diff options
Diffstat (limited to 'results/classifier/user-mode-bugs/2319')
| -rw-r--r-- | results/classifier/user-mode-bugs/2319 | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/results/classifier/user-mode-bugs/2319 b/results/classifier/user-mode-bugs/2319 new file mode 100644 index 000000000..274bce817 --- /dev/null +++ b/results/classifier/user-mode-bugs/2319 @@ -0,0 +1,19 @@ + + +SPARC32-bit SDIV of negative divisor gives wrong result +Description of problem: +SDIV of negative divisor gives wrong result because of typo in helper_sdiv(). This is true for QEMU 9.0.0 and earlier. + +Place -1 in the Y register and -128 in another reg, then -120 in another register and do SDIV into a result register, instead of the proper value of 1 for the result, the incorrect value of 0 is produced. + +There is a typo in target/sparc/helper.c that causes the divisor to be consider unsigned, this patch fixes it: + +\*\*\* helper.c.ori Tue Apr 23 16:23:45 2024 --- helper.c Mon Apr 29 20:14:07 2024 + +--- + +\*\*\* 121,127 \*\*\*\* return (uint32_t)(b32 \< 0 ? INT32_MAX : INT32_MIN) | (-1ull \<\< 32); } + +! a64 /= b; r = a64; if (unlikely(r != a64)) { return (uint32_t)(a64 \< 0 ? INT32_MIN : INT32_MAX) | (-1ull \<\< 32); --- 121,127 ---- return (uint32_t)(b32 \< 0 ? INT32_MAX : INT32_MIN) | (-1ull \<\< 32); } + +! a64 /= b32; r = a64; if (unlikely(r != a64)) { return (uint32_t)(a64 \< 0 ? INT32_MIN : INT32_MAX) | (-1ull \<\< 32); |