diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/core/arm/interpreter/armemu.cpp | 32 |
1 files changed, 30 insertions, 2 deletions
diff --git a/src/core/arm/interpreter/armemu.cpp b/src/core/arm/interpreter/armemu.cpp index 449fd3640..d54dbeac5 100644 --- a/src/core/arm/interpreter/armemu.cpp +++ b/src/core/arm/interpreter/armemu.cpp @@ -6531,8 +6531,36 @@ L_stm_s_takeabort: return 1; } break; - case 0x75: - printf ("Unhandled v6 insn: smmla/smmls/smmul\n"); + case 0x75: // SMMLA, SMMUL, and SMMLS + { + const u8 rm_idx = BITS(8, 11); + const u8 rn_idx = BITS(0, 3); + const u8 ra_idx = BITS(12, 15); + const u8 rd_idx = BITS(16, 19); + const bool do_round = (BIT(5) == 1); + + const u32 rm_val = state->Reg[rm_idx]; + const u32 rn_val = state->Reg[rn_idx]; + + // Assume SMMUL by default. + s64 result = (s64)(s32)rn_val * (s64)(s32)rm_val; + + if (ra_idx != 15) { + const u32 ra_val = state->Reg[ra_idx]; + + // SMMLA, otherwise SMMLS + if (BIT(6) == 0) + result += ((s64)ra_val << 32); + else + result = ((s64)ra_val << 32) - result; + } + + if (do_round) + result += 0x80000000; + + state->Reg[rd_idx] = ((result >> 32) & 0xFFFFFFFF); + return 1; + } break; case 0x78: if (BITS(20, 24) == 0x18) |