Merge pull request #15817 from github/rdmarsh2/suppress-expr-destructors

C++: Suppress implicit destructors on expr in preparation for destructors on temporaries

Author: jketema

cpp/ql/lib/semmle/code/cpp/ir/implementation/raw/internal/TranslatedElement.qll

@@ -96,6 +96,9 @@ private predicate ignoreExprAndDescendants(Expr expr) {
   exists(BuiltInVarArgsStart vaStartExpr |
     vaStartExpr.getLastNamedParameter().getFullyConverted() = expr
   )
+  or
+  // suppress destructors of temporary variables until proper support is added for them.
+  exists(Expr parent | parent.getAnImplicitDestructorCall() = expr)
 }
 
 /**
@@ -744,9 +747,13 @@ newtype TTranslatedElement =
   // The declaration/initialization part of a `ConditionDeclExpr`
   TTranslatedConditionDecl(ConditionDeclExpr expr) { not ignoreExpr(expr) } or
   // The side effects of a `Call`
-  TTranslatedCallSideEffects(CallOrAllocationExpr expr) { not ignoreSideEffects(expr) } or
+  TTranslatedCallSideEffects(CallOrAllocationExpr expr) {
+    not ignoreExpr(expr) and
+    not ignoreSideEffects(expr)
+  } or
   // The non-argument-specific side effect of a `Call`
   TTranslatedCallSideEffect(Expr expr, SideEffectOpcode opcode) {
+    not ignoreExpr(expr) and
     not ignoreSideEffects(expr) and
     opcode = getCallSideEffectOpcode(expr)
   } or
@@ -764,6 +771,7 @@ newtype TTranslatedElement =
   // Constructor calls lack a qualifier (`this`) expression, so we need to handle the side effects
   // on `*this` without an `Expr`.
   TTranslatedStructorQualifierSideEffect(Call call, SideEffectOpcode opcode) {
+    not ignoreExpr(call) and
     not ignoreSideEffects(call) and
     call instanceof ConstructorCall and
     opcode = getASideEffectOpcode(call, -1)

cpp/ql/lib/semmle/code/cpp/ir/implementation/raw/internal/TranslatedExpr.qll

@@ -97,19 +97,6 @@ abstract class TranslatedExpr extends TranslatedElement {
     )
   }
 
-  final override predicate hasAnImplicitDestructorCall() {
-    exists(expr.getAnImplicitDestructorCall())
-  }
-
-  final override int getFirstDestructorCallIndex() {
-    not this.handlesDestructorsExplicitly() and
-    (
-      result = max(int childId | exists(this.getChildInternal(childId))) + 1
-      or
-      not exists(this.getChildInternal(_)) and result = 0
-    )
-  }
-
   final override Locatable getAst() { result = expr }
 
   final override Declaration getFunction() { result = getEnclosingDeclaration(expr) }

cpp/ql/test/library-tests/ir/ir/raw_ir.expected

@@ -12779,7 +12779,7 @@ ir.cpp:
 # 2215|     r2215_1(glval<bool>)    = VariableAddress[b]              : 
 # 2215|     r2215_2(bool)           = Load[b]                         : &:r2215_1, ~m?
 # 2215|     v2215_3(void)           = ConditionalBranch               : r2215_2
-#-----|   False -> Block 5
+#-----|   False -> Block 4
 #-----|   True -> Block 3
 
 # 2212|   Block 1
@@ -12796,44 +12796,35 @@ ir.cpp:
 # 2216|     r2216_3(char *)          = Convert                          : r2216_2
 # 2216|     mu2216_4(char *)         = Store[#throw2216:7]              : &:r2216_1, r2216_3
 # 2216|     v2216_5(void)            = ThrowValue                       : &:r2216_1, ~m?
-#-----|   Exception -> Block 6
+#-----|   Exception -> Block 5
 
-# 2219|   Block 4
-# 2219|     r2219_1(glval<String>)  = VariableAddress[s]              : 
+# 2218|   Block 4
+# 2218|     r2218_1(glval<String>)  = VariableAddress[s2]             : 
+# 2218|     mu2218_2(String)        = Uninitialized[s2]               : &:r2218_1
+# 2218|     r2218_3(glval<unknown>) = FunctionAddress[String]         : 
+# 2218|     v2218_4(void)           = Call[String]                    : func:r2218_3, this:r2218_1
+# 2218|     mu2218_5(unknown)       = ^CallSideEffect                 : ~m?
+# 2218|     mu2218_6(String)        = ^IndirectMayWriteSideEffect[-1] : &:r2218_1
+# 2219|     r2219_1(glval<String>)  = VariableAddress[s2]             : 
 # 2219|     r2219_2(glval<unknown>) = FunctionAddress[~String]        : 
 # 2219|     v2219_3(void)           = Call[~String]                   : func:r2219_2, this:r2219_1
 # 2219|     mu2219_4(unknown)       = ^CallSideEffect                 : ~m?
 # 2219|     v2219_5(void)           = ^IndirectReadSideEffect[-1]     : &:r2219_1, ~m?
 # 2219|     mu2219_6(String)        = ^IndirectMayWriteSideEffect[-1] : &:r2219_1
-#-----|   Goto -> Block 5
-
-# 2218|   Block 5
-# 2218|     r2218_1(glval<String>)   = VariableAddress[s2]             : 
-# 2218|     mu2218_2(String)         = Uninitialized[s2]               : &:r2218_1
-# 2218|     r2218_3(glval<unknown>)  = FunctionAddress[String]         : 
-# 2218|     v2218_4(void)            = Call[String]                    : func:r2218_3, this:r2218_1
-# 2218|     mu2218_5(unknown)        = ^CallSideEffect                 : ~m?
-# 2218|     mu2218_6(String)         = ^IndirectMayWriteSideEffect[-1] : &:r2218_1
-# 2219|     r2219_7(glval<String>)   = VariableAddress[s2]             : 
-# 2219|     r2219_8(glval<unknown>)  = FunctionAddress[~String]        : 
-# 2219|     v2219_9(void)            = Call[~String]                   : func:r2219_8, this:r2219_7
-# 2219|     mu2219_10(unknown)       = ^CallSideEffect                 : ~m?
-# 2219|     v2219_11(void)           = ^IndirectReadSideEffect[-1]     : &:r2219_7, ~m?
-# 2219|     mu2219_12(String)        = ^IndirectMayWriteSideEffect[-1] : &:r2219_7
-# 2219|     r2219_13(glval<String>)  = VariableAddress[s]              : 
-# 2219|     r2219_14(glval<unknown>) = FunctionAddress[~String]        : 
-# 2219|     v2219_15(void)           = Call[~String]                   : func:r2219_14, this:r2219_13
-# 2219|     mu2219_16(unknown)       = ^CallSideEffect                 : ~m?
-# 2219|     v2219_17(void)           = ^IndirectReadSideEffect[-1]     : &:r2219_13, ~m?
-# 2219|     mu2219_18(String)        = ^IndirectMayWriteSideEffect[-1] : &:r2219_13
-#-----|   Goto -> Block 11
+# 2219|     r2219_7(glval<String>)  = VariableAddress[s]              : 
+# 2219|     r2219_8(glval<unknown>) = FunctionAddress[~String]        : 
+# 2219|     v2219_9(void)           = Call[~String]                   : func:r2219_8, this:r2219_7
+# 2219|     mu2219_10(unknown)      = ^CallSideEffect                 : ~m?
+# 2219|     v2219_11(void)          = ^IndirectReadSideEffect[-1]     : &:r2219_7, ~m?
+# 2219|     mu2219_12(String)       = ^IndirectMayWriteSideEffect[-1] : &:r2219_7
+#-----|   Goto -> Block 10
 
-# 2220|   Block 6
+# 2220|   Block 5
 # 2220|     v2220_1(void) = CatchByType[const char *] : 
-#-----|   Exception -> Block 8
-#-----|   Goto -> Block 7
+#-----|   Exception -> Block 7
+#-----|   Goto -> Block 6
 
-# 2220|   Block 7
+# 2220|   Block 6
 # 2220|     r2220_2(glval<char *>)  = VariableAddress[s]              : 
 # 2220|     mu2220_3(char *)        = InitializeParameter[s]          : &:r2220_2
 # 2220|     r2220_4(char *)         = Load[s]                         : &:r2220_2, ~m?
@@ -12850,25 +12841,25 @@ ir.cpp:
 # 2221|     v2221_10(void)          = ThrowValue                      : &:r2221_1, ~m?
 #-----|   Exception -> Block 2
 
-# 2223|   Block 8
+# 2223|   Block 7
 # 2223|     v2223_1(void) = CatchByType[const String &] : 
-#-----|   Exception -> Block 10
-#-----|   Goto -> Block 9
+#-----|   Exception -> Block 9
+#-----|   Goto -> Block 8
 
-# 2223|   Block 9
+# 2223|   Block 8
 # 2223|     r2223_2(glval<String &>) = VariableAddress[e]       : 
 # 2223|     mu2223_3(String &)       = InitializeParameter[e]   : &:r2223_2
 # 2223|     r2223_4(String &)        = Load[e]                  : &:r2223_2, ~m?
 # 2223|     mu2223_5(unknown)        = InitializeIndirection[e] : &:r2223_4
 # 2223|     v2223_6(void)            = NoOp                     : 
-#-----|   Goto -> Block 11
+#-----|   Goto -> Block 10
 
-# 2225|   Block 10
+# 2225|   Block 9
 # 2225|     v2225_1(void) = CatchAny : 
 # 2226|     v2226_1(void) = ReThrow  : 
 #-----|   Exception -> Block 2
 
-# 2228|   Block 11
+# 2228|   Block 10
 # 2228|     v2228_1(void) = NoOp       : 
 # 2212|     v2212_9(void) = ReturnVoid : 
 #-----|   Goto -> Block 1

cpp/ql/test/library-tests/syntax-zoo/aliased_ssa_consistency.expected

@@ -9,7 +9,6 @@ sideEffectWithoutPrimary
 instructionWithoutSuccessor
 | ms_try_mix.cpp:35:13:35:19 | ThrowValue: throw ... | Instruction 'ThrowValue: throw ...' has no successors in function '$@'. | ms_try_mix.cpp:29:6:29:19 | void ms_finally_mix(int) | void ms_finally_mix(int) |
 | ms_try_mix.cpp:53:5:53:11 | ThrowValue: throw ... | Instruction 'ThrowValue: throw ...' has no successors in function '$@'. | ms_try_mix.cpp:49:6:49:28 | void ms_empty_finally_at_end() | void ms_empty_finally_at_end() |
-| statements.cpp:25:5:25:9 | ReThrow: re-throw exception  | Instruction 'ReThrow: re-throw exception ' has no successors in function '$@'. | statements.cpp:21:6:21:16 | void early_throw(int) | void early_throw(int) |
 | stmt_expr.cpp:27:5:27:15 | Store: ... = ... | Instruction 'Store: ... = ...' has no successors in function '$@'. | stmt_expr.cpp:21:13:21:13 | void stmtexpr::g(int) | void stmtexpr::g(int) |
 ambiguousSuccessors
 unexplainedLoop

cpp/ql/test/library-tests/syntax-zoo/raw_consistency.expected

@@ -10,9 +10,6 @@ sideEffectWithoutPrimary
 instructionWithoutSuccessor
 | ms_try_mix.cpp:35:13:35:19 | ThrowValue: throw ... | Instruction 'ThrowValue: throw ...' has no successors in function '$@'. | ms_try_mix.cpp:29:6:29:19 | void ms_finally_mix(int) | void ms_finally_mix(int) |
 | ms_try_mix.cpp:53:5:53:11 | ThrowValue: throw ... | Instruction 'ThrowValue: throw ...' has no successors in function '$@'. | ms_try_mix.cpp:49:6:49:28 | void ms_empty_finally_at_end() | void ms_empty_finally_at_end() |
-| statements.cpp:25:5:25:9 | ReThrow: re-throw exception  | Instruction 'ReThrow: re-throw exception ' has no successors in function '$@'. | statements.cpp:21:6:21:16 | void early_throw(int) | void early_throw(int) |
-| statements.cpp:26:3:26:3 | IndirectMayWriteSideEffect: inner | Instruction 'IndirectMayWriteSideEffect: inner' has no successors in function '$@'. | statements.cpp:21:6:21:16 | void early_throw(int) | void early_throw(int) |
-| statements.cpp:28:1:28:1 | IndirectMayWriteSideEffect: before | Instruction 'IndirectMayWriteSideEffect: before' has no successors in function '$@'. | statements.cpp:21:6:21:16 | void early_throw(int) | void early_throw(int) |
 | stmt_expr.cpp:27:5:27:15 | Store: ... = ... | Instruction 'Store: ... = ...' has no successors in function '$@'. | stmt_expr.cpp:21:13:21:13 | void stmtexpr::g(int) | void stmtexpr::g(int) |
 | stmt_expr.cpp:29:11:32:11 | CopyValue: (statement expression) | Instruction 'CopyValue: (statement expression)' has no successors in function '$@'. | stmt_expr.cpp:21:13:21:13 | void stmtexpr::g(int) | void stmtexpr::g(int) |
 | stmt_in_type.cpp:5:53:5:53 | Constant: 1 | Instruction 'Constant: 1' has no successors in function '$@'. | stmt_in_type.cpp:2:6:2:12 | void cpp_fun() | void cpp_fun() |

cpp/ql/test/library-tests/syntax-zoo/unaliased_ssa_consistency.expected

@@ -9,7 +9,6 @@ sideEffectWithoutPrimary
 instructionWithoutSuccessor
 | ms_try_mix.cpp:35:13:35:19 | ThrowValue: throw ... | Instruction 'ThrowValue: throw ...' has no successors in function '$@'. | ms_try_mix.cpp:29:6:29:19 | void ms_finally_mix(int) | void ms_finally_mix(int) |
 | ms_try_mix.cpp:53:5:53:11 | ThrowValue: throw ... | Instruction 'ThrowValue: throw ...' has no successors in function '$@'. | ms_try_mix.cpp:49:6:49:28 | void ms_empty_finally_at_end() | void ms_empty_finally_at_end() |
-| statements.cpp:25:5:25:9 | ReThrow: re-throw exception  | Instruction 'ReThrow: re-throw exception ' has no successors in function '$@'. | statements.cpp:21:6:21:16 | void early_throw(int) | void early_throw(int) |
 | stmt_expr.cpp:27:5:27:15 | Store: ... = ... | Instruction 'Store: ... = ...' has no successors in function '$@'. | stmt_expr.cpp:21:13:21:13 | void stmtexpr::g(int) | void stmtexpr::g(int) |
 ambiguousSuccessors
 unexplainedLoop