[cfe-commits] r130257 - in /cfe/trunk: lib/AST/RecordLayoutBuilder.cpp lib/CodeGen/CGRecordLayoutBuilder.cpp test/CodeGen/ms_struct-bitfield.c
Fariborz Jahanian
fjahanian at apple.com
Tue Apr 26 16:52:16 PDT 2011
Author: fjahanian
Date: Tue Apr 26 18:52:16 2011
New Revision: 130257
URL: http://llvm.org/viewvc/llvm-project?rev=130257&view=rev
Log:
With ms_struct attribut, Zero-length bitfields following
non-bitfield members are ignore. // rdar://8823265 wip
Added:
cfe/trunk/test/CodeGen/ms_struct-bitfield.c
Modified:
cfe/trunk/lib/AST/RecordLayoutBuilder.cpp
cfe/trunk/lib/CodeGen/CGRecordLayoutBuilder.cpp
Modified: cfe/trunk/lib/AST/RecordLayoutBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/RecordLayoutBuilder.cpp?rev=130257&r1=130256&r2=130257&view=diff
==============================================================================
--- cfe/trunk/lib/AST/RecordLayoutBuilder.cpp (original)
+++ cfe/trunk/lib/AST/RecordLayoutBuilder.cpp Tue Apr 26 18:52:16 2011
@@ -564,6 +564,8 @@
unsigned IsUnion : 1;
unsigned IsMac68kAlign : 1;
+
+ unsigned IsMsStruct : 1;
/// UnfilledBitsInLastByte - If the last field laid out was a bitfield,
/// this contains the number of bits in the last byte that can be used for
@@ -612,7 +614,8 @@
*EmptySubobjects)
: Context(Context), EmptySubobjects(EmptySubobjects), Size(0),
Alignment(CharUnits::One()), UnpackedAlignment(Alignment),
- Packed(false), IsUnion(false), IsMac68kAlign(false),
+ Packed(false), IsUnion(false),
+ IsMac68kAlign(false), IsMsStruct(false),
UnfilledBitsInLastByte(0), MaxFieldAlignment(CharUnits::Zero()),
DataSize(0), NonVirtualSize(CharUnits::Zero()),
NonVirtualAlignment(CharUnits::One()), PrimaryBase(0),
@@ -1148,6 +1151,8 @@
IsUnion = RD->isUnion();
Packed = D->hasAttr<PackedAttr>();
+
+ IsMsStruct = D->hasAttr<MsStructAttr>();
// mac68k alignment supersedes maximum field alignment and attribute aligned,
// and forces all structures to have 2-byte alignment. The IBM docs on it
@@ -1249,9 +1254,21 @@
void RecordLayoutBuilder::LayoutFields(const RecordDecl *D) {
// Layout each field, for now, just sequentially, respecting alignment. In
// the future, this will need to be tweakable by targets.
+ const FieldDecl *LastFD = 0;
for (RecordDecl::field_iterator Field = D->field_begin(),
- FieldEnd = D->field_end(); Field != FieldEnd; ++Field)
+ FieldEnd = D->field_end(); Field != FieldEnd; ++Field) {
+ if (IsMsStruct) {
+ // Zero-length bitfields following non-bitfield members are
+ // ignored:
+ const FieldDecl *FD = (*Field);
+ if (FD->isBitField() && LastFD && !LastFD->isBitField() &&
+ FD->getBitWidth()->EvaluateAsInt(Context).getZExtValue() == 0) {
+ continue;
+ }
+ LastFD = FD;
+ }
LayoutField(*Field);
+ }
}
void RecordLayoutBuilder::LayoutWideBitField(uint64_t FieldSize,
Modified: cfe/trunk/lib/CodeGen/CGRecordLayoutBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGRecordLayoutBuilder.cpp?rev=130257&r1=130256&r2=130257&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGRecordLayoutBuilder.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGRecordLayoutBuilder.cpp Tue Apr 26 18:52:16 2011
@@ -77,6 +77,9 @@
/// Packed - Whether the resulting LLVM struct will be packed or not.
bool Packed;
+
+ /// IsMsStruct - Whether ms_struct is in effect or not
+ bool IsMsStruct;
private:
CodeGenTypes &Types;
@@ -184,7 +187,8 @@
CGRecordLayoutBuilder(CodeGenTypes &Types)
: BaseSubobjectType(0),
IsZeroInitializable(true), IsZeroInitializableAsBase(true),
- Packed(false), Types(Types), BitsAvailableInLastField(0) { }
+ Packed(false), IsMsStruct(false),
+ Types(Types), BitsAvailableInLastField(0) { }
/// Layout - Will layout a RecordDecl.
void Layout(const RecordDecl *D);
@@ -195,6 +199,8 @@
void CGRecordLayoutBuilder::Layout(const RecordDecl *D) {
Alignment = Types.getContext().getASTRecordLayout(D).getAlignment();
Packed = D->hasAttr<PackedAttr>();
+
+ IsMsStruct = D->hasAttr<MsStructAttr>();
if (D->isUnion()) {
LayoutUnion(D);
@@ -739,9 +745,24 @@
LayoutNonVirtualBases(RD, Layout);
unsigned FieldNo = 0;
-
+ const FieldDecl *LastFD = 0;
+
for (RecordDecl::field_iterator Field = D->field_begin(),
FieldEnd = D->field_end(); Field != FieldEnd; ++Field, ++FieldNo) {
+ if (IsMsStruct) {
+ // Zero-length bitfields following non-bitfield members are
+ // ignored:
+ const FieldDecl *FD = (*Field);
+ // FIXME. Refactor into common code as it is used in several places.
+ if (FD->isBitField() && LastFD && !LastFD->isBitField() &&
+ FD->getBitWidth()->
+ EvaluateAsInt(Types.getContext()).getZExtValue() == 0) {
+ --FieldNo;
+ continue;
+ }
+ LastFD = FD;
+ }
+
if (!LayoutField(*Field, Layout.getFieldOffset(FieldNo))) {
assert(!Packed &&
"Could not layout fields even with a packed LLVM struct!");
@@ -960,6 +981,8 @@
const ASTRecordLayout &AST_RL = getContext().getASTRecordLayout(D);
RecordDecl::field_iterator it = D->field_begin();
+ const FieldDecl *LastFD = 0;
+ bool IsMsStruct = D->hasAttr<MsStructAttr>();
for (unsigned i = 0, e = AST_RL.getFieldCount(); i != e; ++i, ++it) {
const FieldDecl *FD = *it;
@@ -969,13 +992,28 @@
unsigned FieldNo = RL->getLLVMFieldNo(FD);
assert(AST_RL.getFieldOffset(i) == SL->getElementOffsetInBits(FieldNo) &&
"Invalid field offset!");
+ LastFD = FD;
continue;
}
+ if (IsMsStruct) {
+ // Zero-length bitfields following non-bitfield members are
+ // ignored:
+ if (FD->isBitField() && LastFD && !LastFD->isBitField() &&
+ FD->getBitWidth()->
+ EvaluateAsInt(getContext()).getZExtValue() == 0) {
+ --i;
+ continue;
+ }
+ LastFD = FD;
+ }
+
// Ignore unnamed bit-fields.
- if (!FD->getDeclName())
+ if (!FD->getDeclName()) {
+ LastFD = FD;
continue;
-
+ }
+
const CGBitFieldInfo &Info = RL->getBitFieldInfo(FD);
for (unsigned i = 0, e = Info.getNumComponents(); i != e; ++i) {
const CGBitFieldInfo::AccessInfo &AI = Info.getComponent(i);
Added: cfe/trunk/test/CodeGen/ms_struct-bitfield.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/ms_struct-bitfield.c?rev=130257&view=auto
==============================================================================
--- cfe/trunk/test/CodeGen/ms_struct-bitfield.c (added)
+++ cfe/trunk/test/CodeGen/ms_struct-bitfield.c Tue Apr 26 18:52:16 2011
@@ -0,0 +1,123 @@
+// RUN: %clang_cc1 -emit-llvm-only -triple x86_64-apple-darwin9 %s
+// rdar://8823265
+
+#define ATTR __attribute__((__ms_struct__))
+
+struct
+{
+ char foo;
+ long : 0;
+ char bar;
+} ATTR t1;
+
+struct
+{
+ char foo;
+ long : 0;
+ char : 0;
+ int : 0;
+ char bar;
+} ATTR t2;
+
+struct
+{
+ char foo;
+ long : 0;
+ char : 0;
+ int : 0;
+ char bar;
+ long : 0;
+ char : 0;
+} ATTR t3;
+
+struct
+{
+ long : 0;
+ char bar;
+} ATTR t4;
+
+struct
+{
+ long : 0;
+ long : 0;
+ char : 0;
+ char bar;
+} ATTR t5;
+
+struct
+{
+ long : 0;
+ long : 0;
+ char : 0;
+ char bar;
+} ATTR t6;
+
+struct
+{
+ char foo;
+ long : 0;
+ int : 0;
+ char bar;
+ char bar1;
+ long : 0;
+ char bar2;
+ char bar3;
+ char : 0;
+ char bar4;
+ char bar5;
+ char : 0;
+ char bar6;
+ char bar7;
+} ATTR t7;
+
+struct
+{
+ long : 0;
+ long : 0;
+ char : 0;
+} ATTR t8;
+
+struct
+{
+ char foo;
+ long : 0;
+ int : 0;
+ char bar;
+ char bar1;
+ long : 0;
+ char bar2;
+ char bar3;
+ char : 0;
+ char bar4;
+ char bar5;
+ char : 0;
+ char bar6;
+ char bar7;
+ int i1;
+ char : 0;
+ long : 0;
+ char :4;
+ char bar8;
+ char : 0;
+ char bar9;
+ char bar10;
+ int i2;
+ char : 0;
+ long : 0;
+ char :4;
+} ATTR t9;
+
+static int arr1[(sizeof(t1) == 2) -1];
+static int arr2[(sizeof(t2) == 2) -1];
+static int arr3[(sizeof(t3) == 2) -1];
+static int arr4[(sizeof(t4) == 1) -1];
+static int arr5[(sizeof(t5) == 1) -1];
+static int arr6[(sizeof(t6) == 1) -1];
+static int arr7[(sizeof(t7) == 9) -1];
+static int arr8[(sizeof(t8) == 0) -1];
+static int arr9[(sizeof(t9) == 28) -1];
+
+int main() {
+ return 0;
+}
+
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