Fix invalid shufflevector operands
This patch fixes bug 23800 ( https://llvm.org/bugs/show_bug.cgi?id=23800#c2 ). There existed a case where the index operand from extractelement was directly used to create a shufflevector mask. Since the index can be of any integral type but the mask must only contain 32 bit integers a 64 bit index operand led to an assertion error later on.
Committed on behalf of mpflanzer (Moritz Pflanzer)
Differential Revision: http://reviews.llvm.org/D10838
llvm-svn: 243851
diff --git a/clang/lib/CodeGen/CGExprScalar.cpp b/clang/lib/CodeGen/CGExprScalar.cpp
index f3e4836..195c7a4 100644
--- a/clang/lib/CodeGen/CGExprScalar.cpp
+++ b/clang/lib/CodeGen/CGExprScalar.cpp
@@ -1162,6 +1162,16 @@
return llvm::ConstantInt::get(I32Ty, Off+MV);
}
+static llvm::Constant *getAsInt32(llvm::ConstantInt *C, llvm::Type *I32Ty) {
+ if (C->getBitWidth() != 32) {
+ assert(llvm::ConstantInt::isValueValidForType(I32Ty,
+ C->getZExtValue()) &&
+ "Index operand too large for shufflevector mask!");
+ return llvm::ConstantInt::get(I32Ty, C->getZExtValue());
+ }
+ return C;
+}
+
Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) {
bool Ignore = TestAndClearIgnoreResultAssign();
(void)Ignore;
@@ -1212,7 +1222,8 @@
Value *LHS = nullptr, *RHS = nullptr;
if (CurIdx == 0) {
// insert into undef -> shuffle (src, undef)
- Args.push_back(C);
+ // shufflemask must use an i32
+ Args.push_back(getAsInt32(C, CGF.Int32Ty));
Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
LHS = EI->getVectorOperand();