diff options
Diffstat (limited to 'backend_x86.c')
| -rw-r--r-- | backend_x86.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/backend_x86.c b/backend_x86.c index 4eca2a5..614df1b 100644 --- a/backend_x86.c +++ b/backend_x86.c @@ -1,5 +1,6 @@ #include "backend.h" #include "gen_x86.h" +#include <string.h> void cycles(cpu_options *opts, uint32_t num) { @@ -28,6 +29,41 @@ void check_cycles_int(cpu_options *opts, uint32_t address) *jmp_off = code->cur - (jmp_off+1); } +void retranslate_calc(cpu_options *opts) +{ + code_info *code = &opts->code; + code_info tmp = *code; + uint8_t cc; + if (opts->limit < 0) { + cmp_ir(code, 1, opts->cycles, SZ_D); + cc = CC_NS; + } else { + cmp_rr(code, opts->cycles, opts->limit, SZ_D); + cc = CC_A; + } + jcc(code, cc, code->cur+2); + opts->move_pc_off = code->cur - tmp.cur; + mov_ir(code, 0x1234, opts->scratch1, SZ_D); + opts->move_pc_size = code->cur - tmp.cur - opts->move_pc_off; + *code = tmp; +} + +void patch_for_retranslate(cpu_options *opts, code_ptr native_address, code_ptr handler) +{ + if (!is_mov_ir(native_address)) { + //instruction is not already patched for either retranslation or a breakpoint + //copy original mov_ir instruction containing PC to beginning of native code area + memmove(native_address, native_address + opts->move_pc_off, opts->move_pc_size); + } + //jump to the retranslation handler + code_info tmp = { + .cur = native_address + opts->move_pc_size, + .last = native_address + 256, + .stack_off = 0 + }; + jmp(&tmp, handler); +} + void check_cycles(cpu_options * opts) { code_info *code = &opts->code; |