diff options
| author | aurel32 <aurel32@c046a42c-6fe2-441c-8c8c-71466251a162> | 2009-04-10 21:27:15 +0000 |
|---|---|---|
| committer | aurel32 <aurel32@c046a42c-6fe2-441c-8c8c-71466251a162> | 2009-04-10 21:27:15 +0000 |
| commit | ecbb5ea1041d2894f5efb9317acd519c4fd81ad5 (patch) | |
| tree | 72cd66d31fdd2c87d191f3be9c84f4f72a2b20a7 /target-alpha | |
| parent | 68238a9e90708740200e652631ee1356dd55147d (diff) | |
target-alpha: overflow condition for sublv and subqv
The conditions to detect overflow in sub operations was wrong.
This patch is necessary to boot Tru64.
Signed-off-by: Tristan Gingold <gingold@adacore.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7073 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'target-alpha')
| -rw-r--r-- | target-alpha/op_helper.c | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/target-alpha/op_helper.c b/target-alpha/op_helper.c index 7ad1b3d55c..e61fa7396c 100644 --- a/target-alpha/op_helper.c +++ b/target-alpha/op_helper.c @@ -158,22 +158,22 @@ uint64_t helper_addlv (uint64_t op1, uint64_t op2) uint64_t helper_subqv (uint64_t op1, uint64_t op2) { - uint64_t tmp = op1; - op1 -= op2; - if (unlikely(((~tmp) ^ op1 ^ (-1ULL)) & ((~tmp) ^ op2) & (1ULL << 63))) { + uint64_t res; + res = op1 - op2; + if (unlikely((op1 ^ op2) & (res ^ op1) & (1ULL << 63))) { helper_excp(EXCP_ARITH, EXCP_ARITH_OVERFLOW); } - return op1; + return res; } uint64_t helper_sublv (uint64_t op1, uint64_t op2) { - uint64_t tmp = op1; - op1 = (uint32_t)(op1 - op2); - if (unlikely(((~tmp) ^ op1 ^ (-1UL)) & ((~tmp) ^ op2) & (1UL << 31))) { + uint32_t res; + res = op1 - op2; + if (unlikely((op1 ^ op2) & (res ^ op1) & (1UL << 31))) { helper_excp(EXCP_ARITH, EXCP_ARITH_OVERFLOW); } - return op1; + return res; } uint64_t helper_mullv (uint64_t op1, uint64_t op2) |