+2007-07-10 David Daney <ddaney@avtrex.com>
+
+ * builtins.def (BUILT_IN_CLEAR_CACHE): New builtin.
+ * builtins.c (expand_builtin___clear_cache): New function.
+ (expand_builtin): Call expand_builtin___clear_cache for
+ BUILT_IN_CLEAR_CACHE case.
+ * doc/extend.texi (__builtin___clear_cache): Document new builtin.
+ * doc/md.texi (clear_cache): Document new instruction pattern.
+ * testsuite/gcc.dg/builtins-64.c: New test.
+
2007-07-11 Hans-Peter Nilsson <hp@axis.com>
* config/cris/cris.md ("movsi"): Fix typo in last change.
return const0_rtx;
}
+/* Expand a call to __builtin___clear_cache. */
+
+static rtx
+expand_builtin___clear_cache (tree exp ATTRIBUTE_UNUSED)
+{
+#ifndef HAVE_clear_cache
+#ifdef CLEAR_INSN_CACHE
+ /* There is no "clear_cache" insn, and __clear_cache() in libgcc
+ does something. Just do the default expansion to a call to
+ __clear_cache(). */
+ return NULL_RTX;
+#else
+ /* There is no "clear_cache" insn, and __clear_cache() in libgcc
+ does nothing. There is no need to call it. Do nothing. */
+ return const0_rtx;
+#endif /* CLEAR_INSN_CACHE */
+#else
+ /* We have a "clear_cache" insn, and it will handle everything. */
+ tree begin, end;
+ rtx begin_rtx, end_rtx;
+ enum insn_code icode;
+
+ /* We must not expand to a library call. If we did, any
+ fallback library function in libgcc that might contain a call to
+ __builtin___clear_cache() would recurse infinitely. */
+ if (!validate_arglist (exp, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
+ {
+ error ("both arguments to %<__builtin___clear_cache%> must be pointers");
+ return const0_rtx;
+ }
+
+ if (HAVE_clear_cache)
+ {
+ icode = CODE_FOR_clear_cache;
+
+ begin = CALL_EXPR_ARG (exp, 0);
+ begin_rtx = expand_expr (begin, NULL_RTX, Pmode, EXPAND_NORMAL);
+ begin_rtx = convert_memory_address (Pmode, begin_rtx);
+ if (!insn_data[icode].operand[0].predicate (begin_rtx, Pmode))
+ begin_rtx = copy_to_mode_reg (Pmode, begin_rtx);
+
+ end = CALL_EXPR_ARG (exp, 1);
+ end_rtx = expand_expr (end, NULL_RTX, Pmode, EXPAND_NORMAL);
+ end_rtx = convert_memory_address (Pmode, end_rtx);
+ if (!insn_data[icode].operand[1].predicate (end_rtx, Pmode))
+ end_rtx = copy_to_mode_reg (Pmode, end_rtx);
+
+ emit_insn (gen_clear_cache (begin_rtx, end_rtx));
+ }
+ return const0_rtx;
+#endif /* HAVE_clear_cache */
+}
+
/* Given a trampoline address, make sure it satisfies TRAMPOLINE_ALIGNMENT. */
static rtx
return const0_rtx;
return expand_builtin_next_arg ();
+ case BUILT_IN_CLEAR_CACHE:
+ target = expand_builtin___clear_cache (exp);
+ if (target)
+ return target;
+ break;
+
case BUILT_IN_CLASSIFY_TYPE:
return expand_builtin_classify_type (exp);
/* This file contains the definitions and documentation for the
builtins used in the GNU compiler.
- Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006
+ Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
Free Software Foundation, Inc.
This file is part of GCC.
DEF_GCC_BUILTIN (BUILT_IN_ARGS_INFO, "args_info", BT_FN_INT_INT, ATTR_NULL)
DEF_GCC_BUILTIN (BUILT_IN_BSWAP32, "bswap32", BT_FN_UINT32_UINT32, ATTR_CONST_NOTHROW_LIST)
DEF_GCC_BUILTIN (BUILT_IN_BSWAP64, "bswap64", BT_FN_UINT64_UINT64, ATTR_CONST_NOTHROW_LIST)
+DEF_EXT_LIB_BUILTIN (BUILT_IN_CLEAR_CACHE, "__clear_cache", BT_FN_VOID_PTR_PTR, ATTR_NOTHROW_LIST)
DEF_LIB_BUILTIN (BUILT_IN_CALLOC, "calloc", BT_FN_PTR_SIZE_SIZE, ATTR_MALLOC_NOTHROW_LIST)
DEF_GCC_BUILTIN (BUILT_IN_CLASSIFY_TYPE, "classify_type", BT_FN_INT_VAR, ATTR_NULL)
DEF_GCC_BUILTIN (BUILT_IN_CLZ, "clz", BT_FN_INT_UINT, ATTR_CONST_NOTHROW_LIST)
when testing pointer or floating-point values.
@end deftypefn
+@deftypefn {Built-in Function} void __builtin___clear_cache (char *@var{begin}, char *@var{end})
+This function is used to flush the processor's instruction cache for
+the region of memory between @var{begin} inclusive and @var{end}
+exclusive. Some targets require that the instruction cache be
+flushed, after modifying memory containing code, in order to obtain
+deterministic behavior.
+
+If the target does not require instruction cache flushes,
+@code{__builtin___clear_cache} has no effect. Otherwise either
+instructions are emitted in-line to clear the instruction cache or a
+call to the @code{__clear_cache} function in libgcc is made.
+@end deftypefn
+
@deftypefn {Built-in Function} void __builtin_prefetch (const void *@var{addr}, ...)
This function is used to minimize cache-miss latency by moving data into
a cache before it is accessed.
If this pattern is not defined, then a plain compare pattern and
conditional branch pattern is used.
+@cindex @code{clear_cache} instruction pattern
+@item @samp{clear_cache}
+
+This pattern, if defined, flushes the instruction cache for a region of
+memory. The region is bounded to by the Pmode pointers in operand 0
+inclusive and operand 1 exclusive.
+
+If this pattern is not defined, a call to the library function
+@code{__clear_cache} is used.
+
@end table
@end ifset
--- /dev/null
+/* { dg-do run } */
+
+int main ()
+{
+ char *mem = __builtin_alloca (40);
+ __builtin___clear_cache (mem, mem + 40);
+ return 0;
+}