x86-64: Update strlen.S to support wcslen/wcsnlen

The difference between strlen and wcslen is byte vs int.  We can
replace pminub and pcmpeqb with pminud and pcmpeqd to turn strlen
into wcslen.

	* sysdeps/x86_64/strlen.S (PMINU): New.
	(PCMPEQ): Likewise.
	(SHIFT_RETURN): Likewise.
	(FIND_ZERO): Replace pcmpeqb with PCMPEQ.
	(strlen): Add SHIFT_RETURN before ret.  Replace pcmpeqb and
	pminub with PCMPEQ and PMINU.
	* sysdeps/x86_64/wcsnlen.S: New file.

diff --git a/ChangeLog b/ChangeLog
index 1549eb64226026b59dd2c014f3221faa2e89feae..5a70bf18e28beb5e64907c274d6116c709d5799a 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2017-06-05  H.J. Lu  <hongjiu.lu@intel.com>
+
+       * sysdeps/x86_64/strlen.S (PMINU): New.
+       (PCMPEQ): Likewise.
+       (SHIFT_RETURN): Likewise.
+       (FIND_ZERO): Replace pcmpeqb with PCMPEQ.
+       (strlen): Add SHIFT_RETURN before ret.  Replace pcmpeqb and
+       pminub with PCMPEQ and PMINU.
+       * sysdeps/x86_64/wcsnlen.S: New file.
+
 2017-06-05  H.J. Lu  <hongjiu.lu@intel.com>
 
        * sysdeps/x86_64/memrchr.S (__memrchr): Use 32-bit registers for

diff --git a/sysdeps/x86_64/strlen.S b/sysdeps/x86_64/strlen.S
index 5896e6b9ee4ba092a5479ea7b6bfd0b0e2e8210d..b5ab117c79e1e26c6d43535d74e63515c258deb0 100644 (file)
--- a/sysdeps/x86_64/strlen.S
+++ b/sysdeps/x86_64/strlen.S
@@ -1,4 +1,4 @@
-/* SSE2 version of strlen.
+/* SSE2 version of strlen/wcslen.
    Copyright (C) 2012-2017 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -18,6 +18,16 @@
 
 #include <sysdep.h>
 
+#ifdef AS_WCSLEN
+# define PMINU         pminud
+# define PCMPEQ                pcmpeqd
+# define SHIFT_RETURN  shrq $2, %rax
+#else
+# define PMINU         pminub
+# define PCMPEQ                pcmpeqb
+# define SHIFT_RETURN
+#endif
+
 /* Long lived register in strlen(s), strnlen(s, n) are:
 
        %xmm3 - zero
@@ -32,10 +42,10 @@ ENTRY(strlen)
 
 /* Test 64 bytes from %rax for zero. Save result as bitmask in %rdx.  */
 #define FIND_ZERO      \
-       pcmpeqb (%rax), %xmm0;  \
-       pcmpeqb 16(%rax), %xmm1;        \
-       pcmpeqb 32(%rax), %xmm2;        \
-       pcmpeqb 48(%rax), %xmm3;        \
+       PCMPEQ  (%rax), %xmm0;  \
+       PCMPEQ  16(%rax), %xmm1;        \
+       PCMPEQ  32(%rax), %xmm2;        \
+       PCMPEQ  48(%rax), %xmm3;        \
        pmovmskb        %xmm0, %esi;    \
        pmovmskb        %xmm1, %edx;    \
        pmovmskb        %xmm2, %r8d;    \
@@ -54,6 +64,9 @@ ENTRY(strlen)
        xor     %rax, %rax
        ret
 L(n_nonzero):
+# ifdef AS_WCSLEN
+       shlq    $2, %rsi
+# endif
 
 /* Initialize long lived registers.  */
 
@@ -96,6 +109,7 @@ L(n_nonzero):
        test    %rdx, %rdx;     \
        je      L(lab); \
        bsfq    %rdx, %rax;     \
+       SHIFT_RETURN;           \
        ret
 
 #ifdef AS_STRNLEN
@@ -104,19 +118,20 @@ L(n_nonzero):
 #else
        /* Test first 16 bytes unaligned.  */
        movdqu  (%rax), %xmm4
-       pcmpeqb %xmm0, %xmm4
+       PCMPEQ  %xmm0, %xmm4
        pmovmskb        %xmm4, %edx
        test    %edx, %edx
        je      L(next48_bytes)
        bsf     %edx, %eax /* If eax is zeroed 16bit bsf can be used.  */
+       SHIFT_RETURN
        ret
 
 L(next48_bytes):
 /* Same as FIND_ZERO except we do not check first 16 bytes.  */
        andq    $-16, %rax
-       pcmpeqb 16(%rax), %xmm1
-       pcmpeqb 32(%rax), %xmm2
-       pcmpeqb 48(%rax), %xmm3
+       PCMPEQ 16(%rax), %xmm1
+       PCMPEQ 32(%rax), %xmm2
+       PCMPEQ 48(%rax), %xmm3
        pmovmskb        %xmm1, %edx
        pmovmskb        %xmm2, %r8d
        pmovmskb        %xmm3, %ecx
@@ -145,6 +160,7 @@ L(strnlen_ret):
        test    %rdx, %rdx
        je      L(loop_init)
        bsfq    %rdx, %rax
+       SHIFT_RETURN
        ret
 #endif
        .p2align 4
@@ -161,10 +177,10 @@ L(loop):
        je      L(exit_end)
 
        movdqa  (%rax), %xmm0
-       pminub  16(%rax), %xmm0
-       pminub  32(%rax), %xmm0
-       pminub  48(%rax), %xmm0
-       pcmpeqb %xmm3, %xmm0
+       PMINU   16(%rax), %xmm0
+       PMINU   32(%rax), %xmm0
+       PMINU   48(%rax), %xmm0
+       PCMPEQ  %xmm3, %xmm0
        pmovmskb        %xmm0, %edx
        testl   %edx, %edx
        jne     L(exit)
@@ -182,6 +198,7 @@ L(first):
        bsfq    %rdx, %rdx
        addq    %rdx, %rax
        subq    %rdi, %rax
+       SHIFT_RETURN
        ret
 
        .p2align 4
@@ -192,6 +209,7 @@ L(exit):
        bsfq    %rdx, %rdx
        addq    %rdx, %rax
        subq    %rdi, %rax
+       SHIFT_RETURN
        ret
 
 #else
@@ -201,10 +219,10 @@ L(exit):
 L(loop):
 
        movdqa  64(%rax), %xmm0
-       pminub  80(%rax), %xmm0
-       pminub  96(%rax), %xmm0
-       pminub  112(%rax), %xmm0
-       pcmpeqb %xmm3, %xmm0
+       PMINU   80(%rax), %xmm0
+       PMINU   96(%rax), %xmm0
+       PMINU   112(%rax), %xmm0
+       PCMPEQ  %xmm3, %xmm0
        pmovmskb        %xmm0, %edx
        testl   %edx, %edx
        jne     L(exit64)
@@ -212,10 +230,10 @@ L(loop):
        subq    $-128, %rax
 
        movdqa  (%rax), %xmm0
-       pminub  16(%rax), %xmm0
-       pminub  32(%rax), %xmm0
-       pminub  48(%rax), %xmm0
-       pcmpeqb %xmm3, %xmm0
+       PMINU   16(%rax), %xmm0
+       PMINU   32(%rax), %xmm0
+       PMINU   48(%rax), %xmm0
+       PCMPEQ  %xmm3, %xmm0
        pmovmskb        %xmm0, %edx
        testl   %edx, %edx
        jne     L(exit0)
@@ -231,6 +249,7 @@ L(exit0):
        bsfq    %rdx, %rdx
        addq    %rdx, %rax
        subq    %rdi, %rax
+       SHIFT_RETURN
        ret
 
 #endif

diff --git a/sysdeps/x86_64/wcsnlen.S b/sysdeps/x86_64/wcsnlen.S
new file mode 100644 (file)
index 0000000..968bb69
--- /dev/null
+++ b/sysdeps/x86_64/wcsnlen.S
@@ -0,0 +1,7 @@
+#define AS_WCSLEN
+#define AS_STRNLEN
+#define strlen __wcsnlen
+
+#include "strlen.S"
+
+weak_alias(__wcsnlen, wcsnlen)