[MIPS][COFF] Missing support for thread local variables

[hpoussin]

Using clang version 20.1.2

llc -mtriple=mipsel-w64-windows-gnu test.ll --filetype=obj

@foo = thread_local global i32 0

define ptr @bar() {
  %1 = call ptr @llvm.threadlocal.address.p0(ptr @foo)
  ret ptr %1
}

gives

<unknown>:0: error: unsupported relocation type
<unknown>:0: error: unsupported relocation type

[llvmbot]

@llvm/issue-subscribers-backend-mips

Author: Hervé Poussineau (hpoussin)

Using clang version 20.1.2

llc -mtriple=mipsel-w64-windows-gnu test.ll --filetype=obj

@<!-- -->foo = thread_local global i32 0

define ptr @<!-- -->bar() {
  %1 = call ptr @<!-- -->llvm.threadlocal.address.p0(ptr @<!-- -->foo)
  ret ptr %1
}

gives

<unknown>:0: error: unsupported relocation type
<unknown>:0: error: unsupported relocation type

[brad0]

cc @yingopq @wzssyqa