tcg-arm: Use AT_PLATFORM to detect the host ISA

With this we can generate armv7 insns even when the OS compiles for a
lower common denominator.  The macros are arranged so that when we do
compile for a given ISA, all of the runtime checks for that ISA are
optimized away.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Richard Henderson 2013-06-06 10:46:35 -07:00
parent cb91021a47
commit 1e709f3833

View File

@ -41,6 +41,8 @@
# endif
#endif
static int arm_arch = __ARM_ARCH;
#if defined(__ARM_ARCH_5T__) \
|| defined(__ARM_ARCH_5TE__) || defined(__ARM_ARCH_5TEJ__)
# define use_armv5t_instructions 1
@ -48,8 +50,8 @@
# define use_armv5t_instructions use_armv6_instructions
#endif
#define use_armv6_instructions (__ARM_ARCH >= 6)
#define use_armv7_instructions (__ARM_ARCH >= 7)
#define use_armv6_instructions (__ARM_ARCH >= 6 || arm_arch >= 6)
#define use_armv7_instructions (__ARM_ARCH >= 7 || arm_arch >= 7)
#ifndef use_idiv_instructions
bool use_idiv_instructions;
@ -2028,12 +2030,22 @@ static const TCGTargetOpDef arm_op_defs[] = {
static void tcg_target_init(TCGContext *s)
{
#if defined(CONFIG_GETAUXVAL) && !defined(use_idiv_instructions)
#if defined(CONFIG_GETAUXVAL)
/* Only probe for the platform and capabilities if we havn't already
determined maximum values at compile time. */
# if !defined(use_idiv_instructions)
{
unsigned long hwcap = getauxval(AT_HWCAP);
use_idiv_instructions = (hwcap & HWCAP_ARM_IDIVA) != 0;
}
#endif
# endif
if (__ARM_ARCH < 7) {
const char *pl = (const char *)getauxval(AT_PLATFORM);
if (pl != NULL && pl[0] == 'v' && pl[1] >= '4' && pl[1] <= '9') {
arm_arch = pl[1] - '0';
}
}
#endif /* GETAUXVAL */
tcg_regset_set32(tcg_target_available_regs[TCG_TYPE_I32], 0, 0xffff);
tcg_regset_set32(tcg_target_call_clobber_regs, 0,