[lld] [lld][ELF] Add basic TLSDESC support for LoongArch (PR #94451)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,134 @@
+# REQUIRES: loongarch
+# RUN: rm -rf %t && split-file %s %t && cd %t
+# RUN: llvm-mc -filetype=obj -triple=loongarch64 a.s -o a.64.o
+# RUN: llvm-mc -filetype=obj -triple=loongarch64 c.s -o c.64.o
+# RUN: ld.lld -shared -soname=c.64.so c.64.o -o c.64.so
+# RUN: llvm-mc -filetype=obj -triple=loongarch32 --defsym ELF32=1 a.s -o a.32.o
+# RUN: llvm-mc -filetype=obj -triple=loongarch32 --defsym ELF32=1 c.s -o c.32.o
+# RUN: ld.lld -shared -soname=c.32.so c.32.o -o c.32.so
+
+# RUN: ld.lld -shared -z now a.64.o c.64.o -o a.64.so
+# RUN: llvm-readobj -r -x .got a.64.so | FileCheck --check-prefix=GD64-RELA %s
+# RUN: llvm-objdump --no-show-raw-insn -h -d a.64.so | FileCheck %s --check-prefix=GD64
+
+# RUN: ld.lld -shared -z now a.64.o c.64.o -o rel.64.so -z rel
+# RUN: llvm-readobj -r -x .got rel.64.so | FileCheck --check-prefix=GD64-REL %s
+
+## FIXME: The transition frome TLSDESC to IE/LE has not yet been implemented.
+## Keep the dynamic relocations and hand them over to dynamic linker.
+
+# RUN: ld.lld -e 0 -z now a.64.o c.64.o -o a.64.le
+# RUN: llvm-readobj -r -x .got a.64.le | FileCheck --check-prefix=LE64-RELA %s
+
+# RUN: ld.lld -e 0 -z now a.64.o c.64.so -o a.64.ie
+# RUN: llvm-readobj -r -x .got a.64.ie | FileCheck --check-prefix=IE64-RELA %s
+
+## 32-bit code is mostly the same. We only test a few variants.
+
+# RUN: ld.lld -shared -z now a.32.o c.32.o -o rel.32.so -z rel
+# RUN: llvm-readobj -r -x .got rel.32.so | FileCheck --check-prefix=GD32-REL %s
+
+# GD64-RELA:      .rela.dyn {
+# GD64-RELA-NEXT:   0x20400 R_LARCH_TLS_DESC64 - 0x7FF
+# GD64-RELA-NEXT:   0x203E0 R_LARCH_TLS_DESC64 a 0x0
+# GD64-RELA-NEXT:   0x203F0 R_LARCH_TLS_DESC64 c 0x0
+# GD64-RELA-NEXT: }
+# GD64-RELA:      Hex dump of section '.got':
+# GD64-RELA-NEXT: 0x000203e0 00000000 00000000 00000000 00000000 .
+# GD64-RELA-NEXT: 0x000203f0 00000000 00000000 00000000 00000000 .
+# GD64-RELA-NEXT: 0x00020400 00000000 00000000 00000000 00000000 .
+
+# GD64-REL:      .rel.dyn {
+# GD64-REL-NEXT:   0x203E8 R_LARCH_TLS_DESC64 -
+# GD64-REL-NEXT:   0x203C8 R_LARCH_TLS_DESC64 a
+# GD64-REL-NEXT:   0x203D8 R_LARCH_TLS_DESC64 c
+# GD64-REL-NEXT: }
+# GD64-REL:      Hex dump of section '.got':
+# GD64-REL-NEXT: 0x000203c8 00000000 00000000 00000000 00000000 .
+# GD64-REL-NEXT: 0x000203d8 00000000 00000000 00000000 00000000 .
+# GD64-REL-NEXT: 0x000203e8 00000000 00000000 ff070000 00000000 .
+
+# GD64:      .got     00000030 00000000000203e0
+
+## &.got[a]-. = 0x203e0 - 0x102e0: 0x10 pages, page offset 0x3e0
+# GD64:        102e0: pcalau12i $a0, 16
+# GD64-NEXT:          addi.d $a0, $a0, 992
+# GD64-NEXT:          ld.d $ra, $a0, 0
+# GD64-NEXT:          jirl $ra, $ra, 0
+# GD64-NEXT:          add.d $a1, $a0, $tp
+
+## &.got[b]-. = 0x203e0+32 - 0x102f4: 0x10 pages, page offset 0x400
+# GD64:        102f4: pcalau12i $a0, 16
+# GD64-NEXT:          addi.d $a0, $a0, 1024
+# GD64-NEXT:          ld.d $ra, $a0, 0
+# GD64-NEXT:          jirl $ra, $ra, 0
+# GD64-NEXT:          add.d $a2, $a0, $tp
+
+## &.got[c]-. = 0x23e0+16 - 0x10308: 0x10 pages, page offset 0x3f0
+# GD64:        10308: pcalau12i $a0, 16
+# GD64-NEXT:          addi.d $a0, $a0, 1008
+# GD64-NEXT:          ld.d $ra, $a0, 0
+# GD64-NEXT:          jirl $ra, $ra, 0
+# GD64-NEXT:          add.d $a3, $a0, $tp
+
+# LE64-RELA:      .rela.dyn {
+# LE64-RELA-NEXT:   0x30250 R_LARCH_TLS_DESC64 - 0x8
+# LE64-RELA-NEXT:   0x30260 R_LARCH_TLS_DESC64 - 0x800
+# LE64-RELA-NEXT:   0x30270 R_LARCH_TLS_DESC64 - 0x7FF
+# LE64-RELA-NEXT: }
+# LE64-RELA:      Hex dump of section '.got':
+# LE64-RELA-NEXT: 0x00030250 00000000 00000000 00000000 00000000 .
+# LE64-RELA-NEXT: 0x00030260 00000000 00000000 00000000 00000000 .
+# LE64-RELA-NEXT: 0x00030270 00000000 00000000 00000000 00000000 .
+
+# IE64-RELA:      .rela.dyn {
+# IE64-RELA-NEXT:   0x303D8 R_LARCH_TLS_DESC64 - 0x8
+# IE64-RELA-NEXT:   0x303F8 R_LARCH_TLS_DESC64 - 0x7FF
+# IE64-RELA-NEXT:   0x303E8 R_LARCH_TLS_DESC64 c 0x0
+# IE64-RELA-NEXT: }
+# IE64-RELA:      Hex dump of section '.got':
+# IE64-RELA-NEXT: 0x000303d8 00000000 00000000 00000000 00000000 .
+# IE64-RELA-NEXT: 0x000303e8 00000000 00000000 00000000 00000000 .
+# IE64-RELA-NEXT: 0x000303f8 00000000 00000000 00000000 00000000 .
+
+# GD32-REL:      .rel.dyn {
+# GD32-REL-NEXT:    0x20270 R_LARCH_TLS_DESC32 -
+# GD32-REL-NEXT:    0x20260 R_LARCH_TLS_DESC32 a
+# GD32-REL-NEXT:    0x20268 R_LARCH_TLS_DESC32 c
+# GD32-REL-NEXT: }
+# GD32-REL:      Hex dump of section '.got':
+# GD32-REL-NEXT: 0x00020260 00000000 00000000 00000000 00000000 .
+# GD32-REL-NEXT: 0x00020270 00000000 ff070000                   .
+
+#--- a.s
+.macro add dst, src1, src2
+.ifdef ELF32
+add.w \dst, \src1, \src2
+.else
+add.d \dst, \src1, \src2
+.endif
+.endm
+
+la.tls.desc $a0, a
+add $a1, $a0, $tp
+
+la.tls.desc $a0, b
+add $a2, $a0, $tp
+
+la.tls.desc $a0, c
+add $a3, $a0, $tp
+
+#.section .tbss
+.section .tbss,"awT", at nobits
+.globl a
+.zero 8
+a:
+.zero 2039  ## Place b at 0x7ff
+b:
+.zero 1
+
+#--- c.s
+.section .tbss,"awT", at nobits
+#.tbss
----------------
MaskRay wrote:

delete `.tbss`

https://github.com/llvm/llvm-project/pull/94451