[lld] [lld][LoongArch] Support the R_LARCH_CALL36 relocation type (PR #73346)

[Lu Weining via llvm-commits]

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@@ -0,0 +1,41 @@
+# REQUIRES: loongarch
+# RUN: rm -rf %t && split-file %s %t
+# RUN: llvm-mc --filetype=obj --triple=loongarch64-unknown-elf %t/a.s -o %t/a.o
+# RUN: ld.lld %t/a.o -shared -T %t/a.t -o %t/a.so
+# RUN: llvm-readelf -x .got.plt %t/a.so | FileCheck --check-prefix=GOTPLT %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t/a.so | FileCheck %s
+
+## PLT should be present in this case.
+# CHECK:       Disassembly of section .plt:
+# CHECK:       <.plt>:
+##             bar at plt:
+# CHECK:       1234520:  pcaddu12i $t3, 64{{$}}
+# CHECK-NEXT:            ld.d $t3, $t3, 536{{$}}
+# CHECK-NEXT:            jirl $t1, $t3, 0
+# CHECK-NEXT:            nop
+
+# CHECK:      Disassembly of section .text:
+# CHECK:      <foo>:
+## hi20 = bar at plt - pc + (1 << 17) >> 18 = 0x1234520 - 0x1274670 + 0x20000 >> 18 = -1
+## lo18 = bar at plt - pc & (1 << 18) - 1 = 0x1234520 - 0x1274670 & 0x3ffff = -336
+# CHECK-NEXT: pcaddu18i $t0, -1{{$}}
+# CHECK-NEXT: jirl $zero, $t0, -336{{$}}
+
+# GOTPLT:      section '.got.plt':
+# GOTPLT-NEXT: 0x01274728 00000000 00000000 00000000 00000000
+# GOTPLT-NEXT: 0x01274738 00452301 00000000
+
+#--- a.t
+SECTIONS {
+ .plt   0x1234500: { *(.plt) }
+ .text  0x1274670: { *(.text) }
+}
+
+#--- a.s
+.text
+.global foo
+.global bar
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SixWeining wrote:

But seems llvm-mc will not generate the symbol `bar` in the output object file if I remove this line.

https://github.com/llvm/llvm-project/pull/73346