diff --git a/compiler-rt/lib/builtins/mulodi4.c b/compiler-rt/lib/builtins/int_mulo_impl.inc
copy from compiler-rt/lib/builtins/mulodi4.c
copy to compiler-rt/lib/builtins/int_mulo_impl.inc
--- a/compiler-rt/lib/builtins/mulodi4.c
+++ b/compiler-rt/lib/builtins/int_mulo_impl.inc
@@ -1,4 +1,4 @@
-//===-- mulodi4.c - Implement __mulodi4 -----------------------------------===//
+//===-- int_mulo_impl.inc - Implement __mulo[sdt]i4 ---------------*- C -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
@@ -6,7 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// This file implements __mulodi4 for the compiler_rt library.
+// Helper used by __mulosi4, __mulodi4 and __muloti4.
 //
 //===----------------------------------------------------------------------===//
 
@@ -16,12 +16,12 @@
 
 // Effects: sets *overflow to 1  if a * b overflows
 
-COMPILER_RT_ABI di_int __mulodi4(di_int a, di_int b, int *overflow) {
-  const int N = (int)(sizeof(di_int) * CHAR_BIT);
-  const di_int MIN = (di_int)1 << (N - 1);
-  const di_int MAX = ~MIN;
+static __inline fixint_t __muloXi4(fixint_t a, fixint_t b, int *overflow) {
+  const int N = (int)(sizeof(fixint_t) * CHAR_BIT);
+  const fixint_t MIN = (fixint_t)1 << (N - 1);
+  const fixint_t MAX = ~MIN;
   *overflow = 0;
-  di_int result = a * b;
+  fixint_t result = a * b;
   if (a == MIN) {
     if (b != 0 && b != 1)
       *overflow = 1;
@@ -32,10 +32,10 @@
       *overflow = 1;
     return result;
   }
-  di_int sa = a >> (N - 1);
-  di_int abs_a = (a ^ sa) - sa;
-  di_int sb = b >> (N - 1);
-  di_int abs_b = (b ^ sb) - sb;
+  fixint_t sa = a >> (N - 1);
+  fixint_t abs_a = (a ^ sa) - sa;
+  fixint_t sb = b >> (N - 1);
+  fixint_t abs_b = (b ^ sb) - sb;
   if (abs_a < 2 || abs_b < 2)
     return result;
   if (sa == sb) {
diff --git a/compiler-rt/lib/builtins/mulodi4.c b/compiler-rt/lib/builtins/mulodi4.c
--- a/compiler-rt/lib/builtins/mulodi4.c
+++ b/compiler-rt/lib/builtins/mulodi4.c
@@ -10,40 +10,13 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "int_lib.h"
+#define fixint_t di_int
+#include "int_mulo_impl.inc"
 
 // Returns: a * b
 
 // Effects: sets *overflow to 1  if a * b overflows
 
 COMPILER_RT_ABI di_int __mulodi4(di_int a, di_int b, int *overflow) {
-  const int N = (int)(sizeof(di_int) * CHAR_BIT);
-  const di_int MIN = (di_int)1 << (N - 1);
-  const di_int MAX = ~MIN;
-  *overflow = 0;
-  di_int result = a * b;
-  if (a == MIN) {
-    if (b != 0 && b != 1)
-      *overflow = 1;
-    return result;
-  }
-  if (b == MIN) {
-    if (a != 0 && a != 1)
-      *overflow = 1;
-    return result;
-  }
-  di_int sa = a >> (N - 1);
-  di_int abs_a = (a ^ sa) - sa;
-  di_int sb = b >> (N - 1);
-  di_int abs_b = (b ^ sb) - sb;
-  if (abs_a < 2 || abs_b < 2)
-    return result;
-  if (sa == sb) {
-    if (abs_a > MAX / abs_b)
-      *overflow = 1;
-  } else {
-    if (abs_a > MIN / -abs_b)
-      *overflow = 1;
-  }
-  return result;
+  return __muloXi4(a, b, overflow);
 }
diff --git a/compiler-rt/lib/builtins/mulosi4.c b/compiler-rt/lib/builtins/mulosi4.c
--- a/compiler-rt/lib/builtins/mulosi4.c
+++ b/compiler-rt/lib/builtins/mulosi4.c
@@ -10,40 +10,13 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "int_lib.h"
+#define fixint_t si_int
+#include "int_mulo_impl.inc"
 
 // Returns: a * b
 
 // Effects: sets *overflow to 1  if a * b overflows
 
 COMPILER_RT_ABI si_int __mulosi4(si_int a, si_int b, int *overflow) {
-  const int N = (int)(sizeof(si_int) * CHAR_BIT);
-  const si_int MIN = (si_int)1 << (N - 1);
-  const si_int MAX = ~MIN;
-  *overflow = 0;
-  si_int result = a * b;
-  if (a == MIN) {
-    if (b != 0 && b != 1)
-      *overflow = 1;
-    return result;
-  }
-  if (b == MIN) {
-    if (a != 0 && a != 1)
-      *overflow = 1;
-    return result;
-  }
-  si_int sa = a >> (N - 1);
-  si_int abs_a = (a ^ sa) - sa;
-  si_int sb = b >> (N - 1);
-  si_int abs_b = (b ^ sb) - sb;
-  if (abs_a < 2 || abs_b < 2)
-    return result;
-  if (sa == sb) {
-    if (abs_a > MAX / abs_b)
-      *overflow = 1;
-  } else {
-    if (abs_a > MIN / -abs_b)
-      *overflow = 1;
-  }
-  return result;
+  return __muloXi4(a, b, overflow);
 }
diff --git a/compiler-rt/lib/builtins/muloti4.c b/compiler-rt/lib/builtins/muloti4.c
--- a/compiler-rt/lib/builtins/muloti4.c
+++ b/compiler-rt/lib/builtins/muloti4.c
@@ -18,36 +18,11 @@
 
 // Effects: sets *overflow to 1  if a * b overflows
 
+#define fixint_t ti_int
+#include "int_mulo_impl.inc"
+
 COMPILER_RT_ABI ti_int __muloti4(ti_int a, ti_int b, int *overflow) {
-  const int N = (int)(sizeof(ti_int) * CHAR_BIT);
-  const ti_int MIN = (ti_int)1 << (N - 1);
-  const ti_int MAX = ~MIN;
-  *overflow = 0;
-  ti_int result = a * b;
-  if (a == MIN) {
-    if (b != 0 && b != 1)
-      *overflow = 1;
-    return result;
-  }
-  if (b == MIN) {
-    if (a != 0 && a != 1)
-      *overflow = 1;
-    return result;
-  }
-  ti_int sa = a >> (N - 1);
-  ti_int abs_a = (a ^ sa) - sa;
-  ti_int sb = b >> (N - 1);
-  ti_int abs_b = (b ^ sb) - sb;
-  if (abs_a < 2 || abs_b < 2)
-    return result;
-  if (sa == sb) {
-    if (abs_a > MAX / abs_b)
-      *overflow = 1;
-  } else {
-    if (abs_a > MIN / -abs_b)
-      *overflow = 1;
-  }
-  return result;
+  return __muloXi4(a, b, overflow);
 }
 
 #endif // CRT_HAS_128BIT