From 8d5f3ca9ccace2374fd73d46fad56decc02e0a44 Mon Sep 17 00:00:00 2001 From: Aurelien Jarno Date: Tue, 18 Sep 2012 19:37:00 +0200 Subject: [PATCH] tcg/optimize: further optimize brcond/movcond/setcond When both argument of brcond/movcond/setcond are the same or when one of the two values is a constant equal to zero, it's possible to do further optimizations. Reviewed-by: Richard Henderson Signed-off-by: Aurelien Jarno Signed-off-by: Michael Roth --- tcg/optimize.c | 127 ++++++++++++++++++++++++++++++++++----------------------- 1 file changed, 76 insertions(+), 51 deletions(-) diff --git a/tcg/optimize.c b/tcg/optimize.c index ceea644..abe016a 100644 --- a/tcg/optimize.c +++ b/tcg/optimize.c @@ -292,58 +292,88 @@ static TCGArg do_constant_folding(TCGOpcode op, TCGArg x, TCGArg y) return res; } +/* Return 2 if the condition can't be simplified, and the result + of the condition (0 or 1) if it can */ static TCGArg do_constant_folding_cond(TCGOpcode op, TCGArg x, TCGArg y, TCGCond c) { - switch (op_bits(op)) { - case 32: + if (temps[x].state == TCG_TEMP_CONST && temps[y].state == TCG_TEMP_CONST) { + switch (op_bits(op)) { + case 32: + switch (c) { + case TCG_COND_EQ: + return (uint32_t)temps[x].val == (uint32_t)temps[y].val; + case TCG_COND_NE: + return (uint32_t)temps[x].val != (uint32_t)temps[y].val; + case TCG_COND_LT: + return (int32_t)temps[x].val < (int32_t)temps[y].val; + case TCG_COND_GE: + return (int32_t)temps[x].val >= (int32_t)temps[y].val; + case TCG_COND_LE: + return (int32_t)temps[x].val <= (int32_t)temps[y].val; + case TCG_COND_GT: + return (int32_t)temps[x].val > (int32_t)temps[y].val; + case TCG_COND_LTU: + return (uint32_t)temps[x].val < (uint32_t)temps[y].val; + case TCG_COND_GEU: + return (uint32_t)temps[x].val >= (uint32_t)temps[y].val; + case TCG_COND_LEU: + return (uint32_t)temps[x].val <= (uint32_t)temps[y].val; + case TCG_COND_GTU: + return (uint32_t)temps[x].val > (uint32_t)temps[y].val; + } + break; + case 64: + switch (c) { + case TCG_COND_EQ: + return (uint64_t)temps[x].val == (uint64_t)temps[y].val; + case TCG_COND_NE: + return (uint64_t)temps[x].val != (uint64_t)temps[y].val; + case TCG_COND_LT: + return (int64_t)temps[x].val < (int64_t)temps[y].val; + case TCG_COND_GE: + return (int64_t)temps[x].val >= (int64_t)temps[y].val; + case TCG_COND_LE: + return (int64_t)temps[x].val <= (int64_t)temps[y].val; + case TCG_COND_GT: + return (int64_t)temps[x].val > (int64_t)temps[y].val; + case TCG_COND_LTU: + return (uint64_t)temps[x].val < (uint64_t)temps[y].val; + case TCG_COND_GEU: + return (uint64_t)temps[x].val >= (uint64_t)temps[y].val; + case TCG_COND_LEU: + return (uint64_t)temps[x].val <= (uint64_t)temps[y].val; + case TCG_COND_GTU: + return (uint64_t)temps[x].val > (uint64_t)temps[y].val; + } + break; + } + } else if (temps_are_copies(x, y)) { switch (c) { - case TCG_COND_EQ: - return (uint32_t)x == (uint32_t)y; - case TCG_COND_NE: - return (uint32_t)x != (uint32_t)y; - case TCG_COND_LT: - return (int32_t)x < (int32_t)y; - case TCG_COND_GE: - return (int32_t)x >= (int32_t)y; - case TCG_COND_LE: - return (int32_t)x <= (int32_t)y; case TCG_COND_GT: - return (int32_t)x > (int32_t)y; case TCG_COND_LTU: - return (uint32_t)x < (uint32_t)y; - case TCG_COND_GEU: - return (uint32_t)x >= (uint32_t)y; - case TCG_COND_LEU: - return (uint32_t)x <= (uint32_t)y; + case TCG_COND_LT: case TCG_COND_GTU: - return (uint32_t)x > (uint32_t)y; - } - break; - case 64: - switch (c) { - case TCG_COND_EQ: - return (uint64_t)x == (uint64_t)y; case TCG_COND_NE: - return (uint64_t)x != (uint64_t)y; - case TCG_COND_LT: - return (int64_t)x < (int64_t)y; + return 0; case TCG_COND_GE: - return (int64_t)x >= (int64_t)y; + case TCG_COND_GEU: case TCG_COND_LE: - return (int64_t)x <= (int64_t)y; - case TCG_COND_GT: - return (int64_t)x > (int64_t)y; + case TCG_COND_LEU: + case TCG_COND_EQ: + return 1; + } + } else if (temps[y].state == TCG_TEMP_CONST && temps[y].val == 0) { + switch (c) { case TCG_COND_LTU: - return (uint64_t)x < (uint64_t)y; + return 0; case TCG_COND_GEU: - return (uint64_t)x >= (uint64_t)y; - case TCG_COND_LEU: - return (uint64_t)x <= (uint64_t)y; - case TCG_COND_GTU: - return (uint64_t)x > (uint64_t)y; + return 1; + default: + return 2; } - break; + } else { + return 2; } fprintf(stderr, @@ -636,11 +666,9 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, args += 3; break; CASE_OP_32_64(setcond): - if (temps[args[1]].state == TCG_TEMP_CONST - && temps[args[2]].state == TCG_TEMP_CONST) { + tmp = do_constant_folding_cond(op, args[1], args[2], args[3]); + if (tmp != 2) { gen_opc_buf[op_index] = op_to_movi(op); - tmp = do_constant_folding_cond(op, temps[args[1]].val, - temps[args[2]].val, args[3]); tcg_opt_gen_movi(gen_args, args[0], tmp); gen_args += 2; } else { @@ -654,10 +682,9 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, args += 4; break; CASE_OP_32_64(brcond): - if (temps[args[0]].state == TCG_TEMP_CONST - && temps[args[1]].state == TCG_TEMP_CONST) { - if (do_constant_folding_cond(op, temps[args[0]].val, - temps[args[1]].val, args[2])) { + tmp = do_constant_folding_cond(op, args[0], args[1], args[2]); + if (tmp != 2) { + if (tmp) { memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info)); gen_opc_buf[op_index] = INDEX_op_br; gen_args[0] = args[3]; @@ -677,10 +704,8 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, args += 4; break; CASE_OP_32_64(movcond): - if (temps[args[1]].state == TCG_TEMP_CONST - && temps[args[2]].state == TCG_TEMP_CONST) { - tmp = do_constant_folding_cond(op, temps[args[1]].val, - temps[args[2]].val, args[5]); + tmp = do_constant_folding_cond(op, args[1], args[2], args[5]); + if (tmp != 2) { if (temps_are_copies(args[0], args[4-tmp])) { gen_opc_buf[op_index] = INDEX_op_nop; } else if (temps[args[4-tmp]].state == TCG_TEMP_CONST) { -- 1.7.12.1