[cfe-commits] r131188 - in /cfe/trunk: lib/AST/RecordLayoutBuilder.cpp test/CodeGen/ms_struct-pack.c
Fariborz Jahanian
fjahanian at apple.com
Wed May 11 09:58:31 PDT 2011
Author: fjahanian
Date: Wed May 11 11:58:31 2011
New Revision: 131188
URL: http://llvm.org/viewvc/llvm-project?rev=131188&view=rev
Log:
Implenment #pack pragma and ms_struct attribute layout.
Concludes // radar://8823265.
Modified:
cfe/trunk/lib/AST/RecordLayoutBuilder.cpp
cfe/trunk/test/CodeGen/ms_struct-pack.c
Modified: cfe/trunk/lib/AST/RecordLayoutBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/RecordLayoutBuilder.cpp?rev=131188&r1=131187&r2=131188&view=diff
==============================================================================
--- cfe/trunk/lib/AST/RecordLayoutBuilder.cpp (original)
+++ cfe/trunk/lib/AST/RecordLayoutBuilder.cpp Wed May 11 11:58:31 2011
@@ -1259,6 +1259,7 @@
// the future, this will need to be tweakable by targets.
const FieldDecl *LastFD = 0;
ZeroLengthBitfield = 0;
+ unsigned RemainingInAlignment = 0;
for (RecordDecl::field_iterator Field = D->field_begin(),
FieldEnd = D->field_end(); Field != FieldEnd; ++Field) {
if (IsMsStruct) {
@@ -1295,17 +1296,33 @@
// This check is needed for 'long long' in -m32 mode.
if (TypeSizeLastFD > FieldAlignLastFD)
FieldAlignLastFD = TypeSizeLastFD;
+
if (TypeSizeLastFD != TypeSize) {
+ if (RemainingInAlignment &&
+ LastFD && LastFD->isBitField() &&
+ LastFD->getBitWidth()->EvaluateAsInt(Context).getZExtValue()) {
+ // If previous field was a bitfield with some remaining unfilled
+ // bits, pad the field so current field starts on its type boundary.
+ uint64_t FieldOffset =
+ getDataSizeInBits() - UnfilledBitsInLastByte;
+ uint64_t NewSizeInBits = RemainingInAlignment + FieldOffset;
+ setDataSize(llvm::RoundUpToAlignment(NewSizeInBits,
+ Context.Target.getCharAlign()));
+ setSize(std::max(getSizeInBits(), getDataSizeInBits()));
+ RemainingInAlignment = 0;
+ }
+
uint64_t UnpaddedFieldOffset =
getDataSizeInBits() - UnfilledBitsInLastByte;
FieldAlign = std::max(FieldAlign, FieldAlignLastFD);
+
// The maximum field alignment overrides the aligned attribute.
if (!MaxFieldAlignment.isZero()) {
unsigned MaxFieldAlignmentInBits =
Context.toBits(MaxFieldAlignment);
FieldAlign = std::min(FieldAlign, MaxFieldAlignmentInBits);
}
-
+
uint64_t NewSizeInBits =
llvm::RoundUpToAlignment(UnpaddedFieldOffset, FieldAlign);
setDataSize(llvm::RoundUpToAlignment(NewSizeInBits,
@@ -1313,11 +1330,40 @@
UnfilledBitsInLastByte = getDataSizeInBits() - NewSizeInBits;
setSize(std::max(getSizeInBits(), getDataSizeInBits()));
}
+ if (FD->isBitField()) {
+ uint64_t FieldSize =
+ FD->getBitWidth()->EvaluateAsInt(Context).getZExtValue();
+ assert (FieldSize > 0 && "LayoutFields - ms_struct layout");
+ if (RemainingInAlignment < FieldSize)
+ RemainingInAlignment = TypeSize - FieldSize;
+ else
+ RemainingInAlignment -= FieldSize;
+ }
+ }
+ else if (FD->isBitField()) {
+ uint64_t FieldSize =
+ FD->getBitWidth()->EvaluateAsInt(Context).getZExtValue();
+ std::pair<uint64_t, unsigned> FieldInfo =
+ Context.getTypeInfo(FD->getType());
+ uint64_t TypeSize = FieldInfo.first;
+ RemainingInAlignment = TypeSize - FieldSize;
}
LastFD = FD;
}
LayoutField(*Field);
}
+ if (IsMsStruct && RemainingInAlignment &&
+ LastFD && LastFD->isBitField() &&
+ LastFD->getBitWidth()->EvaluateAsInt(Context).getZExtValue()) {
+ // If we ended a bitfield before the full length of the type then
+ // pad the struct out to the full length of the last type.
+ uint64_t FieldOffset =
+ getDataSizeInBits() - UnfilledBitsInLastByte;
+ uint64_t NewSizeInBits = RemainingInAlignment + FieldOffset;
+ setDataSize(llvm::RoundUpToAlignment(NewSizeInBits,
+ Context.Target.getCharAlign()));
+ setSize(std::max(getSizeInBits(), getDataSizeInBits()));
+ }
}
void RecordLayoutBuilder::LayoutWideBitField(uint64_t FieldSize,
Modified: cfe/trunk/test/CodeGen/ms_struct-pack.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/ms_struct-pack.c?rev=131188&r1=131187&r2=131188&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/ms_struct-pack.c (original)
+++ cfe/trunk/test/CodeGen/ms_struct-pack.c Wed May 11 11:58:31 2011
@@ -2,6 +2,36 @@
// rdar://8823265
#pragma pack(1)
+struct _one_ms {
+ short m:9; // size is 2
+ int q:27; // size is 6
+ short w:13; // size is 8
+ short e:3; // size is 8
+ char r:4; // size is 9
+ char t:7; // size is 10
+ short y:16; // size is 12
+ short u:1; // size is 14
+ char i:2; // size is 15
+ int a; // size is 19
+ char o:6; // size is 20
+ char s:2; // size is 20
+ short d:10; // size is 22
+ short f:4; // size is 22
+ char b; // size is 23
+ char g:1; // size is 24
+ short h:13; // size is 26
+ char j:8; // size is 27
+ char k:5; // size is 28
+ char c; // size is 29
+ int l:28; // size is 33
+ char z:7; // size is 34
+ int x:20; // size is 38
+} __attribute__((__ms_struct__));
+typedef struct _one_ms one_ms;
+
+static int a1[(sizeof(one_ms) == 38) - 1];
+
+#pragma pack(2)
struct _two_ms {
short m:9; // size is 2
int q:27; // size is 6
@@ -10,25 +40,86 @@
char r:4; // size is 9
char t:7; // size is 10
short y:16; // size is 12
-// clang and gcc start differing here. clang seems to follow the rules.
- short u:1; // size is clang: 13 gcc:14
- char i:2; // size is 14
- int a; // size is 18
- char o:6; // size is 19
- char s:2; // size is 19
- short d:10; // size is 21
- short f:4; // size is 21
- char b; // size is 22
- char g:1; // size is 23
- short h:13; // size is 25
- char j:8; // size is 26
- char k:5; // size is 27
- char c; // size is 28
- int l:28; // size is 32
- char z:7; // size is 33
- int x:20; // size is clang: 36 gcc:38
- } __attribute__((__ms_struct__));
+ short u:1; // size is 14
+ char i:2; // size is 15
+ int a; // size is 19
+ char o:6; // size is 20
+ char s:2; // size is 20
+ short d:10; // size is 22
+ short f:4; // size is 22
+ char b; // size is 23
+ char g:1; // size is 24
+ short h:13; // size is 26
+ char j:8; // size is 27
+ char k:5; // size is 28
+ char c; // size is 29
+ int l:28; // size is 33
+ char z:7; // size is 34
+ int x:20; // size is 38
+} __attribute__((__ms_struct__));
+
typedef struct _two_ms two_ms;
-// gcc says size is 38, but its does not seem right!
-static int a1[(sizeof(two_ms) == 36) - 1];
+static int a2[(sizeof(two_ms) == 42) - 1];
+
+#pragma pack(4)
+struct _four_ms {
+ short m:9; // size is 2
+ int q:27; // size is 6
+ short w:13; // size is 8
+ short e:3; // size is 8
+ char r:4; // size is 9
+ char t:7; // size is 10
+ short y:16; // size is 12
+ short u:1; // size is 14
+ char i:2; // size is 15
+ int a; // size is 19
+ char o:6; // size is 20
+ char s:2; // size is 20
+ short d:10; // size is 22
+ short f:4; // size is 22
+ char b; // size is 23
+ char g:1; // size is 24
+ short h:13; // size is 26
+ char j:8; // size is 27
+ char k:5; // size is 28
+ char c; // size is 29
+ int l:28; // size is 33
+ char z:7; // size is 34
+ int x:20; // size is 38
+} __attribute__((__ms_struct__));
+typedef struct _four_ms four_ms;
+
+static int a4[(sizeof(four_ms) == 48) - 1];
+
+#pragma pack(8)
+struct _eight_ms {
+ short m:9; // size is 2
+ int q:27; // size is 6
+ short w:13; // size is 8
+ short e:3; // size is 8
+ char r:4; // size is 9
+ char t:7; // size is 10
+ short y:16; // size is 12
+ short u:1; // size is 14
+ char i:2; // size is 15
+ int a; // size is 19
+ char o:6; // size is 20
+ char s:2; // size is 20
+ short d:10; // size is 22
+ short f:4; // size is 22
+ char b; // size is 23
+ char g:1; // size is 24
+ short h:13; // size is 26
+ char j:8; // size is 27
+ char k:5; // size is 28
+ char c; // size is 29
+ int l:28; // size is 33
+ char z:7; // size is 34
+ int x:20; // size is 38
+} __attribute__((__ms_struct__));
+
+typedef struct _eight_ms eight_ms;
+
+static int a8[(sizeof(eight_ms) == 48) - 1];
+
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