diff options
| -rw-r--r-- | tcg/optimize.c | 56 |
1 files changed, 24 insertions, 32 deletions
diff --git a/tcg/optimize.c b/tcg/optimize.c index edb2b0e..ff4ddb2 100644 --- a/tcg/optimize.c +++ b/tcg/optimize.c @@ -388,6 +388,23 @@ static TCGArg do_constant_folding_cond(TCGOpcode op, TCGArg x, tcg_abort(); } +static bool swap_commutative(TCGArg dest, TCGArg *p1, TCGArg *p2) +{ + TCGArg a1 = *p1, a2 = *p2; + int sum = 0; + sum += temps[a1].state == TCG_TEMP_CONST; + sum -= temps[a2].state == TCG_TEMP_CONST; + + /* Prefer the constant in second argument, and then the form + op a, a, b, which is better handled on non-RISC hosts. */ + if (sum > 0 || (sum == 0 && dest == a2)) { + *p1 = a2; + *p2 = a1; + return true; + } + return false; +} + /* Propagate constants and copies, fold constant expressions. */ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, TCGArg *args, TCGOpDef *tcg_op_defs) @@ -397,7 +414,6 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, const TCGOpDef *def; TCGArg *gen_args; TCGArg tmp; - TCGCond cond; /* Array VALS has an element for each temp. If this temp holds a constant then its value is kept in VALS' element. @@ -440,52 +456,28 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, CASE_OP_32_64(eqv): CASE_OP_32_64(nand): CASE_OP_32_64(nor): - /* Prefer the constant in second argument, and then the form - op a, a, b, which is better handled on non-RISC hosts. */ - if (temps[args[1]].state == TCG_TEMP_CONST || (args[0] == args[2] - && temps[args[2]].state != TCG_TEMP_CONST)) { - tmp = args[1]; - args[1] = args[2]; - args[2] = tmp; - } + swap_commutative(args[0], &args[1], &args[2]); break; CASE_OP_32_64(brcond): - if (temps[args[0]].state == TCG_TEMP_CONST - && temps[args[1]].state != TCG_TEMP_CONST) { - tmp = args[0]; - args[0] = args[1]; - args[1] = tmp; + if (swap_commutative(-1, &args[0], &args[1])) { args[2] = tcg_swap_cond(args[2]); } break; CASE_OP_32_64(setcond): - if (temps[args[1]].state == TCG_TEMP_CONST - && temps[args[2]].state != TCG_TEMP_CONST) { - tmp = args[1]; - args[1] = args[2]; - args[2] = tmp; + if (swap_commutative(args[0], &args[1], &args[2])) { args[3] = tcg_swap_cond(args[3]); } break; CASE_OP_32_64(movcond): - cond = args[5]; - if (temps[args[1]].state == TCG_TEMP_CONST - && temps[args[2]].state != TCG_TEMP_CONST) { - tmp = args[1]; - args[1] = args[2]; - args[2] = tmp; - cond = tcg_swap_cond(cond); + if (swap_commutative(-1, &args[1], &args[2])) { + args[5] = tcg_swap_cond(args[5]); } /* For movcond, we canonicalize the "false" input reg to match the destination reg so that the tcg backend can implement a "move if true" operation. */ - if (args[0] == args[3]) { - tmp = args[3]; - args[3] = args[4]; - args[4] = tmp; - cond = tcg_invert_cond(cond); + if (swap_commutative(args[0], &args[4], &args[3])) { + args[5] = tcg_invert_cond(args[5]); } - args[5] = cond; default: break; } |