From: George Karpenkov <ekarpenkov@apple.com>
Date: Wed, 7 Mar 2018 22:20:39 +0000 (+0000)
Subject: [analyzer] [PointerArithChecker] do not warn on indexes into vector types
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=9062e07a82f72a8bf3f55701a6b1f26186eb74a0;p=clang

[analyzer] [PointerArithChecker] do not warn on indexes into vector types

rdar://35041502

Differential Revision: https://reviews.llvm.org/D44172

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@326952 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/StaticAnalyzer/Checkers/PointerArithChecker.cpp b/lib/StaticAnalyzer/Checkers/PointerArithChecker.cpp
index 4c4a8e3f0d..63f82b275b 100644
--- a/lib/StaticAnalyzer/Checkers/PointerArithChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/PointerArithChecker.cpp
@@ -308,6 +308,10 @@ void PointerArithChecker::checkPreStmt(const ArraySubscriptExpr *SubsExpr,
   // Indexing with 0 is OK.
   if (Idx.isZeroConstant())
     return;
+
+  // Indexing vector-type expressions is also OK.
+  if (SubsExpr->getBase()->getType()->isVectorType())
+    return;
   reportPointerArithMisuse(SubsExpr->getBase(), C);
 }
 
diff --git a/test/Analysis/ptr-arith.c b/test/Analysis/ptr-arith.c
index 93cb4ee9a6..804759a32d 100644
--- a/test/Analysis/ptr-arith.c
+++ b/test/Analysis/ptr-arith.c
@@ -347,3 +347,9 @@ void test_no_crash_on_pointer_to_label() {
   a[0] = 0;
 label:;
 }
+
+typedef __attribute__((__ext_vector_type__(2))) float simd_float2;
+float test_nowarning_on_vector_deref() {
+  simd_float2 x = {0, 1};
+  return x[1]; // no-warning
+}