[llvm] [LoongArch] Support R_LARCH_{ADD, SUB}_ULEB128 for .uleb128 and force relocs when sym is not in section (PR #76433)

[Lu Weining via llvm-commits]

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@@ -8,12 +8,23 @@
 # NORELAX-NEXT:      0x10 R_LARCH_PCALA_HI20 .text 0x0
 # NORELAX-NEXT:      0x14 R_LARCH_PCALA_LO12 .text 0x0
 # NORELAX-NEXT:    }
+# NORELAX-NEXT:    Section ({{.*}}) .rela.data {
+# NORELAX-NEXT:      0x30 R_LARCH_ADD8 foo 0x0
+# NORELAX-NEXT:      0x30 R_LARCH_SUB8 .text 0x10
+# NORELAX-NEXT:      0x31 R_LARCH_ADD16 foo 0x0
+# NORELAX-NEXT:      0x31 R_LARCH_SUB16 .text 0x10
+# NORELAX-NEXT:      0x33 R_LARCH_ADD32 foo 0x0
+# NORELAX-NEXT:      0x33 R_LARCH_SUB32 .text 0x10
+# NORELAX-NEXT:      0x37 R_LARCH_ADD64 foo 0x0
+# NORELAX-NEXT:      0x37 R_LARCH_SUB64 .text 0x10
+# NORELAX-NEXT:    }
 # NORELAX-NEXT:  ]
 
 # NORELAX:      Hex dump of section '.data':
-# NORELAX-NEXT: 0x00000000 04040004 00000004 00000000 0000000c
-# NORELAX-NEXT: 0x00000010 0c000c00 00000c00 00000000 00000808
-# NORELAX-NEXT: 0x00000020 00080000 00080000 00000000 00
+# NORELAX-NEXT: 0x00000000 04040004 00000004 00000000 00000004
+# NORELAX-NEXT: 0x00000010 0c0c000c 0000000c 00000000 00000000
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SixWeining wrote:

Should the thirty-first byte be `0c`?

https://github.com/llvm/llvm-project/pull/76433