diff options
Diffstat (limited to 'src/core/arm/interpreter')
| -rw-r--r-- | src/core/arm/interpreter/armsupp.cpp | 16 | 
1 files changed, 16 insertions, 0 deletions
| diff --git a/src/core/arm/interpreter/armsupp.cpp b/src/core/arm/interpreter/armsupp.cpp index 68ac2a0ce..e2626eefb 100644 --- a/src/core/arm/interpreter/armsupp.cpp +++ b/src/core/arm/interpreter/armsupp.cpp @@ -418,6 +418,22 @@ ARMul_NegZero (ARMul_State * state, ARMword result)      }  } +// Add with carry, indicates if a carry-out or signed overflow occurred. +u32 AddWithCarry(u32 left, u32 right, u32 carry_in, bool* carry_out_occurred, bool* overflow_occurred) +{ +    u64 unsigned_sum = (u64)left + (u64)right + (u64)carry_in; +    s64 signed_sum = (s64)(s32)left + (s64)(s32)right + (s64)carry_in; +    u64 result = (unsigned_sum & 0xFFFFFFFF); + +    if (carry_out_occurred) +        *carry_out_occurred = (result != unsigned_sum); + +    if (overflow_occurred) +        *overflow_occurred = ((s64)(s32)result != signed_sum); + +    return (u32)result; +} +  // Compute whether an addition of A and B, giving RESULT, overflowed.  bool AddOverflow(ARMword a, ARMword b, ARMword result)  { | 
