From 6e8575b88bfb2634d7b28c0c4d5ed2a6acc8418a Mon Sep 17 00:00:00 2001 From: Daniel Dunbar Date: Mon, 4 May 2009 23:23:09 +0000 Subject: [PATCH] Fix the field count in interface record layout (it was incorrectly compensating for super classes). This was making the reported class sizes for empty classes very, very wrong. - Also, we now report the size info for an empty class like gcc (as the offset of the start, not as 0, 0). - Add a few more test cases we were mishandling before (padding bit field at end of struct, for example). git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70938 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/AST/ASTContext.cpp | 6 --- lib/CodeGen/CGObjCMac.cpp | 13 +++--- test/CodeGenObjC/interface-layout-64.m | 55 +++++++++++++++++++++++--- 3 files changed, 57 insertions(+), 17 deletions(-) diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp index a9f13c9518..a947fea95a 100644 --- a/lib/AST/ASTContext.cpp +++ b/lib/AST/ASTContext.cpp @@ -713,10 +713,6 @@ ASTContext::getObjCLayout(const ObjCInterfaceDecl *D, ASTRecordLayout *NewEntry = NULL; if (ObjCInterfaceDecl *SD = D->getSuperClass()) { - // FIXME: This increment of FieldCount is wrong, we don't actually - // count the super class as a member (see the field index passed - // to LayoutField below). - FieldCount++; const ASTRecordLayout &SL = getASTObjCInterfaceLayout(SD); unsigned Alignment = SL.getAlignment(); uint64_t Size = SL.getSize(); @@ -729,8 +725,6 @@ ASTContext::getObjCLayout(const ObjCInterfaceDecl *D, ObjCLayouts[Key] = NewEntry = new ASTRecordLayout(Size, Alignment); NewEntry->InitializeLayout(FieldCount); - // Super class is at the beginning of the layout. - NewEntry->SetFieldOffset(0, 0); } else { ObjCLayouts[Key] = NewEntry = new ASTRecordLayout(); NewEntry->InitializeLayout(FieldCount); diff --git a/lib/CodeGen/CGObjCMac.cpp b/lib/CodeGen/CGObjCMac.cpp index 1a1ef83123..1f58389ab8 100644 --- a/lib/CodeGen/CGObjCMac.cpp +++ b/lib/CodeGen/CGObjCMac.cpp @@ -4222,13 +4222,14 @@ void CGObjCNonFragileABIMac::GetClassSizeInfo(const ObjCImplementationDecl *OID, const ASTRecordLayout &RL = CGM.getContext().getASTObjCImplementationLayout(OID); - if (!RL.getFieldCount()) { - InstanceStart = InstanceSize = 0; - return; - } - - InstanceStart = RL.getFieldOffset(0) / 8; + // InstanceSize is really instance end. InstanceSize = llvm::RoundUpToAlignment(RL.getNextOffset(), 8) / 8; + + // If there are no fields, the start is the same as the end. + if (!RL.getFieldCount()) + InstanceStart = InstanceSize; + else + InstanceStart = RL.getFieldOffset(0) / 8; } void CGObjCNonFragileABIMac::GenerateClass(const ObjCImplementationDecl *ID) { diff --git a/test/CodeGenObjC/interface-layout-64.m b/test/CodeGenObjC/interface-layout-64.m index ee01ac6bb6..db860e8518 100644 --- a/test/CodeGenObjC/interface-layout-64.m +++ b/test/CodeGenObjC/interface-layout-64.m @@ -1,17 +1,36 @@ -// RUN: clang-cc -triple x86_64-apple-darwin9 -emit-llvm -o %t %s && +// RUN: clang-cc -fobjc-tight-layout -triple x86_64-apple-darwin9 -emit-llvm -o %t %s && // RUNX: llvm-gcc -m64 -emit-llvm -S -o %t %s && // RUN: grep '@"OBJC_IVAR_$_I3._iv2" = global i64 8, section "__DATA, __objc_const", align 8' %t && // RUN: grep '@"OBJC_IVAR_$_I3._iv3" = global i64 12, section "__DATA, __objc_const", align 8' %t && -// RUN: grep '@"OBJC_IVAR_$_I4._iv4" = global i64 16, section "__DATA, __objc_const", align 8' %t && -// RUN: grep '@"OBJC_IVAR_$_I5._iv5" = global i64 24, section "__DATA, __objc_const", align 8' %t && -// RUN: grep '@"OBJC_IVAR_$_I5._iv6_synth" = global i64 28, section "__DATA, __objc_const", align 8' %t && -// RUN: grep '@"OBJC_IVAR_$_I5._iv7_synth" = global i64 32, section "__DATA, __objc_const", align 8' %t && +// RUN: grep '@"OBJC_IVAR_$_I4._iv4" = global i64 13, section "__DATA, __objc_const", align 8' %t && +// RUN: grep '@"OBJC_IVAR_$_I5._iv5" = global i64 14, section "__DATA, __objc_const", align 8' %t && +// RUN: grep '@"OBJC_IVAR_$_I5._iv6_synth" = global i64 16, section "__DATA, __objc_const", align 8' %t && +// RUN: grep '@"OBJC_IVAR_$_I5._iv7_synth" = global i64 20, section "__DATA, __objc_const", align 8' %t && +// RUN: grep '@"OBJC_IVAR_$_I6.iv0" = global i64 0, section "__DATA, __objc_const", align 8' %t && +// RUN: grep '@"OBJC_IVAR_$_I8.b" = global i64 8, section "__DATA, __objc_const", align 8' %t && +// RUN: grep '@"OBJC_IVAR_$_I9.iv0" = global i64 0, section "__DATA, __objc_const", align 8' %t && +// RUN: grep '@"OBJC_IVAR_$_I10.iv1" = global i64 4, section "__DATA, __objc_const", align 8' %t && +// RUN: grep '@"OBJC_IVAR_$_I12.iv2" = global i64 8, section "__DATA, __objc_const", align 8' %t && +// RUN: grep '_OBJC_CLASS_RO_$_I3" = internal global .* { i32 0, i32 8, i32 13, .*' %t && +// RUN: grep '_OBJC_CLASS_RO_$_I4" = internal global .* { i32 0, i32 13, i32 14, .*' %t && +// RUN: grep '_OBJC_CLASS_RO_$_I5" = internal global .* { i32 0, i32 14, i32 24, .*' %t && // RUN: grep '_OBJC_CLASS_RO_$_I6" = internal global .* { i32 2, i32 0, i32 1, .*' %t && // RUN: grep '_OBJC_CLASS_RO_$_I8" = internal global .* { i32 0, i32 8, i32 16, .*' %t && +// RUN: grep '_OBJC_CLASS_RO_$_I9" = internal global .* { i32 2, i32 0, i32 4, .*' %t && +// RUN: grep '_OBJC_CLASS_RO_$_I10" = internal global .* { i32 0, i32 4, i32 5, .*' %t && +// RUN: grep '_OBJC_CLASS_RO_$_I11" = internal global .* { i32 0, i32 5, i32 5, .*' %t && +// RUN: grep '_OBJC_CLASS_RO_$_I12" = internal global .* { i32 0, i32 8, i32 12, .*' %t && // RUN: true +/* + Compare to: + gcc -m64 -S -o - interface-layout-64.m | grep '^_OBJC_IVAR_$_*.*' -A 1 + and + gcc -m64 -S -o - interface-layout-64.m | grep '^l.*_CLASS_RO_$_I[0-9]*' -A 3 + */ + struct s0 { double x; }; @@ -77,3 +96,29 @@ struct s0 { @implementation I8 @end +// Padding bit-fields +@interface I9 { + unsigned iv0 : 2; + unsigned : 0; +} +@end +@implementation I9 +@end +@interface I10 : I9 { + unsigned iv1 : 2; +} +@end +@implementation I10 +@end + +// Empty structures +@interface I11 : I10 +@end +@implementation I11 +@end +@interface I12 : I11 { + unsigned iv2; +} +@end +@implementation I12 +@end -- 2.40.0