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free global values from local registers; tune spill cost calculation;

cache-refactoring
Aleksey Demakov 19 years ago
parent
4afe9af964
commit
91a53d22e7
2 changed files with 85 additions and 37 deletions
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  1. 11
      ChangeLog
  2. 111
      jit/jit-reg-alloc.c

11
ChangeLog
View File

@ -1,3 +1,14 @@
2006-05-27 Aleksey Demakov <ademakov@gmail.com>
* jit/jit-reg-alloc.c (free_value, save_value): the value that has
a global register and is also associated with a local register
needs to be unbound from the local one.
* jit/jit-reg-alloc.c (compute_spill_cost): assume that the spill
cost for clean values is not zero. This keeps them in registers
as long as there are free registers and thus reduces the number of
loads.
2006-05-25 Aleksey Demakov <ademakov@gmail.com>
* jit/jit-reg-alloc.c (use_cheapest_register): fix cost calculation

111
jit/jit-reg-alloc.c
View File

@ -1641,6 +1641,12 @@ void _jit_regs_get_reg_pair(jit_gencode_t gen, int not_this1, int not_this2,
/* The cost value that precludes using the register in question. */
#define COST_TOO_MUCH 1000000
#define COST_COPY 4
#define COST_SPILL_DIRTY 16
#define COST_SPILL_DIRTY_GLOBAL 2
#define COST_SPILL_CLEAN 1
#define COST_SPILL_CLEAN_GLOBAL 1
/* Value usage flags. */
#define VALUE_INPUT 1
#define VALUE_USED 2
@ -2077,28 +2083,28 @@ collect_register_info(jit_gencode_t gen, _jit_regs_t *regs, int index)
return 1;
}
if(desc->value->has_global_register)
{
if(desc->value->global_reg != desc->reg
&& !(desc->value->in_register && desc->value->reg == desc->reg))
{
desc->copy = 1;
}
}
else
if(index > 0 || regs->ternary)
{
if(!desc->value->in_register)
if(desc->value->has_global_register)
{
desc->load = 1;
if(desc->value->global_reg != desc->reg
&& !(desc->value->in_register && desc->value->reg == desc->reg))
{
desc->copy = 1;
}
}
else if(desc->value->reg != desc->reg)
else
{
desc->copy = 1;
if(!desc->value->in_register)
{
desc->load = 1;
}
else if(desc->value->reg != desc->reg)
{
desc->copy = 1;
}
}
}
if(index > 0 || regs->ternary)
{
if(desc->value->is_constant)
{
desc->kill = 1;
@ -2178,6 +2184,11 @@ collect_register_info(jit_gencode_t gen, _jit_regs_t *regs, int index)
printf("value = ");
jit_dump_value(stdout, jit_value_get_function(desc->value), desc->value, 0);
printf("\n");
printf("value->in_register = %d\n", desc->value->in_register);
printf("value->reg = %d\n", desc->value->reg);
printf("value->in_global_register = %d\n", desc->value->in_global_register);
printf("value->global_reg = %d\n", desc->value->global_reg);
printf("value->in_frame = %d\n", desc->value->in_frame);
printf("reg = %d\n", desc->reg);
printf("other_reg = %d\n", desc->other_reg);
printf("live = %d\n", desc->live);
@ -2282,16 +2293,24 @@ compute_spill_cost(jit_gencode_t gen, _jit_regs_t *regs, int reg, int other_reg)
}
if(value->has_global_register)
{
if(!value->in_global_register)
if(value->in_global_register)
{
cost += 1;
cost += COST_SPILL_CLEAN_GLOBAL;
}
else
{
cost += COST_SPILL_DIRTY_GLOBAL;
}
}
else
{
if(!value->in_frame)
if(value->in_frame)
{
cost += COST_SPILL_CLEAN;
}
else
{
cost += 10;
cost += COST_SPILL_DIRTY;
}
}
}
@ -2388,10 +2407,10 @@ use_cheapest_register(jit_gencode_t gen, _jit_regs_t *regs, int index, jit_regus
int type;
int need_pair;
int reg, other_reg;
int cost, copy_cost;
int suitable_reg;
int suitable_cost;
int suitable_age;
int move, cost;
if(index >= 0)
{
@ -2443,7 +2462,7 @@ use_cheapest_register(jit_gencode_t gen, _jit_regs_t *regs, int index, jit_regus
{
continue;
}
move = 0;
copy_cost = 0;
cost = compute_spill_cost(gen, regs, reg, -1);
}
else if(desc->value->has_global_register)
@ -2454,7 +2473,7 @@ use_cheapest_register(jit_gencode_t gen, _jit_regs_t *regs, int index, jit_regus
{
continue;
}
move = ((output | desc->value->in_global_register) == 0);
copy_cost = ((output | desc->value->in_global_register) == 0);
cost = 0;
}
else if(jit_reg_is_used(gen->permanent, reg))
@ -2467,7 +2486,7 @@ use_cheapest_register(jit_gencode_t gen, _jit_regs_t *regs, int index, jit_regus
}
else if(desc->value->in_register && reg == desc->value->reg)
{
move = ((output | desc->value->in_global_register) != 0);
copy_cost = ((output | desc->value->in_global_register) != 0);
if(clobbers_register(gen, regs, index, reg, -1))
{
cost = compute_spill_cost(gen, regs, reg, -1);
@ -2479,7 +2498,7 @@ use_cheapest_register(jit_gencode_t gen, _jit_regs_t *regs, int index, jit_regus
}
else
{
move = 1;
copy_cost = 1;
cost = compute_spill_cost(gen, regs, reg, -1);
}
}
@ -2522,35 +2541,41 @@ use_cheapest_register(jit_gencode_t gen, _jit_regs_t *regs, int index, jit_regus
|| (other_reg >= 0
&& jit_reg_is_used(regs->clobber, other_reg))))
{
move = 0;
copy_cost = 0;
cost = compute_spill_cost(gen, regs, reg, other_reg);
}
else
{
move = 0;
copy_cost = 0;
cost = 0;
}
}
else
{
move = 1;
copy_cost = 1;
cost = compute_spill_cost(gen, regs, reg, other_reg);
}
}
else
{
move = 0;
copy_cost = 0;
cost = compute_spill_cost(gen, regs, reg, other_reg);
}
}
if((move + cost) < suitable_cost
|| (cost > 0 && (move + cost) == suitable_cost
#if COST_COPY != 1
if(copy_cost)
{
copy_cost = COST_COPY;
}
#endif
if((cost + copy_cost) < suitable_cost
|| (cost > 0 && (cost + copy_cost) == suitable_cost
&& gen->contents[reg].age < suitable_age))
{
/* This is the oldest suitable register of this type */
suitable_reg = reg;
suitable_cost = move + cost;
suitable_cost = cost + copy_cost;
suitable_age = gen->contents[reg].age;
}
}
@ -3098,7 +3123,7 @@ free_value(jit_gencode_t gen, jit_value_t value, int reg, int other_reg)
#endif
/* Never free global registers. */
if(value->has_global_register)
if(value->has_global_register && value->global_reg == reg)
{
return;
}
@ -3130,11 +3155,21 @@ save_value(jit_gencode_t gen, jit_value_t value, int reg, int other_reg, int fre
/* First take care of values that reside in global registers. */
if(value->has_global_register)
{
if(value->global_reg != reg && !value->in_global_register)
/* Never free global registers. */
if(value->global_reg == reg)
{
return;
}
if(!value->in_global_register)
{
_jit_gen_spill_reg(gen, reg, other_reg, value);
value->in_global_register = 1;
}
if(free)
{
unbind_value(gen, value, reg, other_reg);
}
return;
}
@ -3534,7 +3569,8 @@ commit_input_value(jit_gencode_t gen, _jit_regs_t *regs, int index)
printf("\n");
printf("value->in_register = %d\n", desc->value->in_register);
printf("value->reg = %d\n", desc->value->reg);
printf("value->in_gloable_register = %d\n", desc->value->in_global_register);
printf("value->in_global_register = %d\n", desc->value->in_global_register);
printf("value->global_reg = %d\n", desc->value->global_reg);
printf("value->in_frame = %d\n", desc->value->in_frame);
#endif
}
@ -3581,7 +3617,8 @@ commit_output_value(jit_gencode_t gen, _jit_regs_t *regs)
printf("\n");
printf("value->in_register = %d\n", desc->value->in_register);
printf("value->reg = %d\n", desc->value->reg);
printf("value->in_gloable_register = %d\n", desc->value->in_global_register);
printf("value->in_global_register = %d\n", desc->value->in_global_register);
printf("value->global_reg = %d\n", desc->value->global_reg);
printf("value->in_frame = %d\n", desc->value->in_frame);
#endif
}
@ -4181,7 +4218,7 @@ _jit_regs_commit(jit_gencode_t gen, _jit_regs_t *regs)
}
#ifdef JIT_REG_DEBUG
dump_regs(gen, "enter _jit_regs_commit");
dump_regs(gen, "leave _jit_regs_commit");
#endif
}

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