More rule enforcement of zero bitfields for ms_struct.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@130696 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/AST/ASTContext.h b/include/clang/AST/ASTContext.h
index 3ca3c3b..28ec8cf 100644
--- a/include/clang/AST/ASTContext.h
+++ b/include/clang/AST/ASTContext.h
@@ -402,6 +402,11 @@
bool ZeroBitfieldFollowsNonBitfield(const FieldDecl *FD,
const FieldDecl *LastFD) const;
+ /// ZeroBitfieldFollowsBitfield - return 'true" if 'FD' is a zero-length
+ /// bitfield which follows the bitfield 'LastFD'.
+ bool ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
+ const FieldDecl *LastFD) const;
+
// Access to the set of methods overridden by the given C++ method.
typedef CXXMethodVector::iterator overridden_cxx_method_iterator;
overridden_cxx_method_iterator
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index 1f4d9a3..8316ea6 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -543,6 +543,13 @@
}
+bool ASTContext::ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
+ const FieldDecl *LastFD) const {
+ return (FD->isBitField() && LastFD && LastFD->isBitField() &&
+ FD->getBitWidth()-> EvaluateAsInt(*this).getZExtValue() == 0);
+
+}
+
ASTContext::overridden_cxx_method_iterator
ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index e336dd7..b21ba9a 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -2059,7 +2059,8 @@
if (IsMsStruct) {
// Zero-length bitfields following non-bitfield members are ignored.
- if (getASTContext().ZeroBitfieldFollowsNonBitfield((*i), LastFD)) {
+ if (getASTContext().ZeroBitfieldFollowsNonBitfield((*i), LastFD) ||
+ getASTContext().ZeroBitfieldFollowsBitfield((*i), LastFD)) {
++i;
continue;
}
diff --git a/lib/AST/RecordLayoutBuilder.cpp b/lib/AST/RecordLayoutBuilder.cpp
index 4076557..0770e1f 100644
--- a/lib/AST/RecordLayoutBuilder.cpp
+++ b/lib/AST/RecordLayoutBuilder.cpp
@@ -582,6 +582,8 @@
CharUnits NonVirtualSize;
CharUnits NonVirtualAlignment;
+ CharUnits ZeroLengthBitfieldAlignment;
+
/// PrimaryBase - the primary base class (if one exists) of the class
/// we're laying out.
const CXXRecordDecl *PrimaryBase;
@@ -618,7 +620,8 @@
IsMac68kAlign(false), IsMsStruct(false),
UnfilledBitsInLastByte(0), MaxFieldAlignment(CharUnits::Zero()),
DataSize(0), NonVirtualSize(CharUnits::Zero()),
- NonVirtualAlignment(CharUnits::One()), PrimaryBase(0),
+ NonVirtualAlignment(CharUnits::One()),
+ ZeroLengthBitfieldAlignment(CharUnits::Zero()), PrimaryBase(0),
PrimaryBaseIsVirtual(false), FirstNearlyEmptyVBase(0) { }
void Layout(const RecordDecl *D);
@@ -1258,9 +1261,18 @@
for (RecordDecl::field_iterator Field = D->field_begin(),
FieldEnd = D->field_end(); Field != FieldEnd; ++Field) {
if (IsMsStruct) {
+ const FieldDecl *FD = (*Field);
+ if (Context.ZeroBitfieldFollowsBitfield(FD, LastFD)) {
+ // FIXME. Multiple zero bitfields may follow a bitfield.
+ // set ZeroLengthBitfieldAlignment to max. of its
+ // currrent and alignment of 'FD'.
+ std::pair<CharUnits, CharUnits> FieldInfo =
+ Context.getTypeInfoInChars(FD->getType());
+ ZeroLengthBitfieldAlignment = FieldInfo.second;
+ continue;
+ }
// Zero-length bitfields following non-bitfield members are
// ignored:
- const FieldDecl *FD = (*Field);
if (Context.ZeroBitfieldFollowsNonBitfield(FD, LastFD))
continue;
LastFD = FD;
@@ -1443,6 +1455,9 @@
Context.getTypeInfoInChars(D->getType());
FieldSize = FieldInfo.first;
FieldAlign = FieldInfo.second;
+ if (ZeroLengthBitfieldAlignment > FieldAlign)
+ FieldAlign = ZeroLengthBitfieldAlignment;
+ ZeroLengthBitfieldAlignment = CharUnits::Zero();
if (Context.getLangOptions().MSBitfields) {
// If MS bitfield layout is required, figure out what type is being
diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index 6ce49b5..f2e1c02 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -628,7 +628,8 @@
FieldDecl *field = *I;
if (IsMsStruct) {
// Zero-length bitfields following non-bitfield members are ignored
- if (CGM.getContext().ZeroBitfieldFollowsNonBitfield((field), LastFD)) {
+ if (CGM.getContext().ZeroBitfieldFollowsNonBitfield((field), LastFD) ||
+ CGM.getContext().ZeroBitfieldFollowsBitfield((field), LastFD)) {
--fieldNo;
continue;
}
diff --git a/lib/CodeGen/CGExprConstant.cpp b/lib/CodeGen/CGExprConstant.cpp
index 8054d4b..463b913 100644
--- a/lib/CodeGen/CGExprConstant.cpp
+++ b/lib/CodeGen/CGExprConstant.cpp
@@ -352,7 +352,8 @@
if (IsMsStruct) {
// Zero-length bitfields following non-bitfield members are
// ignored:
- if (CGM.getContext().ZeroBitfieldFollowsNonBitfield((*Field), LastFD)) {
+ if (CGM.getContext().ZeroBitfieldFollowsNonBitfield((*Field), LastFD) ||
+ CGM.getContext().ZeroBitfieldFollowsBitfield((*Field), LastFD)) {
--FieldNo;
continue;
}
diff --git a/lib/CodeGen/CGRecordLayoutBuilder.cpp b/lib/CodeGen/CGRecordLayoutBuilder.cpp
index 3d9fd88..a4ac390 100644
--- a/lib/CodeGen/CGRecordLayoutBuilder.cpp
+++ b/lib/CodeGen/CGRecordLayoutBuilder.cpp
@@ -753,7 +753,8 @@
// Zero-length bitfields following non-bitfield members are
// ignored:
const FieldDecl *FD = (*Field);
- if (Types.getContext().ZeroBitfieldFollowsNonBitfield(FD, LastFD)) {
+ if (Types.getContext().ZeroBitfieldFollowsNonBitfield(FD, LastFD) ||
+ Types.getContext().ZeroBitfieldFollowsBitfield(FD, LastFD)) {
--FieldNo;
continue;
}
@@ -996,7 +997,8 @@
if (IsMsStruct) {
// Zero-length bitfields following non-bitfield members are
// ignored:
- if (getContext().ZeroBitfieldFollowsNonBitfield(FD, LastFD)) {
+ if (getContext().ZeroBitfieldFollowsNonBitfield(FD, LastFD) ||
+ getContext().ZeroBitfieldFollowsBitfield(FD, LastFD)) {
--i;
continue;
}
diff --git a/test/CodeGen/ms_struct-bitfield.c b/test/CodeGen/ms_struct-bitfield.c
index e9bd1d3..a8f4c91 100644
--- a/test/CodeGen/ms_struct-bitfield.c
+++ b/test/CodeGen/ms_struct-bitfield.c
@@ -107,6 +107,13 @@
char :4;
} ATTR t9;
+struct
+{
+ char foo: 8;
+ long : 0;
+ char bar;
+} ATTR t10;
+
static int arr1[(sizeof(t1) == 2) -1];
static int arr2[(sizeof(t2) == 2) -1];
static int arr3[(sizeof(t3) == 2) -1];
@@ -116,6 +123,7 @@
static int arr7[(sizeof(t7) == 9) -1];
static int arr8[(sizeof(t8) == 0) -1];
static int arr9[(sizeof(t9) == 28) -1];
+static int arr10[(sizeof(t10) == 16) -1];
int main() {
return 0;