Remember the maximum alignment used to refer to a common symbol.
llvm-svn: 246517
diff --git a/lld/ELF/Symbols.cpp b/lld/ELF/Symbols.cpp
index 7eb7dda..f2b484d 100644
--- a/lld/ELF/Symbols.cpp
+++ b/lld/ELF/Symbols.cpp
@@ -33,10 +33,15 @@
if (L.first && L.second) {
if (isCommon()) {
if (Other->isCommon()) {
- // FIXME: We also need to remember the alignment restriction.
- if (cast<DefinedCommon<ELFT>>(this)->Sym.st_size >=
- cast<DefinedCommon<ELFT>>(Other)->Sym.st_size)
+ auto *ThisC = cast<DefinedCommon<ELFT>>(this);
+ auto *OtherC = cast<DefinedCommon<ELFT>>(Other);
+ typename DefinedCommon<ELFT>::uintX_t MaxAlign =
+ std::max(ThisC->MaxAlignment, OtherC->MaxAlignment);
+ if (ThisC->Sym.st_size >= OtherC->Sym.st_size) {
+ ThisC->MaxAlignment = MaxAlign;
return 1;
+ }
+ OtherC->MaxAlignment = MaxAlign;
return -1;
}
return -1;
diff --git a/lld/ELF/Symbols.h b/lld/ELF/Symbols.h
index ba6be5c..7f7578d 100644
--- a/lld/ELF/Symbols.h
+++ b/lld/ELF/Symbols.h
@@ -141,7 +141,9 @@
typedef typename std::conditional<ELFT::Is64Bits, uint64_t, uint32_t>::type
uintX_t;
explicit DefinedCommon(StringRef N, const Elf_Sym &Sym)
- : Defined<ELFT>(Base::DefinedCommonKind, N, Sym) {}
+ : Defined<ELFT>(Base::DefinedCommonKind, N, Sym) {
+ MaxAlignment = Sym.st_value;
+ }
static bool classof(const SymbolBody *S) {
return S->kind() == Base::DefinedCommonKind;
@@ -150,6 +152,9 @@
// The output offset of this common symbol in the output bss. Computed by the
// writer.
uintX_t OffsetInBSS;
+
+ // The maximum alignment we have seen for this symbol.
+ uintX_t MaxAlignment;
};
// Regular defined symbols read from object file symbol tables.
diff --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp
index 1ac20b4..ed1ae93 100644
--- a/lld/ELF/Writer.cpp
+++ b/lld/ELF/Writer.cpp
@@ -411,7 +411,7 @@
template <class ELFT>
static bool cmpAlign(const DefinedCommon<ELFT> *A,
const DefinedCommon<ELFT> *B) {
- return A->Sym.st_value > B->Sym.st_value;
+ return A->MaxAlignment > B->MaxAlignment;
}
// Create output section objects and add them to OutputSections.
@@ -457,7 +457,7 @@
uintX_t Off = BSSSec->getSize();
for (DefinedCommon<ELFT> *C : CommonSymbols) {
const Elf_Sym &Sym = C->Sym;
- uintX_t Align = Sym.st_value;
+ uintX_t Align = C->MaxAlignment;
Off = RoundUpToAlignment(Off, Align);
C->OffsetInBSS = Off;
Off += Sym.st_size;
diff --git a/lld/test/elf2/Inputs/common.s b/lld/test/elf2/Inputs/common.s
index fd5a99e..ea8ba91 100644
--- a/lld/test/elf2/Inputs/common.s
+++ b/lld/test/elf2/Inputs/common.s
@@ -1,2 +1,3 @@
.comm sym1,8,4
.comm sym2,4,4
+.comm sym4,4,16
diff --git a/lld/test/elf2/common.s b/lld/test/elf2/common.s
index 535411f..1e33933 100644
--- a/lld/test/elf2/common.s
+++ b/lld/test/elf2/common.s
@@ -12,11 +12,19 @@
// CHECK-NEXT: ]
// CHECK-NEXT: Address: 0x1000
// CHECK-NEXT: Offset:
-// CHECK-NEXT: Size: 18
+// CHECK-NEXT: Size: 22
+// CHECK: Name: sym4
+// CHECK-NEXT: Value: 0x1000
+// CHECK-NEXT: Size: 4
+// CHECK-NEXT: Binding: Global
+// CHECK-NEXT: Type: Object
+// CHECK-NEXT: Other: 0
+// CHECK-NEXT: Section: .bss
+
// CHECK: Name: sym3
-// CHECK-NEXT: Value: 0x1010
+// CHECK-NEXT: Value: 0x1014
// CHECK-NEXT: Size: 2
// CHECK-NEXT: Binding: Global
// CHECK-NEXT: Type: Object
@@ -24,7 +32,7 @@
// CHECK-NEXT: Section: .bss
// CHECK: Name: sym2
-// CHECK-NEXT: Value: 0x1008
+// CHECK-NEXT: Value: 0x100C
// CHECK-NEXT: Size: 8
// CHECK-NEXT: Binding: Global
// CHECK-NEXT: Type: Object
@@ -32,7 +40,7 @@
// CHECK-NEXT: Section: .bss
// CHECK: Name: sym1
-// CHECK-NEXT: Value: 0x1000
+// CHECK-NEXT: Value: 0x1004
// CHECK-NEXT: Size: 8
// CHECK-NEXT: Binding: Global
// CHECK-NEXT: Type: Object
@@ -46,3 +54,4 @@
.comm sym1,4,4
.comm sym2,8,4
.comm sym3,2,2
+.comm sym4,4,2