Commit ecbb5ea1041d2894f5efb9317acd519c4fd81ad5
1 parent
68238a9e
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
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3 changed files
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40 additions
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8 deletions
target-alpha/op_helper.c
| ... | ... | @@ -158,22 +158,22 @@ uint64_t helper_addlv (uint64_t op1, uint64_t op2) |
| 158 | 158 | |
| 159 | 159 | uint64_t helper_subqv (uint64_t op1, uint64_t op2) |
| 160 | 160 | { |
| 161 | - uint64_t tmp = op1; | |
| 162 | - op1 -= op2; | |
| 163 | - if (unlikely(((~tmp) ^ op1 ^ (-1ULL)) & ((~tmp) ^ op2) & (1ULL << 63))) { | |
| 161 | + uint64_t res; | |
| 162 | + res = op1 - op2; | |
| 163 | + if (unlikely((op1 ^ op2) & (res ^ op1) & (1ULL << 63))) { | |
| 164 | 164 | helper_excp(EXCP_ARITH, EXCP_ARITH_OVERFLOW); |
| 165 | 165 | } |
| 166 | - return op1; | |
| 166 | + return res; | |
| 167 | 167 | } |
| 168 | 168 | |
| 169 | 169 | uint64_t helper_sublv (uint64_t op1, uint64_t op2) |
| 170 | 170 | { |
| 171 | - uint64_t tmp = op1; | |
| 172 | - op1 = (uint32_t)(op1 - op2); | |
| 173 | - if (unlikely(((~tmp) ^ op1 ^ (-1UL)) & ((~tmp) ^ op2) & (1UL << 31))) { | |
| 171 | + uint32_t res; | |
| 172 | + res = op1 - op2; | |
| 173 | + if (unlikely((op1 ^ op2) & (res ^ op1) & (1UL << 31))) { | |
| 174 | 174 | helper_excp(EXCP_ARITH, EXCP_ARITH_OVERFLOW); |
| 175 | 175 | } |
| 176 | - return op1; | |
| 176 | + return res; | |
| 177 | 177 | } |
| 178 | 178 | |
| 179 | 179 | uint64_t helper_mullv (uint64_t op1, uint64_t op2) | ... | ... |
tests/alpha/Makefile
tests/alpha/test-ovf.c
0 → 100644
| 1 | +static long test_subqv (long a, long b) | |
| 2 | +{ | |
| 3 | + long res; | |
| 4 | + | |
| 5 | + asm ("subq/v %1,%2,%0" | |
| 6 | + : "=r" (res) : "r" (a), "r" (b)); | |
| 7 | + return res; | |
| 8 | +} | |
| 9 | +static struct { | |
| 10 | + long (*func)(long, long); | |
| 11 | + long a; | |
| 12 | + long b; | |
| 13 | + long r; | |
| 14 | +} vectors[] = | |
| 15 | + { | |
| 16 | + {test_subqv, 0, 0x7d54000, 0xfffffffff82ac000L} | |
| 17 | + }; | |
| 18 | + | |
| 19 | +int main (void) | |
| 20 | +{ | |
| 21 | + int i; | |
| 22 | + | |
| 23 | + for (i = 0; i < sizeof (vectors)/sizeof(vectors[0]); i++) | |
| 24 | + if ((*vectors[i].func)(vectors[i].a, vectors[i].b) != vectors[i].r) { | |
| 25 | + write(1, "Failed\n", 7); | |
| 26 | + } | |
| 27 | + write(1, "OK\n", 3); | |
| 28 | + return 0; | |
| 29 | +} | ... | ... |