFlowElement getChildElement(int i) {
+      result.asAstNode() = ast.getSpec(i).getFullyUnresolved()
+    }
+  }
+
+  private class AvailabilitySpecTree extends AstLeafTree {
+    override AvailabilitySpec ast;
+  }
+}
+
 private Scope parent(Scope n) {
   result = n.getOuterScope() and
   not n instanceof CfgScope::Range_

swift/ql/lib/codeql/swift/elements/stmt/ConditionElement.qll

@@ -6,5 +6,7 @@ class ConditionElement extends Generated::ConditionElement {
     result = this.getBoolean().toString()
     or
     result = this.getPattern().toString() + " = ... "
+    or
+    result = this.getAvailability().toString()
   }
 }

swift/ql/lib/codeql/swift/generated/AvailabilitySpec.qll

@@ -4,5 +4,11 @@ private import codeql.swift.generated.Raw
 import codeql.swift.elements.AstNode
 
 module Generated {
+  /**
+   * An availability spec, that is, part of an `AvailabilityInfo` condition. For example `iOS 12` and `*` in:
+   * ```
+   * if #available(iOS 12, *)
+   * ```
+   */
   class AvailabilitySpec extends Synth::TAvailabilitySpec, AstNode { }
 }

swift/ql/test/library-tests/ast/PrintAst.expected

@@ -3071,6 +3071,107 @@ cfg.swift:
 #  489|     getElement(7): [IntegerLiteralExpr] 11
 #  490|     getElement(8): [IntegerLiteralExpr] 12
 #  493|     getElement(9): [IntegerLiteralExpr] 13
+#  496| [ConcreteFuncDecl] testAvailable()
+#  496|     InterfaceType = () -> Int
+#  496|   getBody(): [BraceStmt] { ... }
+#  497|     getElement(0): [PatternBindingDecl] var ... = ...
+#  497|       getInit(0): [IntegerLiteralExpr] 0
+#  497|       getPattern(0): [NamedPattern] x
+#  497|     getElement(1): [ConcreteVarDecl] x
+#  497|         Type = Int
+#  499|     getElement(2): [IfStmt] if ... then { ... }
+#  499|       getCondition(): [StmtCondition] StmtCondition
+#  499|         getElement(0): [ConditionElement] #available
+#  499|           getAvailability(): [AvailabilityInfo] #available
+#  499|             getSpec(0): [PlatformVersionAvailabilitySpec] macOS 10
+#  499|             getSpec(1): [OtherAvailabilitySpec] *
+#  499|       getThen(): [BraceStmt] { ... }
+#  500|         getElement(0): [BinaryExpr] ... .+=(_:_:) ...
+#  500|           getFunction(): [MethodLookupExpr] .+=(_:_:)
+#  500|             getBase(): [TypeExpr] Int.Type
+#  500|               getTypeRepr(): [TypeRepr] Int
+#  500|             getMethodRef(): [DeclRefExpr] +=(_:_:)
+#  500|           getArgument(0): [Argument] : &...
+#  500|             getExpr(): [InOutExpr] &...
+#  500|               getSubExpr(): [DeclRefExpr] x
+#  500|           getArgument(1): [Argument] : 1
+#  500|             getExpr(): [IntegerLiteralExpr] 1
+#  503|     getElement(3): [IfStmt] if ... then { ... }
+#  503|       getCondition(): [StmtCondition] StmtCondition
+#  503|         getElement(0): [ConditionElement] #available
+#  503|           getAvailability(): [AvailabilityInfo] #available
+#  503|             getSpec(0): [PlatformVersionAvailabilitySpec] macOS 10.13
+#  503|             getSpec(1): [OtherAvailabilitySpec] *
+#  503|       getThen(): [BraceStmt] { ... }
+#  504|         getElement(0): [BinaryExpr] ... .+=(_:_:) ...
+#  504|           getFunction(): [MethodLookupExpr] .+=(_:_:)
+#  504|             getBase(): [TypeExpr] Int.Type
+#  504|               getTypeRepr(): [TypeRepr] Int
+#  504|             getMethodRef(): [DeclRefExpr] +=(_:_:)
+#  504|           getArgument(0): [Argument] : &...
+#  504|             getExpr(): [InOutExpr] &...
+#  504|               getSubExpr(): [DeclRefExpr] x
+#  504|           getArgument(1): [Argument] : 1
+#  504|             getExpr(): [IntegerLiteralExpr] 1
+#  507|     getElement(4): [IfStmt] if ... then { ... }
+#  507|       getCondition(): [StmtCondition] StmtCondition
+#  507|         getElement(0): [ConditionElement] #unavailable
+#  507|           getAvailability(): [AvailabilityInfo] #unavailable
+#  507|             getSpec(0): [PlatformVersionAvailabilitySpec] iOS 10
+#  507|             getSpec(1): [PlatformVersionAvailabilitySpec] watchOS 10
+#  507|             getSpec(2): [PlatformVersionAvailabilitySpec] macOS 10
+#  507|       getThen(): [BraceStmt] { ... }
+#  508|         getElement(0): [BinaryExpr] ... .+=(_:_:) ...
+#  508|           getFunction(): [MethodLookupExpr] .+=(_:_:)
+#  508|             getBase(): [TypeExpr] Int.Type
+#  508|               getTypeRepr(): [TypeRepr] Int
+#  508|             getMethodRef(): [DeclRefExpr] +=(_:_:)
+#  508|           getArgument(0): [Argument] : &...
+#  508|             getExpr(): [InOutExpr] &...
+#  508|               getSubExpr(): [DeclRefExpr] x
+#  508|           getArgument(1): [Argument] : 1
+#  508|             getExpr(): [IntegerLiteralExpr] 1
+#  511|     getElement(5): [GuardStmt] guard ... else { ... }
+#  511|       getCondition(): [StmtCondition] StmtCondition
+#  511|         getElement(0): [ConditionElement] #available
+#  511|           getAvailability(): [AvailabilityInfo] #available
+#  511|             getSpec(0): [PlatformVersionAvailabilitySpec] macOS 12
+#  511|             getSpec(1): [OtherAvailabilitySpec] *
+#  511|       getBody(): [BraceStmt] { ... }
+#  512|         getElement(0): [BinaryExpr] ... .+=(_:_:) ...
+#  512|           getFunction(): [MethodLookupExpr] .+=(_:_:)
+#  512|             getBase(): [TypeExpr] Int.Type
+#  512|               getTypeRepr(): [TypeRepr] Int
+#  512|             getMethodRef(): [DeclRefExpr] +=(_:_:)
+#  512|           getArgument(0): [Argument] : &...
+#  512|             getExpr(): [InOutExpr] &...
+#  512|               getSubExpr(): [DeclRefExpr] x
+#  512|           getArgument(1): [Argument] : 1
+#  512|             getExpr(): [IntegerLiteralExpr] 1
+#  515|     getElement(6): [IfStmt] if ... then { ... }
+#  515|       getCondition(): [StmtCondition] StmtCondition
+#  515|         getElement(0): [ConditionElement] #available
+#  515|           getAvailability(): [AvailabilityInfo] #available
+#  515|             getSpec(0): [PlatformVersionAvailabilitySpec] macOS 12
+#  515|             getSpec(1): [OtherAvailabilitySpec] *
+#  515|         getElement(1): [ConditionElement] #available
+#  515|           getAvailability(): [AvailabilityInfo] #available
+#  515|             getSpec(0): [PlatformVersionAvailabilitySpec] iOS 12
+#  515|             getSpec(1): [OtherAvailabilitySpec] *
+#  515|       getThen(): [BraceStmt] { ... }
+#  516|         getElement(0): [BinaryExpr] ... .+=(_:_:) ...
+#  516|           getFunction(): [MethodLookupExpr] .+=(_:_:)
+#  516|             getBase(): [TypeExpr] Int.Type
+#  516|               getTypeRepr(): [TypeRepr] Int
+#  516|             getMethodRef(): [DeclRefExpr] +=(_:_:)
+#  516|           getArgument(0): [Argument] : &...
+#  516|             getExpr(): [InOutExpr] &...
+#  516|               getSubExpr(): [DeclRefExpr] x
+#  516|           getArgument(1): [Argument] : 1
+#  516|             getExpr(): [IntegerLiteralExpr] 1
+#  519|     getElement(7): [ReturnStmt] return ...
+#  519|       getResult(): [DeclRefExpr] x
+#  519|       getResult().getFullyConverted(): [LoadExpr] (Int) ...
 declarations.swift:
 #    1| [StructDecl] Foo
 #    2|   getMember(0): [PatternBindingDecl] var ... = ...
@@ -5898,7 +5999,7 @@ statements.swift:
 #   87|   getBody(): [BraceStmt] { ... }
 #   87|     getElement(0): [IfStmt] if ... then { ... }
 #   87|       getCondition(): [StmtCondition] StmtCondition
-#   87|         getElement(0): (no string representation)
+#   87|         getElement(0): [ConditionElement] #available
 #   87|           getAvailability(): [AvailabilityInfo] #available
 #   87|             getSpec(0): [PlatformVersionAvailabilitySpec] macOS 155
 #   87|             getSpec(1): [OtherAvailabilitySpec] *
@@ -5918,7 +6019,7 @@ statements.swift:
 #   91|   getBody(): [BraceStmt] { ... }
 #   91|     getElement(0): [IfStmt] if ... then { ... }
 #   91|       getCondition(): [StmtCondition] StmtCondition
-#   91|         getElement(0): (no string representation)
+#   91|         getElement(0): [ConditionElement] #unavailable
 #   91|           getAvailability(): [AvailabilityInfo] #unavailable
 #   91|             getSpec(0): [PlatformVersionAvailabilitySpec] macOS 42
 #   91|       getThen(): [BraceStmt] { ... }

swift/ql/test/library-tests/ast/cfg.swift

@@ -492,3 +492,29 @@ func testIfConfig() {
 
   13
 }
+
+func testAvailable() -> Int {
+  var x = 0;
+
+  if #available(macOS 10, *) {
+    x += 1
+  }
+
+  if #available(macOS 10.13, *) {
+    x += 1
+  }
+
+  if #unavailable(iOS 10, watchOS 10, macOS 10) {
+    x += 1
+  }
+
+  guard #available(macOS 12, *) else {
+    x += 1
+  }
+
+  if #available(macOS 12, *), #available(iOS 12, *) {
+    x += 1
+  }
+
+  return x
+}