diff options
| author | Mike Pavone <pavone@retrodev.com> | 2013-04-21 16:44:46 -0700 |
|---|---|---|
| committer | Mike Pavone <pavone@retrodev.com> | 2013-04-21 16:44:46 -0700 |
| commit | 823288d1d0fd99e54b1cde0c975916a5f1030025 (patch) | |
| tree | 86127a5f4387befa79219d1e1823de2ffcfc548c | |
| parent | 86772de0d569b77d2e62daafd3871a625fe6b5d7 (diff) | |
Fix overflow detection in divs. Fix negative immediate source for divs
| -rw-r--r-- | m68k_to_x86.c | 33 |
1 files changed, 24 insertions, 9 deletions
diff --git a/m68k_to_x86.c b/m68k_to_x86.c index ba7f14a..485c4e7 100644 --- a/m68k_to_x86.c +++ b/m68k_to_x86.c @@ -3126,8 +3126,10 @@ uint8_t * translate_m68k(uint8_t * dst, m68kinst * inst, x86_68k_options * opts) } case M68K_DIVS: case M68K_DIVU: - //TODO: Trap on division by zero + { + //TODO: cycle exact division dst = cycles(dst, inst->op == M68K_DIVS ? 158 : 140); + dst = mov_ir(dst, 0, FLAG_C, SZ_B); dst = push_r(dst, RDX); dst = push_r(dst, RAX); if (dst_op.mode == MODE_REG_DIRECT) { @@ -3136,7 +3138,7 @@ uint8_t * translate_m68k(uint8_t * dst, m68kinst * inst, x86_68k_options * opts) dst = mov_rdisp8r(dst, dst_op.base, dst_op.disp, RAX, SZ_D); } if (src_op.mode == MODE_IMMED) { - dst = mov_ir(dst, src_op.disp, SCRATCH2, SZ_D); + dst = mov_ir(dst, (src_op.disp & 0x8000) && inst->op == M68K_DIVS ? src_op.disp | 0xFFFF0000 : src_op.disp, SCRATCH2, SZ_D); } else if (src_op.mode == MODE_REG_DIRECT) { if (inst->op == M68K_DIVS) { dst = movsx_rr(dst, src_op.base, SCRATCH2, SZ_W, SZ_D); @@ -3150,6 +3152,15 @@ uint8_t * translate_m68k(uint8_t * dst, m68kinst * inst, x86_68k_options * opts) dst = movzx_rdisp8r(dst, src_op.base, src_op.disp, SCRATCH2, SZ_W, SZ_D); } } + dst = cmp_ir(dst, 0, SCRATCH2, SZ_D); + uint8_t * not_zero = dst+1; + dst = jcc(dst, CC_NZ, dst+2); + dst = pop_r(dst, RAX); + dst = pop_r(dst, RDX); + dst = mov_ir(dst, VECTOR_INT_DIV_ZERO, SCRATCH2, SZ_D); + dst = mov_ir(dst, inst->address+2, SCRATCH1, SZ_D); + dst = jmp(dst, (uint8_t *)m68k_trap); + *not_zero = dst - (not_zero+1); if (inst->op == M68K_DIVS) { dst = cdq(dst); } else { @@ -3160,15 +3171,16 @@ uint8_t * translate_m68k(uint8_t * dst, m68kinst * inst, x86_68k_options * opts) } else { dst = div_r(dst, SCRATCH2, SZ_D); } - dst = cmp_ir(dst, 0x10000, RAX, SZ_D); + uint8_t * skip_sec_check; if (inst->op == M68K_DIVS) { - uint8_t * skip_sec_check = dst + 1; - dst = jcc(dst, CC_C, dst+2); - dst = cmp_ir(dst, -0x10000, RAX, SZ_D); + dst = cmp_ir(dst, 0x8000, RAX, SZ_D); + skip_sec_check = dst + 1; + dst = jcc(dst, CC_GE, dst+2); + dst = cmp_ir(dst, -0x8000, RAX, SZ_D); norm_off = dst+1; - dst = jcc(dst, CC_LE, dst+2); - *skip_sec_check = dst - (skip_sec_check+1); + dst = jcc(dst, CC_L, dst+2); } else { + dst = cmp_ir(dst, 0x10000, RAX, SZ_D); norm_off = dst+1; dst = jcc(dst, CC_NC, dst+2); } @@ -3190,12 +3202,15 @@ uint8_t * translate_m68k(uint8_t * dst, m68kinst * inst, x86_68k_options * opts) end_off = dst+1; dst = jmp(dst, dst+2); *norm_off = dst - (norm_off + 1); + if (inst->op == M68K_DIVS) { + *skip_sec_check = dst - (skip_sec_check+1); + } dst = pop_r(dst, RAX); dst = pop_r(dst, RDX); dst = mov_ir(dst, 1, FLAG_V, SZ_B); *end_off = dst - (end_off + 1); - dst = mov_ir(dst, 0, FLAG_C, SZ_B); break; + } case M68K_EOR: dst = cycles(dst, BUS); if (src_op.mode == MODE_REG_DIRECT) { |