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gmqcc/ir.c
Wolfgang (Blub) Bumiller 522738de48 Adding liferange-calculation used later for templ-allocateion
2012-04-25 17:27:48 +02:00

1230 lines
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#include <stdlib.h>
#include <string.h>
#include "ir.h"
/***********************************************************************
*IR Builder
*/
ir_builder* ir_builder_new(const char *modulename)
{
ir_builder* self;
self = (ir_builder*)mem_a(sizeof(*self));
MEM_VECTOR_INIT(self, functions);
MEM_VECTOR_INIT(self, globals);
self->name = NULL;
ir_builder_set_name(self, modulename);
/* globals which always exist */
/* for now we give it a vector size */
ir_builder_create_global(self, "OFS_RETURN", qc_variant);
return self;
}
MEM_VEC_FUNCTIONS(ir_builder, ir_value*, globals)
MEM_VECTOR_FUNCTIONS(ir_builder, ir_function*, functions)
void ir_builder_delete(ir_builder* self)
{
size_t i;
mem_d((void*)self->name);
for (i = 0; i != self->functions_count; ++i) {
ir_function_delete(self->functions[i]);
}
MEM_VECTOR_CLEAR(self, functions);
for (i = 0; i != self->globals_count; ++i) {
ir_value_delete(self->globals[i]);
}
MEM_VECTOR_CLEAR(self, globals);
mem_d(self);
}
void ir_builder_set_name(ir_builder *self, const char *name)
{
if (self->name)
mem_d((void*)self->name);
self->name = util_strdup(name);
}
ir_function* ir_builder_get_function(ir_builder *self, const char *name)
{
size_t i;
for (i = 0; i < self->functions_count; ++i) {
if (!strcmp(name, self->functions[i]->name))
return self->functions[i];
}
return NULL;
}
ir_function* ir_builder_create_function(ir_builder *self, const char *name)
{
ir_function *fn = ir_builder_get_function(self, name);
if (fn) {
return NULL;
}
fn = ir_function_new(self);
ir_function_set_name(fn, name);
ir_builder_functions_add(self, fn);
return fn;
}
ir_value* ir_builder_get_global(ir_builder *self, const char *name)
{
size_t i;
for (i = 0; i < self->globals_count; ++i) {
if (!strcmp(self->globals[i]->name, name))
return self->globals[i];
}
return NULL;
}
ir_value* ir_builder_create_global(ir_builder *self, const char *name, int vtype)
{
ir_value *ve = ir_builder_get_global(self, name);
if (ve) {
return NULL;
}
ve = ir_value_var(name, store_global, vtype);
ir_builder_globals_add(self, ve);
return ve;
}
/***********************************************************************
*IR Function
*/
void ir_function_naive_phi(ir_function*);
void ir_function_enumerate(ir_function*);
void ir_function_calculate_liferanges(ir_function*);
ir_function* ir_function_new(ir_builder* owner)
{
ir_function *self;
self = (ir_function*)mem_a(sizeof(*self));
self->owner = owner;
self->context.file = "<@no context>";
self->context.line = 0;
self->retype = qc_void;
MEM_VECTOR_INIT(self, params);
MEM_VECTOR_INIT(self, blocks);
MEM_VECTOR_INIT(self, values);
MEM_VECTOR_INIT(self, locals);
ir_function_set_name(self, "<@unnamed>");
self->run_id = 0;
return self;
}
MEM_VECTOR_FUNCTIONS(ir_function, ir_value*, values)
MEM_VECTOR_FUNCTIONS(ir_function, ir_block*, blocks)
MEM_VECTOR_FUNCTIONS(ir_function, ir_value*, locals)
void ir_function_set_name(ir_function *self, const char *name)
{
if (self->name)
mem_d((void*)self->name);
self->name = util_strdup(name);
}
void ir_function_delete(ir_function *self)
{
size_t i;
mem_d((void*)self->name);
for (i = 0; i != self->blocks_count; ++i)
ir_block_delete(self->blocks[i]);
MEM_VECTOR_CLEAR(self, blocks);
MEM_VECTOR_CLEAR(self, params);
for (i = 0; i != self->values_count; ++i)
ir_value_delete(self->values[i]);
MEM_VECTOR_CLEAR(self, values);
for (i = 0; i != self->locals_count; ++i)
ir_value_delete(self->locals[i]);
MEM_VECTOR_CLEAR(self, locals);
mem_d(self);
}
void ir_function_collect_value(ir_function *self, ir_value *v)
{
ir_function_values_add(self, v);
}
ir_block* ir_function_create_block(ir_function *self, const char *label)
{
ir_block* bn = ir_block_new(self, label);
memcpy(&bn->context, &self->context, sizeof(self->context));
ir_function_blocks_add(self, bn);
return bn;
}
void ir_function_finalize(ir_function *self)
{
ir_function_naive_phi(self);
ir_function_enumerate(self);
ir_function_calculate_liferanges(self);
}
ir_value* ir_function_get_local(ir_function *self, const char *name)
{
size_t i;
for (i = 0; i < self->locals_count; ++i) {
if (!strcmp(self->locals[i]->name, name))
return self->locals[i];
}
return NULL;
}
ir_value* ir_function_create_local(ir_function *self, const char *name, int vtype)
{
ir_value *ve = ir_function_get_local(self, name);
if (ve) {
return NULL;
}
ve = ir_value_var(name, store_local, vtype);
ir_function_locals_add(self, ve);
return ve;
}
/***********************************************************************
*IR Block
*/
ir_block* ir_block_new(ir_function* owner, const char *name)
{
ir_block *self;
self = (ir_block*)mem_a(sizeof(*self));
self->owner = owner;
self->context.file = "<@no context>";
self->context.line = 0;
self->final = false;
MEM_VECTOR_INIT(self, instr);
MEM_VECTOR_INIT(self, entries);
MEM_VECTOR_INIT(self, exits);
self->label = NULL;
ir_block_set_label(self, name);
self->eid = 0;
self->is_return = false;
self->run_id = 0;
MEM_VECTOR_INIT(self, living);
return self;
}
MEM_VECTOR_FUNCTIONS(ir_block, ir_instr*, instr)
MEM_VECTOR_FUNCTIONS_ALL(ir_block, ir_block*, entries)
MEM_VECTOR_FUNCTIONS_ALL(ir_block, ir_block*, exits)
MEM_VECTOR_FUNCTIONS_ALL(ir_block, ir_value*, living)
void ir_block_delete(ir_block* self)
{
size_t i;
mem_d((void*)self->label);
for (i = 0; i != self->instr_count; ++i)
ir_instr_delete(self->instr[i]);
MEM_VECTOR_CLEAR(self, instr);
MEM_VECTOR_CLEAR(self, entries);
MEM_VECTOR_CLEAR(self, exits);
MEM_VECTOR_CLEAR(self, living);
mem_d(self);
}
void ir_block_set_label(ir_block *self, const char *name)
{
if (self->label)
mem_d((void*)self->label);
self->label = util_strdup(name);
}
/***********************************************************************
*IR Instructions
*/
ir_instr* ir_instr_new(ir_block* owner, int op)
{
ir_instr *self;
self = (ir_instr*)mem_a(sizeof(*self));
self->owner = owner;
self->context.file = "<@no context>";
self->context.line = 0;
self->opcode = op;
self->_ops[0] = NULL;
self->_ops[1] = NULL;
self->_ops[2] = NULL;
self->bops[0] = NULL;
self->bops[1] = NULL;
MEM_VECTOR_INIT(self, phi);
self->eid = 0;
return self;
}
MEM_VECTOR_FUNCTIONS(ir_instr, ir_phi_entry_t, phi)
void ir_instr_delete(ir_instr *self)
{
ir_instr_op(self, 0, NULL, false);
ir_instr_op(self, 1, NULL, false);
ir_instr_op(self, 2, NULL, false);
MEM_VECTOR_CLEAR(self, phi);
mem_d(self);
}
void ir_instr_op(ir_instr *self, int op, ir_value *v, qbool writing)
{
if (self->_ops[op]) {
if (writing)
ir_value_writes_add(self->_ops[op], self);
else
ir_value_reads_add(self->_ops[op], self);
}
if (v) {
if (writing)
ir_value_writes_add(v, self);
else
ir_value_reads_add(v, self);
}
self->_ops[op] = v;
}
/***********************************************************************
*IR Value
*/
ir_value* ir_value_var(const char *name, int storetype, int vtype)
{
ir_value *self;
self = (ir_value*)mem_a(sizeof(*self));
self->vtype = vtype;
self->store = storetype;
MEM_VECTOR_INIT(self, reads);
MEM_VECTOR_INIT(self, writes);
self->has_constval = false;
self->context.file = "<@no context>";
self->context.line = 0;
self->name = NULL;
ir_value_set_name(self, name);
MEM_VECTOR_INIT(self, life);
return self;
}
MEM_VECTOR_FUNCTIONS(ir_value, ir_life_entry_t, life)
MEM_VECTOR_FUNCTIONS(ir_value, ir_instr*, reads)
MEM_VECTOR_FUNCTIONS(ir_value, ir_instr*, writes)
ir_value* ir_value_out(ir_function *owner, const char *name, int storetype, int vtype)
{
ir_value *v = ir_value_var(name, storetype, vtype);
ir_function_collect_value(owner, v);
return v;
}
void ir_value_delete(ir_value* self)
{
mem_d((void*)self->name);
if (self->has_constval)
{
if (self->vtype == qc_string)
mem_d((void*)self->cvalue.vstring);
}
MEM_VECTOR_CLEAR(self, reads);
MEM_VECTOR_CLEAR(self, writes);
MEM_VECTOR_CLEAR(self, life);
mem_d(self);
}
void ir_value_set_name(ir_value *self, const char *name)
{
if (self->name)
mem_d((void*)self->name);
self->name = util_strdup(name);
}
qbool ir_value_set_float(ir_value *self, float f)
{
if (self->vtype != qc_float)
return false;
self->cvalue.vfloat = f;
self->has_constval = true;
return true;
}
qbool ir_value_set_vector(ir_value *self, qc_vec_t v)
{
if (self->vtype != qc_vector)
return false;
self->cvalue.vvec = v;
self->has_constval = true;
return true;
}
qbool ir_value_set_string(ir_value *self, const char *str)
{
if (self->vtype != qc_string)
return false;
self->cvalue.vstring = util_strdup(str);
self->has_constval = true;
return true;
}
qbool ir_value_set_int(ir_value *self, int i)
{
if (self->vtype != qc_int)
return false;
self->cvalue.vint = i;
self->has_constval = true;
return true;
}
qbool ir_value_lives(ir_value *self, size_t at)
{
size_t i;
for (i = 0; i < self->life_count; ++i)
{
ir_life_entry_t *life = &self->life[i];
if (life->start <= at && at <= life->end)
return true;
if (life->start > at) /* since it's ordered */
return false;
}
return false;
}
void ir_value_life_insert(ir_value *self, size_t idx, ir_life_entry_t e)
{
size_t k;
ir_value_life_add(self, e); /* naive... */
for (k = self->life_count-1; k > idx; --k)
self->life[k] = self->life[k-1];
self->life[idx] = e;
}
qbool ir_value_life_merge(ir_value *self, size_t s)
{
size_t i;
ir_life_entry_t *life = NULL;
ir_life_entry_t *before = NULL;
ir_life_entry_t new_entry;
/* Find the first range >= s */
for (i = 0; i < self->life_count; ++i)
{
before = life;
life = &self->life[i];
if (life->start > s)
break;
}
/* nothing found? append */
if (i == self->life_count) {
if (life && life->end+1 == s)
{
/* previous life range can be merged in */
life->end++;
return true;
}
if (life && life->end >= s)
return false;
ir_life_entry_t e;
e.start = e.end = s;
ir_value_life_add(self, e);
return true;
}
/* found */
if (before)
{
if (before->end + 1 == s &&
life->start - 1 == s)
{
/* merge */
before->end = life->end;
ir_value_life_remove(self, i);
return true;
}
if (before->end + 1 == s)
{
/* extend before */
before->end++;
return true;
}
/* already contained */
if (before->end >= s)
return false;
}
/* extend */
if (life->start - 1 == s)
{
life->start--;
return true;
}
/* insert a new entry */
new_entry.start = new_entry.end = s;
ir_value_life_insert(self, i, new_entry);
return true;
}
/***********************************************************************
*IR main operations
*/
qbool ir_block_create_store_op(ir_block *self, int op, ir_value *target, ir_value *what)
{
if (target->store == store_value) {
fprintf(stderr, "cannot store to an SSA value\n");
return false;
} else {
ir_instr *in = ir_instr_new(self, op);
ir_instr_op(in, 0, target, true);
ir_instr_op(in, 1, what, false);
ir_block_instr_add(self, in);
return true;
}
}
qbool ir_block_create_store(ir_block *self, ir_value *target, ir_value *what)
{
int op = 0;
int vtype;
if (target->vtype == qc_variant)
vtype = what->vtype;
else
vtype = target->vtype;
switch (vtype) {
case qc_float:
if (what->vtype == qc_int)
op = INSTR_CONV_ITOF;
else
op = INSTR_STORE_F;
break;
case qc_vector:
op = INSTR_STORE_V;
break;
case qc_entity:
op = INSTR_STORE_ENT;
break;
case qc_string:
op = INSTR_STORE_S;
break;
case qc_int:
if (what->vtype == qc_int)
op = INSTR_CONV_FTOI;
else
op = INSTR_STORE_I;
break;
case qc_pointer:
op = INSTR_STORE_I;
break;
}
return ir_block_create_store_op(self, op, target, what);
}
void ir_block_create_return(ir_block *self, ir_value *v)
{
ir_instr *in;
if (self->final) {
fprintf(stderr, "block already ended (%s)\n", self->_label);
return;
}
self->final = true;
self->is_return = true;
in = ir_instr_new(self, INSTR_RETURN);
ir_instr_op(in, 0, v, false);
ir_block_instr_add(self, in);
}
void ir_block_create_if(ir_block *self, ir_value *v,
ir_block *ontrue, ir_block *onfalse)
{
ir_instr *in;
if (self->final) {
fprintf(stderr, "block already ended (%s)\n", self->_label);
return;
}
self->final = true;
//in = ir_instr_new(self, (v->vtype == qc_string ? INSTR_IF_S : INSTR_IF_F));
in = ir_instr_new(self, VINSTR_COND);
ir_instr_op(in, 0, v, false);
in->bops[0] = ontrue;
in->bops[1] = onfalse;
ir_block_instr_add(self, in);
ir_block_exits_add(self, ontrue);
ir_block_exits_add(self, onfalse);
ir_block_entries_add(ontrue, self);
ir_block_entries_add(onfalse, self);
}
void ir_block_create_jump(ir_block *self, ir_block *to)
{
ir_instr *in;
if (self->final) {
fprintf(stderr, "block already ended (%s)\n", self->_label);
return;
}
self->final = true;
in = ir_instr_new(self, VINSTR_JUMP);
in->bops[0] = to;
ir_block_instr_add(self, in);
ir_block_exits_add(self, to);
ir_block_entries_add(to, self);
}
void ir_block_create_goto(ir_block *self, ir_block *to)
{
ir_instr *in;
if (self->final) {
fprintf(stderr, "block already ended (%s)\n", self->_label);
return;
}
self->final = true;
in = ir_instr_new(self, INSTR_GOTO);
in->bops[0] = to;
ir_block_instr_add(self, in);
ir_block_exits_add(self, to);
ir_block_entries_add(to, self);
}
ir_instr* ir_block_create_phi(ir_block *self, const char *label, int ot)
{
ir_value *out;
ir_instr *in;
in = ir_instr_new(self, VINSTR_PHI);
out = ir_value_out(self->owner, label, store_local, ot);
ir_instr_op(in, 0, out, true);
ir_block_instr_add(self, in);
return in;
}
ir_value* ir_phi_value(ir_instr *self)
{
return self->_ops[0];
}
void ir_phi_add(ir_instr* self, ir_block *b, ir_value *v)
{
ir_phi_entry_t pe;
if (!ir_block_entries_find(self->owner, b, NULL)) {
/* Must not be possible to cause this, otherwise the AST
* is doing something wrong.
*/
fprintf(stderr, "Invalid entry block for PHI\n");
abort();
}
pe.value = v;
pe.from = b;
ir_value_reads_add(v, self);
ir_instr_phi_add(self, pe);
}
/* binary op related code */
ir_value* ir_block_create_binop(ir_block *self,
const char *label, int opcode,
ir_value *left, ir_value *right)
{
int ot = qc_void;
switch (opcode) {
case INSTR_ADD_F:
case INSTR_SUB_F:
case INSTR_DIV_F:
case INSTR_MUL_F:
case INSTR_MUL_V:
case INSTR_AND:
case INSTR_OR:
case INSTR_AND_I:
case INSTR_AND_IF:
case INSTR_AND_FI:
case INSTR_OR_I:
case INSTR_OR_IF:
case INSTR_OR_FI:
case INSTR_BITAND:
case INSTR_BITOR:
case INSTR_SUB_S: /* -- offset of string as float */
case INSTR_MUL_IF:
case INSTR_MUL_FI:
case INSTR_DIV_IF:
case INSTR_DIV_FI:
case INSTR_BITOR_IF:
case INSTR_BITOR_FI:
case INSTR_BITAND_FI:
case INSTR_BITAND_IF:
case INSTR_EQ_I:
case INSTR_NE_I:
ot = qc_float;
break;
case INSTR_ADD_I:
case INSTR_ADD_IF:
case INSTR_ADD_FI:
case INSTR_SUB_I:
case INSTR_SUB_FI:
case INSTR_SUB_IF:
case INSTR_MUL_I:
case INSTR_DIV_I:
case INSTR_BITAND_I:
case INSTR_BITOR_I:
case INSTR_XOR_I:
case INSTR_RSHIFT_I:
case INSTR_LSHIFT_I:
ot = qc_int;
break;
case INSTR_ADD_V:
case INSTR_SUB_V:
case INSTR_MUL_VF:
case INSTR_MUL_FV:
case INSTR_DIV_VF:
case INSTR_MUL_IV:
case INSTR_MUL_VI:
ot = qc_vector;
break;
case INSTR_ADD_SF:
ot = qc_pointer;
break;
default:
// ranges:
/* boolean operations result in floats */
if (opcode >= INSTR_EQ_F && opcode <= INSTR_GT)
ot = qc_float;
else if (opcode >= INSTR_LE && opcode <= INSTR_GT)
ot = qc_float;
else if (opcode >= INSTR_LE_I && opcode <= INSTR_EQ_FI)
ot = qc_float;
break;
};
if (ot == qc_void) {
fprintf(stderr, "binop %i (%s)\n", opcode, qc_opname(opcode));
abort();
return NULL;
}
ir_value *out = ir_value_out(self->owner, label, store_local, ot);
ir_instr *in = ir_instr_new(self, opcode);
ir_instr_op(in, 0, out, true);
ir_instr_op(in, 1, left, false);
ir_instr_op(in, 2, right, false);
ir_block_instr_add(self, in);
return out;
}
ir_value* ir_block_create_add(ir_block *self,
const char *label,
ir_value *left, ir_value *right)
{
int op = 0;
int l = left->vtype;
int r = right->vtype;
if (l == r) {
switch (l) {
default:
return NULL;
case qc_float:
op = INSTR_ADD_F;
break;
case qc_int:
op = INSTR_ADD_I;
break;
case qc_vector:
op = INSTR_ADD_V;
break;
}
} else {
if ( (l == qc_float && r == qc_int) )
op = INSTR_ADD_FI;
else if ( (l == qc_int && r == qc_float) )
op = INSTR_ADD_IF;
else
return NULL;
}
return ir_block_create_binop(self, label, op, left, right);
}
ir_value* ir_block_create_sub(ir_block *self,
const char *label,
ir_value *left, ir_value *right)
{
int op = 0;
int l = left->vtype;
int r = right->vtype;
if (l == r) {
switch (l) {
default:
return NULL;
case qc_float:
op = INSTR_SUB_F;
break;
case qc_int:
op = INSTR_SUB_I;
break;
case qc_vector:
op = INSTR_SUB_V;
break;
}
} else {
if ( (l == qc_float && r == qc_int) )
op = INSTR_SUB_FI;
else if ( (l == qc_int && r == qc_float) )
op = INSTR_SUB_IF;
else
return NULL;
}
return ir_block_create_binop(self, label, op, left, right);
}
ir_value* ir_block_create_mul(ir_block *self,
const char *label,
ir_value *left, ir_value *right)
{
int op = 0;
int l = left->vtype;
int r = right->vtype;
if (l == r) {
switch (l) {
default:
return NULL;
case qc_float:
op = INSTR_MUL_F;
break;
case qc_int:
op = INSTR_MUL_I;
break;
case qc_vector:
op = INSTR_MUL_V;
break;
}
} else {
if ( (l == qc_float && r == qc_int) )
op = INSTR_MUL_FI;
else if ( (l == qc_int && r == qc_float) )
op = INSTR_MUL_IF;
else if ( (l == qc_vector && r == qc_float) )
op = INSTR_MUL_VF;
else if ( (l == qc_float && r == qc_vector) )
op = INSTR_MUL_FV;
else if ( (l == qc_vector && r == qc_int) )
op = INSTR_MUL_VI;
else if ( (l == qc_int && r == qc_vector) )
op = INSTR_MUL_IV;
else
return NULL;
}
return ir_block_create_binop(self, label, op, left, right);
}
ir_value* ir_block_create_div(ir_block *self,
const char *label,
ir_value *left, ir_value *right)
{
int op = 0;
int l = left->vtype;
int r = right->vtype;
if (l == r) {
switch (l) {
default:
return NULL;
case qc_float:
op = INSTR_DIV_F;
break;
case qc_int:
op = INSTR_DIV_I;
break;
}
} else {
if ( (l == qc_float && r == qc_int) )
op = INSTR_DIV_FI;
else if ( (l == qc_int && r == qc_float) )
op = INSTR_DIV_IF;
else if ( (l == qc_vector && r == qc_float) )
op = INSTR_DIV_VF;
else
return NULL;
}
return ir_block_create_binop(self, label, op, left, right);
}
/* PHI resolving breaks the SSA, and must thus be the last
* step before life-range calculation.
*/
static void ir_block_naive_phi(ir_block *self);
void ir_function_naive_phi(ir_function *self)
{
size_t i;
for (i = 0; i < self->blocks_count; ++i)
ir_block_naive_phi(self->blocks[i]);
}
static void ir_naive_phi_emit_store(ir_block *block, size_t iid, ir_value *old, ir_value *what)
{
ir_instr *instr;
size_t i;
/* create a store */
ir_block_create_store(block, old, what);
/* we now move it up */
instr = block->instr[block->instr_count-1];
for (i = block->instr_count; i > iid; --i)
block->instr[i] = block->instr[i-1];
block->instr[i] = instr;
}
static void ir_block_naive_phi(ir_block *self)
{
size_t i, p, w;
/* FIXME: optionally, create_phi can add the phis
* to a list so we don't need to loop through blocks
* - anyway: "don't optimize YET"
*/
for (i = 0; i < self->instr_count; ++i)
{
ir_instr *instr = self->instr[i];
if (instr->opcode != VINSTR_PHI)
continue;
ir_block_instr_remove(self, i);
--i; /* NOTE: i+1 below */
for (p = 0; p < instr->phi_count; ++p)
{
ir_value *v = instr->phi[p].value;
for (w = 0; w < v->writes_count; ++w) {
ir_value *old;
if (!v->writes[w]->_ops[0])
continue;
/* When the write was to a global, we have to emit a mov */
old = v->writes[w]->_ops[0];
/* The original instruction now writes to the PHI target local */
if (v->writes[w]->_ops[0] == v)
v->writes[w]->_ops[0] = instr->_ops[0];
if (old->store != store_local)
{
/* If it originally wrote to a global we need to store the value
* there as welli
*/
ir_naive_phi_emit_store(self, i+1, old, v);
if (i+1 < self->instr_count)
instr = self->instr[i+1];
else
instr = NULL;
/* In case I forget and access instr later, it'll be NULL
* when it's a problem, to make sure we crash, rather than accessing
* invalid data.
*/
}
else
{
/* If it didn't, we can replace all reads by the phi target now. */
size_t r;
for (r = 0; r < old->reads_count; ++r)
{
size_t op;
ir_instr *ri = old->reads[r];
for (op = 0; op < ri->phi_count; ++op) {
if (ri->phi[op].value == old)
ri->phi[op].value = v;
}
for (op = 0; op < 3; ++op) {
if (ri->_ops[op] == old)
ri->_ops[op] = v;
}
}
}
}
}
ir_instr_delete(instr);
}
}
/***********************************************************************
*IR Temp allocation code
* Propagating value life ranges by walking through the function backwards
* until no more changes are made.
* In theory this should happen once more than once for every nested loop
* level.
* Though this implementation might run an additional time for if nests.
*/
typedef struct
{
ir_value* *v;
size_t v_count;
size_t v_alloc;
} new_reads_t;
MEM_VECTOR_FUNCTIONS_ALL(new_reads_t, ir_value*, v)
/* Enumerate instructions used by value's life-ranges
*/
static void ir_block_enumerate(ir_block *self, size_t *_eid)
{
size_t i;
size_t eid = *_eid;
for (i = 0; i < self->instr_count; ++i)
{
self->instr[i]->eid = eid++;
}
*_eid = eid;
}
/* Enumerate blocks and instructions.
* The block-enumeration is unordered!
* We do not really use the block enumreation, however
* the instruction enumeration is important for life-ranges.
*/
void ir_function_enumerate(ir_function *self)
{
size_t i;
size_t instruction_id = 0;
for (i = 0; i < self->blocks_count; ++i)
{
self->blocks[i]->eid = i;
self->blocks[i]->run_id = 0;
ir_block_enumerate(self->blocks[i], &instruction_id);
}
}
static void ir_block_life_propagate(ir_block *b, ir_block *prev, qbool *changed);
void ir_function_calculate_liferanges(ir_function *self)
{
size_t i;
qbool changed;
do {
self->run_id++;
changed = false;
for (i = 0; i != self->blocks_count; ++i)
{
if (self->blocks[i]->is_return)
ir_block_life_propagate(self->blocks[i], NULL, &changed);
}
} while (changed);
}
/* Get information about which operand
* is read from, or written to.
*/
static void ir_op_read_write(int op, size_t *read, size_t *write)
{
switch (op)
{
case VINSTR_JUMP:
case INSTR_GOTO:
*write = 0;
*read = 0;
break;
case INSTR_IF:
case INSTR_IFNOT:
case INSTR_IF_S:
case INSTR_IFNOT_S:
case INSTR_RETURN:
case VINSTR_COND:
*write = 0;
*read = 1;
break;
default:
*write = 1;
*read = 6;
break;
};
}
static qbool ir_block_living_add_instr(ir_block *self, size_t eid)
{
size_t i;
qbool changed = false;
qbool tempbool;
for (i = 0; i != self->living_count; ++i)
{
tempbool = ir_value_life_merge(self->living[i], eid);
/* debug
if (tempbool)
fprintf(stderr, "block_living_add_instr() value instruction added %s: %i\n", self->living[i]->_name, (int)eid);
*/
changed = changed || tempbool;
}
return changed;
}
static void ir_block_life_prop_previous(ir_block* self, ir_block *prev, qbool *changed)
{
size_t i;
/* values which have been read in a previous iteration are now
* in the "living" array even if the previous block doesn't use them.
* So we have to remove whatever does not exist in the previous block.
* They will be re-added on-read, but the liferange merge won't cause
* a change.
*/
for (i = 0; i < self->living_count; ++i)
{
if (!ir_block_living_find(prev, self->living[i], NULL)) {
ir_block_living_remove(self, i);
--i;
}
}
/* Whatever the previous block still has in its living set
* must now be added to ours as well.
*/
for (i = 0; i < prev->living_count; ++i)
{
if (ir_block_living_find(self, prev->living[i], NULL))
continue;
ir_block_living_add(self, prev->living[i]);
/*
printf("%s got from prev: %s\n", self->_label, prev->living[i]->_name);
*/
}
}
static void ir_block_life_propagate(ir_block *self, ir_block *prev, qbool *changed)
{
ir_instr *instr;
ir_value *value;
qbool tempbool;
size_t i, o, p, rd;
/* bitmasks which operands are read from or written to */
size_t read, write;
new_reads_t new_reads;
char dbg_ind[16] = { '#', '0' };
(void)dbg_ind;
VEC_INIT(&new_reads, v);
if (prev)
ir_block_life_prop_previous(self, prev, changed);
i = self->instr_count;
while (i)
{ --i;
instr = self->instr[i];
/* PHI operands are always read operands */
for (p = 0; p < instr->phi_count; ++p)
{
value = instr->phi[p].value;
/* used this before new_reads - puts the last read into the life range as well
if (!ir_block_living_find(self, value, NULL))
ir_block_living_add(self, value);
*/
/* fprintf(stderr, "read: %s\n", value->_name); */
if (!new_reads_t_v_find(&new_reads, value, NULL))
new_reads_t_v_add(&new_reads, value);
}
/* See which operands are read and write operands */
ir_op_read_write(instr->opcode, &read, &write);
/* Go through the 3 main operands */
for (o = 0; o < 3; ++o)
{
if (!instr->_ops[o]) /* no such operand */
continue;
value = instr->_ops[o];
/* We only care about locals */
if (value->store != store_value &&
value->store != store_local)
continue;
/* read operands */
if (read & (1<<o))
{
/* used this before new_reads - puts the last read into the life range as well
if (!ir_block_living_find(self, value, NULL))
ir_block_living_add(self, value);
*/
/* fprintf(stderr, "read: %s\n", value->_name); */
if (!new_reads_t_v_find(&new_reads, value, NULL))
new_reads_t_v_add(&new_reads, value);
}
/* write operands */
/* When we write to a local, we consider it "dead" for the
* remaining upper part of the function, since in SSA a value
* can only be written once (== created)
*/
if (write & (1<<o))
{
size_t idx, readidx;
qbool in_living = ir_block_living_find(self, value, &idx);
qbool in_reads = new_reads_t_v_find(&new_reads, value, &readidx);
if (!in_living && !in_reads)
{
/* If the value isn't alive it hasn't been read before... */
/* TODO: See if the warning can be emitted during parsing or AST processing
* otherwise have warning printed here.
* IF printing a warning here: include filecontext_t,
* and make sure it's only printed once
* since this function is run multiple times.
*/
/* For now: debug info: */
fprintf(stderr, "Value only written %s\n", value->_name);
tempbool = ir_value_life_merge(value, instr->eid);
*changed = *changed || tempbool;
/*
ir_instr_dump(instr, dbg_ind, printf);
abort();
*/
} else {
/* since 'living' won't contain it
* anymore, merge the value, since
* (A) doesn't.
*/
tempbool = ir_value_life_merge(value, instr->eid);
/*
if (tempbool)
fprintf(stderr, "value added id %s %i\n", value->_name, (int)instr->eid);
*/
*changed = *changed || tempbool;
/* Then remove */
ir_block_living_remove(self, idx);
if (in_reads)
new_reads_t_v_remove(&new_reads, readidx);
}
}
}
/* (A) */
tempbool = ir_block_living_add_instr(self, instr->eid);
//fprintf(stderr, "living added values\n");
*changed = *changed || tempbool;
/* new reads: */
for (rd = 0; rd < new_reads.v_count; ++rd)
{
if (!ir_block_living_find(self, new_reads.v[rd], NULL)) {
ir_block_living_add(self, new_reads.v[rd]);
}
if (!i && !self->entries_count) {
/* fix the top */
*changed = *changed || ir_value_life_merge(new_reads.v[rd], instr->eid);
}
}
new_reads_t_v_clear(&new_reads);
}
if (self->run_id == self->owner->run_id)
return;
self->run_id = self->owner->run_id;
for (i = 0; i < self->entries_count; ++i)
{
ir_block *entry = self->entries[i];
ir_block_life_propagate(entry, self, changed);
}
}
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