[llvm-branch-commits] [clang] 55488bd - CGExpr - EmitMatrixSubscriptExpr - fix getAs<> null-dereference static analyzer warning. NFCI.

[Simon Pilgrim via llvm-branch-commits]

Author: Simon Pilgrim
Date: 2021-01-05T17:08:11Z
New Revision: 55488bd3cd1a468941e26ad4cf94f2bad887fc02

URL: https://github.com/llvm/llvm-project/commit/55488bd3cd1a468941e26ad4cf94f2bad887fc02
DIFF: https://github.com/llvm/llvm-project/commit/55488bd3cd1a468941e26ad4cf94f2bad887fc02.diff

LOG: CGExpr - EmitMatrixSubscriptExpr - fix getAs<> null-dereference static analyzer warning. NFCI.

getAs<> can return null if the cast is invalid, which can lead to null pointer deferences. Use castAs<> instead which will assert that the cast is valid.

Added: 
    

Modified: 
    clang/lib/CodeGen/CGExpr.cpp

Removed: 
    


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diff  --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index 3013fffcbf6d..a3f90449bb4c 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -3858,7 +3858,7 @@ LValue CodeGenFunction::EmitMatrixSubscriptExpr(const MatrixSubscriptExpr *E) {
   llvm::Value *ColIdx = EmitScalarExpr(E->getColumnIdx());
   llvm::Value *NumRows = Builder.getIntN(
       RowIdx->getType()->getScalarSizeInBits(),
-      E->getBase()->getType()->getAs<ConstantMatrixType>()->getNumRows());
+      E->getBase()->getType()->castAs<ConstantMatrixType>()->getNumRows());
   llvm::Value *FinalIdx =
       Builder.CreateAdd(Builder.CreateMul(ColIdx, NumRows), RowIdx);
   return LValue::MakeMatrixElt(