diff options
Diffstat (limited to 'tcg/optimize.c')
| -rw-r--r-- | tcg/optimize.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/tcg/optimize.c b/tcg/optimize.c index b9a7da920f..ceea6441bc 100644 --- a/tcg/optimize.c +++ b/tcg/optimize.c @@ -540,6 +540,22 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, break; } + /* Simplify expression for "op r, a, a => movi r, 0" cases */ + switch (op) { + CASE_OP_32_64(sub): + CASE_OP_32_64(xor): + if (temps_are_copies(args[1], args[2])) { + gen_opc_buf[op_index] = op_to_movi(op); + tcg_opt_gen_movi(gen_args, args[0], 0); + gen_args += 2; + args += 3; + continue; + } + break; + default: + break; + } + /* Propagate constants through copy operations and do constant folding. Constants will be substituted to arguments by register allocator where needed and possible. Also detect copies. */ |