builtins.c (expand_builtin_strcat): Optimize constant strings.

* builtins.c (expand_builtin_strcat): Optimize constant strings.

testsuite:
	* gcc.c-torture/execute/string-opt-9.c: Add more strcat cases.

From-SVN: r70317
This commit is contained in:
Kaveh R. Ghazi 2003-08-11 03:15:15 +00:00 committed by Kaveh Ghazi
parent d9148cf498
commit 0235f85590
4 changed files with 87 additions and 9 deletions

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@ -1,3 +1,7 @@
2003-08-10 Kaveh R. Ghazi <ghazi@caip.rutgers.edu>
* builtins.c (expand_builtin_strcat): Optimize constant strings.
2003-08-10 Gabriel Dos Reis <gdr@integrable-solutions.net>
* pretty-print.c (pp_base_indent): Rename from pp_indent.

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@ -3577,9 +3577,52 @@ expand_builtin_strcat (tree arglist, rtx target, enum machine_mode mode)
src = TREE_VALUE (TREE_CHAIN (arglist));
const char *p = c_getstr (src);
/* If the string length is zero, return the dst parameter. */
if (p && *p == '\0')
return expand_expr (dst, target, mode, EXPAND_NORMAL);
if (p)
{
/* If the string length is zero, return the dst parameter. */
if (*p == '\0')
return expand_expr (dst, target, mode, EXPAND_NORMAL);
else if (!optimize_size)
{
/* Otherwise if !optimize_size, see if we can store by
pieces into (dst + strlen(dst)). */
tree newdst, arglist,
strlen_fn = implicit_built_in_decls[BUILT_IN_STRLEN];
/* This is the length argument. */
arglist = build_tree_list (NULL_TREE,
fold (size_binop (PLUS_EXPR,
c_strlen (src, 0),
ssize_int (1))));
/* Prepend src argument. */
arglist = tree_cons (NULL_TREE, src, arglist);
/* We're going to use dst more than once. */
dst = save_expr (dst);
/* Create strlen (dst). */
newdst =
fold (build_function_call_expr (strlen_fn,
build_tree_list (NULL_TREE,
dst)));
/* Create (dst + strlen (dst)). */
newdst = fold (build (PLUS_EXPR, TREE_TYPE (dst), dst, newdst));
/* Prepend the new dst argument. */
arglist = tree_cons (NULL_TREE, newdst, arglist);
/* We don't want to get turned into a memcpy if the
target is const0_rtx, i.e. when the return value
isn't used. That would produce pessimized code so
pass in a target of zero, it should never actually be
used. If this was successful return the original
dst, not the result of mempcpy. */
if (expand_builtin_mempcpy (arglist, /*target=*/0, mode, /*endp=*/0))
return expand_expr (dst, target, mode, EXPAND_NORMAL);
else
return 0;
}
}
return 0;
}

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@ -1,3 +1,7 @@
2003-08-10 Kaveh R. Ghazi <ghazi@caip.rutgers.edu>
* gcc.c-torture/execute/string-opt-9.c: Add more strcat cases.
2003-08-10 Mark Mitchell <mark@codesourcery.com>
PR c++/11789.C

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@ -10,6 +10,10 @@ typedef __SIZE_TYPE__ size_t;
extern char *strcat (char *, const char *);
extern char *strcpy (char *, const char *);
extern int strcmp (const char *, const char *);
extern void *memset (void *, int, size_t);
extern int memcmp (const void *, const void *, size_t);
#define RESET_DST_WITH(FILLER) \
do { memset (dst, 'X', sizeof (dst)); strcpy (dst, (FILLER)); } while (0)
int main ()
{
@ -17,25 +21,48 @@ int main ()
const char *const s2 = "";
char dst[64], *d2;
strcpy (dst, s1);
RESET_DST_WITH (s1);
if (strcat (dst, "") != dst || strcmp (dst, s1))
abort();
strcpy (dst, s1);
RESET_DST_WITH (s1);
if (strcat (dst, s2) != dst || strcmp (dst, s1))
abort();
strcpy (dst, s1); d2 = dst;
RESET_DST_WITH (s1); d2 = dst;
if (strcat (++d2, s2) != dst+1 || d2 != dst+1 || strcmp (dst, s1))
abort();
strcpy (dst, s1); d2 = dst;
RESET_DST_WITH (s1); d2 = dst;
if (strcat (++d2+5, s2) != dst+6 || d2 != dst+1 || strcmp (dst, s1))
abort();
strcpy (dst, s1); d2 = dst;
RESET_DST_WITH (s1); d2 = dst;
if (strcat (++d2+5, s1+11) != dst+6 || d2 != dst+1 || strcmp (dst, s1))
abort();
#ifndef __OPTIMIZE_SIZE__
RESET_DST_WITH (s1);
if (strcat (dst, " 1111") != dst
|| memcmp (dst, "hello world 1111\0XXX", 20))
abort();
RESET_DST_WITH (s1);
if (strcat (dst+5, " 2222") != dst+5
|| memcmp (dst, "hello world 2222\0XXX", 20))
abort();
RESET_DST_WITH (s1); d2 = dst;
if (strcat (++d2+5, " 3333") != dst+6 || d2 != dst+1
|| memcmp (dst, "hello world 3333\0XXX", 20))
abort();
RESET_DST_WITH (s1);
strcat (strcat (strcat (strcat (strcat (strcat (dst, ": this "), ""),
"is "), "a "), "test"), ".");
if (memcmp (dst, "hello world: this is a test.\0X", 30))
abort();
#endif
/* Test at least one instance of the __builtin_ style. We do this
to ensure that it works and that the prototype is correct. */
strcpy (dst, s1);
RESET_DST_WITH (s1);
if (__builtin_strcat (dst, "") != dst || strcmp (dst, s1))
abort();