argument. Instead, use a pair of .local and .comm directives.
This avoids spurious differences between binaries built by the
integrated assembler vs. those built by the external assembler,
since the external assembler may impose alignment requirements
on .lcomm symbols where the integrated assembler does not.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168704
91177308-0d34-0410-b5e6-
96231b3b80d8
- if (Align == 1 ||
- MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
+ // Use .lcomm only if it supports user-specified alignment.
+ // Otherwise, while it would still be correct to use .lcomm in some
+ // cases (e.g. when Align == 1), the external assembler might enfore
+ // some -unknown- default alignment behavior, which could cause
+ // spurious differences between external and integrated assembler.
+ // Prefer to simply fall back to .local / .comm in this case.
+ if (MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
// .lcomm _foo, 42
OutStreamer.EmitLocalCommonSymbol(GVSym, Size, Align);
return;
// .lcomm _foo, 42
OutStreamer.EmitLocalCommonSymbol(GVSym, Size, Align);
return;
@STRIDE = internal global i32 8
; ASM: .type array00,%object @ @array00
@STRIDE = internal global i32 8
; ASM: .type array00,%object @ @array00
-; ASM-NEXT: .lcomm array00,80
+; ASM-NEXT: .local array00
+; ASM-NEXT: .comm array00,80,1
; ASM-NEXT: .type _MergedGlobals,%object @ @_MergedGlobals
; ASM-NEXT: .type _MergedGlobals,%object @ @_MergedGlobals
@c = internal global i8 0, align 1
@x = internal global i32 0, align 4
@c = internal global i8 0, align 1
@x = internal global i32 0, align 4
-; CHECK: .lcomm c,1
-; .lcomm doesn't support alignment.
+; .lcomm doesn't support alignment, so we always use .local/.comm.
+; CHECK: .local c
+; CHECK-NEXT: .comm c,1,1
; CHECK: .local x
; CHECK-NEXT: .comm x,4,4
; CHECK: .local x
; CHECK-NEXT: .comm x,4,4