From f079b735d876f75e67b8dcc6980d0b742903ce0d Mon Sep 17 00:00:00 2001 From: Ken Dyck Date: Mon, 28 Feb 2011 02:01:38 +0000 Subject: [PATCH] Retry r126357. Use CharUnits for the Size and DataSize calculations when they are known to be exact multiples of the width of the char type. Add a test case to CodeGen/union.c that would have caught the problem with the previous attempt. No change in functionality intended. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@126628 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/AST/RecordLayoutBuilder.cpp | 63 ++++++++++++++------------------- test/CodeGen/union.c | 2 ++ 2 files changed, 29 insertions(+), 36 deletions(-) diff --git a/lib/AST/RecordLayoutBuilder.cpp b/lib/AST/RecordLayoutBuilder.cpp index 4ed031f974..bcaa1f47d6 100644 --- a/lib/AST/RecordLayoutBuilder.cpp +++ b/lib/AST/RecordLayoutBuilder.cpp @@ -815,8 +815,8 @@ void RecordLayoutBuilder::DeterminePrimaryBase(const CXXRecordDecl *RD) { assert(DataSize == 0 && "Vtable pointer must be at offset zero!"); // Update the size. - setSize(getSizeInBits() + GetVirtualPointersSize(RD)); - setDataSize(getSizeInBits()); + setSize(getSize() + Context.toCharUnitsFromBits(GetVirtualPointersSize(RD))); + setDataSize(getSize()); CharUnits UnpackedBaseAlign = Context.toCharUnitsFromBits(Context.Target.getPointerAlign(0)); @@ -1108,8 +1108,7 @@ CharUnits RecordLayoutBuilder::LayoutBase(const BaseSubobjectInfo *Base) { // If we have an empty base class, try to place it at offset 0. if (Base->Class->isEmpty() && EmptySubobjects->CanPlaceBaseAtOffset(Base, CharUnits::Zero())) { - uint64_t RecordSizeInBits = Context.toBits(Layout.getSize()); - setSize(std::max(getSizeInBits(), RecordSizeInBits)); + setSize(std::max(getSize(), Layout.getSize())); return CharUnits::Zero(); } @@ -1124,27 +1123,24 @@ CharUnits RecordLayoutBuilder::LayoutBase(const BaseSubobjectInfo *Base) { } // Round up the current record size to the base's alignment boundary. - uint64_t Offset = - llvm::RoundUpToAlignment(getDataSizeInBits(), Context.toBits(BaseAlign)); + CharUnits Offset = getDataSize().RoundUpToAlignment(BaseAlign); // Try to place the base. - while (!EmptySubobjects->CanPlaceBaseAtOffset(Base, - Context.toCharUnitsFromBits(Offset))) - Offset += Context.toBits(BaseAlign); + while (!EmptySubobjects->CanPlaceBaseAtOffset(Base, Offset)) + Offset += BaseAlign; if (!Base->Class->isEmpty()) { // Update the data size. - setDataSize(Offset + Context.toBits(Layout.getNonVirtualSize())); + setDataSize(Offset + Layout.getNonVirtualSize()); - setSize(std::max(getSizeInBits(), getDataSizeInBits())); + setSize(std::max(getSize(), getDataSize())); } else - setSize(std::max(getSizeInBits(), - Offset + Context.toBits(Layout.getSize()))); + setSize(std::max(getSize(), Offset + Layout.getSize())); // Remember max struct/class alignment. UpdateAlignment(BaseAlign, UnpackedBaseAlign); - return Context.toCharUnitsFromBits(Offset); + return Offset; } void RecordLayoutBuilder::InitializeLayout(const Decl *D) { @@ -1233,7 +1229,7 @@ void RecordLayoutBuilder::Layout(const ObjCInterfaceDecl *D) { // We start laying out ivars not at the end of the superclass // structure, but at the next byte following the last field. setSize(SL.getDataSize()); - setDataSize(getSizeInBits()); + setDataSize(getSize()); } InitializeLayout(D); @@ -1487,7 +1483,7 @@ void RecordLayoutBuilder::LayoutField(const FieldDecl *D) { if (IsUnion) setSize(std::max(getSizeInBits(), FieldSizeInBits)); else - setSize(Context.toBits(FieldOffset) + FieldSizeInBits); + setSize(FieldOffset + FieldSize); // Update the data size. setDataSize(getSizeInBits()); @@ -1504,17 +1500,18 @@ void RecordLayoutBuilder::FinishLayout(const NamedDecl *D) { // which is not empty but of size 0; such as having fields of // array of zero-length, remains of Size 0 if (RD->isEmpty()) - setSize(8); + setSize(CharUnits::One()); } else - setSize(8); + setSize(CharUnits::One()); } // Finally, round the size of the record up to the alignment of the // record itself. uint64_t UnpaddedSize = getSizeInBits() - UnfilledBitsInLastByte; - uint64_t UnpackedSize = + uint64_t UnpackedSizeInBits = llvm::RoundUpToAlignment(getSizeInBits(), Context.toBits(UnpackedAlignment)); + CharUnits UnpackedSize = Context.toCharUnitsFromBits(UnpackedSizeInBits); setSize(llvm::RoundUpToAlignment(getSizeInBits(), Context.toBits(Alignment))); unsigned CharBitNum = Context.Target.getCharWidth(); @@ -1536,7 +1533,7 @@ void RecordLayoutBuilder::FinishLayout(const NamedDecl *D) { // Warn if we packed it unnecessarily. If the alignment is 1 byte don't // bother since there won't be alignment issues. if (Packed && UnpackedAlignment > CharUnits::One() && - getSizeInBits() == UnpackedSize) + getSize() == UnpackedSize) Diag(D->getLocation(), diag::warn_unnecessary_packed) << Context.getTypeDeclType(RD); } @@ -1713,17 +1710,15 @@ ASTContext::getASTRecordLayout(const RecordDecl *D) const { bool IsPODForThePurposeOfLayout = cast(D)->isPOD(); // FIXME: This should be done in FinalizeLayout. - uint64_t DataSize = - IsPODForThePurposeOfLayout ? Builder->Size : Builder->DataSize; - CharUnits NonVirtualSize = - IsPODForThePurposeOfLayout ? - toCharUnitsFromBits(DataSize) : Builder->NonVirtualSize; + CharUnits DataSize = + IsPODForThePurposeOfLayout ? Builder->getSize() : Builder->getDataSize(); + CharUnits NonVirtualSize = + IsPODForThePurposeOfLayout ? DataSize : Builder->NonVirtualSize; - CharUnits RecordSize = toCharUnitsFromBits(Builder->Size); NewEntry = - new (*this) ASTRecordLayout(*this, RecordSize, + new (*this) ASTRecordLayout(*this, Builder->getSize(), Builder->Alignment, - toCharUnitsFromBits(DataSize), + DataSize, Builder->FieldOffsets.data(), Builder->FieldOffsets.size(), NonVirtualSize, @@ -1736,12 +1731,10 @@ ASTContext::getASTRecordLayout(const RecordDecl *D) const { RecordLayoutBuilder Builder(*this, /*EmptySubobjects=*/0); Builder.Layout(D); - CharUnits RecordSize = toCharUnitsFromBits(Builder.Size); - NewEntry = - new (*this) ASTRecordLayout(*this, RecordSize, + new (*this) ASTRecordLayout(*this, Builder.getSize(), Builder.Alignment, - toCharUnitsFromBits(Builder.Size), + Builder.getSize(), Builder.FieldOffsets.data(), Builder.FieldOffsets.size()); } @@ -1797,12 +1790,10 @@ ASTContext::getObjCLayout(const ObjCInterfaceDecl *D, RecordLayoutBuilder Builder(*this, /*EmptySubobjects=*/0); Builder.Layout(D); - CharUnits RecordSize = toCharUnitsFromBits(Builder.Size); - const ASTRecordLayout *NewEntry = - new (*this) ASTRecordLayout(*this, RecordSize, + new (*this) ASTRecordLayout(*this, Builder.getSize(), Builder.Alignment, - toCharUnitsFromBits(Builder.DataSize), + Builder.getDataSize(), Builder.FieldOffsets.data(), Builder.FieldOffsets.size()); diff --git a/test/CodeGen/union.c b/test/CodeGen/union.c index 1883ca639b..5c89e2d72a 100644 --- a/test/CodeGen/union.c +++ b/test/CodeGen/union.c @@ -42,3 +42,5 @@ int RRF(void) {return RRU.a;} // PR6164 typedef union T0 { unsigned int : 0; } T0; T0 t0; + +union { int large_bitfield: 31; char c } u2; -- 2.40.0