diff mbox series

Don't allow mask/sse/mmx mov in TLS code sequences.

Message ID 20211118071825.1796-1-hongtao.liu@intel.com
State New
Headers show
Series Don't allow mask/sse/mmx mov in TLS code sequences. | expand

Commit Message

liuhongt Nov. 18, 2021, 7:18 a.m. UTC
As change in assembler, refer to [1], this patch disallow mask/sse/mmx
mov in TLS code sequences which require integer MOV instructions.

[1] https://sourceware.org/git/?p=binutils-gdb.git;a=patch;h=d7e3e627027fcf37d63e284144fe27ff4eba36b5

Bootstrapped and regtested on x86_64-pc-linux-gnu{-m32,}.
Ok for trunk and GCC11 upstream branch?

gcc/ChangeLog:

	PR target/103275
	* config/i386/i386-protos.h (ix86_notls_memory): Declare.
	* config/i386/i386.c (ix86_notls_memory): New function.
	* config/i386/i386.md (*movsi_internal): Don't allow
	mask/sse/mmx move in TLS code sequences.
	(*movdi_internal): Ditto.

gcc/testsuite/ChangeLog:

	* gcc.target/i386/pr103275.c: New test.
---
 gcc/config/i386/constraints.md           |   5 +
 gcc/config/i386/i386-protos.h            |   1 +
 gcc/config/i386/i386.c                   |  34 ++++++
 gcc/config/i386/i386.md                  |  18 +--
 gcc/testsuite/gcc.target/i386/pr103275.c | 148 +++++++++++++++++++++++
 5 files changed, 197 insertions(+), 9 deletions(-)
 create mode 100644 gcc/testsuite/gcc.target/i386/pr103275.c

Comments

Uros Bizjak Nov. 18, 2021, 8:19 a.m. UTC | #1
On Thu, Nov 18, 2021 at 8:18 AM liuhongt <hongtao.liu@intel.com> wrote:
>
> As change in assembler, refer to [1], this patch disallow mask/sse/mmx
> mov in TLS code sequences which require integer MOV instructions.
>
> [1] https://sourceware.org/git/?p=binutils-gdb.git;a=patch;h=d7e3e627027fcf37d63e284144fe27ff4eba36b5
>
> Bootstrapped and regtested on x86_64-pc-linux-gnu{-m32,}.
> Ok for trunk and GCC11 upstream branch?
>
> gcc/ChangeLog:
>
>         PR target/103275
>         * config/i386/i386-protos.h (ix86_notls_memory): Declare.
>         * config/i386/i386.c (ix86_notls_memory): New function.
>         * config/i386/i386.md (*movsi_internal): Don't allow
>         mask/sse/mmx move in TLS code sequences.
>         (*movdi_internal): Ditto.
>
> gcc/testsuite/ChangeLog:
>
>         * gcc.target/i386/pr103275.c: New test.
> ---
>  gcc/config/i386/constraints.md           |   5 +
>  gcc/config/i386/i386-protos.h            |   1 +
>  gcc/config/i386/i386.c                   |  34 ++++++
>  gcc/config/i386/i386.md                  |  18 +--
>  gcc/testsuite/gcc.target/i386/pr103275.c | 148 +++++++++++++++++++++++
>  5 files changed, 197 insertions(+), 9 deletions(-)
>  create mode 100644 gcc/testsuite/gcc.target/i386/pr103275.c
>
> diff --git a/gcc/config/i386/constraints.md b/gcc/config/i386/constraints.md
> index 87cceac4cfb..489c76164a1 100644
> --- a/gcc/config/i386/constraints.md
> +++ b/gcc/config/i386/constraints.md
> @@ -186,6 +186,11 @@ (define_special_memory_constraint "Bc"
>    (and (match_operand 0 "memory_operand")
>         (match_test "constant_address_p (XEXP (op, 0))")))
>
> +(define_special_memory_constraint "Bk"
> +  "@internal notls memory operand."
> +  (and (match_operand 0 "memory_operand")
> +       (match_test "ix86_notls_memory (op)")))

Why is the above declared as a special memory constraint? Also the
predicate comment is missing and the description should say something
like:

@internal TLS address that allows insn using non-integer registers

>  (define_special_memory_constraint "Bn"
>    "@internal Memory operand without REX prefix."
>    (match_operand 0 "norex_memory_operand"))
> diff --git a/gcc/config/i386/i386-protos.h b/gcc/config/i386/i386-protos.h
> index 7e05510c679..1fb09be8b7e 100644
> --- a/gcc/config/i386/i386-protos.h
> +++ b/gcc/config/i386/i386-protos.h
> @@ -243,6 +243,7 @@ extern unsigned int ix86_get_callcvt (const_tree);
>  #endif
>
>  extern rtx ix86_tls_module_base (void);
> +extern bool ix86_notls_memory (rtx);
>  extern bool ix86_tls_address_pattern_p (rtx);
>  extern rtx ix86_rewrite_tls_address (rtx);
>
> diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
> index c246c8736f5..f1b7f57b0ca 100644
> --- a/gcc/config/i386/i386.c
> +++ b/gcc/config/i386/i386.c
> @@ -11628,6 +11628,40 @@ legitimize_tls_address (rtx x, enum tls_model model, bool for_mov)
>    return dest;
>  }
>
> +/* Return true if it's not tls memory,
> +   NB: it's different from ix86_tls_address_pattern_p since it also matchs
> +   gottpoff/gotntpoff.
> +   It's used to prevent KMOV/VMOV in TLS code sequences which require integer
> +   MOV instructions, refer to PR103275.  */
> +bool
> +ix86_notls_memory (rtx mem)

I think it is better to avoid negative logic. So, something like

Return true if the TLS address requires insn using integer registers.

bool
ix86_gpr_tls_address_pattern_p

(and use not in the predicate)

> +{
> +  gcc_assert (MEM_P (mem));
> +
> +  rtx addr = XEXP (mem, 0);
> +  subrtx_var_iterator::array_type array;
> +  FOR_EACH_SUBRTX_VAR (iter, array, addr, ALL)
> +    {
> +      rtx op = *iter;
> +      if (GET_CODE (op) == UNSPEC)
> +       switch (XINT (op, 1))
> +         {
> +         case UNSPEC_GOTNTPOFF:
> +           return false;
> +         case UNSPEC_TPOFF:
> +           if (!TARGET_64BIT)
> +             return false;
> +           break;
> +         default:
> +           break;
> +         }
> +      /* Should iter.skip_subrtxes ();
> +        if there's no inner UNSPEC in addr???.  */

You should figure the above before submitting the patch.

> +    }
> +
> +  return true;
> +}
> +
>  /* Return true if OP refers to a TLS address.  */
>  bool
>  ix86_tls_address_pattern_p (rtx op)
> diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
> index 7b2de60706d..9feba81974b 100644
> --- a/gcc/config/i386/i386.md
> +++ b/gcc/config/i386/i386.md
> @@ -2164,9 +2164,9 @@ (define_split
>
>  (define_insn "*movdi_internal"
>    [(set (match_operand:DI 0 "nonimmediate_operand"
> -    "=r  ,o  ,r,r  ,r,m ,*y,*y,?*y,?m,?r,?*y,*v,*v,*v,m ,m,?r ,?*Yd,?r,?*v,?*y,?*x,*k,*k ,*r,*m,*k")
> +    "=r  ,o  ,r,r  ,r,m ,*y,*y,?*y,?m,?r,?*y,*v,*v,*v,m ,m,?r ,?*Yd,?r,?*v,?*y,?*x,*k,*k,*k ,*r,*m,*k")
>         (match_operand:DI 1 "general_operand"
> -    "riFo,riF,Z,rem,i,re,C ,*y,m  ,*y,*y,r  ,C ,*v,m ,*v,v,*Yd,r   ,*v,r  ,*x ,*y ,*r,*km,*k,*k,CBC"))]
> +    "riFo,riF,Z,rem,i,re,C ,*y,Bk ,*y,*y,r  ,C ,*v,Bk,*v,v,*Yd,r   ,*v,r  ,*x ,*y ,*r,*k,*Bk,*k,*k,CBC"))]
>    "!(MEM_P (operands[0]) && MEM_P (operands[1]))
>     && ix86_hardreg_mov_ok (operands[0], operands[1])"
>  {
> @@ -2228,7 +2228,7 @@ (define_insn "*movdi_internal"
>    [(set (attr "isa")
>       (cond [(eq_attr "alternative" "0,1,17,18")
>               (const_string "nox64")
> -           (eq_attr "alternative" "2,3,4,5,10,11,23,25")
> +           (eq_attr "alternative" "2,3,4,5,10,11,23,26")
>               (const_string "x64")
>             (eq_attr "alternative" "19,20")
>               (const_string "x64_sse2")
> @@ -2249,9 +2249,9 @@ (define_insn "*movdi_internal"
>               (const_string "ssemov")
>             (eq_attr "alternative" "21,22")
>               (const_string "ssecvt")
> -           (eq_attr "alternative" "23,24,25,26")
> +           (eq_attr "alternative" "23,24,25,26,27")
>               (const_string "mskmov")
> -           (eq_attr "alternative" "27")
> +           (eq_attr "alternative" "28")
>               (const_string "msklog")
>             (and (match_operand 0 "register_operand")
>                  (match_operand 1 "pic_32bit_operand"))
> @@ -2385,9 +2385,9 @@ (define_peephole2
>
>  (define_insn "*movsi_internal"
>    [(set (match_operand:SI 0 "nonimmediate_operand"
> -    "=r,m ,*y,*y,?*y,?m,?r,?*y,*v,*v,*v,m ,?r,?*v,*k,*k ,*rm,*k")
> +    "=r,m ,*y,*y,?*y,?m,?r,?*y,*v,*v,*v,m ,?r,?*v,*k,*k ,*k,*rm,*k")
>         (match_operand:SI 1 "general_operand"
> -    "g ,re,C ,*y,m  ,*y,*y,r  ,C ,*v,m ,*v,*v,r  ,*r,*km,*k ,CBC"))]
> +    "g ,re,C ,*y,Bk ,*y,*y,r  ,C ,*v,Bk,*v,*v,r  ,*r,*k, *Bk,*k ,CBC"))]
>    "!(MEM_P (operands[0]) && MEM_P (operands[1]))
>     && ix86_hardreg_mov_ok (operands[0], operands[1])"
>  {
> @@ -2452,9 +2452,9 @@ (define_insn "*movsi_internal"
>               (const_string "sselog1")
>             (eq_attr "alternative" "9,10,11,12,13")
>               (const_string "ssemov")
> -           (eq_attr "alternative" "14,15,16")
> +           (eq_attr "alternative" "14,15,16,17")
>               (const_string "mskmov")
> -           (eq_attr "alternative" "17")
> +           (eq_attr "alternative" "18")
>               (const_string "msklog")
>             (and (match_operand 0 "register_operand")
>                  (match_operand 1 "pic_32bit_operand"))
> diff --git a/gcc/testsuite/gcc.target/i386/pr103275.c b/gcc/testsuite/gcc.target/i386/pr103275.c
> new file mode 100644
> index 00000000000..288e680ffb2
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/i386/pr103275.c
> @@ -0,0 +1,148 @@
> +/* { dg-do compile { target ia32 } }  */
> +/* { dg-options "-O2 -march=tigerlake -fPIC" } */
> +/* { dg-final { scan-assembler-not {(?n)kmovd.*@gotntpoff} } }  */

Can you please minimize the testcase?

Uros.

> +
> +typedef unsigned short uint16_t;
> +typedef int int32_t;
> +typedef unsigned int uint32_t;
> +typedef unsigned char uint8_t;
> +
> +typedef uint32_t in_addr_t;
> +struct in_addr { in_addr_t s_addr; };
> +
> +extern __thread const uint16_t * __libc_tsd_CTYPE_B __attribute__ ((tls_model ("initial-exec")));
> +extern __thread int __libc_errno __attribute__ ((tls_model ("initial-exec")));
> +
> +enum
> +{
> +  _ISspace = ((5) < 8 ? ((1 << (5)) << 8) : ((1 << (5)) >> 8)),
> +};
> +
> +
> +extern inline const uint16_t ** __attribute__ ((const))
> +__ctype_b_loc (void)
> +{
> +  return (&__libc_tsd_CTYPE_B);
> +}
> +
> +extern unsigned long strtoul (const char*, char**, int);
> +extern uint32_t __bswap_32 (in_addr_t);
> +static int
> +inet_aton_end (const char *cp, struct in_addr *addr, const char **endp)
> +{
> +  static const in_addr_t max[4] = { 0xffffffff, 0xffffff, 0xffff, 0xff };
> +  in_addr_t val;
> +  char c;
> +  union iaddr
> +  {
> +    uint8_t bytes[4];
> +    uint32_t word;
> +  } res;
> +  uint8_t *pp = res.bytes;
> +  int digit;
> +
> +  int saved_errno = __libc_errno;
> +  (__libc_errno = (0));
> +
> +  res.word = 0;
> +
> +  c = *cp;
> +  for (;;)
> +    {
> +
> +
> +      if (!({ int __c = (c); __c >= '0' && __c <= '9'; }))
> + goto ret_0;
> +      {
> + char *endp;
> + unsigned long ul = strtoul (cp, &endp, 0);
> + if (ul ==
> +          (0x7fffffffL * 2UL + 1UL)
> +                    && __libc_errno ==
> +                                34
> +                                      )
> +   goto ret_0;
> + if (ul > 0xfffffffful)
> +   goto ret_0;
> + val = ul;
> + digit = cp != endp;
> + cp = endp;
> +      }
> +      c = *cp;
> +      if (c == '.')
> + {
> +
> +
> +
> +
> +   if (pp > res.bytes + 2 || val > 0xff)
> +     goto ret_0;
> +   *pp++ = val;
> +   c = *++cp;
> + }
> +      else
> + break;
> +    }
> +
> +  if (c != '\0' && (!(((c) & ~0x7f) == 0) || !((*__ctype_b_loc ())[(int) ((c))] & (unsigned short int) _ISspace)))
> +    goto ret_0;
> +
> +  if (!digit)
> +    goto ret_0;
> +
> +
> +
> +  if (val > max[pp - res.bytes])
> +    goto ret_0;
> +
> +  if (addr !=
> +             ((void *)0)
> +                 )
> +    addr->s_addr = res.word | __bswap_32 (val);
> +  *endp = cp;
> +
> +  (__libc_errno = (saved_errno));
> +  return 1;
> +
> + ret_0:
> +  (__libc_errno = (saved_errno));
> +  return 0;
> +}
> +
> +int
> +__inet_aton_exact (const char *cp, struct in_addr *addr)
> +{
> +  struct in_addr val;
> +  const char *endp;
> +
> +  if (inet_aton_end (cp, &val, &endp) != 0 && *endp == 0)
> +    {
> +      *addr = val;
> +      return 1;
> +    }
> +  else
> +    return 0;
> +}
> +
> +
> +
> +int
> +__inet_aton_ignore_trailing (const char *cp, struct in_addr *addr)
> +{
> +  const char *endp;
> +  return inet_aton_end (cp, addr, &endp);
> +}
> +extern __typeof (__inet_aton_ignore_trailing) inet_aton __attribute__ ((weak, alias ("__inet_aton_ignore_trailing"))) __attribute__ ((__copy__ (__inet_aton_ignore_trailing)));
> +
> +
> +
> +in_addr_t
> +__inet_addr (const char *cp)
> +{
> +  struct in_addr val;
> +  const char *endp;
> +  if (inet_aton_end (cp, &val, &endp))
> +    return val.s_addr;
> +  return ((in_addr_t) 0xffffffff);
> +}
> +extern __typeof (__inet_addr) inet_addr __attribute__ ((weak, alias ("__inet_addr"))) __attribute__ ((__copy__ (__inet_addr)));
> --
> 2.18.1
>
diff mbox series

Patch

diff --git a/gcc/config/i386/constraints.md b/gcc/config/i386/constraints.md
index 87cceac4cfb..489c76164a1 100644
--- a/gcc/config/i386/constraints.md
+++ b/gcc/config/i386/constraints.md
@@ -186,6 +186,11 @@  (define_special_memory_constraint "Bc"
   (and (match_operand 0 "memory_operand")
        (match_test "constant_address_p (XEXP (op, 0))")))
 
+(define_special_memory_constraint "Bk"
+  "@internal notls memory operand."
+  (and (match_operand 0 "memory_operand")
+       (match_test "ix86_notls_memory (op)")))
+
 (define_special_memory_constraint "Bn"
   "@internal Memory operand without REX prefix."
   (match_operand 0 "norex_memory_operand"))
diff --git a/gcc/config/i386/i386-protos.h b/gcc/config/i386/i386-protos.h
index 7e05510c679..1fb09be8b7e 100644
--- a/gcc/config/i386/i386-protos.h
+++ b/gcc/config/i386/i386-protos.h
@@ -243,6 +243,7 @@  extern unsigned int ix86_get_callcvt (const_tree);
 #endif
 
 extern rtx ix86_tls_module_base (void);
+extern bool ix86_notls_memory (rtx);
 extern bool ix86_tls_address_pattern_p (rtx);
 extern rtx ix86_rewrite_tls_address (rtx);
 
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index c246c8736f5..f1b7f57b0ca 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -11628,6 +11628,40 @@  legitimize_tls_address (rtx x, enum tls_model model, bool for_mov)
   return dest;
 }
 
+/* Return true if it's not tls memory,
+   NB: it's different from ix86_tls_address_pattern_p since it also matchs
+   gottpoff/gotntpoff.
+   It's used to prevent KMOV/VMOV in TLS code sequences which require integer
+   MOV instructions, refer to PR103275.  */
+bool
+ix86_notls_memory (rtx mem)
+{
+  gcc_assert (MEM_P (mem));
+
+  rtx addr = XEXP (mem, 0);
+  subrtx_var_iterator::array_type array;
+  FOR_EACH_SUBRTX_VAR (iter, array, addr, ALL)
+    {
+      rtx op = *iter;
+      if (GET_CODE (op) == UNSPEC)
+	switch (XINT (op, 1))
+	  {
+	  case UNSPEC_GOTNTPOFF:
+	    return false;
+	  case UNSPEC_TPOFF:
+	    if (!TARGET_64BIT)
+	      return false;
+	    break;
+	  default:
+	    break;
+	  }
+      /* Should iter.skip_subrtxes ();
+	 if there's no inner UNSPEC in addr???.  */
+    }
+
+  return true;
+}
+
 /* Return true if OP refers to a TLS address.  */
 bool
 ix86_tls_address_pattern_p (rtx op)
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index 7b2de60706d..9feba81974b 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -2164,9 +2164,9 @@  (define_split
 
 (define_insn "*movdi_internal"
   [(set (match_operand:DI 0 "nonimmediate_operand"
-    "=r  ,o  ,r,r  ,r,m ,*y,*y,?*y,?m,?r,?*y,*v,*v,*v,m ,m,?r ,?*Yd,?r,?*v,?*y,?*x,*k,*k ,*r,*m,*k")
+    "=r  ,o  ,r,r  ,r,m ,*y,*y,?*y,?m,?r,?*y,*v,*v,*v,m ,m,?r ,?*Yd,?r,?*v,?*y,?*x,*k,*k,*k ,*r,*m,*k")
 	(match_operand:DI 1 "general_operand"
-    "riFo,riF,Z,rem,i,re,C ,*y,m  ,*y,*y,r  ,C ,*v,m ,*v,v,*Yd,r   ,*v,r  ,*x ,*y ,*r,*km,*k,*k,CBC"))]
+    "riFo,riF,Z,rem,i,re,C ,*y,Bk ,*y,*y,r  ,C ,*v,Bk,*v,v,*Yd,r   ,*v,r  ,*x ,*y ,*r,*k,*Bk,*k,*k,CBC"))]
   "!(MEM_P (operands[0]) && MEM_P (operands[1]))
    && ix86_hardreg_mov_ok (operands[0], operands[1])"
 {
@@ -2228,7 +2228,7 @@  (define_insn "*movdi_internal"
   [(set (attr "isa")
      (cond [(eq_attr "alternative" "0,1,17,18")
 	      (const_string "nox64")
-	    (eq_attr "alternative" "2,3,4,5,10,11,23,25")
+	    (eq_attr "alternative" "2,3,4,5,10,11,23,26")
 	      (const_string "x64")
 	    (eq_attr "alternative" "19,20")
 	      (const_string "x64_sse2")
@@ -2249,9 +2249,9 @@  (define_insn "*movdi_internal"
 	      (const_string "ssemov")
 	    (eq_attr "alternative" "21,22")
 	      (const_string "ssecvt")
-	    (eq_attr "alternative" "23,24,25,26")
+	    (eq_attr "alternative" "23,24,25,26,27")
 	      (const_string "mskmov")
-	    (eq_attr "alternative" "27")
+	    (eq_attr "alternative" "28")
 	      (const_string "msklog")
 	    (and (match_operand 0 "register_operand")
 		 (match_operand 1 "pic_32bit_operand"))
@@ -2385,9 +2385,9 @@  (define_peephole2
 
 (define_insn "*movsi_internal"
   [(set (match_operand:SI 0 "nonimmediate_operand"
-    "=r,m ,*y,*y,?*y,?m,?r,?*y,*v,*v,*v,m ,?r,?*v,*k,*k ,*rm,*k")
+    "=r,m ,*y,*y,?*y,?m,?r,?*y,*v,*v,*v,m ,?r,?*v,*k,*k ,*k,*rm,*k")
 	(match_operand:SI 1 "general_operand"
-    "g ,re,C ,*y,m  ,*y,*y,r  ,C ,*v,m ,*v,*v,r  ,*r,*km,*k ,CBC"))]
+    "g ,re,C ,*y,Bk ,*y,*y,r  ,C ,*v,Bk,*v,*v,r  ,*r,*k, *Bk,*k ,CBC"))]
   "!(MEM_P (operands[0]) && MEM_P (operands[1]))
    && ix86_hardreg_mov_ok (operands[0], operands[1])"
 {
@@ -2452,9 +2452,9 @@  (define_insn "*movsi_internal"
 	      (const_string "sselog1")
 	    (eq_attr "alternative" "9,10,11,12,13")
 	      (const_string "ssemov")
-	    (eq_attr "alternative" "14,15,16")
+	    (eq_attr "alternative" "14,15,16,17")
 	      (const_string "mskmov")
-	    (eq_attr "alternative" "17")
+	    (eq_attr "alternative" "18")
 	      (const_string "msklog")
 	    (and (match_operand 0 "register_operand")
 		 (match_operand 1 "pic_32bit_operand"))
diff --git a/gcc/testsuite/gcc.target/i386/pr103275.c b/gcc/testsuite/gcc.target/i386/pr103275.c
new file mode 100644
index 00000000000..288e680ffb2
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr103275.c
@@ -0,0 +1,148 @@ 
+/* { dg-do compile { target ia32 } }  */
+/* { dg-options "-O2 -march=tigerlake -fPIC" } */
+/* { dg-final { scan-assembler-not {(?n)kmovd.*@gotntpoff} } }  */
+
+typedef unsigned short uint16_t;
+typedef int int32_t;
+typedef unsigned int uint32_t;
+typedef unsigned char uint8_t;
+
+typedef uint32_t in_addr_t;
+struct in_addr { in_addr_t s_addr; };
+
+extern __thread const uint16_t * __libc_tsd_CTYPE_B __attribute__ ((tls_model ("initial-exec")));
+extern __thread int __libc_errno __attribute__ ((tls_model ("initial-exec")));
+
+enum
+{
+  _ISspace = ((5) < 8 ? ((1 << (5)) << 8) : ((1 << (5)) >> 8)),
+};
+
+
+extern inline const uint16_t ** __attribute__ ((const))
+__ctype_b_loc (void)
+{
+  return (&__libc_tsd_CTYPE_B);
+}
+
+extern unsigned long strtoul (const char*, char**, int);
+extern uint32_t __bswap_32 (in_addr_t);
+static int
+inet_aton_end (const char *cp, struct in_addr *addr, const char **endp)
+{
+  static const in_addr_t max[4] = { 0xffffffff, 0xffffff, 0xffff, 0xff };
+  in_addr_t val;
+  char c;
+  union iaddr
+  {
+    uint8_t bytes[4];
+    uint32_t word;
+  } res;
+  uint8_t *pp = res.bytes;
+  int digit;
+
+  int saved_errno = __libc_errno;
+  (__libc_errno = (0));
+
+  res.word = 0;
+
+  c = *cp;
+  for (;;)
+    {
+
+
+      if (!({ int __c = (c); __c >= '0' && __c <= '9'; }))
+ goto ret_0;
+      {
+ char *endp;
+ unsigned long ul = strtoul (cp, &endp, 0);
+ if (ul == 
+          (0x7fffffffL * 2UL + 1UL) 
+                    && __libc_errno == 
+                                34
+                                      )
+   goto ret_0;
+ if (ul > 0xfffffffful)
+   goto ret_0;
+ val = ul;
+ digit = cp != endp;
+ cp = endp;
+      }
+      c = *cp;
+      if (c == '.')
+ {
+
+
+
+
+   if (pp > res.bytes + 2 || val > 0xff)
+     goto ret_0;
+   *pp++ = val;
+   c = *++cp;
+ }
+      else
+ break;
+    }
+
+  if (c != '\0' && (!(((c) & ~0x7f) == 0) || !((*__ctype_b_loc ())[(int) ((c))] & (unsigned short int) _ISspace)))
+    goto ret_0;
+
+  if (!digit)
+    goto ret_0;
+
+
+
+  if (val > max[pp - res.bytes])
+    goto ret_0;
+
+  if (addr != 
+             ((void *)0)
+                 )
+    addr->s_addr = res.word | __bswap_32 (val);
+  *endp = cp;
+
+  (__libc_errno = (saved_errno));
+  return 1;
+
+ ret_0:
+  (__libc_errno = (saved_errno));
+  return 0;
+}
+
+int
+__inet_aton_exact (const char *cp, struct in_addr *addr)
+{
+  struct in_addr val;
+  const char *endp;
+
+  if (inet_aton_end (cp, &val, &endp) != 0 && *endp == 0)
+    {
+      *addr = val;
+      return 1;
+    }
+  else
+    return 0;
+}
+
+
+
+int
+__inet_aton_ignore_trailing (const char *cp, struct in_addr *addr)
+{
+  const char *endp;
+  return inet_aton_end (cp, addr, &endp);
+}
+extern __typeof (__inet_aton_ignore_trailing) inet_aton __attribute__ ((weak, alias ("__inet_aton_ignore_trailing"))) __attribute__ ((__copy__ (__inet_aton_ignore_trailing)));
+
+
+
+in_addr_t
+__inet_addr (const char *cp)
+{
+  struct in_addr val;
+  const char *endp;
+  if (inet_aton_end (cp, &val, &endp))
+    return val.s_addr;
+  return ((in_addr_t) 0xffffffff);
+}
+extern __typeof (__inet_addr) inet_addr __attribute__ ((weak, alias ("__inet_addr"))) __attribute__ ((__copy__ (__inet_addr)));