File: x86-64-tlsdesc-ld.s

package info (click to toggle)
swiftlang 6.0.3-2
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid, trixie
  • size: 2,519,992 kB
  • sloc: cpp: 9,107,863; ansic: 2,040,022; asm: 1,135,751; python: 296,500; objc: 82,456; f90: 60,502; lisp: 34,951; pascal: 19,946; sh: 18,133; perl: 7,482; ml: 4,937; javascript: 4,117; makefile: 3,840; awk: 3,535; xml: 914; fortran: 619; cs: 573; ruby: 573
file content (53 lines) | stat: -rw-r--r-- 1,703 bytes parent folder | download | duplicates (14)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
# REQUIRES: x86
# RUN: llvm-mc -filetype=obj -triple=x86_64 %s -o %t.o

# RUN: ld.lld -shared %t.o -o %t.so
# RUN: llvm-readobj -r %t.so | FileCheck --check-prefix=LD-REL %s
# RUN: llvm-objdump --no-print-imm-hex -d --no-show-raw-insn %t.so | FileCheck --check-prefix=LD %s

# RUN: ld.lld %t.o -o %t
# RUN: llvm-readelf -r %t | FileCheck --check-prefix=NOREL %s
# RUN: llvm-objdump --no-print-imm-hex -d --no-show-raw-insn %t | FileCheck --check-prefix=LE %s

## Check _TLS_MODULE_BASE_ used by LD produces a dynamic relocation with a value of 0.
# LD-REL:      .rela.dyn {
# LD-REL-NEXT:   0x2318 R_X86_64_TLSDESC - 0x0
# LD-REL-NEXT: }

## 0x2318-0x1267 = 4273
## dtpoff(a) = 8, dtpoff(b) = 12
# LD:            leaq 4273(%rip), %rax
# LD-NEXT: 1267: callq *(%rax)
# LD-NEXT:       movl %fs:8(%rax), %edx
# LD-NEXT:       addl %fs:12(%rax), %edx

## When producing an executable, the LD code sequence can be relaxed to LE.
## It is the same as GD->LE.
## tpoff(_TLS_MODULE_BASE_) = 0, tpoff(a) = -8, tpoff(b) = -4

# NOREL: no relocations

# LE:      movq $0, %rax
# LE-NEXT: nop
# LE-NEXT: movl %fs:-8(%rax), %edx
# LE-NEXT: addl %fs:-4(%rax), %edx

# RUN: ld.lld -r %t.o -o %t.ro
# RUN: llvm-readelf -s %t.ro | FileCheck --check-prefix=RELOCATABLE %s
# RUN: ld.lld %t.ro -o %t
# RUN: llvm-readelf -r %t | FileCheck --check-prefix=NOREL %s
# RUN: llvm-objdump --no-print-imm-hex -d --no-show-raw-insn %t | FileCheck --check-prefix=LE %s

# RELOCATABLE: 0000000000000000 0 TLS GLOBAL DEFAULT UND _TLS_MODULE_BASE_

leaq _TLS_MODULE_BASE_@tlsdesc(%rip), %rax
call *_TLS_MODULE_BASE_@tlscall(%rax)
movl %fs:a@dtpoff(%rax), %edx
addl %fs:b@dtpoff(%rax), %edx

.section .tbss
.zero 8
a:
.zero 4
b:
.zero 4