From: Chris Lattner <sabre@nondot.org>
Date: Thu, 29 Jul 2010 17:34:39 +0000 (+0000)
Subject: handle a case where we could access off the end of a function
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=9e45a3de3f462785a86bba77dee168ab354d9704;p=clang

handle a case where we could access off the end of a function
that Eli pointed out, rdar://8249586


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@109762 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/TargetInfo.cpp b/lib/CodeGen/TargetInfo.cpp
index 0d8d3a9dff..67f8a20144 100644
--- a/lib/CodeGen/TargetInfo.cpp
+++ b/lib/CodeGen/TargetInfo.cpp
@@ -1358,18 +1358,15 @@ Get8ByteTypeAtOffset(const llvm::Type *IRType, unsigned IROffset,
   
   // Okay, we don't have any better idea of what to pass, so we pass this in an
   // integer register that isn't too big to fit the rest of the struct.
-  uint64_t TySizeInBytes =
-    getContext().getTypeSizeInChars(SourceTy).getQuantity();
+  unsigned TySizeInBytes =
+    (unsigned)getContext().getTypeSizeInChars(SourceTy).getQuantity();
 
+  assert(TySizeInBytes != SourceOffset && "Empty field?");
+  
   // It is always safe to classify this as an integer type up to i64 that
   // isn't larger than the structure.
-  switch (unsigned(TySizeInBytes-SourceOffset)) {
-  case 1:  return llvm::Type::getInt8Ty(getVMContext());
-  case 2:  return llvm::Type::getInt16Ty(getVMContext());
-  case 3:
-  case 4:  return llvm::Type::getInt32Ty(getVMContext());
-  default: return llvm::Type::getInt64Ty(getVMContext());
-  }  
+  return llvm::IntegerType::get(getVMContext(),
+                                std::min(TySizeInBytes-SourceOffset, 8U)*8);
 }
 
 ABIArgInfo X86_64ABIInfo::
diff --git a/test/CodeGen/x86_64-arguments.c b/test/CodeGen/x86_64-arguments.c
index 3bbbc5455d..1243dd7239 100644
--- a/test/CodeGen/x86_64-arguments.c
+++ b/test/CodeGen/x86_64-arguments.c
@@ -204,3 +204,9 @@ struct f29a {
 void f29a(struct f29a A) {
   // CHECK: define void @f29a(double %A.coerce0, i32 %A.coerce1)
 }
+
+// rdar://8249586
+struct S0 { char f0[8]; char f2; char f3; char f4; };
+void f30(struct S0 p_4) {
+  // CHECK: define void @f30(i64 %p_4.coerce0, i24 %p_4.coerce1)
+}