diff options
Diffstat (limited to 'tcg')
| -rw-r--r-- | tcg/optimize.c | 33 |
1 files changed, 26 insertions, 7 deletions
diff --git a/tcg/optimize.c b/tcg/optimize.c index bcd500c6aa..77da2f942a 100644 --- a/tcg/optimize.c +++ b/tcg/optimize.c @@ -166,11 +166,18 @@ static void tcg_opt_gen_mov(TCGContext *s, int op_index, TCGArg *gen_args, TCGOpcode old_op, TCGArg dst, TCGArg src) { TCGOpcode new_op = op_to_mov(old_op); + tcg_target_ulong mask; s->gen_opc_buf[op_index] = new_op; reset_temp(dst); - temps[dst].mask = temps[src].mask; + mask = temps[src].mask; + 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; + assert(temps[src].state != TCG_TEMP_CONST); if (s->temps[src].type == s->temps[dst].type) { @@ -194,13 +201,20 @@ static void tcg_opt_gen_movi(TCGContext *s, int op_index, TCGArg *gen_args, TCGOpcode old_op, TCGArg dst, TCGArg val) { TCGOpcode new_op = op_to_movi(old_op); + tcg_target_ulong mask; s->gen_opc_buf[op_index] = new_op; reset_temp(dst); temps[dst].state = TCG_TEMP_CONST; temps[dst].val = val; - temps[dst].mask = 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; + gen_args[0] = dst; gen_args[1] = val; } @@ -539,7 +553,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, for (op_index = 0; op_index < nb_ops; op_index++) { TCGOpcode op = s->gen_opc_buf[op_index]; const TCGOpDef *def = &tcg_op_defs[op]; - tcg_target_ulong mask, affected; + tcg_target_ulong mask, partmask, affected; int nb_oargs, nb_iargs, nb_args, i; TCGArg tmp; @@ -902,13 +916,18 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, break; } - /* 32-bit ops (non 64-bit ops and non load/store ops) generate 32-bit - results */ + /* 32-bit ops (non 64-bit ops and non load/store ops) generate + 32-bit results. For the result is zero test below, we can + ignore high bits, but for further optimizations we need to + record that the high bits contain garbage. */ + partmask = mask; if (!(def->flags & (TCG_OPF_CALL_CLOBBER | TCG_OPF_64BIT))) { - mask &= 0xffffffffu; + mask |= ~(tcg_target_ulong)0xffffffffu; + partmask &= 0xffffffffu; + affected &= 0xffffffffu; } - if (mask == 0) { + if (partmask == 0) { assert(nb_oargs == 1); tcg_opt_gen_movi(s, op_index, gen_args, op, args[0], 0); args += nb_args; |