Vector [Sema]. Vector "splats" which are truncated should have a warning
with -Wconversion. // rdar://16502418
llvm-svn: 205646
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 93c5cac..9cd44d2 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -6113,11 +6113,20 @@
/// implicit conversions in the given expression. There are a couple
/// of competing diagnostics here, -Wconversion and -Wsign-compare.
void AnalyzeImplicitConversions(Sema &S, Expr *OrigE, SourceLocation CC) {
- QualType T = OrigE->getType();
Expr *E = OrigE->IgnoreParenImpCasts();
if (E->isTypeDependent() || E->isValueDependent())
return;
+
+ QualType T = OrigE->getType();
+ // Check for conversion from an arithmetic type to a vector of arithmetic
+ // type elements. Warn if this results in truncation of each vector element.
+ if (isa<ExtVectorElementExpr>(E)) {
+ if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(OrigE))
+ if ((ICE->getCastKind() == CK_VectorSplat) &&
+ !T.isNull() && T->isExtVectorType())
+ T = cast<ExtVectorType>(T.getCanonicalType())->getElementType();
+ }
// For conditional operators, we analyze the arguments as if they
// were being fed directly into the output.