[cfe-commits] r82682 - in /cfe/trunk: lib/AST/RecordLayoutBuilder.cpp test/SemaCXX/empty-class-layout.cpp
Anders Carlsson
andersca at mac.com
Wed Sep 23 22:21:32 PDT 2009
Author: andersca
Date: Thu Sep 24 00:21:31 2009
New Revision: 82682
URL: http://llvm.org/viewvc/llvm-project?rev=82682&view=rev
Log:
More improvements with laying out empty bases.
Modified:
cfe/trunk/lib/AST/RecordLayoutBuilder.cpp
cfe/trunk/test/SemaCXX/empty-class-layout.cpp
Modified: cfe/trunk/lib/AST/RecordLayoutBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/RecordLayoutBuilder.cpp?rev=82682&r1=82681&r2=82682&view=diff
==============================================================================
--- cfe/trunk/lib/AST/RecordLayoutBuilder.cpp (original)
+++ cfe/trunk/lib/AST/RecordLayoutBuilder.cpp Thu Sep 24 00:21:31 2009
@@ -230,7 +230,25 @@
return false;
}
- // FIXME: Bases and fields.
+ const ASTRecordLayout &Info = Ctx.getASTRecordLayout(RD);
+
+ // Check bases.
+ for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
+ E = RD->bases_end(); I != E; ++I) {
+ if (I->isVirtual())
+ continue;
+
+ const CXXRecordDecl *Base =
+ cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
+
+ uint64_t BaseClassOffset = Info.getBaseClassOffset(Base);
+
+ if (!canPlaceRecordAtOffset(Base, Offset + BaseClassOffset))
+ return false;
+ }
+
+ // FIXME: fields.
+ // FIXME: virtual bases.
return true;
}
@@ -238,8 +256,23 @@
uint64_t Offset) {
if (RD->isEmpty())
EmptyClassOffsets.insert(std::make_pair(Offset, RD));
+
+ const ASTRecordLayout &Info = Ctx.getASTRecordLayout(RD);
+
+ // Update bases.
+ for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
+ E = RD->bases_end(); I != E; ++I) {
+ if (I->isVirtual())
+ continue;
- // FIXME: Update bases and fields.
+ const CXXRecordDecl *Base =
+ cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
+
+ uint64_t BaseClassOffset = Info.getBaseClassOffset(Base);
+ UpdateEmptyClassOffsets(Base, Offset + BaseClassOffset);
+ }
+
+ // FIXME: Update fields and virtual bases.
}
uint64_t ASTRecordLayoutBuilder::LayoutBase(const CXXRecordDecl *RD) {
@@ -248,25 +281,35 @@
// If we have an empty base class, try to place it at offset 0.
if (RD->isEmpty() && canPlaceRecordAtOffset(RD, 0)) {
// We were able to place the class at offset 0.
- // Since the base is empty we don't have to update the size or alignment.
UpdateEmptyClassOffsets(RD, 0);
-
+
+ Size = std::max(Size, BaseInfo.getNonVirtualSize());
+
return 0;
}
unsigned BaseAlign = BaseInfo.getNonVirtualAlign();
+
// Round up the current record size to the base's alignment boundary.
uint64_t Offset = llvm::RoundUpToAlignment(Size, BaseAlign);
- // Reserve space for this base.
- Size = Offset + BaseInfo.getNonVirtualSize();
-
+ // Try to place the base.
+ while (true) {
+ if (canPlaceRecordAtOffset(RD, Offset))
+ break;
+
+ Offset += BaseAlign;
+ }
+
// Remember the next available offset.
- NextOffset = Size;
+ NextOffset = Offset + BaseInfo.getNonVirtualSize();
+
+ Size = std::max(Size, NextOffset);
// Remember max struct/class alignment.
UpdateAlignment(BaseAlign);
-
+
+ UpdateEmptyClassOffsets(RD, Offset);
return Offset;
}
Modified: cfe/trunk/test/SemaCXX/empty-class-layout.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/empty-class-layout.cpp?rev=82682&r1=82681&r2=82682&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/empty-class-layout.cpp (original)
+++ cfe/trunk/test/SemaCXX/empty-class-layout.cpp Thu Sep 24 00:21:31 2009
@@ -10,3 +10,10 @@
struct C : A, B { };
SA(2, sizeof(C) == 4);
+
+struct D { };
+struct E : D { };
+struct F : E { };
+
+struct G : E, F { };
+SA(3, sizeof(G) == 2);
More information about the cfe-commits
mailing list