From: Arnold Schwaighofer <aschwaighofer@apple.com>
Date: Thu, 13 Oct 2016 19:19:37 +0000 (+0000)
Subject: Swift Calling Convention: Fix out of bounds access
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=6ea1c6c267e6a543c663599798770c1df09c17c5;p=clang

Swift Calling Convention: Fix out of bounds access

Use iterator instead of address of element in vector

It is not valid to access one after the last element.

rdar://28759508

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@284150 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/SwiftCallingConv.cpp b/lib/CodeGen/SwiftCallingConv.cpp
index a79ddf94bc..1629c44365 100644
--- a/lib/CodeGen/SwiftCallingConv.cpp
+++ b/lib/CodeGen/SwiftCallingConv.cpp
@@ -384,7 +384,7 @@ void SwiftAggLowering::splitVectorEntry(unsigned index) {
   auto eltTy = split.first;
   CharUnits eltSize = getTypeStoreSize(CGM, eltTy);
   auto numElts = split.second;
-  Entries.insert(&Entries[index + 1], numElts - 1, StorageEntry());
+  Entries.insert(Entries.begin() + index + 1, numElts - 1, StorageEntry());
 
   CharUnits begin = Entries[index].Begin;
   for (unsigned i = 0; i != numElts; ++i) {
diff --git a/test/CodeGen/64bit-swiftcall.c b/test/CodeGen/64bit-swiftcall.c
index f5e63fe4d8..6167436157 100644
--- a/test/CodeGen/64bit-swiftcall.c
+++ b/test/CodeGen/64bit-swiftcall.c
@@ -694,3 +694,22 @@ typedef struct {
 TEST(struct_l5)
 // CHECK: define swiftcc void @return_struct_l5([[STRUCT5:%.*]]* noalias sret
 // CHECK: define swiftcc void @take_struct_l5([[STRUCT5]]*
+
+
+// Don't crash.
+typedef union {
+int4 v[2];
+struct {
+  int LSW;
+  int d7;
+  int d6;
+  int d5;
+  int d4;
+  int d3;
+  int d2;
+  int MSW;
+} s;
+} union_het_vecint;
+TEST(union_het_vecint)
+// CHECK: define swiftcc void @return_union_het_vecint([[UNION:%.*]]* noalias sret
+// CHECK: define swiftcc void @take_union_het_vecint([[UNION]]*