[lld] [lld] Add target support for SystemZ (s390x) (PR #75643)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,142 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o
+# RUN: echo '.tbss; .globl b, c; b: .zero 4; c:' | llvm-mc -filetype=obj -triple=s390x-unknown-linux - -o %t1.o
+# RUN: ld.lld -shared -soname=t1.so %t1.o -o %t1.so
+
+# RUN: ld.lld -shared %t.o %t1.o -o %t.so
+# RUN: llvm-readelf -r %t.so | FileCheck --check-prefix=GD-REL %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t.so | FileCheck --check-prefix=GD %s
+# RUN: llvm-objdump --section .data.rel.ro --full-contents %t.so | FileCheck --check-prefix=GD-DATA %s
+
+# RUN: ld.lld %t.o %t1.o -o %t
+# RUN: llvm-readelf -r %t | FileCheck --check-prefix=NOREL %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t | FileCheck --check-prefix=LE %s
+# RUN: llvm-objdump --section .data.rel.ro --full-contents %t | FileCheck --check-prefix=LE-DATA %s
+
+# RUN: ld.lld %t.o %t1.so -o %t
+# RUN: llvm-readelf -r %t | FileCheck --check-prefix=IE-REL %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t | FileCheck --check-prefix=IE %s
+# RUN: llvm-objdump --section .data.rel.ro --full-contents %t | FileCheck --check-prefix=IE-DATA %s
+
+# GD-REL: Relocation section '.rela.dyn' at offset {{.*}} contains 6 entries:
+# GD-REL: 0000000000002570 0000000200000036 R_390_TLS_DTPMOD 0000000000000008 a + 0
+# GD-REL: 0000000000002578 0000000200000037 R_390_TLS_DTPOFF 0000000000000008 a + 0
+# GD-REL: 0000000000002580 0000000300000036 R_390_TLS_DTPMOD 000000000000000c b + 0
+# GD-REL: 0000000000002588 0000000300000037 R_390_TLS_DTPOFF 000000000000000c b + 0
+# GD-REL: 0000000000002590 0000000400000036 R_390_TLS_DTPMOD 0000000000000010 c + 0
+# GD-REL: 0000000000002598 0000000400000037 R_390_TLS_DTPOFF 0000000000000010 c + 0
+
+## _GLOBAL_OFFSET_TABLE is at 0x2558
+# GD:      larl    %r12, 0x2558
+
+## GOT offset of the TLS descriptor for a is at 0x2460
+# GD-NEXT: lgrl    %r2, 0x2460
+# GD-NEXT: brasl   %r14, 0x1440
+# GD-NEXT: lgf     %r2, 0(%r2,%r7)
+
+## GOT offset of the TLS descriptor for b is at 0x2468
+# GD-NEXT: lgrl    %r2, 0x2468
+# GD-NEXT: brasl   %r14, 0x1440
+# GD-NEXT: lgf     %r2, 0(%r2,%r7)
+
+## GOT offset of the TLS descriptor for c is at 0x2470
+# GD-NEXT: lgrl    %r2, 0x2470
+# GD-NEXT: brasl   %r14, 0x1440
+# GD-NEXT: lgf     %r2, 0(%r2,%r7)
+
+## TLS descriptor addresses / GOT offsets:
----------------
MaskRay wrote:

term misuse? s390x doesn't have TLSDESC

https://github.com/llvm/llvm-project/pull/75643