Added an assertion to constant evaluation enty points that prohibits dependent expressions

Summary:
Constant evaluator does not work on value-dependent or type-dependent
expressions.

Also fixed bugs uncovered by these assertions.

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D61522

llvm-svn: 361050

2 files changed, 16 insertions, 4 deletions

diff --git a/clang/lib/Sema/SemaOpenMP.cpp b/clang/lib/Sema/SemaOpenMP.cpp
index cc196219092..19a7d784c56 100644
--- a/clang/lib/Sema/SemaOpenMP.cpp
+++ b/clang/lib/Sema/SemaOpenMP.cpp
@@ -5894,14 +5894,21 @@ checkOpenMPLoop(OpenMPDirectiveKind DKind, Expr *CollapseLoopCountExpr,
   if (CollapseLoopCountExpr) {
     // Found 'collapse' clause - calculate collapse number.
     Expr::EvalResult Result;
-    if (CollapseLoopCountExpr->EvaluateAsInt(Result, SemaRef.getASTContext()))
+    if (!CollapseLoopCountExpr->isValueDependent() &&
+        CollapseLoopCountExpr->EvaluateAsInt(Result, SemaRef.getASTContext())) {
       NestedLoopCount = Result.Val.getInt().getLimitedValue();
+    } else {
+      Built.clear(/*size=*/1);
+      return 1;
+    }
   }
   unsigned OrderedLoopCount = 1;
   if (OrderedLoopCountExpr) {
     // Found 'ordered' clause - calculate collapse number.
     Expr::EvalResult EVResult;
-    if (OrderedLoopCountExpr->EvaluateAsInt(EVResult, SemaRef.getASTContext())) {
+    if (!OrderedLoopCountExpr->isValueDependent() &&
+        OrderedLoopCountExpr->EvaluateAsInt(EVResult,
+                                            SemaRef.getASTContext())) {
       llvm::APSInt Result = EVResult.Val.getInt();
       if (Result.getLimitedValue() < NestedLoopCount) {
         SemaRef.Diag(OrderedLoopCountExpr->getExprLoc(),
@@ -5912,6 +5919,9 @@ checkOpenMPLoop(OpenMPDirectiveKind DKind, Expr *CollapseLoopCountExpr,
             << CollapseLoopCountExpr->getSourceRange();
       }
       OrderedLoopCount = Result.getLimitedValue();
+    } else {
+      Built.clear(/*size=*/1);
+      return 1;
     }
   }
   // This is helper routine for loop directives (e.g., 'for', 'simd',
diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index 256c2343e51..eadc01e5efb 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -6376,7 +6376,8 @@ EnableIfAttr *Sema::CheckEnableIf(FunctionDecl *Function, ArrayRef<Expr *> Args,
     APValue Result;
     // FIXME: This doesn't consider value-dependent cases, because doing so is
     // very difficult. Ideally, we should handle them more gracefully.
-    if (!EIA->getCond()->EvaluateWithSubstitution(
+    if (EIA->getCond()->isValueDependent() ||
+        !EIA->getCond()->EvaluateWithSubstitution(
             Result, Context, Function, llvm::makeArrayRef(ConvertedArgs)))
       return EIA;
 
@@ -9562,7 +9563,8 @@ static bool isFunctionAlwaysEnabled(const ASTContext &Ctx,
                                     const FunctionDecl *FD) {
   for (auto *EnableIf : FD->specific_attrs<EnableIfAttr>()) {
     bool AlwaysTrue;
-    if (!EnableIf->getCond()->EvaluateAsBooleanCondition(AlwaysTrue, Ctx))
+    if (EnableIf->getCond()->isValueDependent() ||
+        !EnableIf->getCond()->EvaluateAsBooleanCondition(AlwaysTrue, Ctx))
       return false;
     if (!AlwaysTrue)
       return false;