diff --git a/gcc/doc/libgcc.texi b/gcc/doc/libgcc.texi
index 73aa803..7611347 100644
--- a/gcc/doc/libgcc.texi
+++ b/gcc/doc/libgcc.texi
@@ -218,6 +218,13 @@ These functions return the number of bits set in @var{a}.
 These functions return the @var{a} byteswapped.
 @end deftypefn
 
+@deftypefn {Runtime Function} int8_t __bitrevqi2 (int8_t @var{a})
+@deftypefnx {Runtime Function} int16_t __bitrevhi2 (int16_t @var{a})
+@deftypefnx {Runtime Function} int32_t __bitrevsi2 (int32_t @var{a})
+@deftypefnx {Runtime Function} int64_t __bitrevdi2 (int64_t @var{a})
+These functions return the bit reversed @var{a}.
+@end deftypefn
+
 @node Soft float library routines
 @section Routines for floating point emulation
 @cindex soft float library
diff --git a/libgcc/Makefile.in b/libgcc/Makefile.in
index 6c4dc79..67c54df 100644
--- a/libgcc/Makefile.in
+++ b/libgcc/Makefile.in
@@ -446,7 +446,7 @@ lib2funcs = _muldi3 _negdi2 _lshrdi3 _ashldi3 _ashrdi3 _cmpdi2 _ucmpdi2	   \
 	    _paritysi2 _paritydi2 _powisf2 _powidf2 _powixf2 _powitf2	   \
 	    _mulhc3 _mulsc3 _muldc3 _mulxc3 _multc3 _divhc3 _divsc3	   \
 	    _divdc3 _divxc3 _divtc3 _bswapsi2 _bswapdi2 _clrsbsi2	   \
-	    _clrsbdi2
+	    _clrsbdi2 _bitrevqi2 _bitrevhi2 _bitrevsi2 _bitrevdi2
 
 # The floating-point conversion routines that involve a single-word integer.
 # XX stands for the integer mode.
diff --git a/libgcc/libgcc-std.ver.in b/libgcc/libgcc-std.ver.in
index c4f87a5..2198b0e 100644
--- a/libgcc/libgcc-std.ver.in
+++ b/libgcc/libgcc-std.ver.in
@@ -1944,3 +1944,12 @@ GCC_7.0.0 {
   __PFX__divmoddi4
   __PFX__divmodti4
 }
+
+%inherit GCC_14.0.0 GCC_7.0.0
+GCC_14.0.0 {
+  # bit reversal functions
+  __PFX__bitrevqi2
+  __PFX__bitrevhi2
+  __PFX__bitrevsi2
+  __PFX__bitrevdi2
+}
diff --git a/libgcc/libgcc2.c b/libgcc/libgcc2.c
index e0017d1..2bef2a1 100644
--- a/libgcc/libgcc2.c
+++ b/libgcc/libgcc2.c
@@ -488,6 +488,54 @@ __bswapdi2 (DItype u)
 	  | (((u) & 0x00000000000000ffull) << 56));
 }
 #endif
+
+#ifdef L_bitrevqi2
+QItype
+__bitrevqi2 (QItype x)
+{
+  UQItype u = x;
+  u = (((u) >> 1) & 0x55) | (((u) & 0x55) << 1);
+  u = (((u) >> 2) & 0x33) | (((u) & 0x33) << 2);
+  return ((u) >> 4) | ((u) << 4);
+}
+#endif
+#ifdef L_bitrevhi2
+HItype
+__bitrevhi2 (HItype x)
+{
+  UHItype u = x;
+  u = (((u) >> 1) & 0x5555) | (((u) & 0x5555) << 1);
+  u = (((u) >> 2) & 0x3333) | (((u) & 0x3333) << 2);
+  u = (((u) >> 4) & 0x0f0f) | (((u) & 0x0f0f) << 4);
+  return ((u) >> 8) | ((u) << 8);
+}
+#endif
+#ifdef L_bitrevsi2
+SItype
+__bitrevsi2 (SItype x)
+{
+  USItype u = x;
+  u = (((u) >> 1) & 0x55555555) | (((u) & 0x55555555) << 1);
+  u = (((u) >> 2) & 0x33333333) | (((u) & 0x33333333) << 2);
+  u = (((u) >> 4) & 0x0f0f0f0f) | (((u) & 0x0f0f0f0f) << 4);
+  return __bswapsi2 (u);
+}
+#endif
+#ifdef L_bitrevdi2
+DItype
+__bitrevdi2 (DItype x)
+{
+  UDItype u = x;
+  u = (((u) >> 1) & 0x5555555555555555ll)
+      | (((u) & 0x5555555555555555ll) << 1);
+  u = (((u) >> 2) & 0x3333333333333333ll)
+      | (((u) & 0x3333333333333333ll) << 2);
+  u = (((u) >> 4) & 0x0f0f0f0f0f0f0f0fll)
+      | (((u) & 0x0f0f0f0f0f0f0f0fll) << 4);
+  return __bswapdi2 (u);
+}
+#endif
+
 #ifdef L_ffssi2
 #undef int
 int
diff --git a/libgcc/libgcc2.h b/libgcc/libgcc2.h
index 3ec9bbd..e1abc0d 100644
--- a/libgcc/libgcc2.h
+++ b/libgcc/libgcc2.h
@@ -338,6 +338,10 @@ typedef int shift_count_type __attribute__((mode (__libgcc_shift_count__)));
 #define __udiv_w_sdiv		__N(udiv_w_sdiv)
 #define __clear_cache		__N(clear_cache)
 #define __enable_execute_stack	__N(enable_execute_stack)
+#define __bitrevqi2		__N(bitrevqi2)
+#define __bitrevhi2		__N(bitrevhi2)
+#define __bitrevsi2		__N(bitrevsi2)
+#define __bitrevdi2		__N(bitrevdi2)
 
 #ifndef __powisf2
 #define __powisf2		__N(powisf2)
@@ -426,6 +430,15 @@ extern DWtype __subvDI3 (DWtype, DWtype);
 extern DWtype __mulvDI3 (DWtype, DWtype);
 extern DWtype __negvDI2 (DWtype);
 
+extern QItype __bitrevqi2 (QItype);
+extern HItype __bitrevhi2 (HItype);
+#if MIN_UNITS_PER_WORD > 1
+extern SItype __bitrevsi2 (SItype);
+#endif
+#if __SIZEOF_LONG_LONG__ > 4
+extern DItype __bitrevdi2 (DItype);
+#endif
+
 #ifdef COMPAT_SIMODE_TRAPPING_ARITHMETIC
 #define __absvsi2	__N(absvsi2)
 #define __negvsi2	__N(negvsi2)