diff mbox series

[v1,1/3] x86: Add support to build strcmp/strlen/strchr with explicit ISA level

Message ID 20220713230945.1866193-1-goldstein.w.n@gmail.com
State New
Headers show
Series [v1,1/3] x86: Add support to build strcmp/strlen/strchr with explicit ISA level | expand

Commit Message

Noah Goldstein July 13, 2022, 11:09 p.m. UTC
This commit follows the same pattern of earlier commits:

1. Refactor files so that all implementations are in the multiarch
   directory
    - i.e move strchr's SSE2 implementation from strchr.S to
      multiarch/strchr-sse2.S

    - The non-multiarch file now only includes one of the
      implementations in the multiarch directory based on the compiled
      ISA level (only used for non-multiarch builds.  Otherwise we go
      through the ifunc selector).

2. Add ISA level build guards to different implementations.
    - I.e strcmp-avx2.S which is ISA level 3 will only build if
      compiled ISA level <= 3. Otherwise there is no reason to
      include it as we will always use one of the ISA level 4
      implementations (strcmp-evex.S).

3. Add new multiarch/rtld-<func>.S that just include the
   non-multiarch <func>.S which will in turn select the best
   implementation based on the compiled ISA level.
    - i.e multiarch/rtld-strlen.S

4. Refactor the ifunc selector and ifunc implementation list to use
   the ISA level aware wrapper macros that allow functions below the
   compiled ISA level (with a guranteed replacement) to be skipped.

Tested with and without multiarch on x86_64 for ISA levels:
{generic, x86-64-v2, x86-64-v3, x86-64-v4}

And m32 with and without multiarch.
---
 sysdeps/x86/isa-level.h                       |  10 +
 sysdeps/x86_64/Makefile                       |   6 +
 sysdeps/x86_64/memrchr.S                      |  10 +-
 sysdeps/x86_64/multiarch/Makefile             |   2 -
 sysdeps/x86_64/multiarch/ifunc-avx2.h         |  22 +-
 sysdeps/x86_64/multiarch/ifunc-impl-list.c    | 648 ++++++++++--------
 sysdeps/x86_64/multiarch/ifunc-strcasecmp.h   |  33 +-
 sysdeps/x86_64/multiarch/ifunc-wcslen.h       |  27 +-
 sysdeps/x86_64/multiarch/memrchr-avx2.S       |   4 +-
 sysdeps/x86_64/multiarch/memrchr-evex.S       |   4 +-
 sysdeps/x86_64/multiarch/memrchr-sse2.S       |  19 +-
 .../x86_64/multiarch/strcasecmp_l-avx2-rtm.S  |  17 +-
 sysdeps/x86_64/multiarch/strcasecmp_l-avx2.S  |   3 -
 sysdeps/x86_64/multiarch/strcasecmp_l-evex.S  |   3 -
 sysdeps/x86_64/multiarch/strcasecmp_l-sse2.S  |   1 +
 sysdeps/x86_64/multiarch/strchr-avx2.S        |   4 +-
 sysdeps/x86_64/multiarch/strchr-evex.S        |   4 +-
 sysdeps/x86_64/multiarch/strchr-sse2-no-bsf.S |   6 +-
 sysdeps/x86_64/multiarch/strchr-sse2.S        |   7 +-
 sysdeps/x86_64/multiarch/strchr.c             |  30 +-
 sysdeps/x86_64/multiarch/strchrnul-avx2.S     |   7 +-
 sysdeps/x86_64/multiarch/strchrnul-evex.S     |   7 +-
 sysdeps/x86_64/multiarch/strchrnul-sse2.S     |   8 +-
 sysdeps/x86_64/multiarch/strcmp-avx2-rtm.S    |   5 +-
 sysdeps/x86_64/multiarch/strcmp-avx2.S        |  22 +-
 sysdeps/x86_64/multiarch/strcmp-evex.S        |  20 +-
 .../x86_64/multiarch/strcmp-sse2-unaligned.S  |  18 +-
 sysdeps/x86_64/multiarch/strcmp-sse2.S        |   6 +-
 sysdeps/x86_64/multiarch/strcmp-sse4_2.S      |   6 +-
 sysdeps/x86_64/multiarch/strcmp.c             |  37 +-
 sysdeps/x86_64/multiarch/strlen-avx2.S        |   4 +-
 sysdeps/x86_64/multiarch/strlen-evex-base.S   |   6 +-
 sysdeps/x86_64/multiarch/strlen-evex.S        |   4 +-
 sysdeps/x86_64/multiarch/strlen-sse2.S        |  17 +-
 .../x86_64/multiarch/strncase_l-avx2-rtm.S    |  18 +-
 sysdeps/x86_64/multiarch/strncase_l-avx2.S    |   7 +-
 sysdeps/x86_64/multiarch/strncase_l-evex.S    |   4 -
 sysdeps/x86_64/multiarch/strncmp-avx2-rtm.S   |   2 -
 sysdeps/x86_64/multiarch/strncmp-avx2.S       |   3 +-
 sysdeps/x86_64/multiarch/strncmp-evex.S       |   1 -
 sysdeps/x86_64/multiarch/strncmp.c            |  27 +-
 sysdeps/x86_64/multiarch/strnlen-avx2.S       |   6 +-
 sysdeps/x86_64/multiarch/strnlen-evex.S       |   6 +-
 sysdeps/x86_64/multiarch/strnlen-sse2.S       |  10 +-
 sysdeps/x86_64/multiarch/strrchr-avx2.S       |   4 +-
 sysdeps/x86_64/multiarch/strrchr-evex.S       |   4 +-
 sysdeps/x86_64/multiarch/strrchr-sse2.S       |  99 +--
 .../x86_64/multiarch/strstr-sse2-unaligned.S  |   3 +-
 sysdeps/x86_64/multiarch/wcschr-avx2.S        |   7 +-
 sysdeps/x86_64/multiarch/wcschr-evex.S        |   7 +-
 sysdeps/x86_64/multiarch/wcschr-sse2.S        |  11 +-
 sysdeps/x86_64/multiarch/wcscmp-avx2-rtm.S    |   1 -
 sysdeps/x86_64/multiarch/wcscmp-avx2.S        |   1 -
 sysdeps/x86_64/multiarch/wcscmp-evex.S        |   1 -
 sysdeps/x86_64/multiarch/wcscmp-sse2.S        |  14 +-
 sysdeps/x86_64/multiarch/wcslen-avx2.S        |   6 +-
 sysdeps/x86_64/multiarch/wcslen-evex.S        |   6 +-
 sysdeps/x86_64/multiarch/wcslen-sse2.S        |  15 +-
 sysdeps/x86_64/multiarch/wcslen-sse4_1.S      |  10 +-
 sysdeps/x86_64/multiarch/wcsncmp-avx2-rtm.S   |   2 -
 sysdeps/x86_64/multiarch/wcsncmp-avx2.S       |   3 +-
 sysdeps/x86_64/multiarch/wcsncmp-evex.S       |   1 -
 sysdeps/x86_64/multiarch/wcsncmp-generic.c    |   9 +-
 sysdeps/x86_64/multiarch/wcsnlen-avx2.S       |   6 +-
 sysdeps/x86_64/multiarch/wcsnlen-evex.S       |   6 +-
 sysdeps/x86_64/multiarch/wcsnlen-generic.c    |  13 +-
 sysdeps/x86_64/multiarch/wcsnlen-sse4_1.S     |   7 +-
 sysdeps/x86_64/multiarch/wcsrchr-avx2.S       |   7 +-
 sysdeps/x86_64/multiarch/wcsrchr-evex.S       |   6 +-
 sysdeps/x86_64/multiarch/wcsrchr-sse2.S       |   7 +-
 sysdeps/x86_64/strcasecmp_l.S                 |  32 +-
 sysdeps/x86_64/strchr-isa-default-impl.h      |  28 +
 sysdeps/x86_64/strchr.S                       |  12 +-
 sysdeps/x86_64/strchrnul.S                    |  13 +-
 sysdeps/x86_64/strcmp.S                       |  13 +-
 sysdeps/x86_64/strlen.S                       |   9 +-
 sysdeps/x86_64/strncase_l.S                   |  32 +-
 sysdeps/x86_64/strncmp.S                      |  29 +-
 sysdeps/x86_64/strnlen.S                      |  31 +-
 sysdeps/x86_64/strrchr.S                      |  10 +-
 sysdeps/x86_64/wcschr.S                       |  13 +-
 sysdeps/x86_64/wcscmp.S                       |   9 +-
 sysdeps/x86_64/wcslen.S                       |  19 +-
 sysdeps/x86_64/wcsncmp-generic.c              |  29 +
 sysdeps/x86_64/wcsncmp.S                      |  40 ++
 sysdeps/x86_64/wcsnlen-generic.c              |  29 +
 sysdeps/x86_64/wcsnlen.S                      |  49 ++
 sysdeps/x86_64/wcsrchr.S                      |  11 +-
 88 files changed, 1157 insertions(+), 618 deletions(-)
 create mode 100644 sysdeps/x86_64/strchr-isa-default-impl.h
 create mode 100644 sysdeps/x86_64/wcsncmp-generic.c
 create mode 100644 sysdeps/x86_64/wcsncmp.S
 create mode 100644 sysdeps/x86_64/wcsnlen-generic.c
 create mode 100644 sysdeps/x86_64/wcsnlen.S
diff mbox series

Patch

diff --git a/sysdeps/x86/isa-level.h b/sysdeps/x86/isa-level.h
index 77f9e2c0c3..3c4480aba7 100644
--- a/sysdeps/x86/isa-level.h
+++ b/sysdeps/x86/isa-level.h
@@ -84,6 +84,7 @@ 
 
 /* ISA level >= 2 guaranteed includes.  */
 #define SSE4_2_X86_ISA_LEVEL 2
+#define SSE4_1_X86_ISA_LEVEL 2
 #define SSSE3_X86_ISA_LEVEL 2
 
 
@@ -101,9 +102,18 @@ 
    when ISA level < 3.  */
 #define Prefer_No_VZEROUPPER_X86_ISA_LEVEL 3
 
+/* NB: This feature is disable when ISA level >= 3.  All CPUs with
+   this feature don't run on glibc built with ISA level >= 3.  */
+#define Slow_SSE42_X86_ISA_LEVEL 3
+
 /* Feature(s) enabled when ISA level >= 2.  */
 #define Fast_Unaligned_Load_X86_ISA_LEVEL 2
 
+/* NB: This feature is disable when ISA level >= 2, which was enabled
+   for the early Atom CPUs.  */
+#define Slow_BSF_X86_ISA_LEVEL 2
+
+
 /* Both X86_ISA_CPU_FEATURE_USABLE_P and X86_ISA_CPU_FEATURES_ARCH_P
    macros are wrappers for the respective CPU_FEATURE{S}_{USABLE|ARCH}_P
    runtime checks.  They differ in two ways.
diff --git a/sysdeps/x86_64/Makefile b/sysdeps/x86_64/Makefile
index e597a4855f..341ee69a35 100644
--- a/sysdeps/x86_64/Makefile
+++ b/sysdeps/x86_64/Makefile
@@ -197,6 +197,12 @@  gen-as-const-headers += tlsdesc.sym rtld-offsets.sym
 endif
 
 ifeq ($(subdir),wcsmbs)
+
+sysdep_routines += \
+  wcsncmp-generic \
+  wcsnlen-generic \
+# sysdep_routines
+
 tests += \
   tst-rsi-wcslen
 endif
diff --git a/sysdeps/x86_64/memrchr.S b/sysdeps/x86_64/memrchr.S
index 385e2c5668..d39b1aa0e2 100644
--- a/sysdeps/x86_64/memrchr.S
+++ b/sysdeps/x86_64/memrchr.S
@@ -1,4 +1,4 @@ 
-/* fast SSE2 memrchr with 64 byte loop and pmaxub instruction using
+/* memrchr dispatch for RTLD and non-multiarch build
 
    Copyright (C) 2011-2022 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
@@ -18,5 +18,11 @@ 
    <https://www.gnu.org/licenses/>.  */
 
 #define MEMRCHR	__memrchr
-#include "multiarch/memrchr-sse2.S"
+
+#define DEFAULT_IMPL_V1	"multiarch/memrchr-sse2.S"
+#define DEFAULT_IMPL_V3	"multiarch/memrchr-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/memrchr-evex.S"
+
+#include "isa-default-impl.h"
+
 weak_alias (__memrchr, memrchr)
diff --git a/sysdeps/x86_64/multiarch/Makefile b/sysdeps/x86_64/multiarch/Makefile
index d6b62af850..ba29a65716 100644
--- a/sysdeps/x86_64/multiarch/Makefile
+++ b/sysdeps/x86_64/multiarch/Makefile
@@ -144,11 +144,9 @@  sysdep_routines += \
   wcslen-sse4_1 \
   wcsncmp-avx2 \
   wcsncmp-avx2-rtm \
-  wcsncmp-generic \
   wcsncmp-evex \
   wcsnlen-avx2 \
   wcsnlen-avx2-rtm \
-  wcsnlen-generic \
   wcsnlen-evex \
   wcsnlen-evex512 \
   wcsnlen-sse4_1 \
diff --git a/sysdeps/x86_64/multiarch/ifunc-avx2.h b/sysdeps/x86_64/multiarch/ifunc-avx2.h
index 1d9cdfcfec..a57a9952f3 100644
--- a/sysdeps/x86_64/multiarch/ifunc-avx2.h
+++ b/sysdeps/x86_64/multiarch/ifunc-avx2.h
@@ -23,28 +23,32 @@ 
 # define GENERIC sse2
 #endif
 
-extern __typeof (REDIRECT_NAME) OPTIMIZE (GENERIC) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
-extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
+extern __typeof (REDIRECT_NAME) OPTIMIZE (GENERIC) attribute_hidden;
 
 static inline void *
 IFUNC_SELECTOR (void)
 {
-  const struct cpu_features* cpu_features = __get_cpu_features ();
+  const struct cpu_features *cpu_features = __get_cpu_features ();
 
-  if (CPU_FEATURE_USABLE_P (cpu_features, AVX2)
-      && CPU_FEATURE_USABLE_P (cpu_features, BMI2)
-      && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
+  if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX2)
+      && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, BMI2)
+      && X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
+				      AVX_Fast_Unaligned_Load, ))
     {
-      if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
-	  && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
+      if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
+	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
 	return OPTIMIZE (evex);
 
       if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
 	return OPTIMIZE (avx2_rtm);
 
-      if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
+      if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
+				       Prefer_No_VZEROUPPER, !))
 	return OPTIMIZE (avx2);
     }
 
diff --git a/sysdeps/x86_64/multiarch/ifunc-impl-list.c b/sysdeps/x86_64/multiarch/ifunc-impl-list.c
index 2c96cb62d2..3b1df9b73c 100644
--- a/sysdeps/x86_64/multiarch/ifunc-impl-list.c
+++ b/sysdeps/x86_64/multiarch/ifunc-impl-list.c
@@ -205,19 +205,22 @@  __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 
   /* Support sysdeps/x86_64/multiarch/memrchr.c.  */
   IFUNC_IMPL (i, name, memrchr,
-	      IFUNC_IMPL_ADD (array, i, memrchr,
-			      CPU_FEATURE_USABLE (AVX2),
-			      __memrchr_avx2)
-	      IFUNC_IMPL_ADD (array, i, memrchr,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __memrchr_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, memrchr,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)),
-			      __memrchr_evex)
-
-	      IFUNC_IMPL_ADD (array, i, memrchr, 1, __memrchr_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, memrchr,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)),
+				     __memrchr_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, memrchr,
+				     CPU_FEATURE_USABLE (AVX2),
+				     __memrchr_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, memrchr,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __memrchr_avx2_rtm)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, memrchr,
+				     1,
+				     __memrchr_sse2))
 
 #ifdef SHARED
   /* Support sysdeps/x86_64/multiarch/memset_chk.c.  */
@@ -346,49 +349,57 @@  __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 
   /* Support sysdeps/x86_64/multiarch/strlen.c.  */
   IFUNC_IMPL (i, name, strlen,
-	      IFUNC_IMPL_ADD (array, i, strlen,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __strlen_avx2)
-	      IFUNC_IMPL_ADD (array, i, strlen,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __strlen_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, strlen,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __strlen_evex)
-	      IFUNC_IMPL_ADD (array, i, strlen,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __strlen_evex512)
-	      IFUNC_IMPL_ADD (array, i, strlen, 1, __strlen_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strlen,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __strlen_evex)
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strlen,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __strlen_evex512)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strlen,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __strlen_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strlen,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __strlen_avx2_rtm)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strlen,
+				     1,
+				     __strlen_sse2))
 
   /* Support sysdeps/x86_64/multiarch/strnlen.c.  */
   IFUNC_IMPL (i, name, strnlen,
-	      IFUNC_IMPL_ADD (array, i, strnlen,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __strnlen_avx2)
-	      IFUNC_IMPL_ADD (array, i, strnlen,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __strnlen_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, strnlen,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __strnlen_evex)
-	      IFUNC_IMPL_ADD (array, i, strnlen,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __strnlen_evex512)
-	      IFUNC_IMPL_ADD (array, i, strnlen, 1, __strnlen_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strnlen,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __strnlen_evex)
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strnlen,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __strnlen_evex512)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strnlen,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __strnlen_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strnlen,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __strnlen_avx2_rtm)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strnlen,
+				     1,
+				     __strnlen_sse2))
 
   /* Support sysdeps/x86_64/multiarch/stpncpy.c.  */
   IFUNC_IMPL (i, name, stpncpy,
@@ -422,40 +433,47 @@  __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 
   /* Support sysdeps/x86_64/multiarch/strcasecmp_l.c.  */
   IFUNC_IMPL (i, name, strcasecmp,
-	      IFUNC_IMPL_ADD (array, i, strcasecmp,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)),
-			      __strcasecmp_evex)
-	      IFUNC_IMPL_ADD (array, i, strcasecmp,
-			      CPU_FEATURE_USABLE (AVX2),
-			      __strcasecmp_avx2)
-	      IFUNC_IMPL_ADD (array, i, strcasecmp,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __strcasecmp_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, strcasecmp,
-			      CPU_FEATURE_USABLE (SSE4_2),
-			      __strcasecmp_sse42)
-	      IFUNC_IMPL_ADD (array, i, strcasecmp, 1, __strcasecmp_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strcasecmp,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)),
+				     __strcasecmp_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strcasecmp,
+				     CPU_FEATURE_USABLE (AVX2),
+				     __strcasecmp_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strcasecmp,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __strcasecmp_avx2_rtm)
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strcasecmp,
+				     CPU_FEATURE_USABLE (SSE4_2),
+				     __strcasecmp_sse42)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strcasecmp,
+				     1,
+				     __strcasecmp_sse2))
 
   /* Support sysdeps/x86_64/multiarch/strcasecmp_l.c.  */
   IFUNC_IMPL (i, name, strcasecmp_l,
-	      IFUNC_IMPL_ADD (array, i, strcasecmp,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)),
-			      __strcasecmp_l_evex)
-	      IFUNC_IMPL_ADD (array, i, strcasecmp,
-			      CPU_FEATURE_USABLE (AVX2),
-			      __strcasecmp_l_avx2)
-	      IFUNC_IMPL_ADD (array, i, strcasecmp,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __strcasecmp_l_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, strcasecmp_l,
-			      CPU_FEATURE_USABLE (SSE4_2),
-			      __strcasecmp_l_sse42)
-	      IFUNC_IMPL_ADD (array, i, strcasecmp_l, 1,
-			      __strcasecmp_l_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strcasecmp,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)),
+				     __strcasecmp_l_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strcasecmp,
+				     CPU_FEATURE_USABLE (AVX2),
+				     __strcasecmp_l_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strcasecmp,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __strcasecmp_l_avx2_rtm)
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strcasecmp_l,
+				     CPU_FEATURE_USABLE (SSE4_2),
+				     __strcasecmp_l_sse42)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strcasecmp_l,
+				     1,
+				     __strcasecmp_l_sse2))
 
   /* Support sysdeps/x86_64/multiarch/strcat.c.  */
   IFUNC_IMPL (i, name, strcat,
@@ -474,74 +492,95 @@  __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 
   /* Support sysdeps/x86_64/multiarch/strchr.c.  */
   IFUNC_IMPL (i, name, strchr,
-	      IFUNC_IMPL_ADD (array, i, strchr,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __strchr_avx2)
-	      IFUNC_IMPL_ADD (array, i, strchr,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __strchr_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, strchr,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __strchr_evex)
-	      IFUNC_IMPL_ADD (array, i, strchr, 1, __strchr_sse2_no_bsf)
-	      IFUNC_IMPL_ADD (array, i, strchr, 1, __strchr_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strchr,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __strchr_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strchr,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __strchr_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strchr,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __strchr_avx2_rtm)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strchr,
+				     1,
+				     __strchr_sse2)
+	      X86_IFUNC_IMPL_ADD_V1 (array, i, strchr,
+				     1,
+				     __strchr_sse2_no_bsf))
 
   /* Support sysdeps/x86_64/multiarch/strchrnul.c.  */
   IFUNC_IMPL (i, name, strchrnul,
-	      IFUNC_IMPL_ADD (array, i, strchrnul,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __strchrnul_avx2)
-	      IFUNC_IMPL_ADD (array, i, strchrnul,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __strchrnul_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, strchrnul,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __strchrnul_evex)
-	      IFUNC_IMPL_ADD (array, i, strchrnul, 1, __strchrnul_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strchrnul,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __strchrnul_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strchrnul,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __strchrnul_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strchrnul,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __strchrnul_avx2_rtm)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strchrnul,
+				     1,
+				     __strchrnul_sse2))
 
   /* Support sysdeps/x86_64/multiarch/strrchr.c.  */
   IFUNC_IMPL (i, name, strrchr,
-	      IFUNC_IMPL_ADD (array, i, strrchr,
-			      CPU_FEATURE_USABLE (AVX2),
-			      __strrchr_avx2)
-	      IFUNC_IMPL_ADD (array, i, strrchr,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __strrchr_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, strrchr,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)),
-			      __strrchr_evex)
-	      IFUNC_IMPL_ADD (array, i, strrchr, 1, __strrchr_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strrchr,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)),
+				     __strrchr_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strrchr,
+				     CPU_FEATURE_USABLE (AVX2),
+				     __strrchr_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strrchr,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __strrchr_avx2_rtm)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strrchr,
+				     1,
+				     __strrchr_sse2))
 
   /* Support sysdeps/x86_64/multiarch/strcmp.c.  */
   IFUNC_IMPL (i, name, strcmp,
-	      IFUNC_IMPL_ADD (array, i, strcmp,
-			      CPU_FEATURE_USABLE (AVX2),
-			      __strcmp_avx2)
-	      IFUNC_IMPL_ADD (array, i, strcmp,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __strcmp_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, strcmp,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __strcmp_evex)
-	      IFUNC_IMPL_ADD (array, i, strcmp, CPU_FEATURE_USABLE (SSE4_2),
-			      __strcmp_sse42)
-	      IFUNC_IMPL_ADD (array, i, strcmp, 1, __strcmp_sse2_unaligned)
-	      IFUNC_IMPL_ADD (array, i, strcmp, 1, __strcmp_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strcmp,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __strcmp_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strcmp,
+				     CPU_FEATURE_USABLE (AVX2),
+				     __strcmp_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strcmp,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __strcmp_avx2_rtm)
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strcmp,
+                                 CPU_FEATURE_USABLE (SSE4_2),
+                                 __strcmp_sse42)
+	      /* ISA V2 wrapper for SSE2 implementations because the SSE2
+	         implementations are also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strcmp,
+				     1,
+				     __strcmp_sse2_unaligned)
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strcmp,
+				     1,
+				     __strcmp_sse2))
 
   /* Support sysdeps/x86_64/multiarch/strcpy.c.  */
   IFUNC_IMPL (i, name, strcpy,
@@ -568,41 +607,47 @@  __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 
   /* Support sysdeps/x86_64/multiarch/strncase_l.c.  */
   IFUNC_IMPL (i, name, strncasecmp,
-	      IFUNC_IMPL_ADD (array, i, strncasecmp,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)),
-			      __strncasecmp_evex)
-	      IFUNC_IMPL_ADD (array, i, strncasecmp,
-			      CPU_FEATURE_USABLE (AVX2),
-			      __strncasecmp_avx2)
-	      IFUNC_IMPL_ADD (array, i, strncasecmp,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __strncasecmp_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, strncasecmp,
-			      CPU_FEATURE_USABLE (SSE4_2),
-			      __strncasecmp_sse42)
-	      IFUNC_IMPL_ADD (array, i, strncasecmp, 1,
-			      __strncasecmp_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strncasecmp,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)),
+				     __strncasecmp_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strncasecmp,
+				     CPU_FEATURE_USABLE (AVX2),
+				     __strncasecmp_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strncasecmp,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __strncasecmp_avx2_rtm)
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strncasecmp,
+				     CPU_FEATURE_USABLE (SSE4_2),
+				     __strncasecmp_sse42)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strncasecmp,
+				     1,
+				     __strncasecmp_sse2))
 
   /* Support sysdeps/x86_64/multiarch/strncase_l.c.  */
   IFUNC_IMPL (i, name, strncasecmp_l,
-	      IFUNC_IMPL_ADD (array, i, strncasecmp,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)),
-			      __strncasecmp_l_evex)
-	      IFUNC_IMPL_ADD (array, i, strncasecmp,
-			      CPU_FEATURE_USABLE (AVX2),
-			      __strncasecmp_l_avx2)
-	      IFUNC_IMPL_ADD (array, i, strncasecmp,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __strncasecmp_l_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, strncasecmp_l,
-			      CPU_FEATURE_USABLE (SSE4_2),
-			      __strncasecmp_l_sse42)
-	      IFUNC_IMPL_ADD (array, i, strncasecmp_l, 1,
-			      __strncasecmp_l_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strncasecmp,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)),
+				     __strncasecmp_l_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strncasecmp,
+				     CPU_FEATURE_USABLE (AVX2),
+				     __strncasecmp_l_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strncasecmp,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __strncasecmp_l_avx2_rtm)
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strncasecmp_l,
+				     CPU_FEATURE_USABLE (SSE4_2),
+				     __strncasecmp_l_sse42)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strncasecmp_l,
+				     1,
+				     __strncasecmp_l_sse2))
 
   /* Support sysdeps/x86_64/multiarch/strncat.c.  */
   IFUNC_IMPL (i, name, strncat,
@@ -664,69 +709,85 @@  __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 
   /* Support sysdeps/x86_64/multiarch/wcschr.c.  */
   IFUNC_IMPL (i, name, wcschr,
-	      IFUNC_IMPL_ADD (array, i, wcschr,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __wcschr_avx2)
-	      IFUNC_IMPL_ADD (array, i, wcschr,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __wcschr_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, wcschr,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __wcschr_evex)
-	      IFUNC_IMPL_ADD (array, i, wcschr, 1, __wcschr_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, wcschr,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __wcschr_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, wcschr,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __wcschr_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, wcschr,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __wcschr_avx2_rtm)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, wcschr,
+				     1,
+				     __wcschr_sse2))
 
   /* Support sysdeps/x86_64/multiarch/wcsrchr.c.  */
   IFUNC_IMPL (i, name, wcsrchr,
-	      IFUNC_IMPL_ADD (array, i, wcsrchr,
-			      CPU_FEATURE_USABLE (AVX2),
-			      __wcsrchr_avx2)
-	      IFUNC_IMPL_ADD (array, i, wcsrchr,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __wcsrchr_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, wcsrchr,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __wcsrchr_evex)
-	      IFUNC_IMPL_ADD (array, i, wcsrchr, 1, __wcsrchr_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, wcsrchr,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __wcsrchr_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, wcsrchr,
+				     CPU_FEATURE_USABLE (AVX2),
+				     __wcsrchr_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, wcsrchr,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __wcsrchr_avx2_rtm)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, wcsrchr,
+				     1,
+				     __wcsrchr_sse2))
 
   /* Support sysdeps/x86_64/multiarch/wcscmp.c.  */
   IFUNC_IMPL (i, name, wcscmp,
-	      IFUNC_IMPL_ADD (array, i, wcscmp,
-			      CPU_FEATURE_USABLE (AVX2),
-			      __wcscmp_avx2)
-	      IFUNC_IMPL_ADD (array, i, wcscmp,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __wcscmp_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, wcscmp,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __wcscmp_evex)
-	      IFUNC_IMPL_ADD (array, i, wcscmp, 1, __wcscmp_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, wcscmp,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __wcscmp_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, wcscmp,
+				     CPU_FEATURE_USABLE (AVX2),
+				     __wcscmp_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, wcscmp,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __wcscmp_avx2_rtm)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, wcscmp,
+				     1,
+				     __wcscmp_sse2))
 
   /* Support sysdeps/x86_64/multiarch/wcsncmp.c.  */
   IFUNC_IMPL (i, name, wcsncmp,
-	      IFUNC_IMPL_ADD (array, i, wcsncmp,
-			      CPU_FEATURE_USABLE (AVX2),
-			      __wcsncmp_avx2)
-	      IFUNC_IMPL_ADD (array, i, wcsncmp,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __wcsncmp_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, wcsncmp,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __wcsncmp_evex)
-	      IFUNC_IMPL_ADD (array, i, wcsncmp, 1, __wcsncmp_generic))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, wcsncmp,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __wcsncmp_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, wcsncmp,
+				     CPU_FEATURE_USABLE (AVX2),
+				     __wcsncmp_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, wcsncmp,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __wcsncmp_avx2_rtm)
+	      /* ISA V2 wrapper for GENERIC implementation because the
+	         GENERIC implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, wcsncmp,
+				     1,
+				     __wcsncmp_generic))
 
   /* Support sysdeps/x86_64/multiarch/wcscpy.c.  */
   IFUNC_IMPL (i, name, wcscpy,
@@ -736,55 +797,59 @@  __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 
   /* Support sysdeps/x86_64/multiarch/wcslen.c.  */
   IFUNC_IMPL (i, name, wcslen,
-	      IFUNC_IMPL_ADD (array, i, wcslen,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __wcslen_avx2)
-	      IFUNC_IMPL_ADD (array, i, wcslen,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __wcslen_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, wcslen,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __wcslen_evex)
-	      IFUNC_IMPL_ADD (array, i, wcslen,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __wcslen_evex512)
-	      IFUNC_IMPL_ADD (array, i, wcslen,
-			      CPU_FEATURE_USABLE (SSE4_1),
-			      __wcslen_sse4_1)
-	      IFUNC_IMPL_ADD (array, i, wcslen, 1, __wcslen_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, wcslen,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __wcslen_evex)
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, wcslen,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __wcslen_evex512)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, wcslen,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __wcslen_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, wcslen,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __wcslen_avx2_rtm)
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, wcslen,
+				     CPU_FEATURE_USABLE (SSE4_1),
+				     __wcslen_sse4_1)
+	      X86_IFUNC_IMPL_ADD_V1 (array, i, wcslen,
+				     1,
+				     __wcslen_sse2))
 
   /* Support sysdeps/x86_64/multiarch/wcsnlen.c.  */
   IFUNC_IMPL (i, name, wcsnlen,
-	      IFUNC_IMPL_ADD (array, i, wcsnlen,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __wcsnlen_avx2)
-	      IFUNC_IMPL_ADD (array, i, wcsnlen,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (BMI2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __wcsnlen_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, wcsnlen,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __wcsnlen_evex)
-	      IFUNC_IMPL_ADD (array, i, wcsnlen,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)
-			       && CPU_FEATURE_USABLE (BMI2)),
-			      __wcsnlen_evex512)
-	      IFUNC_IMPL_ADD (array, i, wcsnlen,
-			      CPU_FEATURE_USABLE (SSE4_1),
-			      __wcsnlen_sse4_1)
-	      IFUNC_IMPL_ADD (array, i, wcsnlen, 1, __wcsnlen_generic))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, wcsnlen,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __wcsnlen_evex)
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, wcsnlen,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __wcsnlen_evex512)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, wcsnlen,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)),
+				     __wcsnlen_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, wcsnlen,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (BMI2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __wcsnlen_avx2_rtm)
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, wcsnlen,
+				     CPU_FEATURE_USABLE (SSE4_1),
+				     __wcsnlen_sse4_1)
+	      X86_IFUNC_IMPL_ADD_V1 (array, i, wcsnlen,
+				     1,
+				     __wcsnlen_generic))
 
   /* Support sysdeps/x86_64/multiarch/wmemchr.c.  */
   IFUNC_IMPL (i, name, wmemchr,
@@ -1050,20 +1115,25 @@  __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 
   /* Support sysdeps/x86_64/multiarch/strncmp.c.  */
   IFUNC_IMPL (i, name, strncmp,
-	      IFUNC_IMPL_ADD (array, i, strncmp,
-			      CPU_FEATURE_USABLE (AVX2),
-			      __strncmp_avx2)
-	      IFUNC_IMPL_ADD (array, i, strncmp,
-			      (CPU_FEATURE_USABLE (AVX2)
-			       && CPU_FEATURE_USABLE (RTM)),
-			      __strncmp_avx2_rtm)
-	      IFUNC_IMPL_ADD (array, i, strncmp,
-			      (CPU_FEATURE_USABLE (AVX512VL)
-			       && CPU_FEATURE_USABLE (AVX512BW)),
-			      __strncmp_evex)
-	      IFUNC_IMPL_ADD (array, i, strncmp, CPU_FEATURE_USABLE (SSE4_2),
-			      __strncmp_sse42)
-	      IFUNC_IMPL_ADD (array, i, strncmp, 1, __strncmp_sse2))
+	      X86_IFUNC_IMPL_ADD_V4 (array, i, strncmp,
+				     (CPU_FEATURE_USABLE (AVX512VL)
+				      && CPU_FEATURE_USABLE (AVX512BW)),
+				     __strncmp_evex)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strncmp,
+				     CPU_FEATURE_USABLE (AVX2),
+				     __strncmp_avx2)
+	      X86_IFUNC_IMPL_ADD_V3 (array, i, strncmp,
+				     (CPU_FEATURE_USABLE (AVX2)
+				      && CPU_FEATURE_USABLE (RTM)),
+				     __strncmp_avx2_rtm)
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strncmp,
+				     CPU_FEATURE_USABLE (SSE4_2),
+				     __strncmp_sse42)
+	      /* ISA V2 wrapper for SSE2 implementation because the SSE2
+	         implementation is also used at ISA level 2.  */
+	      X86_IFUNC_IMPL_ADD_V2 (array, i, strncmp,
+				     1,
+				     __strncmp_sse2))
 
 #ifdef SHARED
   /* Support sysdeps/x86_64/multiarch/wmemset_chk.c.  */
diff --git a/sysdeps/x86_64/multiarch/ifunc-strcasecmp.h b/sysdeps/x86_64/multiarch/ifunc-strcasecmp.h
index 296d32071b..68646ef199 100644
--- a/sysdeps/x86_64/multiarch/ifunc-strcasecmp.h
+++ b/sysdeps/x86_64/multiarch/ifunc-strcasecmp.h
@@ -19,32 +19,39 @@ 
 
 #include <init-arch.h>
 
-extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
-extern __typeof (REDIRECT_NAME) OPTIMIZE (sse42) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
-extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse42) attribute_hidden;
+
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
 
 static inline void *
 IFUNC_SELECTOR (void)
 {
-  const struct cpu_features* cpu_features = __get_cpu_features ();
+  const struct cpu_features *cpu_features = __get_cpu_features ();
 
-  if (CPU_FEATURE_USABLE_P (cpu_features, AVX2)
-      && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
+  if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX2)
+      && X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
+				      AVX_Fast_Unaligned_Load, ))
     {
-      if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
-          && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
-        return OPTIMIZE (evex);
+      if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
+	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
+	return OPTIMIZE (evex);
 
       if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
-        return OPTIMIZE (avx2_rtm);
+	return OPTIMIZE (avx2_rtm);
 
-      if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
-        return OPTIMIZE (avx2);
+      if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
+				       Prefer_No_VZEROUPPER, !))
+	return OPTIMIZE (avx2);
     }
 
-  if (CPU_FEATURE_USABLE_P (cpu_features, SSE4_2)
+  if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, SSE4_2)
+      /* Keep this as a runtime check as its not guaranteed at ISA
+         level 2.  */
       && !CPU_FEATURES_ARCH_P (cpu_features, Slow_SSE4_2))
     return OPTIMIZE (sse42);
 
diff --git a/sysdeps/x86_64/multiarch/ifunc-wcslen.h b/sysdeps/x86_64/multiarch/ifunc-wcslen.h
index 88c1c502af..064722c2bd 100644
--- a/sysdeps/x86_64/multiarch/ifunc-wcslen.h
+++ b/sysdeps/x86_64/multiarch/ifunc-wcslen.h
@@ -23,33 +23,38 @@ 
 # define GENERIC sse2
 #endif
 
-extern __typeof (REDIRECT_NAME) OPTIMIZE (GENERIC) attribute_hidden;
-extern __typeof (REDIRECT_NAME) OPTIMIZE (sse4_1) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
-extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse4_1) attribute_hidden;
+
+extern __typeof (REDIRECT_NAME) OPTIMIZE (GENERIC) attribute_hidden;
 
 static inline void *
 IFUNC_SELECTOR (void)
 {
-  const struct cpu_features* cpu_features = __get_cpu_features ();
+  const struct cpu_features *cpu_features = __get_cpu_features ();
 
-  if (CPU_FEATURE_USABLE_P (cpu_features, AVX2)
-      && CPU_FEATURE_USABLE_P (cpu_features, BMI2)
-      && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
+  if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX2)
+      && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, BMI2)
+      && X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
+				      AVX_Fast_Unaligned_Load, ))
     {
-      if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
-	  && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
+      if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
+	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
 	return OPTIMIZE (evex);
 
       if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
 	return OPTIMIZE (avx2_rtm);
 
-      if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
+      if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
+				       Prefer_No_VZEROUPPER, !))
 	return OPTIMIZE (avx2);
     }
 
-  if (CPU_FEATURE_USABLE_P (cpu_features, SSE4_1))
+  if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, SSE4_1))
     return OPTIMIZE (sse4_1);
 
   return OPTIMIZE (GENERIC);
diff --git a/sysdeps/x86_64/multiarch/memrchr-avx2.S b/sysdeps/x86_64/multiarch/memrchr-avx2.S
index f300d7daf4..d1457ab60c 100644
--- a/sysdeps/x86_64/multiarch/memrchr-avx2.S
+++ b/sysdeps/x86_64/multiarch/memrchr-avx2.S
@@ -16,7 +16,9 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (3)
 
 # include <sysdep.h>
 
diff --git a/sysdeps/x86_64/multiarch/memrchr-evex.S b/sysdeps/x86_64/multiarch/memrchr-evex.S
index 91329b18dc..ea3a0a0a60 100644
--- a/sysdeps/x86_64/multiarch/memrchr-evex.S
+++ b/sysdeps/x86_64/multiarch/memrchr-evex.S
@@ -16,7 +16,9 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (4)
 
 # include <sysdep.h>
 # include "evex256-vecs.h"
diff --git a/sysdeps/x86_64/multiarch/memrchr-sse2.S b/sysdeps/x86_64/multiarch/memrchr-sse2.S
index d92a4022dc..4cc8b9e3b0 100644
--- a/sysdeps/x86_64/multiarch/memrchr-sse2.S
+++ b/sysdeps/x86_64/multiarch/memrchr-sse2.S
@@ -16,22 +16,26 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+/* MINIMUM_X86_ISA_LEVEL <= 2 because there is no V2 implementation
+   so we need this to build for ISA V2 builds. */
+#if ISA_SHOULD_BUILD (2)
+
 # ifndef MEMRCHR
 #  define MEMRCHR __memrchr_sse2
 # endif
-#endif
 
-#include <sysdep.h>
-#define VEC_SIZE			16
-#define PAGE_SIZE			4096
+# include <sysdep.h>
+# define VEC_SIZE			16
+# define PAGE_SIZE			4096
 
 	.text
 ENTRY_P2ALIGN(MEMRCHR, 6)
-#ifdef __ILP32__
+# ifdef __ILP32__
 	/* Clear upper bits.  */
 	mov	%RDX_LP, %RDX_LP
-#endif
+# endif
 	movd	%esi, %xmm0
 
 	/* Get end pointer.  */
@@ -352,3 +356,4 @@  L(zero_3):
 	ret
 	/* 2-bytes from next cache line.  */
 END(MEMRCHR)
+#endif
diff --git a/sysdeps/x86_64/multiarch/strcasecmp_l-avx2-rtm.S b/sysdeps/x86_64/multiarch/strcasecmp_l-avx2-rtm.S
index 09957fc3c5..d408751f4c 100644
--- a/sysdeps/x86_64/multiarch/strcasecmp_l-avx2-rtm.S
+++ b/sysdeps/x86_64/multiarch/strcasecmp_l-avx2-rtm.S
@@ -1,15 +1,2 @@ 
-#ifndef STRCMP
-# define STRCMP	__strcasecmp_l_avx2_rtm
-#endif
-
-#define _GLABEL(x)	x ## _rtm
-#define GLABEL(x)	_GLABEL(x)
-
-#define ZERO_UPPER_VEC_REGISTERS_RETURN	\
-	ZERO_UPPER_VEC_REGISTERS_RETURN_XTEST
-
-#define VZEROUPPER_RETURN	jmp L(return_vzeroupper)
-
-#define SECTION(p)	p##.avx.rtm
-
-#include "strcasecmp_l-avx2.S"
+#define USE_AS_STRCASECMP_L
+#include "strcmp-avx2-rtm.S"
diff --git a/sysdeps/x86_64/multiarch/strcasecmp_l-avx2.S b/sysdeps/x86_64/multiarch/strcasecmp_l-avx2.S
index e2762f2a22..167f866014 100644
--- a/sysdeps/x86_64/multiarch/strcasecmp_l-avx2.S
+++ b/sysdeps/x86_64/multiarch/strcasecmp_l-avx2.S
@@ -16,8 +16,5 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#ifndef STRCMP
-# define STRCMP	__strcasecmp_l_avx2
-#endif
 #define USE_AS_STRCASECMP_L
 #include "strcmp-avx2.S"
diff --git a/sysdeps/x86_64/multiarch/strcasecmp_l-evex.S b/sysdeps/x86_64/multiarch/strcasecmp_l-evex.S
index 58642db748..012a084930 100644
--- a/sysdeps/x86_64/multiarch/strcasecmp_l-evex.S
+++ b/sysdeps/x86_64/multiarch/strcasecmp_l-evex.S
@@ -16,8 +16,5 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#ifndef STRCMP
-# define STRCMP	__strcasecmp_l_evex
-#endif
 #define USE_AS_STRCASECMP_L
 #include "strcmp-evex.S"
diff --git a/sysdeps/x86_64/multiarch/strcasecmp_l-sse2.S b/sysdeps/x86_64/multiarch/strcasecmp_l-sse2.S
index a2b5741399..6ffd09b513 100644
--- a/sysdeps/x86_64/multiarch/strcasecmp_l-sse2.S
+++ b/sysdeps/x86_64/multiarch/strcasecmp_l-sse2.S
@@ -17,4 +17,5 @@ 
    <https://www.gnu.org/licenses/>.  */
 
 #define USE_AS_STRCASECMP_L
+
 #include "strcmp-sse2.S"
diff --git a/sysdeps/x86_64/multiarch/strchr-avx2.S b/sysdeps/x86_64/multiarch/strchr-avx2.S
index 1a916cc951..425a40b8de 100644
--- a/sysdeps/x86_64/multiarch/strchr-avx2.S
+++ b/sysdeps/x86_64/multiarch/strchr-avx2.S
@@ -16,7 +16,9 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (3)
 
 # include <sysdep.h>
 
diff --git a/sysdeps/x86_64/multiarch/strchr-evex.S b/sysdeps/x86_64/multiarch/strchr-evex.S
index ec739fb8f9..a1c15c4419 100644
--- a/sysdeps/x86_64/multiarch/strchr-evex.S
+++ b/sysdeps/x86_64/multiarch/strchr-evex.S
@@ -16,7 +16,9 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (4)
 
 # include <sysdep.h>
 
diff --git a/sysdeps/x86_64/multiarch/strchr-sse2-no-bsf.S b/sysdeps/x86_64/multiarch/strchr-sse2-no-bsf.S
index 93e6f62d7f..bb092e3f61 100644
--- a/sysdeps/x86_64/multiarch/strchr-sse2-no-bsf.S
+++ b/sysdeps/x86_64/multiarch/strchr-sse2-no-bsf.S
@@ -16,7 +16,11 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+/* NB: atom builds with ISA level == 1 so no reason to hold onto this
+   at ISA level >= 2.  */
+#if ISA_SHOULD_BUILD (1)
 
 # include <sysdep.h>
 # include "asm-syntax.h"
diff --git a/sysdeps/x86_64/multiarch/strchr-sse2.S b/sysdeps/x86_64/multiarch/strchr-sse2.S
index f7767ca543..7a182f0c3b 100644
--- a/sysdeps/x86_64/multiarch/strchr-sse2.S
+++ b/sysdeps/x86_64/multiarch/strchr-sse2.S
@@ -16,7 +16,12 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc) || defined STRCHR
+#include <isa-level.h>
+
+/* MINIMUM_X86_ISA_LEVEL <= 2 because there is no V2 implementation
+   so we need this to build for ISA V2 builds. */
+#if ISA_SHOULD_BUILD (2)
+
 # ifndef STRCHR
 #  define STRCHR __strchr_sse2
 # endif
diff --git a/sysdeps/x86_64/multiarch/strchr.c b/sysdeps/x86_64/multiarch/strchr.c
index de737580eb..ce7441c532 100644
--- a/sysdeps/x86_64/multiarch/strchr.c
+++ b/sysdeps/x86_64/multiarch/strchr.c
@@ -26,36 +26,40 @@ 
 # define SYMBOL_NAME strchr
 # include <init-arch.h>
 
-extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
-extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_no_bsf) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
-extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_no_bsf) attribute_hidden;
 
 static inline void *
 IFUNC_SELECTOR (void)
 {
-  const struct cpu_features* cpu_features = __get_cpu_features ();
+  const struct cpu_features *cpu_features = __get_cpu_features ();
 
-  if (CPU_FEATURE_USABLE_P (cpu_features, AVX2)
-      && CPU_FEATURE_USABLE_P (cpu_features, BMI2)
-      && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
+  if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX2)
+      && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, BMI2)
+      && X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
+				      AVX_Fast_Unaligned_Load, ))
     {
-      if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
-	  && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
+      if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
+	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
 	return OPTIMIZE (evex);
 
       if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
 	return OPTIMIZE (avx2_rtm);
 
-      if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
+      if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
+				       Prefer_No_VZEROUPPER, !))
 	return OPTIMIZE (avx2);
     }
 
-  if (CPU_FEATURES_ARCH_P (cpu_features, Slow_BSF))
-    return OPTIMIZE (sse2_no_bsf);
+  if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features, Slow_BSF, !))
+    return OPTIMIZE (sse2);
 
-  return OPTIMIZE (sse2);
+  return OPTIMIZE (sse2_no_bsf);
 }
 
 libc_ifunc_redirected (__redirect_strchr, strchr, IFUNC_SELECTOR ());
diff --git a/sysdeps/x86_64/multiarch/strchrnul-avx2.S b/sysdeps/x86_64/multiarch/strchrnul-avx2.S
index fa0cc09760..10ad5e6058 100644
--- a/sysdeps/x86_64/multiarch/strchrnul-avx2.S
+++ b/sysdeps/x86_64/multiarch/strchrnul-avx2.S
@@ -1,3 +1,8 @@ 
-#define STRCHR __strchrnul_avx2
+#ifndef STRCHRNUL
+# define STRCHRNUL	__strchrnul_avx2
+#endif
+
+#define STRCHR	STRCHRNUL
 #define USE_AS_STRCHRNUL 1
+
 #include "strchr-avx2.S"
diff --git a/sysdeps/x86_64/multiarch/strchrnul-evex.S b/sysdeps/x86_64/multiarch/strchrnul-evex.S
index 064fe7ca9e..0f216cb47f 100644
--- a/sysdeps/x86_64/multiarch/strchrnul-evex.S
+++ b/sysdeps/x86_64/multiarch/strchrnul-evex.S
@@ -1,3 +1,8 @@ 
-#define STRCHR __strchrnul_evex
+#ifndef STRCHRNUL
+# define STRCHRNUL	__strchrnul_evex
+#endif
+
+#define STRCHR	STRCHRNUL
 #define USE_AS_STRCHRNUL 1
+
 #include "strchr-evex.S"
diff --git a/sysdeps/x86_64/multiarch/strchrnul-sse2.S b/sysdeps/x86_64/multiarch/strchrnul-sse2.S
index 7238977a21..7ee81ae510 100644
--- a/sysdeps/x86_64/multiarch/strchrnul-sse2.S
+++ b/sysdeps/x86_64/multiarch/strchrnul-sse2.S
@@ -16,12 +16,10 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
-# ifndef STRCHR
-#  define STRCHR	__strchrnul_sse2
-# endif
+#ifndef STRCHRNUL
+# define STRCHRNUL	__strchrnul_sse2
 #endif
-
 #define AS_STRCHRNUL
+#define STRCHR	STRCHRNUL
 
 #include "strchr-sse2.S"
diff --git a/sysdeps/x86_64/multiarch/strcmp-avx2-rtm.S b/sysdeps/x86_64/multiarch/strcmp-avx2-rtm.S
index aecd30d97f..74f1f996a9 100644
--- a/sysdeps/x86_64/multiarch/strcmp-avx2-rtm.S
+++ b/sysdeps/x86_64/multiarch/strcmp-avx2-rtm.S
@@ -1,12 +1,9 @@ 
-#ifndef STRCMP
-# define STRCMP __strcmp_avx2_rtm
-#endif
-
 #define ZERO_UPPER_VEC_REGISTERS_RETURN \
   ZERO_UPPER_VEC_REGISTERS_RETURN_XTEST
 
 #define VZEROUPPER_RETURN jmp	 L(return_vzeroupper)
 
 #define SECTION(p) p##.avx.rtm
+#define STRCMP_ISA	_avx2_rtm
 
 #include "strcmp-avx2.S"
diff --git a/sysdeps/x86_64/multiarch/strcmp-avx2.S b/sysdeps/x86_64/multiarch/strcmp-avx2.S
index 3ab21e3a58..4c01d664e8 100644
--- a/sysdeps/x86_64/multiarch/strcmp-avx2.S
+++ b/sysdeps/x86_64/multiarch/strcmp-avx2.S
@@ -16,7 +16,15 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (3)
+
+# ifndef STRCMP_ISA
+#  define STRCMP_ISA	_avx2
+# endif
+
+# include "strcmp-naming.h"
 
 # include <sysdep.h>
 
@@ -86,15 +94,11 @@ 
 
 # ifdef USE_AS_STRCASECMP_L
 #  ifdef USE_AS_STRNCMP
-#   define STRCASECMP	__strncasecmp_avx2
 #   define LOCALE_REG	rcx
 #   define LOCALE_REG_LP	RCX_LP
-#   define STRCASECMP_L_NONASCII	__strncasecmp_l_nonascii
 #  else
-#   define STRCASECMP	__strcasecmp_avx2
 #   define LOCALE_REG	rdx
 #   define LOCALE_REG_LP	RDX_LP
-#   define STRCASECMP_L_NONASCII	__strcasecmp_l_nonascii
 #  endif
 # endif
 
@@ -185,18 +189,14 @@ 
 	.type	STRCMP, @function
 	.globl	STRCMP
 
-# ifndef GLABEL
-#  define GLABEL(...)	__VA_ARGS__
-# endif
-
 # ifdef USE_AS_STRCASECMP_L
-ENTRY (GLABEL(STRCASECMP))
+ENTRY (STRCASECMP)
 	movq	__libc_tsd_LOCALE@gottpoff(%rip), %rax
 	mov	%fs:(%rax), %LOCALE_REG_LP
 
 	/* Either 1 or 5 bytes (dependeing if CET is enabled).  */
 	.p2align 4
-END (GLABEL(STRCASECMP))
+END (STRCASECMP)
 	/* FALLTHROUGH to strcasecmp/strncasecmp_l.  */
 # endif
 
diff --git a/sysdeps/x86_64/multiarch/strcmp-evex.S b/sysdeps/x86_64/multiarch/strcmp-evex.S
index afbf13a230..e482d0167f 100644
--- a/sysdeps/x86_64/multiarch/strcmp-evex.S
+++ b/sysdeps/x86_64/multiarch/strcmp-evex.S
@@ -16,7 +16,12 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (4)
+
+# define STRCMP_ISA	_evex
+# include "strcmp-naming.h"
 
 # include <sysdep.h>
 # if defined USE_AS_STRCASECMP_L
@@ -37,10 +42,6 @@ 
 # define VMOVA	vmovdqa64
 
 # ifdef USE_AS_WCSCMP
-#  ifndef OVERFLOW_STRCMP
-#   define OVERFLOW_STRCMP	__wcscmp_evex
-#  endif
-
 #  define TESTEQ	subl $0xff,
 	/* Compare packed dwords.  */
 #  define VPCMP	vpcmpd
@@ -50,10 +51,6 @@ 
 	/* 1 dword char == 4 bytes.  */
 #  define SIZE_OF_CHAR	4
 # else
-#  ifndef OVERFLOW_STRCMP
-#   define OVERFLOW_STRCMP	__strcmp_evex
-#  endif
-
 #  define TESTEQ	incl
 	/* Compare packed bytes.  */
 #  define VPCMP	vpcmpb
@@ -120,15 +117,11 @@ 
 
 # ifdef USE_AS_STRCASECMP_L
 #  ifdef USE_AS_STRNCMP
-#   define STRCASECMP	__strncasecmp_evex
 #   define LOCALE_REG	rcx
 #   define LOCALE_REG_LP	RCX_LP
-#   define STRCASECMP_L_NONASCII	__strncasecmp_l_nonascii
 #  else
-#   define STRCASECMP	__strcasecmp_evex
 #   define LOCALE_REG	rdx
 #   define LOCALE_REG_LP	RDX_LP
-#   define STRCASECMP_L_NONASCII	__strcasecmp_l_nonascii
 #  endif
 # endif
 
@@ -214,7 +207,6 @@ 
 	.align	16
 	.type	STRCMP, @function
 	.globl	STRCMP
-
 # ifdef USE_AS_STRCASECMP_L
 ENTRY (STRCASECMP)
 	movq	__libc_tsd_LOCALE@gottpoff(%rip), %rax
diff --git a/sysdeps/x86_64/multiarch/strcmp-sse2-unaligned.S b/sysdeps/x86_64/multiarch/strcmp-sse2-unaligned.S
index 0d691b78a8..33c18a28e8 100644
--- a/sysdeps/x86_64/multiarch/strcmp-sse2-unaligned.S
+++ b/sysdeps/x86_64/multiarch/strcmp-sse2-unaligned.S
@@ -16,11 +16,20 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
 
-#include "sysdep.h"
+/* Continue building as ISA level 2.  We use this as ISA V2 default
+   because strcmp-sse42 uses pcmpstri (slow on some SSE4.2
+   processors) and this implementation is potenially faster than
+   strcmp-sse42 (aside from the slower page cross case).  */
+#if ISA_SHOULD_BUILD (2)
 
-ENTRY ( __strcmp_sse2_unaligned)
+# define STRCMP_ISA	_sse2_unaligned
+# include "strcmp-naming.h"
+
+# include "sysdep.h"
+
+ENTRY (STRCMP)
 	movl	%edi, %eax
 	xorl	%edx, %edx
 	pxor	%xmm7, %xmm7
@@ -208,6 +217,5 @@  L(cross_page):
 L(different):
 	subl	%ecx, %eax
 	ret
-END (__strcmp_sse2_unaligned)
-
+END (STRCMP)
 #endif
diff --git a/sysdeps/x86_64/multiarch/strcmp-sse2.S b/sysdeps/x86_64/multiarch/strcmp-sse2.S
index b1220231ab..3c69fc1df1 100644
--- a/sysdeps/x86_64/multiarch/strcmp-sse2.S
+++ b/sysdeps/x86_64/multiarch/strcmp-sse2.S
@@ -16,7 +16,11 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc) || IS_IN (rtld)
+#include <isa-level.h>
+
+/* Continue building at ISA level 2 as the strcmp-sse42 is not always
+   preferable for ISA level == 2 CPUs.  */
+#if ISA_SHOULD_BUILD (2)
 
 # define STRCMP_ISA	_sse2
 # include "strcmp-naming.h"
diff --git a/sysdeps/x86_64/multiarch/strcmp-sse4_2.S b/sysdeps/x86_64/multiarch/strcmp-sse4_2.S
index 963e208ccb..dc6fc90e14 100644
--- a/sysdeps/x86_64/multiarch/strcmp-sse4_2.S
+++ b/sysdeps/x86_64/multiarch/strcmp-sse4_2.S
@@ -16,7 +16,10 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (2)
+
 # include <sysdep.h>
 
 # define STRCMP_ISA	_sse42
@@ -1766,7 +1769,6 @@  LABEL(unaligned_table):
 	.int	LABEL(ashr_0) - LABEL(unaligned_table)
 
 # undef LABEL
-# undef GLABEL
 # undef SECTION
 # undef movdqa
 # undef movdqu
diff --git a/sysdeps/x86_64/multiarch/strcmp.c b/sysdeps/x86_64/multiarch/strcmp.c
index 9c1677724c..fdd5afe3af 100644
--- a/sysdeps/x86_64/multiarch/strcmp.c
+++ b/sysdeps/x86_64/multiarch/strcmp.c
@@ -26,37 +26,50 @@ 
 # define SYMBOL_NAME strcmp
 # include <init-arch.h>
 
-extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
-extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned) attribute_hidden;
-extern __typeof (REDIRECT_NAME) OPTIMIZE (sse42) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
-extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse42) attribute_hidden;
+
+extern __typeof (REDIRECT_NAME)
+    OPTIMIZE (sse2_unaligned) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
+
+
 
 static inline void *
 IFUNC_SELECTOR (void)
 {
-  const struct cpu_features* cpu_features = __get_cpu_features ();
+  const struct cpu_features *cpu_features = __get_cpu_features ();
 
-  if (CPU_FEATURE_USABLE_P (cpu_features, AVX2)
-      && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
+  if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX2)
+      && X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
+				      AVX_Fast_Unaligned_Load, ))
     {
-      if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
-	  && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW)
-	  && CPU_FEATURE_USABLE_P (cpu_features, BMI2))
+      if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
+	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512BW)
+	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, BMI2))
 	return OPTIMIZE (evex);
 
       if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
 	return OPTIMIZE (avx2_rtm);
 
-      if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
+      if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
+				       Prefer_No_VZEROUPPER, !))
 	return OPTIMIZE (avx2);
     }
 
-  if (CPU_FEATURE_USABLE_P (cpu_features, SSE4_2)
+  if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, SSE4_2)
+      /* Keep this as runtime check.  Some ISA level >= 2 CPUs such as
+	 Tremont, Silvermont, and more check this.  */
       && !CPU_FEATURES_ARCH_P (cpu_features, Slow_SSE4_2))
     return OPTIMIZE (sse42);
 
+  /* Keep this as runtime check.  The standard SSE2 version has
+     meaningful optimizations around keeping all loads aligned in the
+     main loop which can benefit some ISA level >= 2 CPUs.  */
   if (CPU_FEATURES_ARCH_P (cpu_features, Fast_Unaligned_Load))
     return OPTIMIZE (sse2_unaligned);
 
diff --git a/sysdeps/x86_64/multiarch/strlen-avx2.S b/sysdeps/x86_64/multiarch/strlen-avx2.S
index 9e36290dd2..0593fb303b 100644
--- a/sysdeps/x86_64/multiarch/strlen-avx2.S
+++ b/sysdeps/x86_64/multiarch/strlen-avx2.S
@@ -16,7 +16,9 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (3)
 
 # include <sysdep.h>
 
diff --git a/sysdeps/x86_64/multiarch/strlen-evex-base.S b/sysdeps/x86_64/multiarch/strlen-evex-base.S
index 278c899691..418e9f8411 100644
--- a/sysdeps/x86_64/multiarch/strlen-evex-base.S
+++ b/sysdeps/x86_64/multiarch/strlen-evex-base.S
@@ -16,7 +16,11 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+/* UNUSED. Exists purely as reference implementation.  */
+
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (4)
 
 # include <sysdep.h>
 
diff --git a/sysdeps/x86_64/multiarch/strlen-evex.S b/sysdeps/x86_64/multiarch/strlen-evex.S
index 59ade77498..2109ec2f7a 100644
--- a/sysdeps/x86_64/multiarch/strlen-evex.S
+++ b/sysdeps/x86_64/multiarch/strlen-evex.S
@@ -16,7 +16,9 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (4)
 
 # include <sysdep.h>
 
diff --git a/sysdeps/x86_64/multiarch/strlen-sse2.S b/sysdeps/x86_64/multiarch/strlen-sse2.S
index 5be72267d5..a96ccbb2d5 100644
--- a/sysdeps/x86_64/multiarch/strlen-sse2.S
+++ b/sysdeps/x86_64/multiarch/strlen-sse2.S
@@ -16,15 +16,20 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc) || defined STRLEN
-
-# ifndef STRLEN
-#  define STRLEN __strlen_sse2
-# endif
+#include <isa-level.h>
 
+/* ISA level >= 2 for both strlen and wcslen.  wcslen uses `pminud`
+   which is SSE4.1. strlen doesn't have an ISA level == 2
+   implementation so the SSE2 implementation must be built with ISA
+   level == 2.  */
+# if ISA_SHOULD_BUILD (2)
 
 # include <sysdep.h>
 
+# ifndef STRLEN
+#  define STRLEN	__strlen_sse2
+# endif
+
 # ifdef AS_WCSLEN
 #  define PMINU		pminud
 #  define PCMPEQ		pcmpeqd
@@ -82,7 +87,7 @@  L(n_nonzero):
    suffice.  */
 	mov	%RSI_LP, %R10_LP
 	sar	$62, %R10_LP
-	jnz	__wcslen_sse4_1
+	jnz	OVERFLOW_STRLEN
 	sal	$2, %RSI_LP
 #  endif
 
diff --git a/sysdeps/x86_64/multiarch/strncase_l-avx2-rtm.S b/sysdeps/x86_64/multiarch/strncase_l-avx2-rtm.S
index 58c05dcfb8..c2596ab103 100644
--- a/sysdeps/x86_64/multiarch/strncase_l-avx2-rtm.S
+++ b/sysdeps/x86_64/multiarch/strncase_l-avx2-rtm.S
@@ -1,16 +1,4 @@ 
-#ifndef STRCMP
-# define STRCMP	__strncasecmp_l_avx2_rtm
-#endif
+#define USE_AS_STRCASECMP_L
+#define USE_AS_STRNCMP
 
-#define _GLABEL(x)	x ## _rtm
-#define GLABEL(x)	_GLABEL(x)
-
-#define ZERO_UPPER_VEC_REGISTERS_RETURN	\
-	ZERO_UPPER_VEC_REGISTERS_RETURN_XTEST
-
-#define VZEROUPPER_RETURN	jmp L(return_vzeroupper)
-
-#define SECTION(p)	p##.avx.rtm
-#define OVERFLOW_STRCMP	__strcasecmp_l_avx2_rtm
-
-#include "strncase_l-avx2.S"
+#include "strcmp-avx2-rtm.S"
diff --git a/sysdeps/x86_64/multiarch/strncase_l-avx2.S b/sysdeps/x86_64/multiarch/strncase_l-avx2.S
index 48c0aa21f8..d00687aac5 100644
--- a/sysdeps/x86_64/multiarch/strncase_l-avx2.S
+++ b/sysdeps/x86_64/multiarch/strncase_l-avx2.S
@@ -16,12 +16,7 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#ifndef STRCMP
-# define STRCMP	__strncasecmp_l_avx2
-#endif
 #define USE_AS_STRCASECMP_L
 #define USE_AS_STRNCMP
-#ifndef OVERFLOW_STRCMP
-# define OVERFLOW_STRCMP	__strcasecmp_l_avx2
-#endif
+
 #include "strcmp-avx2.S"
diff --git a/sysdeps/x86_64/multiarch/strncase_l-evex.S b/sysdeps/x86_64/multiarch/strncase_l-evex.S
index 8a5af3695c..1a79758065 100644
--- a/sysdeps/x86_64/multiarch/strncase_l-evex.S
+++ b/sysdeps/x86_64/multiarch/strncase_l-evex.S
@@ -16,10 +16,6 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#ifndef STRCMP
-# define STRCMP	__strncasecmp_l_evex
-#endif
-#define OVERFLOW_STRCMP	__strcasecmp_l_evex
 #define USE_AS_STRCASECMP_L
 #define USE_AS_STRNCMP
 #include "strcmp-evex.S"
diff --git a/sysdeps/x86_64/multiarch/strncmp-avx2-rtm.S b/sysdeps/x86_64/multiarch/strncmp-avx2-rtm.S
index 68bad365ba..6bb6be8585 100644
--- a/sysdeps/x86_64/multiarch/strncmp-avx2-rtm.S
+++ b/sysdeps/x86_64/multiarch/strncmp-avx2-rtm.S
@@ -1,4 +1,2 @@ 
-#define STRCMP	__strncmp_avx2_rtm
 #define USE_AS_STRNCMP 1
-#define OVERFLOW_STRCMP	__strcmp_avx2_rtm
 #include "strcmp-avx2-rtm.S"
diff --git a/sysdeps/x86_64/multiarch/strncmp-avx2.S b/sysdeps/x86_64/multiarch/strncmp-avx2.S
index f138e9f1fd..def3509c4c 100644
--- a/sysdeps/x86_64/multiarch/strncmp-avx2.S
+++ b/sysdeps/x86_64/multiarch/strncmp-avx2.S
@@ -1,4 +1,3 @@ 
-#define STRCMP	__strncmp_avx2
 #define USE_AS_STRNCMP 1
-#define OVERFLOW_STRCMP __strcmp_avx2
+
 #include "strcmp-avx2.S"
diff --git a/sysdeps/x86_64/multiarch/strncmp-evex.S b/sysdeps/x86_64/multiarch/strncmp-evex.S
index a1d53e8c9f..aa69c18928 100644
--- a/sysdeps/x86_64/multiarch/strncmp-evex.S
+++ b/sysdeps/x86_64/multiarch/strncmp-evex.S
@@ -1,3 +1,2 @@ 
-#define STRCMP	__strncmp_evex
 #define USE_AS_STRNCMP 1
 #include "strcmp-evex.S"
diff --git a/sysdeps/x86_64/multiarch/strncmp.c b/sysdeps/x86_64/multiarch/strncmp.c
index 70ae6547c9..4ebe4bde30 100644
--- a/sysdeps/x86_64/multiarch/strncmp.c
+++ b/sysdeps/x86_64/multiarch/strncmp.c
@@ -26,33 +26,38 @@ 
 # define SYMBOL_NAME strncmp
 # include <init-arch.h>
 
-extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
-extern __typeof (REDIRECT_NAME) OPTIMIZE (sse42) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
-extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse42) attribute_hidden;
+
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
 
 static inline void *
 IFUNC_SELECTOR (void)
 {
-  const struct cpu_features* cpu_features = __get_cpu_features ();
+  const struct cpu_features *cpu_features = __get_cpu_features ();
 
-  if (CPU_FEATURE_USABLE_P (cpu_features, AVX2)
-      && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
+  if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX2)
+      && X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
+				      AVX_Fast_Unaligned_Load, ))
     {
-      if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
-	  && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW)
-	  && CPU_FEATURE_USABLE_P (cpu_features, BMI2))
+      if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
+	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512BW)
+	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, BMI2))
 	return OPTIMIZE (evex);
 
       if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
 	return OPTIMIZE (avx2_rtm);
 
-      if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
+      if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
+				       Prefer_No_VZEROUPPER, !))
 	return OPTIMIZE (avx2);
     }
 
-  if (CPU_FEATURE_USABLE_P (cpu_features, SSE4_2)
+  if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, SSE4_2)
       && !CPU_FEATURES_ARCH_P (cpu_features, Slow_SSE4_2))
     return OPTIMIZE (sse42);
 
diff --git a/sysdeps/x86_64/multiarch/strnlen-avx2.S b/sysdeps/x86_64/multiarch/strnlen-avx2.S
index c4062b22f7..c4a12097f0 100644
--- a/sysdeps/x86_64/multiarch/strnlen-avx2.S
+++ b/sysdeps/x86_64/multiarch/strnlen-avx2.S
@@ -1,4 +1,8 @@ 
-#define STRLEN __strnlen_avx2
+#ifndef STRNLEN
+# define STRNLEN __strnlen_avx2
+#endif
+
 #define USE_AS_STRNLEN 1
+#define STRLEN	STRNLEN
 
 #include "strlen-avx2.S"
diff --git a/sysdeps/x86_64/multiarch/strnlen-evex.S b/sysdeps/x86_64/multiarch/strnlen-evex.S
index 722022f303..64a9fc2606 100644
--- a/sysdeps/x86_64/multiarch/strnlen-evex.S
+++ b/sysdeps/x86_64/multiarch/strnlen-evex.S
@@ -1,4 +1,8 @@ 
-#define STRLEN __strnlen_evex
+#ifndef STRNLEN
+# define STRNLEN __strnlen_evex
+#endif
+
 #define USE_AS_STRNLEN 1
+#define STRLEN	STRNLEN
 
 #include "strlen-evex.S"
diff --git a/sysdeps/x86_64/multiarch/strnlen-sse2.S b/sysdeps/x86_64/multiarch/strnlen-sse2.S
index a50c7d6a28..8841ba9faf 100644
--- a/sysdeps/x86_64/multiarch/strnlen-sse2.S
+++ b/sysdeps/x86_64/multiarch/strnlen-sse2.S
@@ -16,11 +16,11 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
-# ifndef STRLEN
-#  define STRLEN	__strnlen_sse2
-# endif
+#ifndef STRNLEN
+# define STRNLEN	__strnlen_sse2
 #endif
 
-#define AS_STRNLEN
+#define AS_STRNLEN	1
+#define STRLEN	STRNLEN
+
 #include "strlen-sse2.S"
diff --git a/sysdeps/x86_64/multiarch/strrchr-avx2.S b/sysdeps/x86_64/multiarch/strrchr-avx2.S
index eb128a2ae3..924171d8e4 100644
--- a/sysdeps/x86_64/multiarch/strrchr-avx2.S
+++ b/sysdeps/x86_64/multiarch/strrchr-avx2.S
@@ -16,7 +16,9 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (3)
 
 # include <sysdep.h>
 
diff --git a/sysdeps/x86_64/multiarch/strrchr-evex.S b/sysdeps/x86_64/multiarch/strrchr-evex.S
index 8014c285b3..992b45fb47 100644
--- a/sysdeps/x86_64/multiarch/strrchr-evex.S
+++ b/sysdeps/x86_64/multiarch/strrchr-evex.S
@@ -16,7 +16,9 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (4)
 
 # include <sysdep.h>
 
diff --git a/sysdeps/x86_64/multiarch/strrchr-sse2.S b/sysdeps/x86_64/multiarch/strrchr-sse2.S
index 6ee7a5e33a..892e861fa8 100644
--- a/sysdeps/x86_64/multiarch/strrchr-sse2.S
+++ b/sysdeps/x86_64/multiarch/strrchr-sse2.S
@@ -16,36 +16,40 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+#include <isa-level.h>
+
+/* ISA level >= 2 because there are no {wcs|str}rchr-sse4
+   implementations.  */
+#if ISA_SHOULD_BUILD (2)
+
+# include <sysdep.h>
+
 # ifndef STRRCHR
 #  define STRRCHR __strrchr_sse2
 # endif
-#endif
-
-#include <sysdep.h>
 
-#ifdef USE_AS_WCSRCHR
-# define PCMPEQ	pcmpeqd
-# define CHAR_SIZE	4
-# define PMINU	pminud
-#else
-# define PCMPEQ	pcmpeqb
-# define CHAR_SIZE	1
-# define PMINU	pminub
-#endif
+# ifdef USE_AS_WCSRCHR
+#  define PCMPEQ	pcmpeqd
+#  define CHAR_SIZE	4
+#  define PMINU	pminud
+# else
+#  define PCMPEQ	pcmpeqb
+#  define CHAR_SIZE	1
+#  define PMINU	pminub
+# endif
 
-#define PAGE_SIZE	4096
-#define VEC_SIZE	16
+# define PAGE_SIZE	4096
+# define VEC_SIZE	16
 
 	.text
 ENTRY(STRRCHR)
 	movd	%esi, %xmm0
 	movq	%rdi, %rax
 	andl	$(PAGE_SIZE - 1), %eax
-#ifndef USE_AS_WCSRCHR
+# ifndef USE_AS_WCSRCHR
 	punpcklbw %xmm0, %xmm0
 	punpcklwd %xmm0, %xmm0
-#endif
+# endif
 	pshufd	$0, %xmm0, %xmm0
 	cmpl	$(PAGE_SIZE - VEC_SIZE), %eax
 	ja	L(cross_page)
@@ -69,9 +73,9 @@  L(cross_page_continue):
 	/* We are off by 3 for wcsrchr if search CHAR is non-zero. If
 	   search CHAR is zero we are correct. Either way `andq
 	   -CHAR_SIZE, %rax` gets the correct result.  */
-#ifdef USE_AS_WCSRCHR
+# ifdef USE_AS_WCSRCHR
 	andq	$-CHAR_SIZE, %rax
-#endif
+# endif
 L(ret0):
 	ret
 
@@ -85,9 +89,9 @@  L(first_vec_x0_test):
 	jz	L(ret0)
 	bsrl	%eax, %eax
 	addq	%r8, %rax
-#ifdef USE_AS_WCSRCHR
+# ifdef USE_AS_WCSRCHR
 	andq	$-CHAR_SIZE, %rax
-#endif
+# endif
 	ret
 
 	.p2align 4
@@ -100,9 +104,9 @@  L(first_vec_x1):
 	jz	L(first_vec_x0_test)
 	bsrl	%eax, %eax
 	leaq	(VEC_SIZE)(%rdi, %rax), %rax
-#ifdef USE_AS_WCSRCHR
+# ifdef USE_AS_WCSRCHR
 	andq	$-CHAR_SIZE, %rax
-#endif
+# endif
 	ret
 
 	.p2align 4
@@ -113,9 +117,9 @@  L(first_vec_x1_test):
 	jz	L(first_vec_x0_test)
 	bsrl	%eax, %eax
 	leaq	(VEC_SIZE)(%rdi, %rax), %rax
-#ifdef USE_AS_WCSRCHR
+# ifdef USE_AS_WCSRCHR
 	andq	$-CHAR_SIZE, %rax
-#endif
+# endif
 	ret
 
 	.p2align 4
@@ -128,9 +132,9 @@  L(first_vec_x2):
 	jz	L(first_vec_x1_test)
 	bsrl	%eax, %eax
 	leaq	(VEC_SIZE * 2)(%rdi, %rax), %rax
-#ifdef USE_AS_WCSRCHR
+# ifdef USE_AS_WCSRCHR
 	andq	$-CHAR_SIZE, %rax
-#endif
+# endif
 	ret
 
 	.p2align 4
@@ -165,27 +169,27 @@  L(first_loop):
 	/* Since SSE2 no pminud so wcsrchr needs seperate logic for
 	   detecting zero. Note if this is found to be a bottleneck it
 	   may be worth adding an SSE4.1 wcsrchr implementation.  */
-#ifdef USE_AS_WCSRCHR
+# ifdef USE_AS_WCSRCHR
 	movaps	%xmm5, %xmm6
 	pxor	%xmm8, %xmm8
 
 	PCMPEQ	%xmm8, %xmm5
 	PCMPEQ	%xmm4, %xmm8
 	por	%xmm5, %xmm8
-#else
+# else
 	movaps	%xmm5, %xmm6
 	PMINU	%xmm4, %xmm5
-#endif
+# endif
 
 	movaps	%xmm4, %xmm9
 	PCMPEQ	%xmm0, %xmm4
 	PCMPEQ	%xmm0, %xmm6
 	movaps	%xmm6, %xmm7
 	por	%xmm4, %xmm6
-#ifndef USE_AS_WCSRCHR
+# ifndef USE_AS_WCSRCHR
 	pxor	%xmm8, %xmm8
 	PCMPEQ	%xmm5, %xmm8
-#endif
+# endif
 	pmovmskb %xmm8, %ecx
 	pmovmskb %xmm6, %eax
 
@@ -219,9 +223,9 @@  L(first_loop_old_match):
 
 	bsrl	%eax, %eax
 	addq	%rsi, %rax
-#ifdef USE_AS_WCSRCHR
+# ifdef USE_AS_WCSRCHR
 	andq	$-CHAR_SIZE, %rax
-#endif
+# endif
 	ret
 
 	.p2align 4
@@ -247,9 +251,9 @@  L(new_match):
 	jz	L(first_loop_old_match)
 	bsrl	%eax, %eax
 	addq	%rdi, %rax
-#ifdef USE_AS_WCSRCHR
+# ifdef USE_AS_WCSRCHR
 	andq	$-CHAR_SIZE, %rax
-#endif
+# endif
 	ret
 
 	/* Save minimum state for getting most recent match. We can
@@ -267,27 +271,27 @@  L(second_loop):
 	/* Since SSE2 no pminud so wcsrchr needs seperate logic for
 	   detecting zero. Note if this is found to be a bottleneck it
 	   may be worth adding an SSE4.1 wcsrchr implementation.  */
-#ifdef USE_AS_WCSRCHR
+# ifdef USE_AS_WCSRCHR
 	movaps	%xmm5, %xmm6
 	pxor	%xmm8, %xmm8
 
 	PCMPEQ	%xmm8, %xmm5
 	PCMPEQ	%xmm4, %xmm8
 	por	%xmm5, %xmm8
-#else
+# else
 	movaps	%xmm5, %xmm6
 	PMINU	%xmm4, %xmm5
-#endif
+# endif
 
 	movaps	%xmm4, %xmm9
 	PCMPEQ	%xmm0, %xmm4
 	PCMPEQ	%xmm0, %xmm6
 	movaps	%xmm6, %xmm7
 	por	%xmm4, %xmm6
-#ifndef USE_AS_WCSRCHR
+# ifndef USE_AS_WCSRCHR
 	pxor	%xmm8, %xmm8
 	PCMPEQ	%xmm5, %xmm8
-#endif
+# endif
 
 	pmovmskb %xmm8, %ecx
 	pmovmskb %xmm6, %eax
@@ -312,9 +316,9 @@  L(second_loop_old_match):
 	orl	%ecx, %eax
 	bsrl	%eax, %eax
 	addq	%rsi, %rax
-#ifdef USE_AS_WCSRCHR
+# ifdef USE_AS_WCSRCHR
 	andq	$-CHAR_SIZE, %rax
-#endif
+# endif
 	ret
 
 	.p2align 4
@@ -340,9 +344,9 @@  L(second_loop_new_match):
 	jz	L(second_loop_old_match)
 	bsrl	%eax, %eax
 	addq	%rdi, %rax
-#ifdef USE_AS_WCSRCHR
+# ifdef USE_AS_WCSRCHR
 	andq	$-CHAR_SIZE, %rax
-#endif
+# endif
 	ret
 
 	.p2align 4,, 4
@@ -366,9 +370,10 @@  L(cross_page):
 	jz	L(ret1)
 	bsrl	%eax, %eax
 	addq	%rdi, %rax
-#ifdef USE_AS_WCSRCHR
+# ifdef USE_AS_WCSRCHR
 	andq	$-CHAR_SIZE, %rax
-#endif
+# endif
 L(ret1):
 	ret
 END(STRRCHR)
+#endif
diff --git a/sysdeps/x86_64/multiarch/strstr-sse2-unaligned.S b/sysdeps/x86_64/multiarch/strstr-sse2-unaligned.S
index c6aa8f45a6..dc342a9f44 100644
--- a/sysdeps/x86_64/multiarch/strstr-sse2-unaligned.S
+++ b/sysdeps/x86_64/multiarch/strstr-sse2-unaligned.S
@@ -17,6 +17,7 @@ 
    <https://www.gnu.org/licenses/>.  */
 
 #include <sysdep.h>
+#include "../strchr-isa-default-impl.h"
 
 ENTRY(__strstr_sse2_unaligned)
 	movzbl	(%rsi), %eax
@@ -75,7 +76,7 @@  L(next_pair_index):
 	.p2align 4
 L(strchr):
 	movzbl	%al, %esi
-	jmp	__strchr_sse2
+	jmp	DEFAULT_STRCHR
 
 	.p2align 4
 L(pair_loop):
diff --git a/sysdeps/x86_64/multiarch/wcschr-avx2.S b/sysdeps/x86_64/multiarch/wcschr-avx2.S
index 67726b6837..f404888a93 100644
--- a/sysdeps/x86_64/multiarch/wcschr-avx2.S
+++ b/sysdeps/x86_64/multiarch/wcschr-avx2.S
@@ -1,3 +1,8 @@ 
-#define STRCHR __wcschr_avx2
+#ifndef WCSCHR
+# define WCSCHR	__wcschr_avx2
+#endif
+
+#define STRCHR	WCSCHR
 #define USE_AS_WCSCHR 1
+
 #include "strchr-avx2.S"
diff --git a/sysdeps/x86_64/multiarch/wcschr-evex.S b/sysdeps/x86_64/multiarch/wcschr-evex.S
index 7cb8f1e41a..b5ccc59230 100644
--- a/sysdeps/x86_64/multiarch/wcschr-evex.S
+++ b/sysdeps/x86_64/multiarch/wcschr-evex.S
@@ -1,3 +1,8 @@ 
-#define STRCHR __wcschr_evex
+#ifndef WCSCHR
+# define WCSCHR	__wcschr_evex
+#endif
+
+#define STRCHR	WCSCHR
 #define USE_AS_WCSCHR 1
+
 #include "strchr-evex.S"
diff --git a/sysdeps/x86_64/multiarch/wcschr-sse2.S b/sysdeps/x86_64/multiarch/wcschr-sse2.S
index c872926ba9..1c83957cbc 100644
--- a/sysdeps/x86_64/multiarch/wcschr-sse2.S
+++ b/sysdeps/x86_64/multiarch/wcschr-sse2.S
@@ -16,13 +16,17 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
+
+#include <isa-level.h>
+
+/* ISA level >= 2 because there is no wcschr-sse4 implementations.  */
+#if ISA_SHOULD_BUILD (2)
+
 # ifndef WCSCHR
 #  define WCSCHR __wcschr_sse2
 # endif
-#endif
 
-#include <sysdep.h>
+# include <sysdep.h>
 
 	.text
 ENTRY (WCSCHR)
@@ -155,3 +159,4 @@  L(return_null):
 	ret
 
 END (WCSCHR)
+#endif
diff --git a/sysdeps/x86_64/multiarch/wcscmp-avx2-rtm.S b/sysdeps/x86_64/multiarch/wcscmp-avx2-rtm.S
index d6ca2b8064..f17a8969cb 100644
--- a/sysdeps/x86_64/multiarch/wcscmp-avx2-rtm.S
+++ b/sysdeps/x86_64/multiarch/wcscmp-avx2-rtm.S
@@ -1,4 +1,3 @@ 
-#define STRCMP __wcscmp_avx2_rtm
 #define USE_AS_WCSCMP 1
 
 #include "strcmp-avx2-rtm.S"
diff --git a/sysdeps/x86_64/multiarch/wcscmp-avx2.S b/sysdeps/x86_64/multiarch/wcscmp-avx2.S
index e5da4da689..0a71f907f0 100644
--- a/sysdeps/x86_64/multiarch/wcscmp-avx2.S
+++ b/sysdeps/x86_64/multiarch/wcscmp-avx2.S
@@ -1,4 +1,3 @@ 
-#define STRCMP __wcscmp_avx2
 #define USE_AS_WCSCMP 1
 
 #include "strcmp-avx2.S"
diff --git a/sysdeps/x86_64/multiarch/wcscmp-evex.S b/sysdeps/x86_64/multiarch/wcscmp-evex.S
index 42e73e51eb..b0337a8311 100644
--- a/sysdeps/x86_64/multiarch/wcscmp-evex.S
+++ b/sysdeps/x86_64/multiarch/wcscmp-evex.S
@@ -1,4 +1,3 @@ 
-#define STRCMP __wcscmp_evex
 #define USE_AS_WCSCMP 1
 
 #include "strcmp-evex.S"
diff --git a/sysdeps/x86_64/multiarch/wcscmp-sse2.S b/sysdeps/x86_64/multiarch/wcscmp-sse2.S
index 6cb7d9faf9..3f32e8127d 100644
--- a/sysdeps/x86_64/multiarch/wcscmp-sse2.S
+++ b/sysdeps/x86_64/multiarch/wcscmp-sse2.S
@@ -16,11 +16,16 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#define USE_AS_WCSCMP
-#define STRCMP_ISA	_sse2
-#include "strcmp-naming.h"
+#include <isa-level.h>
 
-#include <sysdep.h>
+/* ISA level >= 2 because there is no wcscmp-sse4 implementations.  */
+#if ISA_SHOULD_BUILD (2)
+# include <sysdep.h>
+
+/* Needed to get right name.  */
+# define USE_AS_WCSCMP
+# define STRCMP_ISA	_sse2
+# include "strcmp-naming.h"
 
 /* Note: wcscmp uses signed comparison, not unsighed as in strcmp function. */
 
@@ -949,3 +954,4 @@  L(equal):
 	ret
 
 END (STRCMP)
+#endif
diff --git a/sysdeps/x86_64/multiarch/wcslen-avx2.S b/sysdeps/x86_64/multiarch/wcslen-avx2.S
index c9224f1bc5..9784d8f780 100644
--- a/sysdeps/x86_64/multiarch/wcslen-avx2.S
+++ b/sysdeps/x86_64/multiarch/wcslen-avx2.S
@@ -1,4 +1,8 @@ 
-#define STRLEN __wcslen_avx2
+#ifndef WCSLEN
+# define WCSLEN	__wcslen_avx2
+#endif
+
+#define STRLEN WCSLEN
 #define USE_AS_WCSLEN 1
 
 #include "strlen-avx2.S"
diff --git a/sysdeps/x86_64/multiarch/wcslen-evex.S b/sysdeps/x86_64/multiarch/wcslen-evex.S
index bdafa83bd5..df21bac63c 100644
--- a/sysdeps/x86_64/multiarch/wcslen-evex.S
+++ b/sysdeps/x86_64/multiarch/wcslen-evex.S
@@ -1,4 +1,8 @@ 
-#define STRLEN __wcslen_evex
+#ifndef WCSLEN
+# define WCSLEN	__wcslen_evex
+#endif
+
+#define STRLEN WCSLEN
 #define USE_AS_WCSLEN 1
 
 #include "strlen-evex.S"
diff --git a/sysdeps/x86_64/multiarch/wcslen-sse2.S b/sysdeps/x86_64/multiarch/wcslen-sse2.S
index 944c3bd9c6..e9c518a932 100644
--- a/sysdeps/x86_64/multiarch/wcslen-sse2.S
+++ b/sysdeps/x86_64/multiarch/wcslen-sse2.S
@@ -16,13 +16,16 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
-# ifndef WCSLEN
-#  define WCSLEN __wcslen_sse2
-# endif
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (1)
+
+# include <sysdep.h>
+
+#ifndef WCSLEN
+# define WCSLEN	__wcslen_sse2
 #endif
 
-#include <sysdep.h>
 
 	.text
 ENTRY (WCSLEN)
@@ -235,3 +238,5 @@  L(exit_tail7):
 	ret
 
 END (WCSLEN)
+
+#endif
diff --git a/sysdeps/x86_64/multiarch/wcslen-sse4_1.S b/sysdeps/x86_64/multiarch/wcslen-sse4_1.S
index c88e8342a1..126d183e75 100644
--- a/sysdeps/x86_64/multiarch/wcslen-sse4_1.S
+++ b/sysdeps/x86_64/multiarch/wcslen-sse4_1.S
@@ -1,5 +1,9 @@ 
-#define AS_WCSLEN
-#define STRLEN	__wcslen_sse4_1
-#define SECTION(p)	p##.sse4.1
+#ifndef WCSLEN
+# define WCSLEN	__wcslen_sse4_1
+#endif
+
+#define AS_WCSLEN	1
+#define STRLEN	WCSLEN
+#define SECTION(p)		p##.sse4.1
 
 #include "strlen-sse2.S"
diff --git a/sysdeps/x86_64/multiarch/wcsncmp-avx2-rtm.S b/sysdeps/x86_64/multiarch/wcsncmp-avx2-rtm.S
index f467582cbe..099a60c48e 100644
--- a/sysdeps/x86_64/multiarch/wcsncmp-avx2-rtm.S
+++ b/sysdeps/x86_64/multiarch/wcsncmp-avx2-rtm.S
@@ -1,5 +1,3 @@ 
-#define STRCMP __wcsncmp_avx2_rtm
 #define USE_AS_STRNCMP 1
 #define USE_AS_WCSCMP 1
-#define OVERFLOW_STRCMP	__wcscmp_avx2_rtm
 #include "strcmp-avx2-rtm.S"
diff --git a/sysdeps/x86_64/multiarch/wcsncmp-avx2.S b/sysdeps/x86_64/multiarch/wcsncmp-avx2.S
index e9ede522b8..fc26b593d0 100644
--- a/sysdeps/x86_64/multiarch/wcsncmp-avx2.S
+++ b/sysdeps/x86_64/multiarch/wcsncmp-avx2.S
@@ -1,5 +1,4 @@ 
-#define STRCMP __wcsncmp_avx2
 #define USE_AS_STRNCMP 1
 #define USE_AS_WCSCMP 1
-#define OVERFLOW_STRCMP	__wcscmp_avx2
+
 #include "strcmp-avx2.S"
diff --git a/sysdeps/x86_64/multiarch/wcsncmp-evex.S b/sysdeps/x86_64/multiarch/wcsncmp-evex.S
index 8a8e310713..d3a92e2000 100644
--- a/sysdeps/x86_64/multiarch/wcsncmp-evex.S
+++ b/sysdeps/x86_64/multiarch/wcsncmp-evex.S
@@ -1,4 +1,3 @@ 
-#define STRCMP __wcsncmp_evex
 #define USE_AS_STRNCMP 1
 #define USE_AS_WCSCMP 1
 
diff --git a/sysdeps/x86_64/multiarch/wcsncmp-generic.c b/sysdeps/x86_64/multiarch/wcsncmp-generic.c
index 658d541886..b0cf4e87d5 100644
--- a/sysdeps/x86_64/multiarch/wcsncmp-generic.c
+++ b/sysdeps/x86_64/multiarch/wcsncmp-generic.c
@@ -16,5 +16,10 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#define WCSNCMP __wcsncmp_generic
-#include <wcsmbs/wcsncmp.c>
+#include <isa-level.h>
+#if ISA_SHOULD_BUILD (2)
+
+# define WCSNCMP __wcsncmp_generic
+# include <wcsmbs/wcsncmp.c>
+
+#endif
diff --git a/sysdeps/x86_64/multiarch/wcsnlen-avx2.S b/sysdeps/x86_64/multiarch/wcsnlen-avx2.S
index fac83546b5..12c3a0fd05 100644
--- a/sysdeps/x86_64/multiarch/wcsnlen-avx2.S
+++ b/sysdeps/x86_64/multiarch/wcsnlen-avx2.S
@@ -1,4 +1,8 @@ 
-#define STRLEN __wcsnlen_avx2
+#ifndef WCSNLEN
+# define WCSNLEN	__wcsnlen_avx2
+#endif
+
+#define STRLEN	WCSNLEN
 #define USE_AS_WCSLEN 1
 #define USE_AS_STRNLEN 1
 
diff --git a/sysdeps/x86_64/multiarch/wcsnlen-evex.S b/sysdeps/x86_64/multiarch/wcsnlen-evex.S
index 24773bb4e2..e2aad94c1e 100644
--- a/sysdeps/x86_64/multiarch/wcsnlen-evex.S
+++ b/sysdeps/x86_64/multiarch/wcsnlen-evex.S
@@ -1,4 +1,8 @@ 
-#define STRLEN __wcsnlen_evex
+#ifndef WCSNLEN
+# define WCSNLEN	__wcsnlen_evex
+#endif
+
+#define STRLEN	WCSNLEN
 #define USE_AS_WCSLEN 1
 #define USE_AS_STRNLEN 1
 
diff --git a/sysdeps/x86_64/multiarch/wcsnlen-generic.c b/sysdeps/x86_64/multiarch/wcsnlen-generic.c
index 2d75da7709..8b466aac2f 100644
--- a/sysdeps/x86_64/multiarch/wcsnlen-generic.c
+++ b/sysdeps/x86_64/multiarch/wcsnlen-generic.c
@@ -16,13 +16,18 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
+#include <isa-level.h>
+
+#if ISA_SHOULD_BUILD (1)
 
-#if IS_IN (libc)
 # include <wchar.h>
 
-# define WCSNLEN __wcsnlen_generic
+# ifndef WCSNLEN
+#  define WCSNLEN __wcsnlen_generic
+# endif
 
 extern __typeof (wcsnlen) __wcsnlen_generic;
-#endif
 
-#include "wcsmbs/wcsnlen.c"
+# include "wcsmbs/wcsnlen.c"
+
+#endif
diff --git a/sysdeps/x86_64/multiarch/wcsnlen-sse4_1.S b/sysdeps/x86_64/multiarch/wcsnlen-sse4_1.S
index 17cdedc2a9..8f534102a2 100644
--- a/sysdeps/x86_64/multiarch/wcsnlen-sse4_1.S
+++ b/sysdeps/x86_64/multiarch/wcsnlen-sse4_1.S
@@ -1,6 +1,11 @@ 
+#ifndef WCSNLEN
+# define WCSNLEN	__wcsnlen_sse4_1
+# define OVERFLOW_STRLEN	__wcslen_sse4_1
+#endif
+
 #define AS_WCSLEN
 #define AS_STRNLEN
-#define STRLEN	__wcsnlen_sse4_1
+#define STRLEN	WCSNLEN
 #define SECTION(p)	p##.sse4.1
 
 #include "strlen-sse2.S"
diff --git a/sysdeps/x86_64/multiarch/wcsrchr-avx2.S b/sysdeps/x86_64/multiarch/wcsrchr-avx2.S
index cf8a239ab2..6eaf5e090b 100644
--- a/sysdeps/x86_64/multiarch/wcsrchr-avx2.S
+++ b/sysdeps/x86_64/multiarch/wcsrchr-avx2.S
@@ -1,3 +1,8 @@ 
-#define STRRCHR __wcsrchr_avx2
+#ifndef WCSRCHR
+# define WCSRCHR	__wcsrchr_avx2
+#endif
+
+#define STRRCHR	WCSRCHR
 #define USE_AS_WCSRCHR 1
+
 #include "strrchr-avx2.S"
diff --git a/sysdeps/x86_64/multiarch/wcsrchr-evex.S b/sysdeps/x86_64/multiarch/wcsrchr-evex.S
index c64602f7dc..e5c5fe3bf2 100644
--- a/sysdeps/x86_64/multiarch/wcsrchr-evex.S
+++ b/sysdeps/x86_64/multiarch/wcsrchr-evex.S
@@ -1,3 +1,7 @@ 
-#define STRRCHR __wcsrchr_evex
+#ifndef WCSRCHR
+# define WCSRCHR	__wcsrchr_evex
+#endif
+
+#define STRRCHR	WCSRCHR
 #define USE_AS_WCSRCHR 1
 #include "strrchr-evex.S"
diff --git a/sysdeps/x86_64/multiarch/wcsrchr-sse2.S b/sysdeps/x86_64/multiarch/wcsrchr-sse2.S
index d9259720f8..21388d900c 100644
--- a/sysdeps/x86_64/multiarch/wcsrchr-sse2.S
+++ b/sysdeps/x86_64/multiarch/wcsrchr-sse2.S
@@ -16,12 +16,11 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#if IS_IN (libc)
-# ifndef STRRCHR
-#  define STRRCHR	__wcsrchr_sse2
-# endif
+#ifndef WCSRCHR
+# define WCSRCHR	__wcsrchr_sse2
 #endif
 
+#define STRRCHR	WCSRCHR
 #define USE_AS_WCSRCHR	1
 #define NO_PMINU	1
 
diff --git a/sysdeps/x86_64/strcasecmp_l.S b/sysdeps/x86_64/strcasecmp_l.S
index 84fd7fdfd3..5afa7ea098 100644
--- a/sysdeps/x86_64/strcasecmp_l.S
+++ b/sysdeps/x86_64/strcasecmp_l.S
@@ -1,11 +1,35 @@ 
+/* strcasecmp_l dispatch for RTLD and non-multiarch build
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
 /* Symbols = __strcasecmp_l and __strcasecmp.  */
 
-#include "multiarch/strcasecmp_l-sse2.S"
+#define DEFAULT_IMPL_V1	"multiarch/strcasecmp_l-sse2.S"
+/* This may cause regressions on some processors that heavily prefer
+   aligned loads or have slow a implementation of the `pcmpstri`
+   instruction.  */
+#define DEFAULT_IMPL_V2	"multiarch/strcasecmp_l-sse4_2.S"
+#define DEFAULT_IMPL_V3	"multiarch/strcasecmp_l-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/strcasecmp_l-evex.S"
 
-libc_hidden_builtin_def (__strcasecmp_l)
+#include "isa-default-impl.h"
 
+libc_hidden_def (__strcasecmp_l)
 weak_alias (__strcasecmp_l, strcasecmp_l)
-libc_hidden_def (strcasecmp_l)
 
-weak_alias (__strcasecmp, strcasecmp)
 libc_hidden_def (__strcasecmp)
+weak_alias (__strcasecmp, strcasecmp)
diff --git a/sysdeps/x86_64/strchr-isa-default-impl.h b/sysdeps/x86_64/strchr-isa-default-impl.h
new file mode 100644
index 0000000000..0c8cbc6ffb
--- /dev/null
+++ b/sysdeps/x86_64/strchr-isa-default-impl.h
@@ -0,0 +1,28 @@ 
+/* Set default strchr impl based on ISA level.
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <isa-level.h>
+#if MINIMUM_X86_ISA_LEVEL == 1 || MINIMUM_X86_ISA_LEVEL == 2
+# define DEFAULT_STRCHR	__strchr_sse2
+#elif MINIMUM_X86_ISA_LEVEL == 3
+# define DEFAULT_STRCHR	__strchr_avx2
+#elif MINIMUM_X86_ISA_LEVEL == 4
+# define DEFAULT_STRCHR	__strchr_evex
+#else
+# error "Unknown default strchr implementation"
+#endif
diff --git a/sysdeps/x86_64/strchr.S b/sysdeps/x86_64/strchr.S
index 77c956c92c..1406c633e8 100644
--- a/sysdeps/x86_64/strchr.S
+++ b/sysdeps/x86_64/strchr.S
@@ -1,5 +1,4 @@ 
-/* strchr (str, ch) -- Return pointer to first occurrence of CH in STR.
-   For AMD x86-64.
+/* strchr dispatch for RTLD and non-multiarch build
    Copyright (C) 2009-2022 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -17,8 +16,13 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
+#define STRCHR	strchr
+
+#define DEFAULT_IMPL_V1	"multiarch/strchr-sse2.S"
+#define DEFAULT_IMPL_V3	"multiarch/strchr-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/strchr-evex.S"
+
+#include "isa-default-impl.h"
 
-#define STRCHR strchr
-#include "multiarch/strchr-sse2.S"
 weak_alias (strchr, index)
 libc_hidden_builtin_def (strchr)
diff --git a/sysdeps/x86_64/strchrnul.S b/sysdeps/x86_64/strchrnul.S
index 508e42db26..f1ef907296 100644
--- a/sysdeps/x86_64/strchrnul.S
+++ b/sysdeps/x86_64/strchrnul.S
@@ -1,6 +1,4 @@ 
-/* strchrnul (str, ch) -- Return pointer to first occurrence of CH in STR
-	or terminating NUL byte.
-   For AMD x86-64.
+/* strchrnul dispatch for RTLD and non-multiarch build
    Copyright (C) 2009-2022 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -18,7 +16,12 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#define STRCHR __strchrnul
-#include "multiarch/strchrnul-sse2.S"
+#define STRCHRNUL	__strchrnul
+
+#define DEFAULT_IMPL_V1	"multiarch/strchrnul-sse2.S"
+#define DEFAULT_IMPL_V3	"multiarch/strchrnul-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/strchrnul-evex.S"
+
+#include "isa-default-impl.h"
 
 weak_alias (__strchrnul, strchrnul)
diff --git a/sysdeps/x86_64/strcmp.S b/sysdeps/x86_64/strcmp.S
index 19e54bd3a7..7c3cf87a42 100644
--- a/sysdeps/x86_64/strcmp.S
+++ b/sysdeps/x86_64/strcmp.S
@@ -1,4 +1,4 @@ 
-/* Highly optimized version for x86-64.
+/* strcmp dispatch for RTLD and non-multiarch build
    Copyright (C) 1999-2022 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -18,5 +18,14 @@ 
 
 /* Symbol = strcmp.  */
 
-#include "multiarch/strcmp-sse2.S"
+#define DEFAULT_IMPL_V1	"multiarch/strcmp-sse2.S"
+/* strcmp-sse2-unaligned.S is often faster than strcmp-sse42.S and
+   doesn't have the drawback of using the `pcmpstri` instruction
+   which can be very slow on some CPUs.  */
+#define DEFAULT_IMPL_V2	"multiarch/strcmp-sse2-unaligned.S"
+#define DEFAULT_IMPL_V3	"multiarch/strcmp-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/strcmp-evex.S"
+
+#include "isa-default-impl.h"
+
 libc_hidden_builtin_def (strcmp)
diff --git a/sysdeps/x86_64/strlen.S b/sysdeps/x86_64/strlen.S
index c2f5674f8d..e7cb4b1680 100644
--- a/sysdeps/x86_64/strlen.S
+++ b/sysdeps/x86_64/strlen.S
@@ -1,4 +1,4 @@ 
-/* SSE2 version of strlen.
+/* strlen dispatch for RTLD and non-multiarch build
    Copyright (C) 2021-2022 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -17,6 +17,11 @@ 
    <https://www.gnu.org/licenses/>.  */
 
 #define STRLEN	strlen
-#include "multiarch/strlen-sse2.S"
+
+#define DEFAULT_IMPL_V1	"multiarch/strlen-sse2.S"
+#define DEFAULT_IMPL_V3	"multiarch/strlen-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/strlen-evex.S"
+
+#include "isa-default-impl.h"
 
 libc_hidden_builtin_def (strlen)
diff --git a/sysdeps/x86_64/strncase_l.S b/sysdeps/x86_64/strncase_l.S
index 3780fc50b1..de28ecf5d4 100644
--- a/sysdeps/x86_64/strncase_l.S
+++ b/sysdeps/x86_64/strncase_l.S
@@ -1,11 +1,35 @@ 
+/* strcasecmp_l dispatch for RTLD and non-multiarch build
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
 /* Symbols = __strncasecmp_l and __strncasecmp.  */
 
-#include "multiarch/strncase_l-sse2.S"
+#define DEFAULT_IMPL_V1	"multiarch/strncase_l-sse2.S"
+/* This may cause regressions on some processors that heavily prefer
+   aligned loads or have slow a implementation of the `pcmpstri`
+   instruction.  */
+#define DEFAULT_IMPL_V2	"multiarch/strncase_l-sse4_2.S"
+#define DEFAULT_IMPL_V3	"multiarch/strncase_l-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/strncase_l-evex.S"
 
-libc_hidden_builtin_def (__strncasecmp_l)
+#include "isa-default-impl.h"
 
+libc_hidden_def (__strncasecmp_l)
 weak_alias (__strncasecmp_l, strncasecmp_l)
-libc_hidden_def (strncasecmp_l)
 
-weak_alias (__strncasecmp, strncasecmp)
 libc_hidden_def (__strncasecmp)
+weak_alias (__strncasecmp, strncasecmp)
diff --git a/sysdeps/x86_64/strncmp.S b/sysdeps/x86_64/strncmp.S
index 13d9e82ee2..afb251d9fe 100644
--- a/sysdeps/x86_64/strncmp.S
+++ b/sysdeps/x86_64/strncmp.S
@@ -1,4 +1,31 @@ 
+/* strncmp dispatch for RTLD and non-multiarch build
+   Copyright (C) 1999-2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
 /* Symbol = strncmp.  */
 
-#include "multiarch/strncmp-sse2.S"
+#define DEFAULT_IMPL_V1	"multiarch/strncmp-sse2.S"
+/* This may cause regressions on some processors that heavily prefer
+   aligned loads or have slow a implementation of the `pcmpstri`
+   instruction.  */
+#define DEFAULT_IMPL_V2	"multiarch/strncmp-sse4_2.S"
+#define DEFAULT_IMPL_V3	"multiarch/strncmp-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/strncmp-evex.S"
+
+#include "isa-default-impl.h"
+
 libc_hidden_builtin_def (strncmp)
diff --git a/sysdeps/x86_64/strnlen.S b/sysdeps/x86_64/strnlen.S
index 174970d58f..b2c2149e07 100644
--- a/sysdeps/x86_64/strnlen.S
+++ b/sysdeps/x86_64/strnlen.S
@@ -1,6 +1,29 @@ 
-#define STRLEN __strnlen
-#include "multiarch/strnlen-sse2.S"
+/* strnlen dispatch for RTLD and non-multiarch build
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
 
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#define STRNLEN	__strnlen
+
+#define DEFAULT_IMPL_V1	"multiarch/strnlen-sse2.S"
+#define DEFAULT_IMPL_V3	"multiarch/strnlen-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/strnlen-evex.S"
+
+#include "isa-default-impl.h"
+
+weak_alias (__strnlen, strnlen)
 libc_hidden_def (__strnlen)
-weak_alias (__strnlen, strnlen);
-libc_hidden_builtin_def (strnlen)
+libc_hidden_def (strnlen)
diff --git a/sysdeps/x86_64/strrchr.S b/sysdeps/x86_64/strrchr.S
index f39da60454..493d370a28 100644
--- a/sysdeps/x86_64/strrchr.S
+++ b/sysdeps/x86_64/strrchr.S
@@ -1,4 +1,4 @@ 
-/* strrchr (str, ch) -- Return pointer to last occurrence of CH in STR.
+/* strrchr dispatch for RTLD and non-multiarch build
    Copyright (C) 2013-2022 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -17,6 +17,12 @@ 
    <https://www.gnu.org/licenses/>.  */
 
 #define STRRCHR	strrchr
-#include "multiarch/strrchr-sse2.S"
+
+#define DEFAULT_IMPL_V1	"multiarch/strrchr-sse2.S"
+#define DEFAULT_IMPL_V3	"multiarch/strrchr-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/strrchr-evex.S"
+
+#include "isa-default-impl.h"
+
 weak_alias (strrchr, rindex)
 libc_hidden_builtin_def (strrchr)
diff --git a/sysdeps/x86_64/wcschr.S b/sysdeps/x86_64/wcschr.S
index 80b12c4286..01a432b899 100644
--- a/sysdeps/x86_64/wcschr.S
+++ b/sysdeps/x86_64/wcschr.S
@@ -1,4 +1,4 @@ 
-/* wcschr with SSSE3
+/* wcschr dispatch for RTLD and non-multiarch build
    Copyright (C) 2011-2022 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -16,9 +16,14 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-
 #define WCSCHR	__wcschr
-#include "multiarch/wcschr-sse2.S"
-libc_hidden_def(__wcschr)
+
+#define DEFAULT_IMPL_V1	"multiarch/wcschr-sse2.S"
+#define DEFAULT_IMPL_V3	"multiarch/wcschr-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/wcschr-evex.S"
+
+#include "isa-default-impl.h"
+
+libc_hidden_def (__wcschr)
 weak_alias (__wcschr, wcschr)
 libc_hidden_weak (wcschr)
diff --git a/sysdeps/x86_64/wcscmp.S b/sysdeps/x86_64/wcscmp.S
index e04cdbf5fe..5d30545fb6 100644
--- a/sysdeps/x86_64/wcscmp.S
+++ b/sysdeps/x86_64/wcscmp.S
@@ -1,4 +1,4 @@ 
-/* Optimized wcscmp for x86-64 with SSE2.
+/* strlen dispatch for RTLD and non-multiarch build
    Copyright (C) 2011-2022 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -18,6 +18,11 @@ 
 
 /* Symbol = __wcscmp.  */
 
-#include "multiarch/wcscmp-sse2.S"
+#define DEFAULT_IMPL_V1	"multiarch/wcscmp-sse2.S"
+#define DEFAULT_IMPL_V3	"multiarch/wcscmp-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/wcscmp-evex.S"
+
+#include "isa-default-impl.h"
+
 libc_hidden_def (__wcscmp)
 weak_alias (__wcscmp, wcscmp)
diff --git a/sysdeps/x86_64/wcslen.S b/sysdeps/x86_64/wcslen.S
index 588a0fbe01..e4e25b5353 100644
--- a/sysdeps/x86_64/wcslen.S
+++ b/sysdeps/x86_64/wcslen.S
@@ -1,4 +1,4 @@ 
-/* Optimized wcslen for x86-64 with SSE2.
+/* wcslen dispatch for RTLD and non-multiarch build
    Copyright (C) 2011-2022 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -17,5 +17,18 @@ 
    <https://www.gnu.org/licenses/>.  */
 
 #define WCSLEN	__wcslen
-#include "multiarch/wcslen-sse2.S"
-weak_alias(__wcslen, wcslen)
+
+#define DEFAULT_IMPL_V1	"multiarch/wcslen-sse2.S"
+#define DEFAULT_IMPL_V2	"multiarch/wcslen-sse4_1.S"
+#define DEFAULT_IMPL_V3	"multiarch/wcslen-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/wcslen-evex.S"
+
+#include "isa-default-impl.h"
+
+weak_alias (__wcslen, wcslen)
+
+#if MINIMUM_X86_ISA_LEVEL == 2 && !IS_IN (rtld)
+/* Hidden def so it can be used as overflow fallback in
+   wcsnlen-sse4_1.S.  */
+libc_hidden_def (__wcslen)
+#endif
diff --git a/sysdeps/x86_64/wcsncmp-generic.c b/sysdeps/x86_64/wcsncmp-generic.c
new file mode 100644
index 0000000000..493a6f9b9b
--- /dev/null
+++ b/sysdeps/x86_64/wcsncmp-generic.c
@@ -0,0 +1,29 @@ 
+/* wcsncmp dispatch for RTLD and non-multiarch .c ISA level 1 build.
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+/* wcsncmp non-multiarch build is split into two files,
+   wcsncmp-generic.c and wcsncmp.S. The wcsncmp-generic.c build is for
+   ISA level <= 1 and just uses wcsmbs/wcsncmp.c.  This must be split
+   into two files because we cannot include C code from assembly or
+   vice versa.  */
+
+#include <isa-level.h>
+
+#if MINIMUM_X86_ISA_LEVEL <= 2
+# include "wcsmbs/wcsncmp.c"
+#endif
diff --git a/sysdeps/x86_64/wcsncmp.S b/sysdeps/x86_64/wcsncmp.S
new file mode 100644
index 0000000000..14f9a1341e
--- /dev/null
+++ b/sysdeps/x86_64/wcsncmp.S
@@ -0,0 +1,40 @@ 
+/* wcsncmp dispatch for RTLD and non-multiarch .c files
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+/* wcsncmp non-multiarch build is split into two files,
+   wcsncmp-generic.c and wcsncmp.S. The wcsncmp.S build is for
+   ISA level >= 3 uses the optimized assembly implementations in
+   multiarch/wcsncmp*.S.  This must be split into two files because
+   we cannot include C code from assembly or vice versa.  */
+
+#include <isa-level.h>
+
+#if MINIMUM_X86_ISA_LEVEL >= 3
+
+/* Symbol = wcsncmp.  */
+
+# define DEFAULT_IMPL_V3	"multiarch/wcsncmp-avx2.S"
+# define DEFAULT_IMPL_V4	"multiarch/wcsncmp-evex.S"
+
+/* isa-default-impl.h expects DEFAULT_IMPL_V1 to be defined but it
+   should never be used from here.  */
+# define DEFAULT_IMPL_V1	"ERROR -- Invalid ISA IMPL"
+
+# include "isa-default-impl.h"
+
+#endif
diff --git a/sysdeps/x86_64/wcsnlen-generic.c b/sysdeps/x86_64/wcsnlen-generic.c
new file mode 100644
index 0000000000..ec66511589
--- /dev/null
+++ b/sysdeps/x86_64/wcsnlen-generic.c
@@ -0,0 +1,29 @@ 
+/* wcsnlen dispatch for RTLD and non-multiarch .c ISA level 1 build.
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+/* wcsnlen non-multiarch build is split into two files,
+   wcsnlen-generic.c and wcsnlen.S. The wcsnlen-generic.c build is for
+   ISA level <= 1 and just uses wcsmbs/wcsnlen.c.  This must be split
+   into two files because we cannot include C code from assembly or
+   vice versa.  */
+
+#include <isa-level.h>
+
+#if MINIMUM_X86_ISA_LEVEL <= 1
+# include "wcsmbs/wcsnlen.c"
+#endif
diff --git a/sysdeps/x86_64/wcsnlen.S b/sysdeps/x86_64/wcsnlen.S
new file mode 100644
index 0000000000..b30b3f0785
--- /dev/null
+++ b/sysdeps/x86_64/wcsnlen.S
@@ -0,0 +1,49 @@ 
+/* wcsnlen dispatch for RTLD and non-multiarch .c files
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+/* wcsnlen non-multiarch build is split into two files,
+   wcsnlen-generic.c and wcsnlen.S. The wcsnlen.S build is for
+   ISA level >= 2 uses the optimized assembly implementations in
+   multiarch/wcsnlen*.S.  This must be split into two files because
+   we cannot include C code from assembly or vice versa.  */
+
+#include <isa-level.h>
+
+#if MINIMUM_X86_ISA_LEVEL >= 2
+
+# define WCSNLEN	__wcsnlen
+/* This symbol must stay linked to the name in wcslen.S.  */
+#if IS_IN (rtld)
+# define OVERFLOW_STRLEN	__wcslen
+#else
+# define OVERFLOW_STRLEN	HIDDEN_JUMPTARGET (__wcslen)
+#endif
+
+# define DEFAULT_IMPL_V2	"multiarch/wcsnlen-sse4_1.S"
+# define DEFAULT_IMPL_V3	"multiarch/wcsnlen-avx2.S"
+# define DEFAULT_IMPL_V4	"multiarch/wcsnlen-evex.S"
+
+/* isa-default-impl.h expects DEFAULT_IMPL_V1 to be defined but it
+   should never be used from here.  */
+# define DEFAULT_IMPL_V1	"ERROR -- Invalid ISA IMPL"
+
+# include "isa-default-impl.h"
+
+weak_alias (__wcsnlen, wcsnlen)
+libc_hidden_def (__wcsnlen)
+#endif
diff --git a/sysdeps/x86_64/wcsrchr.S b/sysdeps/x86_64/wcsrchr.S
index 1d4b1eb21c..abf828b458 100644
--- a/sysdeps/x86_64/wcsrchr.S
+++ b/sysdeps/x86_64/wcsrchr.S
@@ -1,4 +1,4 @@ 
-/* wcsrchr optimized with SSE2.
+/* wcsrchr dispatch for RTLD and non-multiarch build
    Copyright (C) 2011-2022 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -16,5 +16,10 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#define STRRCHR	wcsrchr
-#include "multiarch/wcsrchr-sse2.S"
+#define WCSRCHR	wcsrchr
+
+#define DEFAULT_IMPL_V1	"multiarch/wcsrchr-sse2.S"
+#define DEFAULT_IMPL_V3	"multiarch/wcsrchr-avx2.S"
+#define DEFAULT_IMPL_V4	"multiarch/wcsrchr-evex.S"
+
+#include "isa-default-impl.h"