x86: Rename generic functions with unique postfix for clarity

No functions are changed. It just renames generic implementations from
'{func}_sse2' to '{func}_generic'. This is just because the postfix
"_sse2" was overloaded and was used for files that had hand-optimized
sse2 assembly implementations and files that just redirected back
to the generic implementation.

Full xcheck passed on x86_64.

1 files changed, 163 insertions, 0 deletions

diff --git a/sysdeps/x86_64/multiarch/strcspn-sse4.c b/sysdeps/x86_64/multiarch/strcspn-sse4.c
new file mode 100644
index 0000000000..59f64f9fe8
--- /dev/null
+++ b/sysdeps/x86_64/multiarch/strcspn-sse4.c
@@ -0,0 +1,163 @@
+/* strcspn with SSE4.2 intrinsics
+   Copyright (C) 2009-2022 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 <nmmintrin.h>
+#include <string.h>
+#include "varshift.h"
+
+/* We use 0x2:
+	_SIDD_SBYTE_OPS
+	| _SIDD_CMP_EQUAL_ANY
+	| _SIDD_POSITIVE_POLARITY
+	| _SIDD_LEAST_SIGNIFICANT
+   on pcmpistri to compare xmm/mem128
+
+   0 1 2 3 4 5 6 7 8 9 A B C D E F
+   X X X X X X X X X X X X X X X X
+
+   against xmm
+
+   0 1 2 3 4 5 6 7 8 9 A B C D E F
+   A A A A A A A A A A A A A A A A
+
+   to find out if the first 16byte data element has any byte A and
+   the offset of the first byte.  There are 3 cases:
+
+   1. The first 16byte data element has the byte A at the offset X.
+   2. The first 16byte data element has EOS and doesn't have the byte A.
+   3. The first 16byte data element is valid and doesn't have the byte A.
+
+   Here is the table of ECX, CFlag, ZFlag and SFlag for 2 cases:
+
+    1		 X	  1	 0/1	  0
+    2		16	  0	  1	  0
+    3		16	  0	  0	  0
+
+   We exit from the loop for cases 1 and 2 with jbe which branches
+   when either CFlag or ZFlag is 1.  If CFlag == 1, ECX has the offset
+   X for case 1.  */
+
+#ifndef STRCSPN_GENERIC
+# define STRCSPN_GENERIC __strcspn_generic
+# define STRCSPN_SSE42 __strcspn_sse42
+#endif
+
+#ifdef USE_AS_STRPBRK
+# define RETURN(val1, val2) return val1
+#else
+# define RETURN(val1, val2) return val2
+#endif
+
+extern
+#ifdef USE_AS_STRPBRK
+char *
+#else
+size_t
+#endif
+STRCSPN_GENERIC (const char *, const char *) attribute_hidden;
+
+
+#ifdef USE_AS_STRPBRK
+char *
+#else
+size_t
+#endif
+__attribute__ ((section (".text.sse4.2")))
+STRCSPN_SSE42 (const char *s, const char *a)
+{
+  if (*a == 0)
+    RETURN (NULL, strlen (s));
+
+  const char *aligned;
+  __m128i mask, maskz, zero;
+  unsigned int maskz_bits;
+  unsigned int offset = (unsigned int) ((size_t) a & 15);
+  zero = _mm_set1_epi8 (0);
+  if (offset != 0)
+    {
+      /* Load masks.  */
+      aligned = (const char *) ((size_t) a & -16L);
+      __m128i mask0 = _mm_load_si128 ((__m128i *) aligned);
+      maskz = _mm_cmpeq_epi8 (mask0, zero);
+
+      /* Find where the NULL terminator is.  */
+      maskz_bits = _mm_movemask_epi8 (maskz) >> offset;
+      if (maskz_bits != 0)
+        {
+          mask = __m128i_shift_right (mask0, offset);
+          offset = (unsigned int) ((size_t) s & 15);
+          if (offset)
+            goto start_unaligned;
+
+          aligned = s;
+          goto start_loop;
+        }
+    }
+
+  /* A is aligned.  */
+  mask = _mm_loadu_si128 ((__m128i *) a);
+  /* Find where the NULL terminator is.  */
+  maskz = _mm_cmpeq_epi8 (mask, zero);
+  maskz_bits = _mm_movemask_epi8 (maskz);
+  if (maskz_bits == 0)
+    {
+      /* There is no NULL terminator.  Don't use SSE4.2 if the length
+         of A > 16.  */
+      if (a[16] != 0)
+        return STRCSPN_GENERIC (s, a);
+    }
+
+  aligned = s;
+  offset = (unsigned int) ((size_t) s & 15);
+  if (offset != 0)
+    {
+    start_unaligned:
+      /* Check partial string.  */
+      aligned = (const char *) ((size_t) s & -16L);
+      __m128i value = _mm_load_si128 ((__m128i *) aligned);
+
+      value = __m128i_shift_right (value, offset);
+
+      unsigned int length = _mm_cmpistri (mask, value, 0x2);
+      /* No need to check ZFlag since ZFlag is always 1.  */
+      unsigned int cflag = _mm_cmpistrc (mask, value, 0x2);
+      if (cflag)
+	RETURN ((char *) (s + length), length);
+      /* Find where the NULL terminator is.  */
+      unsigned int index = _mm_cmpistri (value, value, 0x3a);
+      if (index < 16 - offset)
+	RETURN (NULL, index);
+      aligned += 16;
+    }
+
+start_loop:
+  while (1)
+    {
+      __m128i value = _mm_load_si128 ((__m128i *) aligned);
+      unsigned int index = _mm_cmpistri (mask, value, 0x2);
+      unsigned int cflag = _mm_cmpistrc (mask, value, 0x2);
+      unsigned int zflag = _mm_cmpistrz (mask, value, 0x2);
+      if (cflag)
+	RETURN ((char *) (aligned + index), (size_t) (aligned + index - s));
+      if (zflag)
+	RETURN (NULL,
+		/* Find where the NULL terminator is.  */
+		(size_t) (aligned + _mm_cmpistri (value, value, 0x3a) - s));
+      aligned += 16;
+    }
+}