1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2025-01-31 12:41:49 +01:00
llvm-mirror/test/CodeGen/X86/elf-associated-discarded.ll
Fangrui Song 6fcac4f990 [MC] Set sh_link to 0 if the associated symbol is undefined
Part of https://bugs.llvm.org/show_bug.cgi?id=41734

LTO can drop externally available definitions. Such AssociatedSymbol is
not associated with a symbol. ELFWriter::writeSection() will assert.

Allow a SHF_LINK_ORDER section to have sh_link=0.

We need to give sh_link a syntax, a literal zero in the linked-to symbol
position, e.g. `.section name,"ao",@progbits,0`

Reviewed By: pcc

Differential Revision: https://reviews.llvm.org/D72899
2020-08-03 13:43:48 -07:00

24 lines
848 B
LLVM

;; Test that we keep SHF_LINK_ORDER but reset sh_link to 0 if the associated
;; symbol is not defined.
; RUN: llc -mtriple=x86_64 -data-sections=1 < %s | FileCheck %s
; RUN: llc -filetype=obj -mtriple=x86_64 -data-sections=1 < %s | llvm-readelf -S - | FileCheck --check-prefix=SEC %s
;; FIXME The assembly output cannot be assembled because foo is not defined.
;; This is difficult to fix because we allow loops (see elf-associated.ll
;; .data.c and .data.d).
; CHECK: .section .data.a,"awo",@progbits,foo
; CHECK: .section .data.b,"awo",@progbits,foo
;; No 'L' (SHF_LINK_ORDER). sh_link=0.
; SEC; Name {{.*}} Flg Lk Inf
; SEC: .data.a {{.*}} WAL 0 0
; SEC: .data.b {{.*}} WAL 0 0
;; The definition may be discarded by LTO.
declare void @foo()
@a = global i32 1, !associated !0
@b = global i32 1, !associated !0
!0 = !{void ()* @foo}