diff --git a/gcc/config/loongarch/loongarch-builtins.cc b/gcc/config/loongarch/loongarch-builtins.cc
index a4a7dbec9..2d9743d86 100644
--- a/gcc/config/loongarch/loongarch-builtins.cc
+++ b/gcc/config/loongarch/loongarch-builtins.cc
@@ -2440,11 +2440,6 @@ loongarch_init_builtins (void)
   unsigned int i;
   tree type;
 
-  /* Register the type float128_type_node as a built-in type and
-     give it an alias "__float128".  */
-  (*lang_hooks.types.register_builtin_type) (float128_type_node,
-					    "__float128");
-
   /* Iterate through all of the bdesc arrays, initializing all of the
      builtin functions.  */
   for (i = 0; i < ARRAY_SIZE (loongarch_builtins); i++)
diff --git a/gcc/config/loongarch/loongarch-c.cc b/gcc/config/loongarch/loongarch-c.cc
index c9b11a042..76c8ea8db 100644
--- a/gcc/config/loongarch/loongarch-c.cc
+++ b/gcc/config/loongarch/loongarch-c.cc
@@ -117,17 +117,6 @@ loongarch_cpu_cpp_builtins (cpp_reader *pfile)
       builtin_define ("__loongarch_simd_width=256");
     }
 
-  /* Add support for FLOAT128_TYPE on the LoongArch architecture.  */
-  builtin_define ("__FLOAT128_TYPE__");
-
-  /* Map the old _Float128 'q' builtins into the new 'f128' builtins.  */
-  builtin_define ("__builtin_fabsq=__builtin_fabsf128");
-  builtin_define ("__builtin_copysignq=__builtin_copysignf128");
-  builtin_define ("__builtin_nanq=__builtin_nanf128");
-  builtin_define ("__builtin_nansq=__builtin_nansf128");
-  builtin_define ("__builtin_infq=__builtin_inff128");
-  builtin_define ("__builtin_huge_valq=__builtin_huge_valf128");
-
   /* Native Data Sizes.  */
   builtin_define_with_int_value ("_LOONGARCH_SZINT", INT_TYPE_SIZE);
   builtin_define_with_int_value ("_LOONGARCH_SZLONG", LONG_TYPE_SIZE);
diff --git a/gcc/config/loongarch/loongarch.cc b/gcc/config/loongarch/loongarch.cc
index baa9831aa..ae074edbd 100644
--- a/gcc/config/loongarch/loongarch.cc
+++ b/gcc/config/loongarch/loongarch.cc
@@ -9712,13 +9712,10 @@ expand_perm_const_2_end:
 /* Implement TARGET_VECTORIZE_VEC_PERM_CONST.  */
 
 static bool
-loongarch_vectorize_vec_perm_const (machine_mode vmode, machine_mode op_mode,
+loongarch_vectorize_vec_perm_const (machine_mode vmode,
 				    rtx target, rtx op0, rtx op1,
 				    const vec_perm_indices &sel)
 {
-  if (vmode != op_mode)
-    return false;
-
   struct expand_vec_perm_d d;
   int i, nelt, which;
   unsigned char orig_perm[MAX_VECT_LEN];
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index bb19d0f27..1d1bac255 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -1085,10 +1085,10 @@ types.
 As an extension, GNU C and GNU C++ support additional floating
 types, which are not supported by all targets.
 @itemize @bullet
-@item @code{__float128} is available on i386, x86_64, IA-64, LoongArch
-and hppa HP-UX, as well as on PowerPC GNU/Linux targets that enable
+@item @code{__float128} is available on i386, x86_64, IA-64, and
+hppa HP-UX, as well as on PowerPC GNU/Linux targets that enable
 the vector scalar (VSX) instruction set.  @code{__float128} supports
-the 128-bit floating type.  On i386, x86_64, PowerPC, LoongArch and IA-64,
+the 128-bit floating type.  On i386, x86_64, PowerPC, and IA-64
 other than HP-UX, @code{__float128} is an alias for @code{_Float128}.
 On hppa and IA-64 HP-UX, @code{__float128} is an alias for @code{long
 double}.
@@ -16257,20 +16257,6 @@ function you need to include @code{larchintrin.h}.
     void __break (imm0_32767)
 @end smallexample
 
-Additional built-in functions are available for LoongArch family
-processors to efficiently use 128-bit floating-point (__float128)
-values.
-
-The following are the basic built-in functions supported.
-@smallexample
-__float128 __builtin_fabsq (__float128);
-__float128 __builtin_copysignq (__float128, __float128);
-__float128 __builtin_infq (void);
-__float128 __builtin_huge_valq (void);
-__float128 __builtin_nanq (void);
-__float128 __builtin_nansq (void);
-@end smallexample
-
 @node MIPS DSP Built-in Functions
 @subsection MIPS DSP Built-in Functions
 
diff --git a/gcc/testsuite/gcc.target/loongarch/math-float-128.c b/gcc/testsuite/gcc.target/loongarch/math-float-128.c
deleted file mode 100644
index 387566a57..000000000
--- a/gcc/testsuite/gcc.target/loongarch/math-float-128.c
+++ /dev/null
@@ -1,81 +0,0 @@
-/* { dg-do compile } */
-/* { dg-options " -march=loongarch64 -O2 " } */
-/* { dg-final { scan-assembler-not "my_fabsq2:.*\\bl\t%plt\\(__builtin_fabsq\\).*my_fabsq2" } } */
-/* { dg-final { scan-assembler-not "my_copysignq2:.*\\bl\t%plt\\(__builtin_copysignq\\).*my_copysignq2" } } */
-/* { dg-final { scan-assembler-not "my_infq2:.*\\bl\t%plt\\(__builtin_infq\\).*my_infq2" } } */
-/* { dg-final { scan-assembler-not "my_huge_valq2:.*\\bl\t%plt\\(__builtin_huge_valq\\).*my_huge_valq2" } } */
-/* { dg-final { scan-assembler-not "my_nanq2:.*\\bl\t%plt\\(__builtin_nanq\\).*my_nanq2" } } */
-/* { dg-final { scan-assembler-not "my_nansq2:.*\\bl\t%plt\\(__builtin_nansq\\).*my_nansq2" } } */
-
-__float128
-my_fabsq1 (__float128 a)
-{
-  return __builtin_fabsq (a);
-}
-
-_Float128
-my_fabsq2 (_Float128 a)
-{
-  return __builtin_fabsq (a);
-}
-
-__float128
-my_copysignq1 (__float128 a, __float128 b)
-{
-  return __builtin_copysignq (a, b);
-}
-
-_Float128
-my_copysignq2 (_Float128 a, _Float128 b)
-{
-  return __builtin_copysignq (a, b);
-}
-
-__float128
-my_infq1 (void)
-{
-  return __builtin_infq ();
-}
-
-_Float128
-my_infq2 (void)
-{
-  return __builtin_infq ();
-}
-
-__float128
-my_huge_valq1 (void)
-{
-  return __builtin_huge_valq ();
-}
-
-_Float128
-my_huge_valq2 (void)
-{
-  return __builtin_huge_valq ();
-}
-
-__float128
-my_nanq1 (void)
-{
-  return __builtin_nanq ("");
-}
-
-_Float128
-my_nanq2 (void)
-{
-  return __builtin_nanq ("");
-}
-
-__float128
-my_nansq1 (void)
-{
-  return __builtin_nansq ("");
-}
-
-_Float128
-my_nansq2 (void)
-{
-  return __builtin_nansq ("");
-}
-