[lld] [ELF] Support R_RISCV_SET_ULEB128/R_RISCV_SUB_ULEB128 in non-SHF_ALLOC sections (PR #72610)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,129 @@
+# REQUIRES: riscv
+# RUN: rm -rf %t && split-file %s %t && cd %t
+# RUN: llvm-mc -filetype=obj -triple=riscv64 -mattr=+relax a.s -o a.o
+# RUN: llvm-readobj -r -x .debug_rnglists -x .debug_loclists a.o | FileCheck %s --check-prefix=REL
+# RUN: ld.lld -shared --gc-sections a.o -o a.so
+# RUN: llvm-readelf -x .debug_rnglists -x .debug_loclists a.so | FileCheck %s
+
+# REL:      .rela.debug_rnglists {
+# REL-NEXT:   0x0 R_RISCV_SET_ULEB128 w1 0x83
+# REL-NEXT:   0x0 R_RISCV_SUB_ULEB128 w2 0x0
+# REL-NEXT:   0x1 R_RISCV_SET_ULEB128 w2 0x78
+# REL-NEXT:   0x1 R_RISCV_SUB_ULEB128 w1 0x0
+# REL-NEXT:   0x3 R_RISCV_SET_ULEB128 w1 0x89
+# REL-NEXT:   0x3 R_RISCV_SUB_ULEB128 w2 0x0
+# REL-NEXT:   0x5 R_RISCV_SET_ULEB128 w2 0x3FF8
+# REL-NEXT:   0x5 R_RISCV_SUB_ULEB128 w1 0x0
+# REL-NEXT:   0x8 R_RISCV_SET_ULEB128 w1 0x4009
+# REL-NEXT:   0x8 R_RISCV_SUB_ULEB128 w2 0x0
+# REL-NEXT:   0xB R_RISCV_SET_ULEB128 w2 0x1FFFF8
+# REL-NEXT:   0xB R_RISCV_SUB_ULEB128 w1 0x0
+# REL-NEXT:   0xF R_RISCV_SET_ULEB128 w1 0x200009
+# REL-NEXT:   0xF R_RISCV_SUB_ULEB128 w2 0x0
+# REL-NEXT: }
+# REL:      .rela.debug_loclists {
+# REL-NEXT:   0x0 R_RISCV_SET_ULEB128 w2 0x3
+# REL-NEXT:   0x0 R_RISCV_SUB_ULEB128 w1 0x4
+# REL-NEXT:   0x1 R_RISCV_SET_ULEB128 x2 0x0
+# REL-NEXT:   0x1 R_RISCV_SUB_ULEB128 x1 0x0
+# REL-NEXT: }
+
+# REL:        Hex dump of section '.debug_rnglists':
+# REL-NEXT:   0x00000000 7b800181 01808001 81800180 80800181 {
+# REL-NEXT:   0x00000010 808001                              .
+# REL:        Hex dump of section '.debug_loclists':
+# REL-NEXT:   0x00000000 0008                                  .
+
+# CHECK:      Hex dump of section '.debug_rnglists':
+# CHECK-NEXT: 0x00000000 7ffc0085 01fcff00 858001fc ffff0085 .
+# CHECK-NEXT: 0x00000010 808001                              .
+# CHECK:      Hex dump of section '.debug_loclists':
+# CHECK-NEXT: 0x00000000 0300                                .
+
+# RUN: ld.lld -shared --gc-sections -z dead-reloc-in-nonalloc=.debug_loclists=0x7f a.o -o a127.so
+# RUN: llvm-readelf -x .debug_loclists a127.so | FileCheck %s --check-prefix=CHECK127
+# CHECK127:      Hex dump of section '.debug_loclists':
+# CHECK127-NEXT: 0x00000000 037f                                .
+
+# RUN: not ld.lld -shared --gc-sections -z dead-reloc-in-nonalloc=.debug_loclists=0x80 a.o 2>&1 | FileCheck %s --check-prefix=CHECK128
+# CHECK128: error: a.o:(.debug_loclists+0x1): ULEB128 value 128 exceeds available space; references 'x2'
+
+# RUN: llvm-mc -filetype=obj -triple=riscv64 -mattr=+relax sub.s -o sub.o
+# RUN: not ld.lld -shared sub.o 2>&1 | FileCheck %s --check-prefix=SUB
+# SUB: error: sub.o:(.debug_rnglists+0x8): unknown relocation (61) against symbol w2
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MaskRay wrote:

We could, but I feel that the utility of the dedicated diagnostic will be very low. So it is probably not useful to have more code on it...

https://github.com/llvm/llvm-project/pull/72610