diff --git a/include/llvm/BinaryFormat/Wasm.h b/include/llvm/BinaryFormat/Wasm.h
index 077913d7fa5..999f4a25781 100644
--- a/include/llvm/BinaryFormat/Wasm.h
+++ b/include/llvm/BinaryFormat/Wasm.h
@@ -359,6 +359,7 @@ enum WasmSymbolType : unsigned {
 
 enum WasmSegmentFlag : unsigned {
   WASM_SEG_FLAG_STRINGS = 0x1,
+  WASM_SEG_FLAG_TLS = 0x2,
 };
 
 // Kinds of event attributes.
diff --git a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index 54d65ccac50..31122295fa3 100644
--- a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -2009,11 +2009,14 @@ static const Comdat *getWasmComdat(const GlobalValue *GV) {
 static unsigned getWasmSectionFlags(SectionKind K) {
   unsigned Flags = 0;
 
-  // TODO(sbc): Add suport for K.isMergeableConst()
+  if (K.isThreadLocal())
+    Flags |= wasm::WASM_SEG_FLAG_TLS;
 
   if (K.isMergeableCString())
     Flags |= wasm::WASM_SEG_FLAG_STRINGS;
 
+  // TODO(sbc): Add suport for K.isMergeableConst()
+
   return Flags;
 }
 
diff --git a/lib/MC/MCParser/WasmAsmParser.cpp b/lib/MC/MCParser/WasmAsmParser.cpp
index fdf8c45ba5c..833530bef3b 100644
--- a/lib/MC/MCParser/WasmAsmParser.cpp
+++ b/lib/MC/MCParser/WasmAsmParser.cpp
@@ -100,6 +100,9 @@ public:
       case 'G':
         Group = true;
         break;
+      case 'T':
+        flags |= wasm::WASM_SEG_FLAG_TLS;
+        break;
       case 'S':
         flags |= wasm::WASM_SEG_FLAG_STRINGS;
         break;
diff --git a/lib/MC/MCSectionWasm.cpp b/lib/MC/MCSectionWasm.cpp
index 9faa4caad64..45991326326 100644
--- a/lib/MC/MCSectionWasm.cpp
+++ b/lib/MC/MCSectionWasm.cpp
@@ -69,6 +69,8 @@ void MCSectionWasm::PrintSwitchToSection(const MCAsmInfo &MAI, const Triple &T,
     OS << 'G';
   if (SegmentFlags & wasm::WASM_SEG_FLAG_STRINGS)
     OS << 'S';
+  if (SegmentFlags & wasm::WASM_SEG_FLAG_TLS)
+    OS << 'T';
 
   OS << '"';
 
diff --git a/lib/ObjectYAML/WasmYAML.cpp b/lib/ObjectYAML/WasmYAML.cpp
index 0017e7e609a..6b7357c4d1d 100644
--- a/lib/ObjectYAML/WasmYAML.cpp
+++ b/lib/ObjectYAML/WasmYAML.cpp
@@ -544,6 +544,7 @@ void ScalarBitSetTraits<WasmYAML::SegmentFlags>::bitset(
     IO &IO, WasmYAML::SegmentFlags &Value) {
 #define BCase(X) IO.bitSetCase(Value, #X, wasm::WASM_SEG_FLAG_##X)
   BCase(STRINGS);
+  BCase(TLS);
 #undef BCase
 }
 
diff --git a/test/CodeGen/WebAssembly/target-features-tls.ll b/test/CodeGen/WebAssembly/target-features-tls.ll
index e146bdae5f5..f5ec6842de7 100644
--- a/test/CodeGen/WebAssembly/target-features-tls.ll
+++ b/test/CodeGen/WebAssembly/target-features-tls.ll
@@ -23,4 +23,4 @@ target triple = "wasm32-unknown-unknown"
 ; BULK-MEM-NEXT: .int8 43
 ; BULK-MEM-NEXT: .int8 11
 ; BULK-MEM-NEXT: .ascii "bulk-memory"
-; BULK-MEM-NEXT: .tbss.foo,"",@
+; BULK-MEM-NEXT: .tbss.foo,"T",@
diff --git a/test/CodeGen/WebAssembly/tls-general-dynamic.ll b/test/CodeGen/WebAssembly/tls-general-dynamic.ll
index 16a312bd6ba..cb20066e14c 100644
--- a/test/CodeGen/WebAssembly/tls-general-dynamic.ll
+++ b/test/CodeGen/WebAssembly/tls-general-dynamic.ll
@@ -105,7 +105,7 @@ define void @tls_base_write(i8** %output) {
 }
 
 ; CHECK: .type tls,@object
-; TLS-NEXT: .section .tbss.tls,"",@
+; TLS-NEXT: .section .tbss.tls,"T",@
 ; NO-TLS-NEXT: .section .bss.tls,"",@
 ; CHECK-NEXT: .p2align 2
 ; CHECK-NEXT: tls:
diff --git a/test/CodeGen/WebAssembly/tls-local-exec.ll b/test/CodeGen/WebAssembly/tls-local-exec.ll
index 7cc043a13ac..c6ae34b7fc8 100644
--- a/test/CodeGen/WebAssembly/tls-local-exec.ll
+++ b/test/CodeGen/WebAssembly/tls-local-exec.ll
@@ -72,7 +72,7 @@ define i32 @tls_size() {
 }
 
 ; CHECK: .type tls,@object
-; TLS-NEXT: .section .tbss.tls,"",@
+; TLS-NEXT: .section .tbss.tls,"T",@
 ; NO-TLS-NEXT: .section .bss.tls,"",@
 ; CHECK-NEXT: .p2align 2
 ; CHECK-NEXT: tls:
diff --git a/test/MC/WebAssembly/tls.s b/test/MC/WebAssembly/tls.s
index f1dba829944..2df245ff938 100644
--- a/test/MC/WebAssembly/tls.s
+++ b/test/MC/WebAssembly/tls.s
@@ -5,15 +5,26 @@
 tls_store:
   .functype tls_store (i32) -> ()
   # CHECK: global.get __tls_base
-  # CHECK-NEXT: i32.const tls@TLSREL
+  # CHECK-NEXT: i32.const tls1@TLSREL
   # CHECK-NEXT: i32.add
   # CHECK-NEXT: i32.store 0
   global.get __tls_base
-  i32.const tls@TLSREL
+  i32.const tls1@TLSREL
   i32.add
   i32.store 0
   end_function
 
+.section .tls.foo,"T",@
+# CHECK: .tls.foo,"T",@
+tls1:
+  .int32 42
+  .size tls1, 4
+
+.section custom_tls,"T",@
+# CHECK: custom_tls,"T",@
+tls2:
+  .int32 43
+  .size tls2, 4
 
 #      CHECK-OBJ:  - Type:            CODE
 # CHECK-OBJ-NEXT:    Relocations:
@@ -39,5 +50,22 @@ tls_store:
 # CHECK-OBJ-NEXT:        Flags:           [ UNDEFINED ]
 # CHECK-OBJ-NEXT:      - Index:           2
 # CHECK-OBJ-NEXT:        Kind:            DATA
-# CHECK-OBJ-NEXT:        Name:            tls
-# CHECK-OBJ-NEXT:        Flags:           [ UNDEFINED ]
+# CHECK-OBJ-NEXT:        Name:            tls1
+# CHECK-OBJ-NEXT:        Flags:           [ BINDING_LOCAL ]
+# CHECK-OBJ-NEXT:        Segment:         0
+# CHECK-OBJ-NEXT:        Size:            4
+# CHECK-OBJ-NEXT:      - Index:           3
+# CHECK-OBJ-NEXT:        Kind:            DATA
+# CHECK-OBJ-NEXT:        Name:            tls2
+# CHECK-OBJ-NEXT:        Flags:           [ BINDING_LOCAL ]
+# CHECK-OBJ-NEXT:        Segment:         1
+# CHECK-OBJ-NEXT:        Size:            4
+# CHECK-OBJ-NEXT:    SegmentInfo:
+# CHECK-OBJ-NEXT:      - Index:           0
+# CHECK-OBJ-NEXT:        Name:            .tls.foo
+# CHECK-OBJ-NEXT:        Alignment:       0
+# CHECK-OBJ-NEXT:        Flags:           [ TLS ]
+# CHECK-OBJ-NEXT:      - Index:           1
+# CHECK-OBJ-NEXT:        Name:            custom_tls
+# CHECK-OBJ-NEXT:        Alignment:       0
+# CHECK-OBJ-NEXT:        Flags:           [ TLS ]