--- a/compiler-rt/lib/builtins/CMakeLists.txt
+++ b/compiler-rt/lib/builtins/CMakeLists.txt
@@ -362,6 +362,7 @@
 
   set(i386_SOURCES
     ${GENERIC_SOURCES}
+    ${GENERIC_TF_SOURCES}
     ${x86_ARCH_SOURCES}
     i386/ashldi3.S
     i386/ashrdi3.S
@@ -1012,9 +1013,9 @@
         list(APPEND BUILTIN_CFLAGS_${arch} -fomit-frame-pointer -DCOMPILER_RT_ARMHF_TARGET)
       endif()
 
-      # For RISCV32 and 32-bit SPARC, we must force enable int128 for compiling long
-      # double routines.
-      if (COMPILER_RT_ENABLE_SOFTWARE_INT128 OR ("${arch}" MATCHES "riscv32|sparc$"
+      # For i386, RISCV32 and 32-bit SPARC, we must force enable int128 for
+      # compiling long double routines.
+      if (COMPILER_RT_ENABLE_SOFTWARE_INT128 OR ("${arch}" MATCHES "i386|riscv32|sparc$"
         AND NOT CMAKE_COMPILER_IS_GNUCC))
         list(APPEND BUILTIN_CFLAGS_${arch} -fforce-enable-int128)
       endif()

--- a/compiler-rt/lib/builtins/extendxftf2.c
+++ b/compiler-rt/lib/builtins/extendxftf2.c
@@ -12,7 +12,8 @@
 #define QUAD_PRECISION
 #include "fp_lib.h"
 
-#if defined(CRT_HAS_TF_MODE) && __LDBL_MANT_DIG__ == 64 && defined(__x86_64__)
+#if defined(CRT_HAS_TF_MODE) && __LDBL_MANT_DIG__ == 64 &&                    \
+    (defined(__x86_64__) || defined(__i386__))
 #define SRC_80
 #define DST_QUAD
 #include "fp_extend_impl.inc"

--- a/compiler-rt/lib/builtins/trunctfxf2.c
+++ b/compiler-rt/lib/builtins/trunctfxf2.c
@@ -12,7 +12,8 @@
 #define QUAD_PRECISION
 #include "fp_lib.h"
 
-#if defined(CRT_HAS_TF_MODE) && __LDBL_MANT_DIG__ == 64 && defined(__x86_64__)
+#if defined(CRT_HAS_TF_MODE) && __LDBL_MANT_DIG__ == 64 &&                    \
+    (defined(__x86_64__) || defined(__i386__))
 
 #define SRC_QUAD
 #define DST_80

--- a/compiler-rt/lib/builtins/truncxfbf2.c
+++ b/compiler-rt/lib/builtins/truncxfbf2.c
@@ -6,7 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#if defined(CRT_HAS_TF_MODE) && __LDBL_MANT_DIG__ == 64 && defined(__x86_64__)
+#if defined(CRT_HAS_TF_MODE) && __LDBL_MANT_DIG__ == 64 &&                    \
+    (defined(__x86_64__) || defined(__i386__))
 #define SRC_80
 #define DST_BFLOAT
 #include "fp_trunc_impl.inc"