Index: lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
===================================================================
--- lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
+++ lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
@@ -271,6 +271,10 @@
     assert(Type == RT32_32);
     assert(!IsPCRel);
     return ELF::R_386_GOTOFF;
+  case MCSymbolRefExpr::VK_TLSCALL:
+    return ELF::R_386_TLS_DESC_CALL;
+  case MCSymbolRefExpr::VK_TLSDESC:
+    return ELF::R_386_TLS_GOTDESC;
   case MCSymbolRefExpr::VK_TPOFF:
     assert(Type == RT32_32);
     assert(!IsPCRel);
Index: lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp
===================================================================
--- lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp
+++ lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp
@@ -524,9 +524,23 @@
     // indirect register encoding, this handles addresses like [EAX].  The
     // encoding for [EBP] with no displacement means [disp32] so we handle it
     // by emitting a displacement of 0 below.
-    if (Disp.isImm() && Disp.getImm() == 0 && BaseRegNo != N86::EBP) {
-      EmitByte(ModRMByte(0, RegOpcodeField, BaseRegNo), CurByte, OS);
-      return;
+    if (BaseRegNo != N86::EBP) {
+      if (Disp.isImm() && Disp.getImm() == 0) {
+        EmitByte(ModRMByte(0, RegOpcodeField, BaseRegNo), CurByte, OS);
+        return;
+      }
+
+      // If the displacement is @tlscall, treat it as a zero.
+      if (Disp.isExpr()) {
+        auto *Sym = dyn_cast<MCSymbolRefExpr>(Disp.getExpr());
+        if (Sym && Sym->getKind() == MCSymbolRefExpr::VK_TLSCALL) {
+          // This is exclusively used by call *a@tlscall(base). The relocation
+          // (R_386_TLSCALL or R_X86_64_TLSCALL) applies to the beginning.
+          Fixups.push_back(MCFixup::create(0, Sym, FK_NONE, MI.getLoc()));
+          EmitByte(ModRMByte(0, RegOpcodeField, BaseRegNo), CurByte, OS);
+          return;
+        }
+      }
     }
 
     // Otherwise, if the displacement fits in a byte, encode as [REG+disp8].
Index: test/MC/ELF/relocation-tls.s
===================================================================
--- test/MC/ELF/relocation-tls.s
+++ /dev/null
@@ -1,26 +0,0 @@
-// RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o - | llvm-readobj -S --sr | FileCheck  %s
-
-// Test that we produce the correct relocation.
-
-        leaq    _ZL3ccc@TLSDESC(%rip), %rax
-        call    *_ZL3ccc@TLSCALL(%rax)
-        addq    %fs:0, %rax
-
-// CHECK: Section {
-// CHECK:   Index:
-// CHECK:   Name: .rela.text
-// CHECK-NEXT:   Type: SHT_RELA
-// CHECK-NEXT:   Flags [
-// CHECK-NEXT:   ]
-// CHECK-NEXT:   Address: 0x0
-// CHECK-NEXT:   Offset:
-// CHECK-NEXT:   Size:
-// CHECK-NEXT:   Link:
-// CHECK-NEXT:   Info:
-// CHECK-NEXT:   AddressAlignment: 8
-// CHECK-NEXT:   EntrySize: 24
-// CHECK-NEXT:   Relocations [
-// CHECK-NEXT:     0x3 R_X86_64_GOTPC32_TLSDESC _ZL3ccc 0xFFFFFFFFFFFFFFFC
-// CHECK-NEXT:     0x9 R_X86_64_TLSDESC_CALL _ZL3ccc 0x0
-// CHECK-NEXT:   ]
-// CHECK-NEXT: }
Index: test/MC/X86/tlsdesc-32.s
===================================================================
--- /dev/null
+++ test/MC/X86/tlsdesc-32.s
@@ -0,0 +1,16 @@
+# RUN: llvm-mc -triple i386-pc-linux-musl %s | FileCheck --check-prefix=PRINT %s
+
+# RUN: llvm-mc -filetype=obj -triple i386-pc-linux-musl %s -o %t
+# RUN: llvm-objdump -dr --no-show-raw-insn %t | FileCheck %s
+
+# PRINT:      leal a@tlsdesc(%ebx), %eax
+# PRINT-NEXT: calll *a@tlscall(%eax)
+
+# CHECK:      0: leal (%ebx), %eax
+# CHECK-NEXT:   00000002: R_386_TLS_GOTDESC a
+# CHECK-NEXT: 6: calll *(%eax)
+# CHECK-NEXT:   00000006: R_386_TLS_DESC_CALL a
+
+leal a@tlsdesc(%ebx), %eax
+call *a@tlscall(%eax)
+addl %gs:0, %eax
Index: test/MC/X86/tlsdesc-64.s
===================================================================
--- /dev/null
+++ test/MC/X86/tlsdesc-64.s
@@ -0,0 +1,16 @@
+# RUN: llvm-mc -triple x86_64-pc-linux-musl %s | FileCheck --check-prefix=PRINT %s
+
+# RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-musl %s -o %t
+# RUN: llvm-objdump -dr --no-show-raw-insn %t | FileCheck --match-full-lines %s
+
+# PRINT:      leaq a@tlsdesc(%rip), %rax
+# PRINT-NEXT: callq *a@tlscall(%rax)
+
+# CHECK:      0: leaq (%rip), %rax
+# CHECK-NEXT:   0000000000000003: R_X86_64_GOTPC32_TLSDESC a-4
+# CHECK-NEXT: 7: callq *(%rax)
+# CHECK-NEXT:   0000000000000007: R_X86_64_TLSDESC_CALL a
+
+leaq a@tlsdesc(%rip), %rax
+call *a@tlscall(%rax)
+addq %fs:0, %rax