From 7b0055d742f1679f5b1b1f56e339b11b947f4090 Mon Sep 17 00:00:00 2001 From: Aurelien Jarno Date: Sat, 10 Feb 2018 21:33:39 -0500 Subject: [PATCH] tcg/optimize: fold constant test in tcg_opt_gen_mov Most of the calls to tcg_opt_gen_mov are preceeded by a test to check if the source temp is a constant. Fold that into the tcg_opt_gen_mov function. Backports commit 97a79eb70dd35a24fda87d86196afba5e6f21c5d from qemu --- qemu/tcg/optimize.c | 95 +++++++++++++++++++-------------------------- 1 file changed, 40 insertions(+), 55 deletions(-) diff --git a/qemu/tcg/optimize.c b/qemu/tcg/optimize.c index a1ba2b65..6dfa54aa 100644 --- a/qemu/tcg/optimize.c +++ b/qemu/tcg/optimize.c @@ -184,15 +184,45 @@ static bool temps_are_copies(TCGContext *s, TCGArg arg1, TCGArg arg2) return false; } +static void tcg_opt_gen_movi(TCGContext *s, TCGOp *op, TCGArg *args, + TCGArg dst, TCGArg val) +{ + struct tcg_temp_info *temps = s->temps2; + TCGOpcode new_op = op_to_movi(s, op->opc); + tcg_target_ulong mask; + + op->opc = new_op; + + reset_temp(s, dst); + + temps[dst].state = TCG_TEMP_CONST; + temps[dst].val = val; + mask = val; + if (TCG_TARGET_REG_BITS > 32 && new_op == INDEX_op_mov_i32) { + /* High bits of the destination are now garbage. */ + mask |= ~0xffffffffull; + } + temps[dst].mask = mask; + + args[0] = dst; + args[1] = val; +} + static void tcg_opt_gen_mov(TCGContext *s, TCGOp *op, TCGArg *args, TCGArg dst, TCGArg src) { - if (temps_are_copies(dst, src)) { + if (temps_are_copies(s, dst, src)) { tcg_op_remove(s, op); return; } struct tcg_temp_info *temps = s->temps2; + + if (temps[src].state == TCG_TEMP_CONST) { + tcg_opt_gen_movi(s, op, args, dst, temps[src].val); + return; + } + TCGOpcode new_op = op_to_mov(s, op->opc); tcg_target_ulong mask; @@ -225,29 +255,6 @@ static void tcg_opt_gen_mov(TCGContext *s, TCGOp *op, TCGArg *args, args[1] = src; } -static void tcg_opt_gen_movi(TCGContext *s, TCGOp *op, TCGArg *args, - TCGArg dst, TCGArg val) -{ - struct tcg_temp_info *temps = s->temps2; - TCGOpcode new_op = op_to_movi(s, op->opc); - tcg_target_ulong mask; - - op->opc = new_op; - - reset_temp(s, dst); - temps[dst].state = TCG_TEMP_CONST; - temps[dst].val = val; - mask = val; - if (TCG_TARGET_REG_BITS > 32 && new_op == INDEX_op_mov_i32) { - /* High bits of the destination are now garbage. */ - mask |= ~0xffffffffull; - } - temps[dst].mask = mask; - - args[0] = dst; - args[1] = val; -} - static TCGArg do_constant_folding_2(TCGOpcode op, TCGArg x, TCGArg y) { uint64_t l64, h64; @@ -782,7 +789,8 @@ static void tcg_constant_folding(TCGContext *s) if (temps[args[1]].state != TCG_TEMP_CONST && temps[args[2]].state == TCG_TEMP_CONST && temps[args[2]].val == 0) { - goto do_mov3; + tcg_opt_gen_mov(s, op, args, args[0], args[1]); + continue; } break; CASE_OP_32_64(and): @@ -791,12 +799,10 @@ static void tcg_constant_folding(TCGContext *s) if (temps[args[1]].state != TCG_TEMP_CONST && temps[args[2]].state == TCG_TEMP_CONST && temps[args[2]].val == -1) { - goto do_mov3; + tcg_opt_gen_mov(s, op, args, args[0], args[1]); + continue; } break; - do_mov3: - tcg_opt_gen_mov(s, op, args, args[0], args[1]); - continue; default: break; } @@ -950,12 +956,7 @@ static void tcg_constant_folding(TCGContext *s) } if (affected == 0) { assert(nb_oargs == 1); - if (temps[args[1]].state != TCG_TEMP_CONST) { - tcg_opt_gen_mov(s, op, args, args[0], args[1]); - } else { - tcg_opt_gen_movi(s, op, args, - args[0], temps[args[1]].val); - } + tcg_opt_gen_mov(s, op, args, args[0], args[1]); continue; } @@ -980,12 +981,7 @@ static void tcg_constant_folding(TCGContext *s) CASE_OP_32_64(or): CASE_OP_32_64(and): if (temps_are_copies(s, args[1], args[2])) { - if (temps[args[1]].state != TCG_TEMP_CONST) { - tcg_opt_gen_mov(s, op, args, args[0], args[1]); - } else { - tcg_opt_gen_movi(s, op, args, - args[0], temps[args[1]].val); - } + tcg_opt_gen_mov(s, op, args, args[0], args[1]); continue; } break; @@ -1012,14 +1008,8 @@ static void tcg_constant_folding(TCGContext *s) allocator where needed and possible. Also detect copies. */ switch (opc) { CASE_OP_32_64(mov): - if (temps[args[1]].state != TCG_TEMP_CONST) { - tcg_opt_gen_mov(s, op, args, args[0], args[1]); - break; - } - /* Source argument is constant. Rewrite the operation and - let movi case handle it. */ - args[1] = temps[args[1]].val; - /* fallthrough */ + tcg_opt_gen_mov(s, op, args, args[0], args[1]); + break; CASE_OP_32_64(movi): tcg_opt_gen_movi(s, op, args, args[0], args[1]); break; @@ -1113,12 +1103,7 @@ static void tcg_constant_folding(TCGContext *s) CASE_OP_32_64(movcond): tmp = do_constant_folding_cond(s, opc, args[1], args[2], args[5]); if (tmp != 2) { - if (temps[args[4-tmp]].state == TCG_TEMP_CONST) { - tcg_opt_gen_movi(s, op, args, - args[0], temps[args[4-tmp]].val); - } else { - tcg_opt_gen_mov(s, op, args, args[0], args[4-tmp]); - } + tcg_opt_gen_mov(s, op, args, args[0], args[4-tmp]); break; } goto do_default;