Index: lib/builtins/arm/bswapdi2.S
===================================================================
--- lib/builtins/arm/bswapdi2.S
+++ lib/builtins/arm/bswapdi2.S
@@ -11,6 +11,9 @@
 
 	.syntax unified
 	.text
+#if __ARM_ARCH_ISA_THUMB == 2
+	.thumb
+#endif
 
 //
 // extern uint64_t __bswapdi2(uint64_t);
Index: lib/builtins/arm/bswapsi2.S
===================================================================
--- lib/builtins/arm/bswapsi2.S
+++ lib/builtins/arm/bswapsi2.S
@@ -11,6 +11,9 @@
 
 	.syntax unified
 	.text
+#if __ARM_ARCH_ISA_THUMB == 2
+	.thumb
+#endif
 
 //
 // extern uint32_t __bswapsi2(uint32_t);
Index: lib/builtins/arm/clzdi2.S
===================================================================
--- lib/builtins/arm/clzdi2.S
+++ lib/builtins/arm/clzdi2.S
@@ -15,6 +15,10 @@
 
 	.syntax unified
 	.text
+#if __ARM_ARCH_ISA_THUMB == 2
+	.thumb
+#endif
+
 
 	.p2align	2
 DEFINE_COMPILERRT_FUNCTION(__clzdi2)
Index: lib/builtins/arm/clzsi2.S
===================================================================
--- lib/builtins/arm/clzsi2.S
+++ lib/builtins/arm/clzsi2.S
@@ -15,6 +15,9 @@
 
 	.syntax unified
 	.text
+#if __ARM_ARCH_ISA_THUMB == 2
+	.thumb
+#endif
 
 	.p2align	2
 DEFINE_COMPILERRT_FUNCTION(__clzsi2)
Index: lib/builtins/arm/divmodsi4.S
===================================================================
--- lib/builtins/arm/divmodsi4.S
+++ lib/builtins/arm/divmodsi4.S
@@ -23,6 +23,9 @@
 
 	.syntax unified
 	.text
+#if __ARM_ARCH_ISA_THUMB == 2
+	.thumb
+#endif
 
 	.p2align 3
 DEFINE_COMPILERRT_FUNCTION(__divmodsi4)
Index: lib/builtins/arm/divsi3.S
===================================================================
--- lib/builtins/arm/divsi3.S
+++ lib/builtins/arm/divsi3.S
@@ -22,6 +22,9 @@
 
 	.syntax unified
 	.text
+#if __ARM_ARCH_ISA_THUMB == 2
+	.thumb
+#endif
 
 	.p2align 3
 // Ok, APCS and AAPCS agree on 32 bit args, so it's safe to use the same routine.
Index: lib/builtins/arm/modsi3.S
===================================================================
--- lib/builtins/arm/modsi3.S
+++ lib/builtins/arm/modsi3.S
@@ -22,6 +22,9 @@
 
 	.syntax unified
 	.text
+#if __ARM_ARCH_ISA_THUMB == 2
+	.thumb
+#endif
 
 	.p2align 3
 DEFINE_COMPILERRT_FUNCTION(__modsi3)
Index: lib/builtins/arm/udivmodsi4.S
===================================================================
--- lib/builtins/arm/udivmodsi4.S
+++ lib/builtins/arm/udivmodsi4.S
@@ -16,6 +16,9 @@
 
 	.syntax unified
 	.text
+#if __ARM_ARCH_ISA_THUMB == 2
+	.thumb
+#endif
 
 	.p2align 2
 DEFINE_COMPILERRT_FUNCTION(__udivmodsi4)
Index: lib/builtins/arm/udivsi3.S
===================================================================
--- lib/builtins/arm/udivsi3.S
+++ lib/builtins/arm/udivsi3.S
@@ -16,6 +16,9 @@
 
 	.syntax unified
 	.text
+#if __ARM_ARCH_ISA_THUMB == 2
+	.thumb
+#endif
 
 	.p2align 2
 DEFINE_AEABI_FUNCTION_ALIAS(__aeabi_uidiv, __udivsi3)
Index: lib/builtins/arm/umodsi3.S
===================================================================
--- lib/builtins/arm/umodsi3.S
+++ lib/builtins/arm/umodsi3.S
@@ -16,6 +16,9 @@
 
 	.syntax unified
 	.text
+#if __ARM_ARCH_ISA_THUMB == 2
+	.thumb
+#endif
 
 	.p2align 2
 DEFINE_COMPILERRT_FUNCTION(__umodsi3)